• 한국유가공학회:학술대회논문집
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• 2007.09a
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• pp.49-58
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• 2007

Inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting abnormal intestinal wall function, even further accelerating the inflammatory process[1]. Despite of the records, etiology and pathogenesis of IBD remain rather unclear. There are many studies over the past couple of years have led to great advanced in understanding the inflammatory bowel disease(IBD) and their underlying pathophysiologic mechanisms. From the current understanding, it is likely that chronic inflammation in IBD is due to aggressive cellular immune responses including increased serum concentrations of different cytokines. Therefore, targeted molecules can be specifically eliminated in their expression directly on the transcriptional level. Interesting therapeutic trials are expected against adhesion molecules and pro-inflammatory cytokines such as TNF-${\alpha}$. The future development of immune therapies in IBD therefore holds great promises for better treatment modalities of IBD but will also open important new insights into a further understanding of inflammation pathophysiology. Treatment of cytokine inhibitors such as Immunex(Enbrel) and J&J/Centocor(Remicade) which are mouse-derived monoclonal antibodies have been shown in several studies to modulate the symptoms of patients, however, theses TNF inhibitors also have an adverse effect immune-related problems and also are costly and must be administered by injection. Because of the eventual development of unwanted side effects, these two products are used in only a select patient population. The present study was performed to elucidate the ability of TNF-${\alpha}$ antibodies produced in sheep colostrums to neutralize TNF-${\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. In vitro study, inhibitory effect of anti-TNF-${\alpha}$ antibody from the sheep was determined by cell bioassay. The antibody from the sheep at 1 in 10,000 dilution was able to completely inhibit TNF-${\alpha}$ activity in the cell bioassay. The antibodies from the same sheep, but different milkings, exhibited some variability in inhibition of TNF-${\alpha}$ activity, but were all greater than the control sample. In vivo study, the degree of inflammation was severe to experiment, despite of the initial pilot trial, main trial 1 was unable to figure out of any effect of antibody to reduce the impact of PAF and LPS. Main rat trial 2 resulted no significant symptoms like characteristic acute diarrhea and weight loss of colitis. This study suggested that colostrums from sheep immunized against TNF-${\alpha}$ significantly inhibited TNF-${\alpha}$ bioactivity in the cell based assay. And the higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent TNF-${\alpha}$ induced intestinal damage in the intact animal. Further study will require to find out an alternative animal model, which is more acceptable to test anti-TNF-${\alpha}$ IgA therapy for reducing the impact of inflammation on gut dysfunction. And subsequent pre-clinical and clinical testing also need generation of more antibody as current supplies are low.

• Journal of Intelligence and Information Systems
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• v.25 no.1
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• pp.163-177
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• 2019

As smartphones are getting widely used, human activity recognition (HAR) tasks for recognizing personal activities of smartphone users with multimodal data have been actively studied recently. The research area is expanding from the recognition of the simple body movement of an individual user to the recognition of low-level behavior and high-level behavior. However, HAR tasks for recognizing interaction behavior with other people, such as whether the user is accompanying or communicating with someone else, have gotten less attention so far. And previous research for recognizing interaction behavior has usually depended on audio, Bluetooth, and Wi-Fi sensors, which are vulnerable to privacy issues and require much time to collect enough data. Whereas physical sensors including accelerometer, magnetic field and gyroscope sensors are less vulnerable to privacy issues and can collect a large amount of data within a short time. In this paper, a method for detecting accompanying status based on deep learning model by only using multimodal physical sensor data, such as an accelerometer, magnetic field and gyroscope, was proposed. The accompanying status was defined as a redefinition of a part of the user interaction behavior, including whether the user is accompanying with an acquaintance at a close distance and the user is actively communicating with the acquaintance. A framework based on convolutional neural networks (CNN) and long short-term memory (LSTM) recurrent networks for classifying accompanying and conversation was proposed. First, a data preprocessing method which consists of time synchronization of multimodal data from different physical sensors, data normalization and sequence data generation was introduced. We applied the nearest interpolation to synchronize the time of collected data from different sensors. Normalization was performed for each x, y, z axis value of the sensor data, and the sequence data was generated according to the sliding window method. Then, the sequence data became the input for CNN, where feature maps representing local dependencies of the original sequence are extracted. The CNN consisted of 3 convolutional layers and did not have a pooling layer to maintain the temporal information of the sequence data. Next, LSTM recurrent networks received the feature maps, learned long-term dependencies from them and extracted features. The LSTM recurrent networks consisted of two layers, each with 128 cells. Finally, the extracted features were used for classification by softmax classifier. The loss function of the model was cross entropy function and the weights of the model were randomly initialized on a normal distribution with an average of 0 and a standard deviation of 0.1. The model was trained using adaptive moment estimation (ADAM) optimization algorithm and the mini batch size was set to 128. We applied dropout to input values of the LSTM recurrent networks to prevent overfitting. The initial learning rate was set to 0.001, and it decreased exponentially by 0.99 at the end of each epoch training. An Android smartphone application was developed and released to collect data. We collected smartphone data for a total of 18 subjects. Using the data, the model classified accompanying and conversation by 98.74% and 98.83% accuracy each. Both the F1 score and accuracy of the model were higher than the F1 score and accuracy of the majority vote classifier, support vector machine, and deep recurrent neural network. In the future research, we will focus on more rigorous multimodal sensor data synchronization methods that minimize the time stamp differences. In addition, we will further study transfer learning method that enables transfer of trained models tailored to the training data to the evaluation data that follows a different distribution. It is expected that a model capable of exhibiting robust recognition performance against changes in data that is not considered in the model learning stage will be obtained.

• Journal of Korean Academy of Nursing
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• v.25 no.2
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• pp.372-389
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• 1995

The frequency with which administration of chemotherapy for gynecological cancer treatment is used has increased along with the use of surgery and radiotherapy Among the various side effects of chemotherapy, stomatitis causes a problem of function and sensation in the oral cavity. This oral discomfort can be categorized into two components ; perceived oral symptoms and observed oral symptoms. If the oral problem continues, it may cause infection, bleeding and nutritional deficiencies. As a result of this condition, compliance with the treatment process can be affected as well as the prognosis for the cancer patients. But as the oral discorrfort usually appears after chemotherapy, it is often not reported to the health care personnel as a patient problem. Without problem identification of the oral discomfort and ability to assess the problem, effective intervention cannot be planned. Therefore, this study was conducted to identify the pattern and the degree of oral discomfort due to cancer chemotherapy and thus to provide data for identification of the patient problem and for nursing assessment. The design of this study was a longitudinal de-scriptive study The subjects were in - patients who received chemotherapy under the diagnosis of gynecological cancer between Mar. 15, 1994 and May 15, 1994 at a general hospital in Seoul, Korea. The number of subjects was 64 and they were divided into two groups, one of 41 (A : 5FU & Neoplatin), the other of 23(B : Neoplatin, Cytoxan, Adriamycin), according to the treatment regimen. The data were collected for 24 days using self-re-port instruments. The instruments were the 「Perceived Oral Symptom Assessment Tool」 and 「Observed Oral Symptom Assessment Tool」 developed by this researcher. Data were analyzed using the SPSS-PC program, ANOVA, t-test, paired t-test and the Pearson Correlation Coefficient were applied. The results of this study are as follows : 1. In A regimen the peak time for perceived oral symptom scores was the fifth day after chemotherapy, and the tenth day for observed oral symptom scores. Both of the problems started on first day of chemotherapy and were not resolved completely until the 24th day after treatment. 2. In B regimen, the peak time for perceived oral symptom scores was on the seventh day after chemotherapy, and the eighth day for observed oral symptom scores. It was noted that perceived oral symptom scores were higher than observed oral symptom scores consistently for 24 days. Both also started on first day of chemotherapy, and were not resolved completely until the 24th day after chemotherapy. 3. There were no differences statistically in perceived oral symptom scores between A and B regimen. The loss of appetite and xerostomia caused the most severe discomfort in both of these two groups. 4. The were no differences statistically in observed oral symptom scores between the A and B regi moil. In the A regimen, the highest observed symptom scores were the lips, gingiva, tongue and buccal membrane in that order. But in the B regimen, the highest observed symptom scores were tongue, lips, buccal membrane and gingiva in that order. 5. In A regimen, the patients who had gingival edema and dentures had significantly higher perceived oral symptom scores. And those who had gingival edema and bleeding, foul odor and aphthous stomatitis had significantly higher observed oral symptom scores. 6. In B regimen, the patients who had the experience of stomatitis in the last course of chemotherapy had significantly higher perceived oral symptom scores. Those who had gingival edema had significantly higher observed oral symptom scores. 7. In the A regimen there was no correlation between lab values for lymphocytes and albumin with perceived oral symptom scores and observed oral symptom scores. In the B regimen, there was a significant negative correlation between lymphocytes and albumin with the observed oral symptom scores, but not between perceived oral symptom scores and lymphocytes and albumin values. In conclusion, the nurse should expect that the patient undergoing chemotherapy will complain severely about subjective discomfort and before objective physical change is observed. Also the patients who have chronic oral problems such as dentures, gingival edema and bleeding, foul odor, aphthous stomatitis will complain of severe oral discomfort due to chemotherapy.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.117-128
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• 2002

Objectives：For the purpose of obtaining the more vivid present status and prevention program of teenage pregnancy, this survey was done by Obstetricians, as study subject, who manage the pregnant teenager in real clinical situation. Methods：Structured survey form about teenage pregnancy was sent to 2,800 obstetricians. That form contained frequency, characteristics, decision making processes, and psychiatric aspects of the teenage pregnancy. 349 obstetricians replied that survey form and we analysed these datas. Results：(1) The trend of teenage pregnancy was mildly increased. (2) The most common cases were unwanted pregnancy by continuing sexual relationship with boyfriends rather than by forced, accidental sexual relationship with multiple partners. (3) The most common reason of labor was loss the time of artificial abotion. (4) Problems of pregnant girls' were conduct behaviors and poor informations about contraception rather than sexual abuse or mental retardation. (5) Most obstetricians percepted the necessity of psychiatric consultation, however psychiatric consultation was rare due to parents refusal and abscense of available psychiatric facility. (6) For the prevention of teenage pregnancy, the most important thing was practical education about contraception. Conclusions：Based on the result of this study, further study using structured interview schedule with pregnant girl is needed for the detecting risk factor of teenage pregnancy and effective systematic approach to pregnant girl.

• Journal of muscle and joint health
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• v.5 no.2
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• pp.238-252
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• 1998

Reumatic arthritis is a disease with joint pain being one of the key symptoms. The patient suffers from the pain, stiff sensation and edema due to the inflammation taking Place In one or more joints. Accompanying these problems are fatigue, unusual exhaustion, fever, tachycardia and weakness. Inaddition, joints are often deformed and muscles shrink along with the progress of edema, coupled with depression and psychological instability resulting from the loss of the mobile function and limitations on the daily life. Some patients become fed up with the long and hard flight with the disease and just give up, which aggravates the symptoms. Others come to the hospital only when the conditions have become serious. We need to prevent these and guide the patients in the right direction. Against this backdrop, this study aims to look into the relations between the knowledge on the part of the patients together with their feeling of self-efficacy and the compliance. The results are expected to help the patients improve their life, In addition to providing useful materials for setting up appropriate plan for nursing intervention. The study was conducted by distributing questionnaire to 88 patients selected from the out-patient department of a university hospital in Inchon, from April 6 to 27, 1998. The following tools were used the yardstick of self-efficacy, developed in 1997 by the Society for the Health of Rheumatism Patients, was used for measuring the levels of knowledge and the feeling of self-efficacy. The degree of compliance was measured by the data collected from documents in addition to the results of the analysis of the interviews with the patients. The reliability of the tools was confirmed. In the analysis, the general characteristics were expressed in figures and percentages. The levels of knowledge, feeling of self-efficacy, and compliance were expressed in the average values and standard deviations. The relations among the variables following the general characteristics were analysed by the t-test and one-way ANOVA. The Pearson correction coefficient was used for the analysis of factors. Multiple-loop analysis was used to identify the variables affecting the compliance. The following are the results of this study. 1. Among the 88 patients, 18 were men and the remaining 70 were women, with a ratio 1 : 3.87. Regarding the age groups, 23 were between 50 and 59 years old, with those between 50 and 69 accounting for 51.1% of the total. High school graduates or higher amounted to 58%. Religious patients was 67% or 59 persons. Fifty nine percent were unemployed, and 58.3% (49 persons) had two children or fewer. The period of suffering from rheumatism varied between 2 months and IS years, with 70% less than years. 2. The average figure In relation to the of knowledge was 17.63 points over 30 or 58. 76%, which means a medium level. 3. The average figure of the feeling of self-efficacy was 60.06 points. 4. The level of compliance was 3.26, which was above average. 5. The relation between the feeling of self-efficacy and compliance showed an "r" value of 0.37, which was significant. It means that the higher the feeling, the greater the compliance points. 6. The analysis of the knowledge level revealed that the difference is found only between the college graduates and junior-high graduates or lower. 7. The feeling of self-efficacy varied along with the age and education level. 8. The general characteristics of patients as discussed above did not show significant difference with the compliance. 9. Regarding the elements influencing the compliance, the number of children, period of suffering, income, age, feering of self-efficacy, knowledge, and compliance had 54% of significance. In conclusion, rheumatism victims can lead a better life if they are appropriately educated, based on efficient training program from the early days of the disease ; if they become able to manage themselves thanks to the training ; and if they are helped by a program focusing on the increase of the feeling of self-efficacy aimed at changing patient's behavior.

• Childhood Kidney Diseases
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• v.5 no.2
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• pp.164-175
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• 2001

Purpose : Alport syndrome is a hereditary nephrotic disease characterized by progressive nephrotic symptom, sensorineural hearing loss, ophthalmic abnormality, typical microscopic findings, and familial occurrence. In this study, we tried to find the risk factors related with its prognosis by taking a close observation on clinical symptoms of children with Alport syndrome reviewing retrospectively. Materials & methods : We chose children diagnosed as Alport syndrome in renal biopsy during 20 years(from 1980, Jan. until 1999, Dec.) who could receive follow up studies in tile department of pediatrics. They were divided into two groups by comparing renal function at the time of diagnosis and at current status. We compared several clinical aspects in them, and applied nonparametric test for statistical analysis. Results : The sex ratio(male:female) of 24 children was 3:1. The most common clinical symptom presented at their first visit was gross hematuria. Among those 24 children, 11 cases($46\%$) of progressing into chronic renal failure(Group II) were observed. Hypertension, proteinuria and edema were seen much frequently in group II. The level of serum protein, albumin, and creatinine clearance were decreased while BUN, creatinine were relatively increased. All the results were statistically significant. Conclusion Clinically significant risk factors related to prognosis in Alport syndrome were the presence of hypertension, edema, and proteinuria at the time of diagnosis. Also, the level of serum protein, albumin, BUN, creatinine, and glomerular filtration rate were proved to be important factors in predicting prognosis. We believe that studies on these possible risk factors would be of great help in treating and predicting prognosis of children suffering with Alport syndrome. (J Korean Soc Pediatr Nephrol 2001;5 : 164-75)

• Journal of Chest Surgery
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• v.30 no.10
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• pp.991-1000
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• 1997

Closed thoracostomy with UWSD* which is the most utilized procedure in chest surgery applies general thoracic disorders, trauma and after-thoracic surgery. The University hospital was involved on operating 2341 cases of closed thoracostomy with UWSD except chest tubing after-thoracic surgery for a full six years from January, 1991 to December, 1996. The rate of men and women out of the total 2341 cases was 3.5 : 1, the distribution by age showed that men were 36.6 $\pm21.0$ years old, women were $47.0\pm20.2$ years old and so that the total were 40.0 $\pm$ 20.5 years old. As for indication, spontaneous, secondary and traumatic pneumothorax were the most common, in addition to hemothorax hemopneumothorax, hydrothorax, hydropneumothorax, empyema, chylothorax. The most indwelling period of chest tubing is between eight and fourteen days for 974 cases and the average is 13.7 $\pm$ 6.3 days, The average drainage amount immediately after thoracostomy was 537 $\pm$ 88m1, and in 694 cases(46.0%), the drain amount was 201 ~ 500 ml. The rate of right and left tubing was 52.4 47.6, in 2071 cases(88.5%), the thoracostomy was the first chance and 2210 cases(94.4%) were treated with a single tube drainage. Almost all the patients complained of tube site pain, besides tube site infection, intercostal neuralgia, loss of tube function by the pleural adhesion, intrathoracic infection, incomplete reexpansion of defective lung, hemorrhage caused by the rupture of a blood vessel, subcutaneous emphysema, lung parenchymal rupture, diaphragmatic and intraabdominal trauma, reexpansionary pulmonary edema of one side lung and cellulitis were relapsed. 84.6% of all patients recovered with only clo ed thoracostomy and the rest of patient needed additional some necessary managements and so on to have successful results. There were two deaths(0.1%), caused by reexpansionary pulmonary edema, the cellulitis were complicated by thoracostomy with UWSD on an empyema patients to come to death(due to sepsis). t UWSD = under water seal drainage

• Journal of Chest Surgery
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• v.42 no.1
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• pp.9-13
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• 2009

Background: Hypoplastic left heart syndrome is uniformly fatal if this condition is not properly treated. We reviewed the surgical results of treating hypoplastic left heart syndrome, and we evaluated the hemodynamics and functional status of these patients after they underwent a Fontan operation. Material and Method: To assess the surgical results, we retrospectively reviewed the medical records of 6 (M/F=4/2) patients who underwent a staged operation, including a Norwood procedure, a bidirectional Glenn procedure and a Fontan procedure between October 1997 to May 2005. The mean age of the patients was $17.3{\pm}10.8$ days (range: 9~36 days) at the $1^{st}$ staged operation, $8.9{\pm}7.1$ months (4.6~23.3 months) at the $2^{nd}$ staged operation (the Bidirectional Glenn procedure) and $32.4{\pm}9.8$ months at the final staged operation (the Fontan procedure). During the $2^{nd}$ staged operation, one of the patients received tricuspid valve repair due to regurgitation. All the patients underwent an extracardiac Fontan procedure using Gore-Tex conduit (20 mm: 2 patients, 18 mm: 4 patients) and one of them required fenestration. Result: 21 patients underwented a Norwood procedure. There were 7 early deaths and 4 interstage deaths. Bidirectional cavopulmonary shunt was performed in 10 patients and the Fontan procedure was done in 6 (mortality: 1 patient, Flow up loss: 1 patient, Awaiting a Fontan procedure: 2 patients). After the Fontan procedure, there was no complication except for one case of post operative bleedings. All the patients had good ventricular function and 2 had grade I tricuspid regurgitation, as noted on their echocardiography. The average follow up period after the Fontan procedure was $19.6{\pm}14.9$ months (range: 1.5~39.1 month). All the patients had normal sinus rhythm and they were put on aspirin and cardiac medication. During follow up period, all the patients had a good functional status (NYHA functional class I). Conclusion: All the patients who suffered with hypoplastic left heart syndrome and who underwent a Fontan procedure achieved a good hemodynamic and functional status, even though there was a relatively high operative mortality rate after stage I Norwood palliation. Therefore, thise staged operation should be strongly recommended as an important surgical strategy for treating hypoplastic left heart syndrome.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.27-47
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• 1992

Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.261-270
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• 1992

Many herbicides that are applied at the soil before weed emergence inhibit plant growth soon after weed germination occurs. Plant growth has been known as an irreversible increase in size as a result of the processes of cell divison and cell enlargement. Herbicides can influence primary growth in which most new plant tissues emerges from meristmatic region by affecting either or both of these processes. Herbicides which have sites of action during interphase($G_1$, S, $G_2$) of cell cycle and cause a subsequent reduction in the observed frequency of mitotic figures can be classified as an inhibitor of mitotic entry. Those herbicides that affect the mitotic sequence(mitosis) by influencing the development of the spindle apparatus or by influencing new cell plate formation should be classified as causing disruption of the mitotic sequence. Sulfonylureas, imidazolinones, chloroacetamides and some others inhibit plant growth by inhibiting the entry of cell into mitosis. The carbamate herbicides asulam, carbetamide, chlorpropham and propham etc. reported to disrupt the mitotic sequence, especially affecting on spindle function, and the dinitroaniline herbicides trifluralin, nitralin, pendimethalin, dinitramine and oryzalin etc. reported to disrupt the mitotic sequence, particularly causing disappearence of microtubles from treated cells due to inhibition of polymerization process. An inhibition of cell enlargement can be made by membrane demage, metabolic changes within cells, or changes in processes necessary for cell yielding. Several herbicides such as diallate, triallate, alachlor, metolachlor and EPTC etc. reported to inhibit cell enlargement, while 2, 4-D has been known to disrupt cell enlargement. One potential danger inherent in the use of soil acting herbicides is that build-up of residues could occur from year to year. In practice, the sort of build-up that would be disastrous is unikely to occur for substances applied at the correct soil concentration. Crop injury caused by soil applied herbicides can be minimized by (1) following the guidance of safe use of herbicides, particularly correct dose at correct time in right crop, (2) by use of safeners which protect crops against injury without protecting any weed ; interactions between herbicides and safeners(antagonists) at target sites do occur probably from the following mechanisms (1) competition for binding site, (2) circumvention of the target site, and (3) compensation of target site, and another mechanism of safener action can be explained by enhancement of glutathione and glutathione related enzyme activity as shown in the protection of rice from pretilachlor injury by safener fenclorim, (3) development of herbicide resistant crops ; development of herbicide-resistant weed biotypes can be explained by either gene pool theory or selection theory which are two most accepted explanations, and on this basis it is likely to develop herbicide-resistant crops of commercial use. Carry-over problems do occur following repeated use of the same herbicide in an extended period of monocropping, and by errors in initial application which lead to accidental and irregular overdosing, and by climatic influence on rates of loss. These problems are usually related to the marked sensitivity of the particular crops to the specific herbicide residues, e.g. wheat/pronamide, barley/napropamid, sugarbeet/ chlorsulfuron, quinclorac/tomato. Relatively-short-residual product, succeeding culture of insensitive crop to specific herbicide, and greater reliance on postemergence herbicide treatments should be alternatives for farmer practices to prevent these problems.