• Clinical and Experimental Reproductive Medicine
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• v.21 no.2
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• pp.165-176
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• 1994

This study was carried out to investigate the effect of the timing and dose of human chorionic gonadotropin(hCG) on oocyte recovery, in vitro fertilization, and preimplantation development in superovulation of mouse. F1 hybrid($C57BL{\times}CBA$) mice were obtained and superovulation was induced in female mice by sequential intraperitoneal injection of PMSG and hCG. In the first series of experiments, mice received 5 IU of PMSG given intraperitoneally, and 48 hours later were injected 1 IU, 5 IU, or 10 IU of hCG respectively. In the second series of experiments, mice received 5 IU of PMSG given intraperitoneally and were injected 5IU of hCG 36, 48, or 60 hours later respectively. 1. When the mice received 5 IU of PMSG given intraperitoneally and 48 hours later were injected 1 ItT, 5 IU, or 10 IU of hCG respectively, there were no differences in the total number of the oocytes obtained from the three experimental groups. When the cultures were examined 48 hrs after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observer to be lowest in 10 IU hCG group. When the cultrues were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was observed to be significantly higher in 10IU hCG group than 5IU hCG group(p<0.05), but there was no difference between 10 IU hCG group and 1IU hCG group. 2. When the mice received 5 IU of PMSG and were injected 5 IU of hCG 36, 48, or 60 hours later respectively, there were no differences in the total number of oocytes obtained from the three experimental groups. When cultures were examined 48 hour after the termination of insemination the proportion of unfragmented oocytes which had developed over two-cell stage was observed to be significantly lower in 36 hour interval group than 48 hour interval and 60 hour interval group(p<0.05). When the cultures were examined 120 hour after termination of insemination the proportion of embryos which had developed to the blastocyst stage was found to be higher in 60 hour interval group than 36 interval or 48 hour interval group (P<0.05), and the proportion of hatching blastocyst was found to be higher in 60 hour interval group as well. In this study, it was concluded that the administration of adequate dose of hCG, and long (60 hour) PMSG-hCG interval were necessary in superovulation of mice($C57BL{\times}CBA$) in order to get a large number of oocytes which had an early oocytes which had an early embryonic developmental capability when fertilized in vitro, and especially it had better have been avoided to administer a large dose of hCG.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.1-26
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• 1996

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.871-881
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• 1996

Objective: In the early short-term therapy of pulmonary tuberculosis, PZA is used for the first two months on 6EHRZ therapy but PZA is not effective in the case of long-tenn use PZA for retreatment in the sensitive relapse or acquired drug resistance for PZA. But in the endemic area as Korea, if we can't use PZA in the retreatment of pulmonary tuberculosis, we can't expect the success for retreatment of pulmonary tuberculosis, therefore we need new drugs substituting for PZA. In these days, 4 - fluoroquinolone derivatives were investigated and only ofloxacin and ciprofloxacin of derivatives were known to be effective but the effectiveness was also not certain because the result was experimental or combined with other bacteriocidal drugs and datas on effectiveness of pulmonary tuberculosis were so little. Therefore these drugs should be use with other two or three strong-acting drugs in the last period of retreatment of pulmonary tuberculosis. The ofloxacin or ciprofloxacin is used in some area in Korea but randomly and needed more study. We did this study for proving the effectiveness of these drugs and establishment of retreatment regimen for pulmonary tuberculosis. Methods: Retrospective cohort study of 83 drug-resistant pulmonary tuberculosis patients at National Masan Tuberculosis Hospital from Jan. 1994 to dec. 1995 was made. All the patients taken medicine for 2nd ami-tuberculosis regimens for the first lime. We separated the patients by two groups.(Group I : OFX+ PTA + CS+PAS + Injection, Group II: PZA + PTA+ CS + PAS + Injection). We compared the difference between two groups and tested the confidence limit about results after treatment by $\chi$2-test and T-test. Results : 1. The age distribution was most frequent in fourth decade(29.2% in Group I, 37.1% in Group II) and the mean age was 43.9 year in Group I, and 39.0 year in Group II, but had no significant difference between two groups. The sex distribution was more frequent in the males(68.8% in Group I, 85.7% in Group II), but had no significant difference. 2. Family history was 29.2% in Group I, 28.6% in Group II, but had no significant difference. 3. In the respect of extent of disease, far-advanced stare was 60.4% in Group I, 74.3% in Group II, but had no significant difference. 4. The side effects for drugs showed in 58.3% in Group I and 65.7% in Group II, and the gastrointestinal trouble showed 25.0% in Group and arthralgia 34.3% in Group II predominantly respectively and had the significant difference(p<0.05). 5. The negative conversion rate on sputum AFB smear was 87.5% in Group I and 80.0% in Group II, but had no significant difference. But the negative conversion rate on sputum AFB culture was 83.3% in Group I and 57.1 % in Group II and had the significant difference(p<0.05). 6. The success rate of treatment was 87.5 % in Group I and 83.3 % in Group II but had no significant difference. Conclusion : In the retreatment of pulmonary tuberculosis, ofloxacin is useful drug for the patients who are not available to use PZA and can be use effectively substituting for PZA.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.697-708
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• 1999

Background : Leukotriene (LT) $C_4$, $D_4$, and $E_4$, the main components of slow-reacting substance of anaphylaxis (SRS-A), have been suggested to play an important role in bronchial asthma such as antigen-induced bronchoconstriction, airway hyperreactivity, and pulmonary eosinophil accumulation. The purpose of this study was to evaluate the effects of treatment with the cysteinyl-LTs (cys-LTs) antagonist, pranlukast on allergen-induced guinea pig asthma model. Methods : Guinea pigs of treatment and placebo groups were sensitized by subcutaneous injection of ovalbumin(OVA) and challenged by inhalation of aerosolized OVA (1% weight/volume OVA). Normal control group did not sensitize with OVA. Oral ingestion of pranlukast and normal saline to the treatment and placebo groups was performed. In the treatment and placebo groups, airway resistance was measured before and after oral ingestion. Serum $LTC_4$ and eosinophilic infiltration of the bronchiolar and peribronchiolar tissues were measured after ingestion in the treatment and placebo groups. Results : Allergen-induced airway constriction developed in 20 (8 in treatment group, 12 in placebo group) among 35 guinea pigs. Airway resistance was significantly decreased at 3 and 6 minutes after OVA challenge in the pranlukast treatment group. In the placebo group, there was no difference of airway resistance between before and after saline ingestion. Serum $LTC_4$ levels showed 348.4 pg/ml in the treatment group, 373.9 pg/ml in the placebo group, and 364.4 pg/ml in the control group. There were no statistically significant difference between treatment and placebo group (p=0.232), and treatment and control group (p=0.501). Eosinophilic infiltrations in the peribronchiolar region per one-microscopic field ($\times$400 high power fields) demonstrated 7.06 in the treatment group, 19.2 in the placebo group, and 4.50 in the control group. There was significant decrement of eosinophilic infiltration in the treatment group which was compared with placebo group (p=0.001). Conclusion : These results demonstrate that pranlukast, a cys-LTs receptor antagonist, can attenuate allergen induced early-phase bronchoconstriction and eosinophilic infiltration in the bronchiolar tissues.

• The Korean Nurse
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• v.29 no.2
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• pp.48-65
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• 1990

The government has adopted a policy to introduce Home Health Care Program, and has established a three stage plan to implement it. The three stage plan is : First, to amend Article 54 (Nurses for Different Types of Services) of the Regulations for Implementing the Law of Medical Services; Second, to tryout the new system through pilot projects established in public hospitals and clinics; and third, to implement at all hospitals and equivalent medical institutions. In accordance with the plan, the Regulation has been amend and it was promulgated on January 9,1990, thus establishing a legal ground for implementing the policy. Subsequently, however, the Medical Association raised its objection to the policy, causing a delay in moving into the second stage of the plan. Under these circumstances, a study was conducted by collecting and evaluating the opinions of physicians, nurses, non-medical personnel and patients on the need and expected result from the home health care for the purpose of help facilitating the implementation of the new system. As a result of this study, it was revealed that: 1. Except the physicians, absolute majority of all other three groups - nurses, non-medical personnel and patients -gave positive answers to all 11 items related to the need for establishing a program for Home Health Care. Among the physicians, the opinions on the need for the new services were different depending on their field of specialty, and those who have been treating long term patients were more positive in supporting the new system. 2. The respondents in all four groups held very positive view for the effectiveness and the expected result of the program. The composite total of scores for all of 17 items, however, re-veals that the physicians were least positive for the- effectiveness of the new system. The people in all four groups held high expectation on the system on the ground that: it will help continued medical care after the discharge from hospitals; that it will alleviate physical and economic burden of patient's family; that it will offer nursing services at home for the patients who are suffering from chronic disease, for those early discharge from hospital, or those who are without family members to look after the patients at home. 3. Opinions were different between patients( who will receive services) and nurses (who will provide services) on the types of services home visiting nurses should offer. The patients wanted "education on how to take care patients at home", "making arrangement to be admitted into hospital when need arises", "IV injection", "checking blood pressure", and "administering medications." On the other hand, nurses believed that they can offer all 16 types of services except "Controlling pain of patients", 4. For the question of "what types of patients are suitable for Home Health Care Program; " the physicians, the nurses and non-medical personnel all gave high score on the cases of "patients of chronic disease", "patients of old age", "terminal cases", and the "patients who require long-term stay in hospital". 5. On the question of who should control Home Health Care Program, only physicians proposed that it should be done through hospitals, while remaining three groups recommended that it should be done through public institutions such as public health center. 6. On the question of home health care fee, the respondents in all four groups believed that the most desireable way is to charge a fixed amount of visiting fee plus treatment service fee and cost of material. 7. In the case when the Home Health Care Program is to be operated through hospitals, it is recommended that a new section be created in the out-patient department for an exclusive handling of the services, instead of assigning it to an existing section. 8. For the qualification of the nurses for-home visiting, the majority of respondents recommended that they should be "registered nurses who have had clinical experiences and who have attended training courses for home health care". 9. On the question of if the program should be implemented; 74.0% of physicians, 87.5% of non-medical personnel, and 93.0% of nurses surveyed expressed positive support. 10. Among the respondents, 74.5% of -physicians, 81.3% of non-medical personnel and 90.9% of nurses said that they would refer patients' to home health care. 11. To the question addressed to patients if they would take advantage of home health care; 82.7% said they would if the fee is applicable to the Health Insurance, and 86.9% said they would follow advises of physicians in case they were decided for early discharge from hospitals. 12. While 93.5% of nurses surveyed had heard about the Home Health Care Program, only 38.6% of physicians surveyed, 50.9% of non-medical personnel, and 35.7% of patients surveyed had heard about the program. In view of above findings, the following measures are deemed prerequisite for an effective implementation of Home Health Care Program. 1. The fee for home health care to be included in the public health insurance. 2. Clearly define the types and scope of services to be offered in the Home Health Care Program. 3. Develop special programs for training nurses who will be assigned to the Home Health Care Program. 4. Train those nurses by consigning them at hospitals and educational institutions. 5. Government conducts publicity campaign toward the public and the hospitals so that the hospitals support the program and patients take advantage of them. 6. Systematic and effective publicity and educational programs for home heath care must be developed and exercises for the people of medical professions in hospitals as well as patients and their families. 7. Establish and operate pilot projects for home health care, to evaluate and refine their programs.

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.290-297
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• 1998

Purpose : The aim of this study was to evaluate the feasibility of 3-[$^{131}I$]iodo-O-methyl-L-${\alpha}$-methyltyrosine ([$^{131}I$]OMIMT) as an agent for tumor image. Materials and Methods : After synthesis of 4-O-methyl-L-${\alpha}$-methyltyrosine (OMAMT), OMAMT was labeled with [$^{131}I$] using Iodogen method. In vitro cellular uptake study was performed using 9 L gliosarcoma cells at various time points upto 4 hr. The biodistribution (five rats implanted with the 9 L gliosar-coma cells per group) was evaluated at 30 min, 2 hr, 24 hr after iv injection of 3.7 MBq [$^{131}I$]OMIMT or L-3-[$^{131}I$]iodo-${\alpha}$-methyltyrosine [$^{131}I$]IMT). Gamma camera images were obtained at 30 min, 2 hr and 24 hr. Results: [$^{131}I$]OMIMT uptake was 3.3 times and 2.5 times higher than [$^{131}I$]IMT uptake at 30 min and 60 min, respectively and same after 2 hr in in vitro study using 9L gliosarcoma cells. Maximum accumulation in tumor occurred at 30 min for both [$^{131}I$]OMIMT and [$^{131}I$]IMT in tumor bearing rats. The tumor uptake of [$^{131}I$]OMIMT was significantly higher than that of [$^{131}I$]IMT at early time point studied ($3.74{\pm}0.48$ vs $0.38{\pm}0.17%$ ID/g at 30 min and $2.40{\pm}0.17$ vs $0.24{\pm}0.03%$ ID/g at 2 hr, respectively, p<0.01). However, the tumor uptake of both radiolabels were not significantly different at 24 hr ($0.04{\pm}0.01$ vs $0.05{\pm}0.01%$ ID/g). Tumor was visualized as early as at 30 min in gamma camera images. Conclusion: These data suggested that [$^{131}I$]OMIMT might be a useful tumor imaging agent and has more advantage for the tumor imaging compared to [$^{131}I$]IMT

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.1-11
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• 2008

As conventional oil and gas reservoirs become depleted, interests for oil sands has rapidly increased in the last decade. Oil sands are mixture of bitumen, water, and host sediments of sand and clay. Most oil sand is unconsolidated sand that is held together by bitumen. Bitumen has hydrocarbon in situ viscosity of >10,000 centipoises (cP) at reservoir condition and has API gravity between $8-14^{\circ}$. The largest oil sand deposits are in Alberta and Saskatchewan, Canada. The reverves are approximated at 1.7 trillion barrels of initial oil-in-place and 173 billion barrels of remaining established reserves. Alberta has a number of oil sands deposits which are grouped into three oil sand development areas - the Athabasca, Cold Lake, and Peace River, with the largest current bitumen production from Athabasca. Principal oil sands deposits consist of the McMurray Fm and Wabiskaw Mbr in Athabasca area, the Gething and Bluesky formations in Peace River area, and relatively thin multi-reservoir deposits of McMurray, Clearwater, and Grand Rapid formations in Cold Lake area. The reservoir sediments were deposited in the foreland basin (Western Canada Sedimentary Basin) formed by collision between the Pacific and North America plates and the subsequent thrusting movements in the Mesozoic. The deposits are underlain by basement rocks of Paleozoic carbonates with highly variable topography. The oil sands deposits were formed during the Early Cretaceous transgression which occurred along the Cretaceous Interior Seaway in North America. The oil-sands-hosting McMurray and Wabiskaw deposits in the Athabasca area consist of the lower fluvial and the upper estuarine-offshore sediments, reflecting the broad and overall transgression. The deposits are characterized by facies heterogeneity of channelized reservoir sands and non-reservoir muds. Main reservoir bodies of the McMurray Formation are fluvial and estuarine channel-point bar complexes which are interbedded with fine-grained deposits formed in floodplain, tidal flat, and estuarine bay. The Wabiskaw deposits (basal member of the Clearwater Formation) commonly comprise sheet-shaped offshore muds and sands, but occasionally show deep-incision into the McMurray deposits, forming channelized reservoir sand bodies of oil sands. In Canada, bitumen of oil sands deposits is produced by surface mining or in-situ thermal recovery processes. Bitumen sands recovered by surface mining are changed into synthetic crude oil through extraction and upgrading processes. On the other hand, bitumen produced by in-situ thermal recovery is transported to refinery only through bitumen blending process. The in-situ thermal recovery technology is represented by Steam-Assisted Gravity Drainage and Cyclic Steam Stimulation. These technologies are based on steam injection into bitumen sand reservoirs for increase in reservoir in-situ temperature and in bitumen mobility. In oil sands reservoirs, efficiency for steam propagation is controlled mainly by reservoir geology. Accordingly, understanding of geological factors and characteristics of oil sands reservoir deposits is prerequisite for well-designed development planning and effective bitumen production. As significant geological factors and characteristics in oil sands reservoir deposits, this study suggests (1) pay of bitumen sands and connectivity, (2) bitumen content and saturation, (3) geologic structure, (4) distribution of mud baffles and plugs, (5) thickness and lateral continuity of mud interbeds, (6) distribution of water-saturated sands, (7) distribution of gas-saturated sands, (8) direction of lateral accretion of point bar, (9) distribution of diagenetic layers and nodules, and (10) texture and fabric change within reservoir sand body.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.1
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• pp.41-48
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• 2007

Objective: To determine whether the presence of Y-chromosome microdeletion affects the outcome of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) program. Methods: Fourteen couples with microdeletion in azoospermic factor (AZF)c region who attempted IVF/ICSI or cryopreserved and thawed embryo transfer cycles were enrolled. All of the men showed severe oligoasthenoteratoazoospermia (OATS) or azoospermia. As a control, 12 couples with OATS or azoospermia and having normal Y-chromosome were included. Both groups were divided into two subgroups by sperm source used in ICSI such as those who underwent testicular sperm extraction (TESE) and those used ejaculate sperm. We retrospectively analyzed our database in respect to the IVF outcomes. The outcome measures were mean number of good quality embryos, fertilization rates, implantation rates, $\beta$-hCG positive rates, early pregnancy loss and live birth rates. Results: Mean number of good quality embryos, implantation rates, $\beta$-hCG positive rates, early pregnancy loss rates and live birth rates were not significantly different between Y-chromosome microdeletion and control groups. But, fertilization rates in the Y-chromosome microdeletion group (61.1%) was significantly lower than that of control group (79.8%, p=0.003). Also, the subgroup underwent TESE and having AZFc microdeletion showed significantly lower fertilization rates (52.9%) than the subgroup underwent TESE and having normal Y-chromosome (79.5%, p=0.008). Otherwise, in the subgroups used ejaculate sperm, fertilization rates were showed tendency toward lower in couples having Y-chromosome microdeletion than couples with normal Y-chromosome. (65.5% versus 79.9%, p=0.082). But, there was no significance statistically. Conclusions: In IVF/ICSI cycles using TESE sperm, presence of V-chromosome microdeletion may adversely affect to fertilization ability of injected sperm. But, in cases of ejaculate sperm available for ICSI, IVF outcome was not affected by presence of Y-chromosome AZFc microdeletion. However, more larger scaled prospective study was needed to support our results.

• Tuberculosis and Respiratory Diseases
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• v.63 no.3
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• pp.251-260
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• 2007

Purpose: An imbalance of cell proliferation and cell apoptosis is an important mechanism in carcinogenesis. Capase 3, survivin and p53 have been identified as important members of the apoptotic related proteins. This study evaluated the proliferating cell nuclear antigen(PCNA), apoptosis, apoptotic related protein such as capase 3, survivin and p53 using urethane-induced mouse lung carcinogenesis, which provides reproducible steps from hyperplasia to adenocarcinoma. Methods: Urethane was administered to the ICR mice through an intra-peritoneal injection, The mice were sacrificed at 5, 15, and 25 weeks after urethane intervention. The sequential morphological changes and immunohistochemical expression of PCNA, apoptosis, capase 3, survivin, and p53 were examined during mouse lung carcinogenesis. Results: During carcinogenesis, the sequential histological changes were observed from hyperplasia of type II pneumocytes, to anadenoma, and ultimately to an overt adenocarcinoma. The PCNA Labeling index (LI) was 9.6% in hyperplasia, 23.2% in adenoma, and 55.7% in adenocarcinoma, respectively. The apoptotic LI was 0.24% in hyperplasia, 1.25% in adenoma, and 5.27% in adenocarcinoma. A good correlation was observed between the PCNA LI and apoptotic LI. The expression of caspase 3 was remarkable- i.e., 46.7% in adenocarcinoma, in contrast to 15% in hyperplasia and 16% in adenoma. Survivin was detected weakly in the alveolar hyperplasia and showed an increasing expressional pattern in adenoma and adenocarcinoma. p53 expression was detected only in the adenocarcinoma lesions with an expression rate of 13.3%. The level of caspase 3 expression correlated with the increase in the apoptotic index. The positive expression of caspase 3 was associated with an increased apoptotic index. Conclusions: These results suggest that the PCNA LI and apoptotic LI might be useful markers for evaluating the risk of a malignant transformation. In addition, caspase, survivin and p53 might play a role in the early and late steges of urethane-induced mouse lung carcinogenesis.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.242-252
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• 1985

In order to get information on the ecology of rice false smut, germination ability and pathogenicity of sclerotia and chlamydospores of the pathogen, environmental conditions affecting the disease outbreak and varietal resistance have been investigated. 1. The degree of outbreak of rice false smut was higher in the upland rice in comparison with the paddy field rice in respect to the number of affected grains per ear, the size and weight of smut balls formed on affected grains as well as the ratio of sclerotial formation produced on smut balls. 2. Germination percentage and days required for germination of overwintered sclerotia placed on the soil surface in July were 81% and 19 days, respectively, while those of overwintered sclerotia treated in May were 60-70% and 41 days. Sclerotia placed on the soil surface or under 1 cm depth of the soil surface and incubated at $25-30^{\circ}C$ were germinated well, whereas those placed under 3 cm or 5 cm depth of the soil surface were not germinated at all. Germinability and stroma productivity of sclerotia were reduced when the sclerotia were cutted into small pieces. 3. The average number of stroma formed on a sclerotium was six and that of perithecia formed in a stroma was about 50 to 140. 4. Percentage of germination of chlamydospores on the yellow balls was very high and was decreased as the color of the balls being darken with maturation. 5. Panicle of rice plants were successfully infected by injection inoculation with suspention of ascospores and chlamydospores of the pathogen to the sheaths at the booting stages, while seeding infection by spraying with suspensions of chlamydospores was unsuccessful. 6. More number of infected grains was distributed on basal parts of an affected ear than that of infected ones distributed upper parts of the ear, when the affected ear was divided into five parts from its basal portion to the apical of the ear. 7. The occurrence of the disease was more severe in the late maturing varieties of rice in comparison with the early maturing varieties. 8. When the level of nitrogen applied was increased, the incidence of disease increased, and the infection percentage of the disease was increased as the transplanting date was delayed. 9. The weight of panicles and 1000 kernels and the ratio of ripenness were reduced, and the contamination degree of grains with chlamydospores were increased as the number of smut balls per panicle were increased.