• Journal of Korean Neurosurgical Society
• /
• v.50 no.3
• /
• pp.166-172
• /
• 2011

Objective : The intralaminar screw (ILS) fixation technique offers an alternative to pedicle screw (PS) and lateral mass screw (LMS) fixation in the C7 spine. Although cadaveric studies have described the anatomy of the pedicles, laminae, and lateral masses at C7, 3-dimensional computed tomography (CT) imaging is the modality of choice for pre-surgical planning. In this study, the goal was to determine the anatomical parameter and optimal screw trajectory for ILS placement at C7, and to compare this information to PS and LMS placement in the C7 spine as determined by CT evaluation. Methods : A total of 120 patients (60 men and 60 women) with an average age of $51.7{\pm}13.6$ years were selected by retrospective review of a trauma registry database over a 2-year period. Patients were included in the study if they were older than 15 years of age, had standardized axial bone-window CT imaging at C7, and had no evidence of spinal trauma. For each lamina and pedicle, width (outer cortical and inner cancellous), maximal screw length, and optimal screw trajectory were measured, and the maximal screw length of the lateral mass were measured using m-view 5.4 software. Statistical analysis was performed using Student's t-test. Results : At C7, the maximal PS length was significantly greater than the ILS and LMS length (PS, $33.9{\pm}3.1$ mm; ILS, $30.8{\pm}3.1$ mm; LMS, $10.6{\pm}1.3$; p<0.01). When the outer cortical and inner cancellous width was compared between the pedicle and lamina, the mean pedicle outer cortical width at C7 was wider than the lamina by an average of 0.6 mm (pedicle, $6.8{\pm}1.2$ mm; lamina, $6.2{\pm}1.2$ mm; p<0.01). At C7, 95.8% of the laminae measured accepted a 4.0-mm screw with a 1.0 mm of clearance, compared with 99.2% of pedicle. Of the laminae measured, 99.2% accepted a 3.5-mm screw with a 1.0 mm clearance, compared with 100% of the pedicle. When the outer cortical and inner cancellous height was compared between pedicle and lamina, the mean lamina outer cortical height at C7 was wider than the pedicle by an average of 9.9 mm (lamina, $18.6{\pm}2.0$ mm; pedicle, $8.7{\pm}1.3$ mm; p<0.01). The ideal screw trajectory at C7 was also measured ($47.8{\pm}4.8^{\circ}$ for ILS and $35.1{\pm}8.1^{\circ}$ for PS). Conclusion : Although pedicle screw fixation is the most ideal instrumentation method for C7 fixation with respect to length and cortical diameter, anatomical aspect of C7 lamina is affordable to place screw. Therefore, the C7 intralaminar screw could be an alternative fixation technique with few anatomic limitations in the cases when C7 pedicle screw fixation is not favorable. However, anatomical variations in the length and width must be considered when placing an intralaminar or pedicle screw at C7.

• Bulletin of the Korean Mathematical Society
• /
• v.57 no.6
• /
• pp.1351-1365
• /
• 2020

Let S and T be w-linked extension domains of a domain R with S ⊆ T. In this paper, we define what satisfying the w_R-GD property for S ⊆ T means and what being w_R- or w-GD domains for T means. Then some sufficient conditions are given for the w_R-GD property and w_R-GD domains. For example, if T is w_R-integral over S and S is integrally closed, then the w_R-GD property holds. It is also given that S is a w_R-GD domain if and only if S ⊆ T satisfies the w_R-GD property for each w_R-linked valuation overring T of S, if and only if S ⊆ (S[u])_w satisfies the w_R-GD property for each element u in the quotient field of S, if and only if S_𝔪 is a GD domain for each maximal w_R-ideal 𝔪 of S. Then we focus on discussing the relationship among GD domains, w-GD domains, w_R-GD domains, Prüfer domains, PνMDs and Pw_RMDs, and also provide some relevant counterexamples. As an application, we give a new characterization of Pw_RMDs. We show that S is a Pw_RMD if and only if S is a w_R-GD domain and every w_R-linked overring of S that satisfies the w_R-GD property is w_R-flat over S. Furthermore, examples are provided to show these two conditions are necessary for Pw_RMDs.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.8
• /
• pp.1172-1180
• /
• 2013

Two experiments were conducted to determine the standardized ileal digestible (SID) lysine (Lys) requirement and the ideal SID threonine (Thr) to Lys ratio for finishing barrows. In Exp. 1, 120 barrows with an average body weight of $72.8{\pm}3.6$ kg were allotted to one of six dietary treatments in a randomized complete block design conducted for 35 d. Each diet was fed to five pens of pigs containing four barrows. A normal crude protein (CP) diet providing 15.3% CP and 0.71% SID Lys and five low CP diets providing 12% CP with SID Lys concentrations of 0.51, 0.61, 0.71, 0.81 and 0.91% were formulated. Increasing the SID Lys content of the diet resulted in an increase in weight gain (linear effect p = 0.04 and quadratic effect p = 0.08) and an improvement in feed conversion ratio (FCR) (linear effect p = 0.02 and quadratic effect p = 0.02). For weight gain and FCR, the estimated SID Lys requirement of finishing barrows were 0.71 and 0.71% (linear broken-line analysis), 0.79 and 0.78% (quadratic analysis), respectively. Exp. 2 was a 26 d dose-response study using SID Thr to Lys ratios of 0.56, 0.61, 0.67, 0.72 and 0.77. A total of 138 barrows weighing $72.5{\pm}4.4$ kg were randomly allotted to receive one of the five diets. All diets were formulated to contain 0.61% SID Lys (10.5% CP), which is slightly lower than the pig's requirement. Weight gain was quadratically (p = 0.03) affected by SID Thr to Lys ratio while FCR was linearly improved (p = 0.02). The SID Thr to Lys ratios for maximal weight gain and minimal FCR and serum urea nitrogen (SUN) were 0.67, 0.71 and 0.64 using a linear broken-line model and 0.68, 0.78 and 0.70 using a quadratic model, respectively. Based on the estimates obtained from the broken-line and quadratic analysis, we concluded that the dietary SID Lys requirement for both maximum weight gain and minimum FCR was 0.75%, and an optimum SID Thr to Lys ratio was 0.68 to maximize weight gain, 0.75 to optimize FCR and 0.67 to minimize SUN for finishing barrows.

• Journal of Chest Surgery
• /
• v.29 no.1
• /
• pp.14-23
• /
• 1996

Circulatory arrest under deep hypothermia is an important auxiliary means for cardiac surgery, especially useful in pediatric patients. However, its clinical safety, particularly with regard to the neurologic outcome after long duration of circulatory arrest, is still not established. This study is a review of the eight years'clinical experience of hypothermic circulatory arrest at the Seoul national University Children's Hospital. During an eight-year period from January 1986 through December 1993, a total of 589 consecutive cardiac operations were done using circulatory arrest under deep hypothermia. Among them, 434 consecutive patients, in whom the duration of arrest was 20 minutes or more, are the subject of this study. The duration of arrest ranged from 20 minutes to 82 minutes (mean = 38.7 minutes) under rectal temperature in the range from 12.5$^{\circ}C$ to 25.8$^{\circ}C$. Early neurologic abnormalities occurred in 47 patients : seizure attacks in 28 patients, motor paralyses with or w thout seizure in 12, blindness in 2, and no recovery of consciousness in 5 patients. The rate of incidence of early neurologic abnormalities was calculated at 15.7%. 25 patients showed late neuropsychologic sequelae, such as motor paralysis (9 patients), recurrent seizures (6), developmental delay (8), and definitely low intelligence (2). The rate of incidence of late neurologic sequelae was 8.5%, By statistical analysis, the following factors were identified as the risk factors for post-arrest neurologic abnormalities ; 1) long duration of circulatory arrest, 2) lower-than-ideal body weight, 3) preexisting neurological abnormalities, 4) associated non-cardiovascular congenital anouialies, and 5) low blood pressure during the early post-arrest period. It is concluded that circulatory arrest under deep hypothermia is a relatively safe means for pediatric cardiac surgery with acceptable risk. However, to warrant maximal safety, it is desirable to limit the duration of arrest to less th n 40 minutes. In addition, it is our contention that the early post-arrest period is a very critical period during which maintenance of adequate perfusion pressure in important for the neurologic outcome.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.12
• /
• pp.1664-1672
• /
• 2014

In this study, a fibrous bed bioreactor (FBB) was used for $\small{D}$-lactic acid ($\small{D}$-LA) production by Sporolactobacillus inulinus Y2-8. Corn flour hydrolyzed with ${\alpha}$-amylase and saccharifying enzyme was used as a cost-efficient and nutrient-rich substrate for $\small{D}$-LA production. A maximal starch conversion rate of 93.78% was obtained. The optimum pH for $\small{D}$-LA production was determined to be 6.5. Ammonia water was determined to be an ideal neutralizing agent, which improved the $\small{D}$-LA production and purification processes. Batch fermentation and fed-batch fermentation, with both free cells and immobilized cells, were compared to highlight the advantages of FBB fermentation. In batch mode, the $\small{D}$-LA production rate of FBB fermentation was 1.62 g/l/h, which was 37.29% higher than that of free-cell fermentation, and the $\small{D}$-LA optical purities of the two fermentation methods were above 99.00%. In fe$\small{D}$-batch mode, the maximum $\small{D}$-LA concentration attained by FBB fermentation was 218.8 g/l, which was 37.67% higher than that of free-cell fermentation. Repeate$\small{D}$-batch fermentation was performed to determine the long-term performance of the FBB system, and the data indicated that the average $\small{D}$-LA production rate was 1.62 g/l/h and the average yield was 0.98 g/g. Thus, hydrolyzed corn flour fermented by S. inulinus Y2-8 in a FBB may be used for improving $\small{D}$-LA fermentation by using ammonia water as the neutralizing agent.

• Journal of the Korean Arthroscopy Society
• /
• v.12 no.1
• /
• pp.18-23
• /
• 2008

Purpose: The purpose of this study is to evaluate the clinical results of the function and stability of ACL reconstruction using the flexible reamer. Materials and Methods: We reviewed 98 patients who taken ACL reconstruction using the flexible reamer from March, 1999 to May, 2004. And the follow-up period was more than 12 months in all cases. We used the subjective tests including Lysholm knee score and 2000 International Knee Documentation Committee(IKDC) subjective knee score, and the objective tests such as anterior drawer test, Lachman test, pivot shift test, and KT-2000 arthrometer to evaluate the clinical results. Results: In the range of motion of the affected knee, the extension deficit more than 5 degree was 8 cases preoperatively and 1 case postoperatively. The flexion deficit more than 5 degree was 12 cases preoperatively and 2 cases postoperatively. The mean Lysholm knee score was 61.3 point(${\pm}3.5$ SD) preoperatively and 87.7 point(${\pm}2.0$ SD) postoperatively. The mean 2000 International Knee Documentation Committee(IKDC) subjective knee score was 49 point(${\pm}3.3$ SD) preoperatively and 84 point (${\pm}2.2$ SD) postoperatively. 93 cases were more than grade II in Lachman test preoperatively and 5 cases postoperatively. 71 cases were more than grade II in pivot shift test preoperatively but 89 cases were negative postoperatively. The mean maximal manual difference by KT-2000 arthrometer was 6.8 mm(${\pm}1.9$ SD) preoperatively and 1.8 mm(${\pm}0.8$ SD) postoperatively. Conclusion: ACL reconstruction using the flexible reamer achieved the ideal isometric point of femur and anatomic graft placement, so we could obtain good results, especially in rotational stability.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.4
• /
• pp.1909-1915
• /
• 2016

Background: The purpose of this study was to determine the benefit of tertiary cytoreductive surgery (TC) for secondary recurrent epithelial ovarian cancer (EOC), focusing on whether optimal cytoreduction has an impact on disease-free survival, and whether certain patient characteristics could identify ideal candidates for TC. Materials and Methods: Retrospective analysis of secondary recurrent EOC patients undergoing TC at three Turkish tertiary institutions from May 1997 to July 2014 was performed. All patients had previously received primary cytoreduction followed by intravenous platinum-based chemotherapy and secondary cytoreduction for first recurrence. Clinical and pathological data were obtained from the patients' medical records. Survival analysis was caried out using the Kaplan Meier method. Actuarial curves were compared by the two tailed Logrank test with a statistical significance level of 0.05. Results: Median age of the patients was 49.6 years (range, 30-67) and thirty-eight (72%) had stage III-IV disease at initial diagnosis. Twenty six (49%) had optimal and 27 (51%) suboptimal cytoreduction during tertiary debulking surgery. Optimal initial cytoreduction, time to first recurrence, optimal secondary cytoreduction, time interval between secondary cytoreduction and secondary recurrence, size of recurrence, disease status at last follow-up were found to be significant risk factors to predict optimal TC. Optimal cytoreduction in initial and tertiary surgery and serum CA-125 level prior to TC were independent prognostic factors on univariate analysis. Conclusions: Our results and a literature review clearly showed that maximal surgical effort should be made in TC, since patients undergoing optimal TC have a better survival. Thus, patients with secondary recurrent EOC in whom optimal cytoreduction can be achieved should be actively selected.

• Radiation Oncology Journal
• /
• v.23 no.4
• /
• pp.236-242
• /
• 2005

Purpose: To evaluate the role of surgical clips and scars in determining electron boost field for early stage breast cancer undergoing conserving surgery and postoperative radiotherapy and to provide an optimal method in drawing the boost field. Materials and Methods: Twenty patients who had $4{\sim}7$ surgical clips in the excision cavity were selected for this study. The depth informations were obtained to determine electron energy by measuring the distance from the skin to chest wall (SCD) and to the clip implanted in the most posterior area of tumor bed. Three different electron fields were outlined on a simulation film. The radiological tumor bed was determined by connecting all the clips implanted during surgery Clinical field (CF) was drawn by adding 3 cm margin around surgical scar. Surgical field (SF) was drawn by adding 2 cm margin around surgical clips and an Ideal field (IF) was outlined by adding 2 cm margin around both scar and clips. These fields were digitized into our planning system to measure the area of each separate field. The areas of the three different electron boost fields were compared. Finally, surgical clips were contoured on axial CT images and dose volume histogram was plotted to investigate 3-dimensional coverage of the clips. Results : The average depth difference between SCD and the maximal clip location was $0.7{\pm}0.55cm$. Greater difference of 5 mm or more was seen in 12 patients. The average shift between the borders of scar and clips were 1.7 1.2, 1.2, and 0.9 cm in superior, inferior, medial, and lateral directions, respectively. The area of the CF was larger than SF and IF in 6y20 patients. In 15/20 patients, the area difference between SF and if was less than 5%. One to three clips were seen outside the CF in 15/20 patients. In addition, dosimetrically inadequate coverage of clips (less than 80% of prescribed dose) were observed in 17/20 patients when CF was used as the boost field. Conclusion: The electron field determined from clinical scar underestimates the tumor bed in superior-inferior direction significantly and thereby underdosing the tissue at risk. The electron field obtained from surgical clips alone dose not cover the entire scar properly As a consequence, our technique, which combines the surgical clips and clinical scars in determining electron boost field, was proved to be effective in minimizing the geographical miss as well as normal tissue complications.