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51.
Total motile sperm count is an important parameter for predicting the probability of natural pregnancy. We have externally validated the Samplaski's post-varicocele repair semen analysis nomogram to confirm the predictive accuracy of total motile sperm count. A total of 300 patients who had undergone varicocelectomy between July 2016 and July 2019 from 4 treatment centres were included in this validation cohort study. The predictive performance of the externally validated nomogram was revealed by applying the Pearson correlation coefficient (R = 0.328; 95% confidence interval (CI) 0.220–0.435; p < .001). Compared to Samplaski's nomogram result (R = 0.581; 95% CI 0.186–0.729), our study also revealed a statistically significant rate. However, it had a relatively lower correlation coefficient rate. Notably, the predicted total motile sperm count was lower than the observed post-varicocelectomy total motile sperm count. The calibration plot revealed that the discrepancy between the predicted and observed total motile sperm count was plausible. However, it had low explanatory power in this nomogram model. This validation study demonstrates that the post-varicocele repair Samplaski's nomogram predicts a relatively lower total motile sperm count than the observed count.  相似文献   
52.
53.

Objectives

Measurement of the incidence of the human immunodeficiency virus (HIV) is very important for epidemiological studies. Here, we determined the recency period with the AxSYM avidity assay and the BED-capture enzyme immunoassay (BED-CEIA) in Korean seroconverters.

Methods

Two hundred longitudinal specimens from 81 seroconverters with incident HIV infections that had been collected at the Korea National Institute of Health were subjected to the AxSYM avidity assay (cutoff = 0.8) and BED-CEIA (cutoff = 0.8). The statistical method used to estimate the recency period in recent HIV infections was nonparametric survival analyses. Sensitivity and specificity were calculated for 10-day increments from 120 days to 230 days to determine the recency period.

Results

The mean recency period of the avidity assay and BED-CEIA using a survival method was 158 days [95% confidence interval (CI), 135–181 days] and 189 days (95% CI, 170–208 days), respectively. Based on the use of sensitivity and specificity, the mean recency period for the avidity assay and BED-CEIA was 150 days and 200 days, respectively.

Conclusion

We determined the recency period to estimate HIV incidence in Korea. These data showed that the nonparametric survival analysis often led to shorter recency periods than analysis of sensitivity and specificity as a new method. These findings suggest that more data from seroconverters and other methodologies are needed to determine the recency period for estimating HIV incidence.  相似文献   
54.
55.
During April 2011–March 2012, we retrospectively reviewed medical records for South Korea soldiers to assess the etiology and epidemiology of acute viral lower respiratory tract infections. Adenovirus was the most commonly identified virus (63.2%) and the most common cause of pneumonia (79.3%) and hospitalization (76.6%); 3 soldiers died of adenovirus-related illness.  相似文献   
56.
57.

Objective

Excessive worry about minor matters and a state in which this worry is experienced as uncontrollable are known to be key symptoms of generalized anxiety disorder (GAD). Given the importance of pathological worry in GAD, the need for psychometrically sound measures of this construct has increased. The purpose of this study was to investigate the usefulness of the Korean version of Penn State Worry Questionnaire (K-PSWQ) for screening GAD.

Methods

Two hundred and forty six patients were initially screened, from which 102 GAD patients and 118 patients with anxiety disorder not otherwise specified (anxiety disorder NOS) were finally enrolled. Patients were diagnosed by a structured clinical interview for the DSM-IV Axis I. We also enrolled 114 control subjects who had no medical or psychiatric history. Pathological worry in both patients and control subjects were assessed at baseline using the PSWQ and we estimated optimal cutoff score by the receiver operating characteristic (ROC) analysis.

Results

We found that in the first ROC analysis, a score of 53 could simultaneously optimize sensitivity and specificity in order to discriminate GAD patients from control subjects. From the second receiver operating characteristic analysis, when both sensitivity and specificity were optimized, we can suggest a score of 61 as being the cutoff for differentiating GAD patients from patients with anxiety disorder NOS.

Conclusion

The Korean version of PSWQ is a useful method for screening GAD patients, although ethnic and cultural differences may affect the cutoff score of PSWQ for GAD.  相似文献   
58.

Background

This study investigated the effects of total knee arthroplasty (TKA) on bone mineral density (BMD) of the proximal femur in patients who underwent the procedure.

Methods

Forty-eight patients scheduled to undergo unilateral TKA because of primary knee osteoarthritis were included in this study, which was conducted at a medical center between October 2006 and October 2009. In these 48 patients, 96 hips were evaluated. Measurement of BMD was performed preoperatively and one month, three months, six months, and one year after unilateral TKA. Repeated measured analysis of variance and paired t-tests for comparison of two repeated samples were used to compare differences between time points (preoperation, one, three, six, and 12 months) and between the operative and nonoperative sides.

Results

Preoperatively, BMD of the femoral neck, trochanter, and total hip on the operative side were lower than on the nonoperative side; however, there was no statistical difference. BMD of both femoral neck areas was significantly lower than preoperative BMD at one month and three months after TKA. BMD of both trochanter areas was significantly lower than preoperative BMD at one month and three months after TKA. BMD of both total hips was significantly lower than preoperative BMD at three months after TKA. However, no statistical differences of changes in BMD were observed between the operative and nonoperative sides at each measurement time.

Conclusions

According to our results, TKA was found to affect both proximal femurs during the acute period. However, TKA did not affect a change in BMD of the proximal femur during one year postoperative.  相似文献   
59.
60.

Background

Remodeling of the extracellular matrix (ECM) of adipose tissue is regarded as part of the pathophysiology of obesity. Secreted protein acidic and rich in cysteine (SPARC) was the first ECM protein described in adipose tissue. Matrix metalloproteinases (MMPs) also play a role in ECM remodeling, and MMP-2 and MMP-9 may be associated with abnormal ECM metabolism. Here, we investigated changes in serum SPARC, MMP-2, and MMP-9 concentrations after bariatric surgery in obese adults.

Methods

We recruited 34 obese patients who were scheduled to undergo bariatric surgery for weight loss. We analyzed changes in serum SPARC, MMP-2, and MMP-9 concentrations before and 9 months after bariatric surgery and any associations between changes in SPARC, MMP-2, and MMP-9 concentrations and obesity-related parameters.

Results

Serum leptin levels significantly decreased, and the serum adiponectin level significantly increased after bariatric surgery. The serum SPARC concentration decreased significantly from 165.0?±?18.2 to 68.7?±?6.7 ng/mL (p?<?0.001), and the MMP-2 concentration also decreased significantly from 262.2?±?15.2 to 235.9?±?10.5 ng/mL (p?<?0.001). Changes in the serum SPARC concentration were significantly correlated with HOMA-IR changes, and changes in the serum MMP-9 concentration were found to inversely correlate with serum adiponectin changes.

Conclusion

These findings show that significant decreases in serum SPARC and MMP-2 concentrations occur after bariatric surgery. Our results thus suggest that weight loss via bariatric surgery could alter the ECM environment, and that these changes are related to certain metabolic changes.  相似文献   
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