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11.

Purpose

Premature ejaculation (PE) and erectile dysfunction (ED) are both frequent diseases with several questions about the aetiological factors for these disorders. Lumbar disc herniation (LDH), which can cause both neurological and physiological impairments, may be a causative reason. We prospectively tried to evaluate the presence of PE and ED in patients with LDH and identify the effect of both surgical and physical therapy treatments for LDH on PE and ED.

Methods

A total of 50 patients with LDH and a corresponding control group without LDH at an age of 18–50 years were included in the study. Both PE and ED were evaluated with premature ejaculation diagnostic tool (PEDT) and International Index of Erectile Function. Mean intravaginal ejaculatory latency time (IELT) was calculated at their 5 consecutive intercourse. Physical therapy or microdiscectomy was performed according to indication. After 6 months of follow-up, patients in treatment group were re-evaluated for PE and ED.

Results

Mean age of study and control group was 34.1 ± 3.3 and 34.2 ± 4.0 years, respectively (p = 0.979). In LDH group, IELT was <1 min in 12 (24 %), 1–2 (16 %) min in 8, 2–3 min in 7 (14 %), 3–4 min in 7 (14 %) and 4 or more minutes in 16 (32 %) patients. These numbers were 11 (22 %), 8 (16 %), 5 (10 %), 9 (18 %) and 17 (34 %) in control group, respectively. Mean PEDT score of patients who had IELT < 1 min was 11.9 ± 2.1 and 10.7 ± 2.1 in study and control group, whereas it decreased to 1.0 ± 2.8 and 0.5 ± 1.8 as IELT increased over 4 min, respectively. There were 11 (22 %) patients with ED in LDH group, whereas there were only 2 (4 %) in control group (p = 0.017). Twenty patients with LDH underwent surgery while 30 had been taken into physical therapy. After 6 months, patients with PE significantly decreased in both surgery and physical therapy group (p = 0.025 and p = 0.046). Patients with ED also decreased after treatment, but the numbers were so limited for statistical evaluation.

Conclusion

Although ED was more frequent in patients with LDH, PE was similar in both study and control groups, but the treatment of LDH had positive effects on PE and ED.  相似文献   
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Background: Recent evidence suggests that increased visceral adiposity is a strong independent risk factor for cardiovascular death and all-cause mortality in hemodialysis (HD) patients. Irisin, which is a novel myokine, can play critical roles in diabetes and adiposity. The purpose of our study was to investigate whether serum irisin levels are associated with body mass index, waist circumference (WC), and total fat mass in non-diabetic patients undergoing maintenance HD.

Methods: This cross-sectional study included 108 non-diabetic HD patients and 40 age- and sex-matched apparently healthy subjects. Serum irisin concentrations were determined using an enzyme-linked immunosorbent assay. Body fat composition (TBF-410 Tanita Body Composition Analyzer) was measured and calculated.

Results: Serum irisin levels did not differ between HD patients and the healthy controls (523.50?±?229.32 vs. 511.28?±?259.74, p?=?0.782). Serum irisin levels were associated with age (r?=?0.314; p?=0.006), HOMA-IR (r?=?0.472; p?=?0.003), WC (r?=?0.862; p?r?=?0.614; p?β?=?1.240, p?β?=?0.792, p?=?0.015) were the variables that were significantly associated with irisin concentrations (R2?=?0.684, p?Conclusions: These results suggest that serum irisin levels are related to visceral adiposity in non-diabetic HD patients.  相似文献   
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Evaluating computer-aided detection algorithms   总被引:1,自引:0,他引:1  
Computer-aided detection (CAD) has been attracting extensive research interest during the last two decades. It is recognized that the full potential of CAD can only be realized by improving the performance and robustness of CAD algorithms and this requires good evaluation methodology that would permit CAD designers to optimize their algorithms. Free-response receiver operating characteristic (FROC) curves are widely used to assess CAD performance, however, evaluation rarely proceeds beyond determination of lesion localization fraction (sensitivity) at an arbitrarily selected value of nonlesion localizations (false marks) per image. This work describes a FROC curve fitting procedure that uses a recent model of visual search that serves as a framework for the free-response task. A maximum likelihood procedure for estimating the parameters of the model from free-response data and fitting CAD generated FROC curves was implemented. Procedures were implemented to estimate two figures of merit and associated statistics such as 95% confidence intervals and goodness of fit. One of the figures of merit does not require the arbitrary specification of an operating point at which to evaluate CAD performance. For comparison a related method termed initial detection and candidate analysis was also implemented that is applicable when all suspicious regions are reported. The two methods were tested on seven mammography CAD data sets and both yielded good to excellent fits. The search model approach has the advantage that it can potentially be applied to radiologist generated free-response data where not all suspicious regions are reported, only the ones that are deemed sufficiently suspicious to warrant clinical follow-up. This work represents the first practical application of the search model to an important evaluation problem in diagnostic radiology. Software based on this work is expected to benefit CAD developers working in diverse areas of medical imaging.  相似文献   
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The authors have developed a semiautomatic system for segmentation of a diverse set of lesions in head and neck CT scans. The system takes as input an approximate bounding box, and uses a multistage level set to perform the final segmentation. A data set consisting of 69 lesions marked on 33 scans from 23 patients was used to evaluate the performance of the system. The contours from automatic segmentation were compared to both 2D and 3D gold standard contours manually drawn by three experienced radiologists. Three performance metric measures were used for the comparison. In addition, a radiologist provided quality ratings on a 1 to 10 scale for all of the automatic segmentations. For this pilot study, the authors observed that the differences between the automatic and gold standard contours were larger than the interobserver differences. However, the system performed comparably to the radiologists, achieving an average area intersection ratio of 85.4% compared to an average of 91.2% between two radiologists. The average absolute area error was 21.1% compared to 10.8%, and the average 2D distance was 1.38 mm compared to 0.84 mm between the radiologists. In addition, the quality rating data showed that, despite the very lax assumptions made on the lesion characteristics in designing the system, the automatic contours approximated many of the lesions very well.  相似文献   
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We have developed a computer-aided detection (CAD) system to detect clustered microcalcifications automatically on full-field digital mammograms (FFDMs) and a CAD system for screen-film mammograms (SFMs). The two systems used the same computer vision algorithms but their false positive (FP) classifiers were trained separately with sample images of each modality. In this study, we compared the performance of the CAD systems for detection of clustered microcalcifications on pairs of FFDM and SFM obtained from the same patient. For case-based performance evaluation, the FFDM CAD system achieved detection sensitivities of 70%, 80% and 90% at an average FP cluster rate of 0.07, 0.16 and 0.63 per image, compared with an average FP cluster rate of 0.15, 0.38 and 2.02 per image for the SFM CAD system. The difference was statistically significant with the alternative free-response receiver operating characteristic (AFROC) analysis. When evaluated on data sets negative for microcalcification clusters, the average FP cluster rates of the FFDM CAD system were 0.04, 0.11 and 0.33 per image at detection sensitivity level of 70%, 80% and 90% compared with an average FP cluster rate of 0.08, 0.14 and 0.50 per image for the SFM CAD system. When evaluated for malignant cases only, the difference of the performance of the two CAD systems was not statistically significant with AFROC analysis.  相似文献   
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An 83-year-old man presented with an unusually severe case of rhinophyma. Giant rhinopyhma is very rare in literature. The giant lesion was widely excised using sharp surgical incision and coblation assisted surgery. Using direct coblation to the nasal dorsum may cause edema in the surrounding tissue. There was minimal edema in surrounding tissue using this technique. A full thickness-skin graft was applied after excision. Cosmetic and functional postoperative results were satisfactory.KEY WORDS: Coblation, giant, rhinophyma  相似文献   
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