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31.
Atherosclerosis is by far the leading cause of mortality and morbidity in patients with end stage renal disease undergoing chronic hemodialysis (HD). Vascular endothelial cell adhesion molecules like the intercellular adhesion molecule-1 (ICAM-1) and the vascular cell adhesion molecule-1 (VCAM-1) are involved in the pathogenesis of atherosclerosis. Their soluble forms (sICAM-1, sVCAM-1) are considered potential serum markers of endothelial activation and atherosclerosis. The aim of this study was to clarify the influence of the HD procedure on the levels of sICAM-1 and sVCAM-1 in patients with end stage renal disease. We evaluated 35 clinically stable patients (18 males, 17 females, mean age 61 +/- 12) on chronic HD treatment. Diabetes mellitus coexisted in eight patients and arterial hypertension in 23 patients. Blood was drawn before, every hour during, and after a single HD session in each patient. Low-flux cuprophane dialyzers (GFS 12, Gambro, Lund, Sweden) were used in 22 and high-flux polysulfone dialyzers (Hemoflow F 60S, Fresenius, Oberursel, Germany) in 13 cases. At 30 min into the HD session (n=31, 20 low-flux HD, 11 high-flux HD) blood was drawn simultaneously from the entrance and the exit line of the dialyzer. From all these samples, serum concentrations of sICAM-1 and sVCAM-1 were determined by commercially available enzyme immunoassays (ELISA, R&D Systems, Minneapolis, USA). Results were corrected according to hemoconcentration, where appropriate. Plasma levels of sVCAM-1 were elevated in patients with end stage renal disease before the beginning of the dialysis session when compared to healthy controls (1449 +/- 497 ng/mL vs. 691 +/- 118 ng/mL). On the contrary, such an elevation was not found in the case of sICAM-1 (231 +/- 58.5 ng/mL vs. 236.4 +/- 96.8 ng/mL in healthy controls). These levels remained stable in all measurements throughout the dialysis procedure. Furthermore, serum sICAM-1 and sVCAM-1 levels remained unaltered after the passage of the dialyzer. The levels of sICAM-1 and sVCAM-1 were not influenced by the existence of diabetes mellitus, hypertension, or by the utilization of biocompatible, high flux dialyzers. Our study confirms that in chronic HD patients serum levels for sVCAM-1 are elevated. The levels of adhesion molecules are not affected by the HD procedure. These findings probably can be attributed to a decreased renal clearance or catabolism of sICAM-1 and sVCAM-1 and to the different sources of the two molecules. Neither coexisting diabetes mellitus nor arterial hypertension influences the circulating levels of these adhesion molecules. The functional role of sVCAM-1 and sICAM-1, the exact renal contribution to their metabolism, and their role as markers of atherosclerosis in chronic renal disease need further evaluation.  相似文献   
32.
OBJECTIVE: We sought to assess the accuracy of endometrial thickness measurement in the diagnosis of endometrial cancer in patients with obesity, diabetes, and hypertension and to evaluate whether patient characteristics influence endometrial thickness irrespective of the final diagnosis. METHODS: This was a prospective study of women not using hormone replacement therapy who presented with postmenopausal bleeding at 8 hospitals in The Netherlands. All women underwent transvaginal ultrasonography and, in the event that the endometrial thickness (double layer) was more than 4 mm, subsequent endometrial sampling. The performance of endometrial thickness measurement in the diagnosis of atypical hyperplasia and endometrial cancer was evaluated in subgroups of patients with diabetes, hypertension, and obesity by using receiver operating characteristic analysis. RESULTS: Overall, we included 594 consecutive women, of whom 62 (10%) had endometrial carcinoma and 6 (1%) had atypical hyperplasia. In these women, transvaginal ultrasonography had an area under the receiver operating characteristic curve of 0.87 (standard error [SE] 0.03). In the absence of (pre)malignancy, women with diabetes or obesity were found to have thicker endometria than women without these risk factors, whereas in women with a (pre)malignancy, this difference was not present. The area under the receiver operating characteristic curve decreased to 0.74 (SE 0.05) and 0.75 (SE 0.07) in diabetic women and obese women, respectively. The presence or absence of hypertension had no impact on the accuracy of transvaginal ultrasonography. CONCLUSION: In view of the decreased diagnostic accuracy in diabetic women and obese women, the clinical value of transvaginal endometrial thickness measurement in these women is questionable.  相似文献   
33.
Background: The technique of laparoscopic adjustable gastric banding (LAGB), although relatively well standardized, has some "weak points". Methods: We analysed the experience of 2 German university clinics in order to suggest technical alternatives that can be helpful in difficult situations. Results: Between April 1997 and May 2002 115 patients in Cologne (87 females, 28 males) with median BMI 49.5 kg/m2 and mean age 39 years (19-54), and 112 patients in Mainz (91 females, 21 males) with median BMI 48 kg/m2 and mean age 35 years (18-57) underwent LAGB, using the Lap-Band?. LAGB was performed through 5 ports (3 10-mm, 1 18-mm, and 1 5-mm in Cologne and 4 10-mm and 1 18-mm port in Mainz). The pars flaccida technique by means of a fanshaped Endo-Retractor was used in both clinics. Mean duration of follow-up was 3.2 years (SD 1.0) in the Cologne group with complete investigation in all except 4 patients. In the Mainz group, mean duration of follow-up was 2.7 years (SD 1.0) with complete investigation in all except 9 patients. Conclusions: Some technical aspects such as induction of pneumoperitoneum, band position, band fixation, band malposition and port-related complications are discussed.  相似文献   
34.
Background. The stability of the lower abdominal wall may play a considerable role in the development of inguinal hernia. Therefore, the strength of the individual wall layers needs to be quantified. Despite numerous advances in hernia repair, comparatively few systematic biomechanic and morphometric analyses have been performed. Our aim was to establish and apply a standardised procedure for testing the abdominal wall layers stability. Methods. After dissecting the abdominal walls of 16 cadavers into separate layers, we used a spherical punch and a force transducer to investigate the forces necessary to foraminate the layer. In addition, maximum tensile-strength and suction tests and histologic morphometry were performed. Results. The transversalis fascia was torn up on an average of 10.5 N, the peritoneum including pre- and subperitoneal tissue on 46.6 N, the aponeurosis of obliquus internus abdominis muscle on 51.7 N, and the aponeurosis of obliquus externus abdominis muscle on 92.6 N. Tensile tests of tissue strips obtained from defined areas showed comparable results. In contrast, surgical mesh revealed values between 60 and 150 N in punching tests. Left-right comparisons, as well as comparisons of the individual areas, revealed considerable intra- and inter-individual differences. Conclusions. Biological hernia repair should focus on a reinforcement of the tissue layers with the highest biomechanic stability. Reinforcement of the transversal fascia must be questioned according to our results of poor mechanical resistance.  相似文献   
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Does mode of hysterectomy influence micturition and defecation?   总被引:7,自引:0,他引:7  
OBJECTIVE: Hysterectomy may affect bladder and bowel function. A retrospective study was performed to compare the prevalence of micturition and defecation symptoms between different modes of hysterectomy. METHODS: All pre-operatively asymptomatic patients, with uteral size < or =10 cm, who underwent hysterectomy between 1988 and 1997 were interviewed about the prevalence of micturition and defecation symptoms and the experienced physical and emotional limitations of these symptoms. Using logistic regression analysis, odds ratios (OR) were calculated for all symptoms of which the prevalence between modes of hysterectomy differed more than 10%. These odds ratios were adjusted for differences in other prognostic factors. RESULTS: Vaginal hysterectomy was performed on 68 patients, total abdominal hysterectomy on 109 patients and subtotal abdominal hysterectomy on 50 patients. An increased prevalence of urge incontinence (adjusted OR 1.5 (95% CI 0.8-3.1)) and feeling of incomplete evacuation (adjusted OR 1.9 (95% CI 1.0-4.0)) was observed among patients who had undergone vaginal hysterectomy as compared to patients who had undergone total abdominal hysterectomy. The prevalence of urge incontinence (adjusted OR 1.8 (95% CI 0.8-4.2)) and difficulty emptying the rectum (adjusted OR 1.8 (95% CI 0.7-4.4)) was higher among patients who had undergone vaginal hysterectomy than among patients who had undergone subtotal abdominal hysterectomy. Statistically significant odds ratios were not observed. Relevant differences in physical and emotional limitations related to micturition and defecation symptoms were not observed between groups. CONCLUSION: Our results suggest that technique of hysterectomy may influence the prevalence of micturition and defecation symptoms following hysterectomy.  相似文献   
40.
Background This study examined the effect of anterior partial fundoplication on reflux symptoms and dysphagia in gastroesophageal reflux disease.Patients and methods Perioperative results in 249 patients were evaluated retrospectively for 93 conventional and prospectively for 156 laparoscopic procedures. The patients were followed up by standardized questionnaire. Median clinical follow-up period was 9 months (range 6–44) after laparoscopic and 88 months (range 15–194) following partial open fundoplication.Results The median operating time was 58 and 115 min for laparoscopic and open partial fundoplication. Intraoperative complications were rare (1%) for both approaches. After introduction of the laparoscopic procedure the morbidity rate was reduced (mean 3.2% vs. 1.3%) at a shorter postoperative hospital stay (10 vs. 5 days). No reflux symptoms were found in 71.4% patients after conventional and in 69% after laparoscopic partial fundoplication, dysphagia did not develop in 86% and 85%, respectively, and 66% and 82% received no medications. Among the patients with reflux symptoms 6.5% and 0.9% underwent revision surgery. Satisfaction with the surgical outcome was expressed by 78% and 85% of patients, respectively.Conclusions Anterior partial fundoplication achieves effective medium- and long-term control of reflux symptoms. Technically easy to perform and associated with few complications, the procedure is superior to fundoplication with respect to the development of postoperative dysphagia and therefore represents a viable alternative to fundoplication.  相似文献   
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