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The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
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OBJECTIVE: To compare the results of open and laparoscopic fundoplication. DESIGN: Nonrandomized controlled study with a 3-year follow-up. PATIENTS AND METHODS: Fifty-seven consecutive patients with erosive reflux esophagitis underwent laparoscopic (30 patients) or open (27 patients) fundoplication. INTERVENTIONS: Interview by an independent person. In addition, 52 patients (91%) underwent postoperative endoscopy, and 38 patients (67%) underwent esophageal 24-hour pH recording. RESULTS: Temporary dysphagia was reported by 20 patients (67%) after laparoscopic and by 11 (41%) after open fundoplication (P = .05). There were no differences between groups concerning incidence of persistent dysphagia (20% vs 18%, respectively) and mild to no reflux symptoms (97% vs 100%, respectively). In addition, bloating (50% vs 63%, respectively) and increased flatus (77% vs 78%, respectively) were equally common. Visual analog scale scores for dysphagia, bloating, and increased flatus were 0.6, 2.4, and 4.3, respectively, in the laparoscopic and 0.6, 3.5, and 3.4, respectively, in the open groups. Normal belching ability was reported by 12 patients (40%) after laparoscopic and by 20 (74%) after open fundoplication (P = .01). Visick grade 1 or 2 was reported by 21 patients (70%) after laparoscopic and by 24 (89%) after open fundoplication (P = .08). Defective fundic wrap was detected in 4 patients (13%) in the laparoscopic and in none in the open group. In addition, abnormal results of 24-hour pH recording were found in 4 patients (22%) after laparoscopic and in 2 (10.5%) after open fundoplication. CONCLUSION: From a functional point of view, both techniques were equally effective except concerning belching ability and temporary dysphagia.  相似文献   
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To compare different MRI sequences for the detection of lesions and the evaluation of response to chemotherapy in patients with diffuse large B‐cell lymphoma (DLBCL), 18 patients with histology‐confirmed DLBCL underwent 3‐T MRI scanning prior to and 1 week after chemotherapy. The MRI sequences included T1‐weighted pre‐ and post‐contrast, T2‐weighted with and without fat suppression, and a single‐shot echo‐planar diffusion‐weighted imaging (DWI) with two b values (0 and 800 s/mm2). Conventional MRI sequence comparisons were performed using the contrast ratio between tumor and normal vertebral body instead of signal intensity. The apparent diffusion coefficient (ADC) of the tumor was measured directly on the parametric ADC map. The tumor volume was used as a reference for the evaluation of chemotherapy response. The mean tumor volume was 374 mL at baseline, and decreased by 65% 1 week after chemotherapy (p < 0.01). The T2‐weighted image with fat suppression showed a significantly higher contrast ratio compared with images from all other conventional MRI sequences, both before and after treatment (p < 0.01, respectively). The contrast ratio of the T2‐weighted image with fat suppression decreased significantly (p < 0.01), and that of the T1‐weighted pre‐contrast image increased significantly (p < 0.01), after treatment. However, there was no correlation between the change in contrast ratio and tumor volume. The mean ADC value was 0.68 × 10–3 mm2/s at baseline; it increased by 89% after chemotherapy (p < 0.001), and the change in ADC value correlated with the change in tumor volume (r = 0.66, p < 0.01). The baseline ADC value also correlated inversely with the percentage change in ADC after treatment (r = ?0.62, p < 0.01). In conclusion, this study indicates that T2‐weighted imaging with fat suppression is the best conventional sequence for the detection of lesions and evaluation of the efficacy of chemotherapy in DLBCL. DWI with ADC mapping is an imaging modality with both diagnostic and prognostic value that could complement conventional MRI. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Frequency of hereditary nonpolyposis colorectal cancer   总被引:10,自引:0,他引:10  
PURPOSE: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant cancer syndrome characterized by early onset of colorectal carcinomas (CRC). Recently, two HNPCC genes have been mapped and cloned, one in the short arm of chromosome 2 and another in the short arm of chromosome 3. There has been a major controversy about the frequency of HNPCC. The few estimates available have been based on series selected by age or series representing local area. The purpose of the present study was to design a nonselected, prospective, multicenter study, taking into account the family background and other risk factors of CRC. METHODS: The proportion of HNPCC of all (N=406) CRC cases was evaluated in a prospective multicenter study. Family history and other risk factors were investigated over a 12-month period for all new CRC patients in ten hospitals. These cases constituted 23 percent of all CRCs diagnosed in Finland during the study period. RESULTS: Three (0.7 percent) cases of verified and seven (1.7 percent) cases of suspected HNPCC were identified, following the evaluation of all families with features indicative of susceptibility to cancer. The proportion of identifiable risk factors of CRC was 5.8–7.5 percent (HNPCC, 0.7-2.4 percent; previous CRC, 3.4 percent; ulcerative colitis, 1.0 percent; familial adenomatous polyposis coli, 0.7 percent). CONCLUSION. This prospective multicenter study revealed that the frequency of hereditary colorectal cancer is lower than in some previous studies, when diagnosis is based on extensive pedigree analysis. This result with recent findings of common ancestral founding mutation in Finnish HNPCC families indicates that there may be geographic differences in the occurrence of HNPCC. However, this does not change the fact that identification of HNPCC—perhaps one of the most common inherited diseases identified in humans—has become a question of vital importance now when diagnosis of the syndrome and largescale screening of gene carriers using specific tests are on the horizon.Supported by grants from the Finnish Cancer Society, the Finnish Foundation for Gastroenterological Research, the Sigrid Juselius Foundation, and the Academy of Finland, Helsinki, Finland.  相似文献   
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M Leidenius  I Kellokumpu  A Husa  M Riihel    P Sipponen 《Gut》1991,32(12):1521-1525
From 1976 to 1989 a total of 66 patients with longstanding ulcerative colitis were entered in a colonoscopic surveillance programme in order to detect dysplasia. Thirty patients had extensive or total ulcerative colitis and 36 left sided colitis. The median duration of the disease at the end of the follow up was 15.0 years. Altogether 182 colonoscopies (2.8 per patient), each involving approximately 20 biopsies from different sites of the colon, were performed. In the total or extensive colitis group, five patients had low grade and one patient had high grade dysplasia. In the left sided colitis group, three patients had low grade dysplasia. In three patients low grade dysplasia was detected in a macroscopic lesion or mass of colonic mucosa. Sixty per cent of the dysplasia specimens were from the right colon. The incidence of dysplasia was higher in patients with extensive colitis and increased with the duration of the disease. None of the patients have so far developed colorectal carcinoma. Our results indicate that a colonoscopic surveillance programme is a safe alternative to prophylactic colectomy in longstanding ulcerative colitis.  相似文献   
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目的:肺癌分期与肿瘤直径的关系已被证实是一个预后指标,因此被纳入1986年肺癌分类的国际系统。近年来由于CT飞速发展,人们可以诊断出更小的肺癌,于是有人提倡对肺癌Ⅰ期进一步分期,即根据肿瘤直径小于还是大于30mm,将无确切远处淋巴结转移的病例(Ⅰ期病例)细分为Ⅰa和Ⅰb期。在诊断无症状(即潜伏)的肺癌时,CT普查的开展使人们考虑肿瘤大小的预后价值。在此我们对CT普查诊断的无症状潜伏型肺癌作了分期与大小关系的报道。  相似文献   
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Technical features of laparoscopic rectopexy include complete rectal mobilization without division of the lateral stalks to avoid parasympathetic denervation and postoperative problems with defecation. Suture rectopexy is equally effective as posterior mesh rectopexy in preventing recurrences and eliminates the use of foreign material which is sometimes associated with intense fibrosis, sepsis and increased constipation. According to two randomised studies constipation seems to be less after resection rectopexy than suture or posterior mesh rectopexy alone perhaps by eliminating possible kinking at the rectosigmoid region by falling of the redundant sigmoid colon in the pouch of Douglas. Randomized studies are, however, needed to validate the need for colonic resection and to determine its optimal extent in patients who suffer from rectal prolapse, constipation and slow transit.  相似文献   
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