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71.
It is well established that visual display unit (VDU) operators complain of visual fatigue and visual stress during after-work hours. The present study was divided into two parts. In the first part, standard eye examinations were performed on a group of VDU workers (n = 32) and a control group (n = 15); those subjects who were found to have correct vision (n = 16 and 13, respectively) participated in the second part. The eye examinations revealed that on the average, the VDU workers suffered more than twice as many visual impairments as the controls. In those with correct vision, the near point of accommodation was measured at the beginning of the workday at the start of the week, and at the end of the workday, four days later. In the VDU group, the decrease in accommodation was uniformally distributed between zero and 1.0 diopter, whereas among the non-VDU workers, 77% of the decrease was between zero and 0.25 diopter. The dynamic range of accommodation in the VDU workers on the second examination was smaller than on the first. We conclude that some of the visual stress and visual fatigue that developed at work hindered visual activities after work.  相似文献   
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BACKGROUND: Anastomotic stenosis presents as one of the most common late complications in the postoperative period after bariatric surgery. It is often diagnosed by upper gastrointestinal series (UGIS) and/or upper endoscopy (UE). The aim of this study was to determine whether a correlation exists between the Gastrografin UGIS and UE findings in the determination of gastrojejunal anastomotic strictures after Roux-en-Y gastric bypass (RYGB). METHODS: Between July 2001 and October 2003, all medical records of patients who underwent RYGB at our institution were retrospectively reviewed. The medical records of patients who underwent UE because of symptoms suggestive of gastric outlet obstruction and those of patients who were initially evaluated by Gastrografin UGIS before UE were evaluated further. RESULTS: Of 535 morbidly obese patients who underwent RYGB, 52 (9.7%) had UE and were included in this study. The mean number of UEs performed per patient was 2.67. Of these 52 patients, 30 underwent Gastrografin UGIS before UE. The mean diameter of the anastomosis on the first UE was 5.97 mm and on Gastrografin UGIS was 6.83 mm. A good correlation was found between the Gastrografin UGIS and UE findings using Pearson's correlation coefficient (0.44, P = .02) and single linear regression analysis using the endoscopic diameter as the outcome and radiographic findings as the predictor (beta = 0.27, P = .025, 95% confidence interval 0.30-0.49). CONCLUSION: In our study, the Gastrografin UGIS findings correlated positively with the endoscopic gastrojejunal anastomosis findings in patients with anastomotic stricture who had undergone RYGB.  相似文献   
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Nine months after the residential stage of Koach, participants were asked to evaluate the program's effectiveness. Most of the veterans reported improvement in the areas queried, and especially in social relations, and nearly all of them stated that they would recommend the program to other veterans. The commander-therapists became the major source of help for these veterans following the Koach project, and about half reported that they participated regularly in self-help groups. Most of the participants acquired coping techniques that continued to serve them 9 months after the end of the residential stage of Koach. One of the more important measures of Koach was thought to be the veterans' own evaluations of the project, their assessment of the project's success in achieving its aims, and their satisfaction with it. In this article we will present the subjects' evaluations of treatment effectiveness as expressed in behavioral and emotional changes that they attributed to the treatment.  相似文献   
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Edema disease (ED) of weanling pigs is caused by an infection with Escherichia coli that produces Shiga-like toxin II variant (SLT-IIv). Pathology identical to that caused by ED can be duplicated in pigs that are injected with less than 10 ng of purified SLT-IIv per kg of body weight. Therefore, SLT-IIv was mutated to create an immunoreactive form of the toxin that was significantly reduced in enzymatic activity. Initially, purified SLT-IIv was treated with formaldehyde which abrogated cytotoxic activity. Pigs were vaccinated with the toxoid (100 micrograms) to determine whether a toxoid was a viable vaccine candidate and whether young pigs were capable of mounting an immune response. Although the pigs developed a neutralizing antibody titer (1:128 to 1:512) 28 days postinjection, they also lost weight and developed ED lesions. The deleterious effect of the toxoid appeared to result from residual enzymatic activity or a reversion to a toxic form. An alternative method, site-directed mutagenesis, was employed to consistently reduce the enzymatic activity of SLT-IIv. Glutamate at position 167 of the mature A subunit was replaced by aspartate (E167D), and arginine at position 170 was replaced by lysine (R170K). These mutations reduced cytotoxic activity 10(4)-fold and 10-fold, respectively, while the enzymatic activities were decreased 400-fold and 5-fold, respectively. The activity of a toxin that contained both mutations (SLT-IIvE167D/R170K) closely resembled that of SLT-IIvE167D. When position 167 was replaced by glutamine (E167Q), the cytotoxic activity decreased 10(6)-fold and the enzymatic activity decreased approximately 1,500-fold. Pigs that were vaccinated with purified, mutant toxin designated SLT-IIvE167Q developed a neutralizing antibody titer of 1:512 21 days postinjection, and their tissues were free of ED lesions. These data suggest that SLT-IIvE167Q may represent an effective vaccine against ED.  相似文献   
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The presence of class 1 and class 2 histocompatibility antigens on murine sperm was investigated by flow microfluorometry. Monoclonal anti-H-2Kk (class 1), anti-Iak (specificity 2, class 2) and allo-anti-Iak (class 2) antisera were used in direct or indirect fluorescence labelling experiments to probe the expression of class 1 and class 2 antigens on epididymal mouse spermatozoa. Sperm-specific antibodies were generated by intraperitoneal immunization of both male and female C3H/HeN mice with syngeneic spermatozoa. Sperm-specific antigens were detected in 68-85% of syngeneic mouse sperm and 65-90% of allogeneic mouse sperm examined. Conversely, these antibodies did not stain syngeneic or allogeneic lymphocytes above the background of the negative control. Mouse sperm samples failed to exhibit specific fluorescence above the background of negative control values with antibodies against either class 1 or class 2 MHC antigens. We have established the sensitive, objective and economical assay of sperm membrane antigens with fluorochrome-labelled antibodies by flow microfluorometry. By use of this sensitive and objective technique we have not detected MHC antigens on murine sperm. We conclude that these MHC antigens are not expressed on sperm at a level to be practically detectable.  相似文献   
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