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81.
82.
Systemic lupus erythematosus pathology reflects autoantibody‐mediated damage due to a failure of B‐lymphocyte tolerance. We previously reported that B‐lymphopenic A/WySnJ mice develop a lupus‐like syndrome and linked this syndrome to the B‐cell maturation defect‐1 (Bcmd‐1) mutant allele of the B‐cell‐activating factor belonging to the TNF family‐receptor (Baffr) gene. Here, we further evaluate the genetic basis for autoimmunity in A/WySnJ mice. We produced B6.Bcmd‐1 and AW.Baffr?/? congenic mice (N5), and compared them with B6.Baffr?/? and A/WySnJ mice with respect to B‐lymphocyte development. Bcmd‐1‐expressing mice had more B cells with greater maturity than Baffr?/? mice regardless of genetic background, indicating that Bcmd‐1 encodes a partially functional BAFF‐R. We also compared these mice for lupus phenotypes to determine whether Bcmd‐1 is necessary and sufficient for disease, or whether the Baffr?/? allele can also cause autoimmunity. The Baffr?/? allele did not lead to autoimmunity on either genetic background. In contrast, the Bcmd‐1 allele was necessary and sufficient for development of low levels of IgM autoantibodies in B6.Bcmd‐1 mice. However, Bcmd‐1 plus unidentified A/WySnJ modifier genes were necessary for development of IgG autoantibodies and renal pathology. We propose that in A/WySnJ mice an excess of BAFF per B cell rescues self‐reactive B cells through a partially functional BAFF‐R in a B‐lymphopenic environment.  相似文献   
83.
84.
This study evaluated the attitudes and practices of the personnel with respect to the prevention of nosocomial infections in a hospital environment. We carried out a qualitative survey of all categories of personnel between July 1998 and March 1999, at the five regional hospitals in Senegal (Thiés, Kaolack, Saint-Louis, Diourbel, and Louga). Data were collected in two ways: using a questionnaire to evaluate knowledge and by observing the attitudes and practices of the personnel. Hands were rarely washed before and after each procedure and surgical washing was often performed in poor conditions. The decontamination of soiled equipment was ineffective. Reusable instruments were washed directly with bare hands or by individuals wearing used surgical gloves. The equipment used for sterilization was dilapidated and unsuitable and the norms for sterilization were seldom respected. Circulation in the region of the operating theatre was disorganized, if not anarchic. The personnel had a high risk of contamination from blood. Biomedical waste was not decontaminated: it was collected poorly and disposed of directly into the environment. None of the sites visited had a program of waste incineration. In conclusion, at the sites visited, there is a high risk of nosocomial contamination during care and the reuse of equipment, for both the staff and the patients treated.  相似文献   
85.
Between May and October 2000, the Regional Health Office of Kolda Region in the south of Senegal, West Africa, reported an epidemic of an unknown illness characterized by thoracic pain, dyspnea and edemas of limb and face. The epidemic covered a radius of approximately 40 km (24 miles) between the districts of Kolda and Sedhiou in Kolda Region. Cases were mostly men whose age ranged between 12 and 60 years old. Investigation revealed that they had been exposed to pesticides distributed by the government to groundnut farmers. The signs and symptoms suggested intoxication with carbamates, carbofurans, and possibly thiram, contained in the pesticides distributed with the groundnut seeds. Government distribution created an excessive use of pesticides in the farms, and consequently an overexposure of the subjects who handled the seeders, especially young males but also a small proportion of women who worked in the groundnut fields. Many of these subjects, not accustomed to handle pesticides, came to overestimate the quantity of product to fill the seeder. It should be noted that the policy of distribution of pesticides in Senegal, which presents risk of poisoning, was not systematically accompanied by sufficient information on the danger of the products and of certain precautions that should be taken during their use.  相似文献   
86.
87.
Opinion statement The gastrointestinal (GI) manifestations of cystic fibrosis (CF) are varied and include pancreatic insufficiency, meconium ileus, distal intestinal obstruction syndrome (DIOS), liver disease, and other less common manifestations. Treatment of pancreatic insufficiency consists of providing appropriate pancreatic enzyme replacement therapy and may include raising duodenal pH to allow for optimal action of these enzymes. Despite a number of pancreatic enzyme replacement products, malabsorption cannot be normalized. Management of DIOS depends on the severity of the symptoms; adequate hydration is very important. Polyethylene glycol solutions are being increasingly used. The precipitating cause of the episode of DIOS should be looked for so future episodes can be prevented. Liver disease is relatively silent and annual monitoring of liver function and status is recommended. Treatment is mainly supportive and the role of ursodeoxycholic acid in the prevention of cirrhosis needs to be better defined. Nutritional status is an important part of management of all GI and liver manifestations of CF. A team approach and the assistance of a registered dietitian are extremely valuable in managing the GI and liver manifestations of CF.  相似文献   
88.
Sheldon DG  Lee FT  Neil NJ  Ryan JA 《Archives of surgery (Chicago, Ill. : 1960)》2002,137(9):1022-6; discussion 1026-8
HYPOTHESIS: The surgical treatment of primary hyperparathyroidism results in an improved health-related quality of life. DESIGN: Prospective cohort analysis of consecutive patients with primary hyperparathyroidism analyzed preoperatively and 1 year postoperatively. SETTING: Academic multispecialty referral clinic. PATIENTS: We prospectively evaluated 74 consecutive patients who underwent parathyroid exploration for primary hyperparathyroidism during a 15-month period. INTERVENTIONS: The Medical Outcomes Study Short-Form Health Survey (SF-36) was administered before consultation with a surgeon. Patients were categorized based on reason for referral as either asymptomatic (group 1; n = 43) or symptomatic (group 2; n = 29). All patients underwent parathyroid exploration and normalization of calcium levels postoperatively. The SF-36 was then re-administered after 1 year. MAIN OUTCOME MEASURES: Statistical analysis of preoperative and postoperative SF-36 scores, and comparisons with national norms. RESULTS: The SF-36 was completed preoperatively and 1 year postoperatively by 72 (97%) of 74 patients. When the results were compared with published national norms, the preoperative population was significantly impaired in 5 of 8 domains, whereas the postoperative one had improved and was nearly indistinguishable from the norm. In 7 of 8 domains, the postoperative scores were significantly improved compared with preoperative scores. Group 1 patients showed significant preoperative impairment in 3 domains and significantly improved in 2, whereas group 2 patients showed significant impairment and improvement in 7 domains. CONCLUSION: The surgical treatment of primary hyperparathyroidism is associated with durable, statistically significant improvements in health-related quality of life.  相似文献   
89.
The inquiry of this study is the beliefs related to the nursing professional in the first decades of this activity in Brazil. The investigation presupposes that some of these beliefs are still current. The objective is to point out the beliefs expressed by Revista Brasileira de Enfermagem (Brazilian Journal of Nursing) in 33 articles, during the period between 1932 (when the journal was created) and 1954. Five notions of the nursing professional were identified through the analyses of the symbology presented on the cover of the periodical--Egyptian mythology; ideal, science and art, inscribed in a triangle. The categories established for nurses were: self-forgetful, heroine, socially committed, mercenary and bad angel. Finally, the study proposes an interpretation to the ideas presented in the triangle.  相似文献   
90.
Previously we reported that vitamin A-deficient (-A) mice had a profound reduction in T helper 2 (Th2) cells, accounting for their depressed T-dependent antibody responses. Providing vitamin A or its active metabolites reversed this defect. The current experiments utilized splenocytes from T cell receptor transgenic mice to investigate how all-trans retinoic acid (atRA) augments Th2 development. These cells were stimulated in vitro in the presence or absence of atRA, with or without exogenous cytokines driving Th1 or Th2 development. Without exogenous cytokines, atRA addition significantly inhibited the interferon (IFN)-gamma response but did not alter the interleukin (IL)-4 response. With Th1 polarizing cytokines, atRA enhanced the IFN-gamma response, with no effect on the IL-4 response. Most importantly, with the Th2 polarizing cytokine IL-4, atRA significantly increased the IL-4 secretion (fivefold) and also increased the Th2 cell frequency twofold. The striking Th2 enhancement was also observed when only antigen-presenting cells were treated with atRA before stimulation of untreated CD4(+) transgenic T cells, but not vice versa. Thus, atRA maximized Th2 cell development in an IL-4-dependent manner, through an effect on antigen-presenting cell function.  相似文献   
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