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41.
In view of the ability of ketones to partially replace glucose as an alternative fuel in the brain, the potential protective effects of diet-induced ketosis were examined in male NEDH rats with hypoglycaemia due to a serially transplantable radiation-induced insulinoma. Ketosis was induced by daily oral administration of medium chain triglycerides to normal rats and to insulinoma-bearing rats 1 day after subcutaneous subscapular implantation of tumours fragments. All rats treated with medium chain triglycerides became ketotic within 72 hours, and plasma 3-hydroxybutyrate concentrations remained 5-10 fold elevated at 24 days. Untreated insulinoma-bearing rats became moderately hyperinsuliaemic and hypoglycaemic by 17 days, with the later manifestation of more marked hyperinsulineamia (21.6 +/- 0.8 ng/ml, mean +/- SEM) severe hypoglycaemia (1.5 +/- 0.1 mmol/l) and death by 24-28 (26 +/- 1) days. Induction and maintenance of hyperketonaemia did not affect the development of hyperinsulineamia, hypoglycaemia or the exaggerated fall of plasma glucose produced by an 8 hour fast in these rats. However by day 21, the severity of hypoglycaemia was greater in insulinoma-bearing rats receiving medium chain triglycerides, culminating in accelerated death by 22-25 (23 +/- 1) days and an accompanying 50% decrease in final tumour weight. These results demonstrate that induction of ketosis in the face of marked hyperinsulinaemia did not afford protection against the profound hypoglycaemia produced by a serially transplantable rat insulinoma.  相似文献   
42.
43.
Performance standards for toric soft contact lenses.   总被引:1,自引:0,他引:1  
PURPOSE: To simplify the clinical assessment of toric soft contact lens (TSCL) on-eye behavior by establishing a set of standard clinical evaluation techniques. The likely performance range expected among the TSCL wearing population was determined for a series of lens designs and acceptable performance standards indicated for each variable. METHODS: Four prism-ballast, two peri-ballast and one dynamic stabilization TSCL designs were each worn by groups of 20 subjects in a nondispensing study. After 20 min of lens wear, lenses were assessed, in right eyes only, for subjective comfort (100-point scale), lens mislocation (degrees deviation from vertical) and rotational recovery after deliberate 30 degrees mislocation (degrees/10 blinks). The percentage of lenses orienting within +/-10 degrees of target orientation (zero rotation) and the variability of orientation (standard deviation of mislocation) were also calculated for each lens group. RESULTS: Based on partitioning of the data distributions for each variable, performance was designated as excellent, acceptable or poor. Corresponding performance cut-offs were determined at > or =90, 89 to 80, and <80 for subjective comfort, < or =+/-6 degrees , +/-7 degrees to 10 degrees , and >+/-10 degrees for mislocation, >10 degrees /10 blinks, 10 degrees to 6 degrees /10 blinks, and <6 degrees /10 blinks for rotational recovery. For groups of wearers the appropriate cut-offs were > or =90%, 89 to 70%, and <70% of lenses orienting within +/-10 degrees of target orientation and <+/-6 degrees , +/-6 degrees to 10 degrees , and >+/-10 degrees for variability of orientation. CONCLUSION: Techniques suitable for the evaluation of TSCL clinical performance have been described and guidelines for the assessment of such lenses established. In the process, we have identified potential performance differences that may relate to variations in TSCL design.  相似文献   
44.
Lymphoid clusters (LC) containing CD20-positive B cells in kidney allografts undergoing acute cellular rejection (ACR) have been identified in small studies as a prognostic factor for glucocorticoid resistance and graft loss. Allograft biopsies obtained during the first episode of ACR in 120 recipients were evaluated for LC, immunostained with CD20 antibody, and correlated with conventional histopathologic criteria, response to treatment and outcome. LC were found in 71 (59%) of the 120 biopsies. All contained CD20 positive B cells that accounted for 5-90% of the LC leukocyte content. The incidence of LC was highest in the patients who had no lymphoid depletion or had been treated with Thymoglobulin preconditioning (79% vs. 75%, respectively) compared to 37% in patients pretreated with Campath (p = 0.0001). Banff 1a/1b ACR were more frequent in the LC-positive than the LC-negative group (96% vs. 80%, respectively; p = 0.0051). With a posttransplant follow-up of 953 +/- 430 days, no significant differences were detected between LC-postitive and LC-negative groups in time to ACR, steroid resistance, serum creatinine and graft loss. CD20+LC did not portend glucocorticoid resistance or worse short to medium term outcomes. CD20+LC may represent a heterogenous collection in which there may be a small still to be fully defined unfavorable subgroup.  相似文献   
45.
付璟 《西南军医》2007,9(4):11-12
目的观察WGLY-801型电脑肝病治疗仪对慢性乙型肝炎的治疗效果。方法随机选取慢性乙型肝炎患者144例,分为治疗组66例,在常规治疗基础上加用肝病治疗仪;对照组78例,采用常规治疗,观察两组治疗效果。治疗三疗程共45天(每疗程15天),观察临床症状、肝功能的动态变化,并对最终效果进行评价。结果经治疗后,两组患者临床症状、肝功能较前均有好转,但治疗组起效快,疗程明显缩短,疗效好,差异有明显统计学意义(p<0.05)。结论肝病治疗仪,操作简单,疗效确切,值得进一步推广应用。  相似文献   
46.
苦参液雾化吸入辅助治疗小儿哮喘   总被引:1,自引:0,他引:1  
目的:观察苦参液雾化吸入辅助治疗小儿哮喘的临床疗效.方法:本组88例,随机分成中西药治疗组及西药对照组,每组44例,对照组常规用抗生素、激素及口服美喘清;治疗组常规用抗生素、激素,并用苦参液雾化吸入.结果:治疗组44例,哮喘症状及体征消失时间均短于对照组(p>0.05).结论:苦参液雾化可作为小儿哮喘的重要辅助治疗方法之一.  相似文献   
47.
目的探讨用游离自体腹白线片修补急性十二指肠溃疡穿孔的应用价值。方法从2006年1月至2006年7月对13例用自体腹白线片修补急性十二指肠溃疡穿孔的病人的临床资料和随访情况进行回顾性分析,其中2例穿孔大于2cm2,平均手术时间60分钟,平均失血量20ml,平均住院天数9±1天。结果游离自体腹白线片修补急性十二指肠溃疡穿孔13例均痊愈出院。随访15天至6个月,无手术并发症。结论本方法操作较简单、安全、效果好,其适应症广,是一种可行的新方法。  相似文献   
48.
Pulmonary thromboembolism is the leading direct cause of maternal deaths in the UK. The majority of deaths occur in the puerperium. Caesarean section has been recognised as a risk factor but there is concern that more attention to thromboprophylaxis after vaginal births is needed. The hospital maternity unit in Dumfries has written guidelines on thromboprophylaxis after vaginal births. This audit assessed the compliance with these guidelines within this maternity unit. The case notes relating to spontaneous vaginal births over a 2-month period (n=148) and instrumental vaginal births over a 7-month period (n=29) were reviewed. Information concerning venous thromboembolism risk and any thromboprophylaxis given was extracted. The audit showed that 9% of spontaneous vaginal births and 62% of instrumental vaginal births required specific thromboprophylaxis. However, only 31% of the spontaneous vaginal births and 22% of the instrumental vaginal births in which thromboprophylaxis was indicated did indeed receive the required treatment. Failure to respond to venous thromboembolism risk factors was common. Measures to increase the awareness of maternity staff to these factors are suggested.  相似文献   
49.
This review tries to summarize the efforts over the past 20 years to construct a tissue-engineered trachea. After illustrating the main technical bottlenecks faced nowadays, we discuss what might be the solutions to these bottlenecks. You may find out why the focus in this research field shifts dramatically from the construction of a tubular cartilage tissue to reepithelialization and revascularization of the prosthesis. In the end we propose a novel concept of 'in vivo bioreactor', defined as the design of a perfusion system inside the scaffold, and explain its potential application in the construction of a tissue-engineered trachea.  相似文献   
50.
妇幼卫生专业毕业生的追踪调查   总被引:1,自引:1,他引:0  
20 0 2年 9~ 1 2月对中山大学公共卫生学院妇幼卫生专业的毕业生及用人单位进行了信函追踪调查。结果表明 :总体而言 ,该系学生思想素质、业务水平、工作能力均较强 ,受到用人单位的一致好评。该系学生保健服务能力是强项 ,体现了“以保健为中心”的办学思想。但同时也发现妇幼系的培养模式、课程设置、教学方法均存在一定问题 ,最突出的是临床动手能力较差 ,其次为社区工作能力、组织管理能力、社交能力相对不足 ,创新能力较差 ,所以教学改革势在必行  相似文献   
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