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31.
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
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33.
Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator. 相似文献
34.
Performance standards for toric soft contact lenses. 总被引:1,自引:0,他引:1
Jacqueline Tan Eric Papas Nicole Carnt Isabelle Jalbert Cheryl Skotnitsky Maki Shiobara Edward Lum Brien Holden 《Optometry and vision science》2007,84(5):422-428
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
35.
36.
Acute Cellular Rejection with CD20-Positive Lymphoid Clusters in Kidney Transplant Patients Following Lymphocyte Depletion 总被引:1,自引:0,他引:1
L. K. Kayler F. G. Lakkis C. Morgan A. Basu D. Blisard H. P. Tan J. McCauley C. Wu R. Shapiro P. S. Randhawa 《American journal of transplantation》2007,7(4):949-954
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
37.
目的探讨肾动脉狭窄支架植入术的临床疗效.方法1997年1月~2004年12月,我院行支架介入治疗肾动脉狭窄27例.对27例术前、术后及随访期内血压、肾功能以及生活质量进行评估,并与同期单纯药物治疗肾动脉狭窄27例进行比较.结果介入组27例植入支架40枚,手术成功24例(88.9%,24/27),失败3例(11.1%,3/27),手术并发症5例(18.5%,5/27).术后在血压下降(包括收缩压舒张压)肌酐下降,肾小球滤过率增加方面,介入组获益率明显优于药物组,两组比较差异均有显著性,术后随访6个月~8年6个月,中位数为1年9个月,介入组有19例能比较健康的生活和工作,药物组仅12例能维持生活和工作.结论支架介入治疗较单纯药物治疗肾动脉狭窄疗效显著. 相似文献
38.
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
39.
Qiang Tan Rudolf Steiner Simon P Hoerstrup Walter Weder 《European journal of cardio-thoracic surgery》2006,30(5):782-786
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
40.
目的 :探讨系统性红斑狼疮 (SLE)女性患者血清肿瘤标志物CA12 5 ,CA199含量变化及临床意义。方法 :用化学发光法测定 30例正常女性和 38例SLE女性患者血清中CA12 5 ,CA199含量。结果 :正常组CA12 5含量为 11.14± 6 .4 8U/ml,CA199含量为 3.75± 2 .89U/ml;SLE组CA12 5 ,CA199分别为 2 2 .5 6± 2 0 .4 6U/ml,9.5 7± 9.34U/ml。SLE患者CA12 5 ,CA199阳性率分别为 2 1.1% ,7.89%。结论 :SLE患者血清CAl2 5 ,CA199含量较正常组增高 (P <0 .0 5 )。CA12 5 ,CA199在SLE女性患者中可出现阳性 ,对临床诊断SLE有一定价值。 相似文献