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161.
The significance of anticardiolipin antibodies (ACAs) prior to renal transplantation is unclear. We studied a cohort of 337 patients who underwent renal transplantation from 1996 to 2001. Follow-up continued until allograft loss, patient death or 31 December 2002. The primary outcome was a composite endpoint of death-censored allograft loss or a 25% reduction in estimated glomerular filtration rate (GFR) from 1-month post-transplant. Secondary outcomes were allograft loss, a 25% reduction in GFR, acute rejection and creatinine at 1 year. IgG and IgM ACA titers were positive (> or =15) in 18.1% of recipients. There were no significant differences at baseline between recipients, except coumadin therapy in those with positive ACA titers (20% vs. 7.4%). Post-transplant, there was no increase in the primary outcome in ACA-positive patients, even after adjustment for anticoagulation with coumadin (HR = 1.42 [0.68, 2.96]). There was no difference in secondary outcomes between those with or without positive titers. Two of five patients with very high titers (>50) who were not anticoagulated had early graft loss. A positive ACA titer prior to kidney transplantation was not associated with inferior renal outcomes after transplantation, although more research is required to address the prognostic significance of very high ACA titers.  相似文献   
162.
对管碟法测定Nisin效价的条件进行了研究,考察了几个参数的影响,得出了Nisin测定的最佳条件:90mm培养皿中培养基加量为15mL,Na2HPO4·12H2O质量浓度1g/dL,菌悬液浓度109CFU/mL,琼脂质量浓度1g/dL,培养基pH值7.0,牛津杯中样品加液量100μL.在此条件下,Nisin效价在5~100IU/mL,其对数值与抑菌圈直径有较好的线性关系.  相似文献   
163.
甲醛固定源同种异体骨移植材料的体外实验研究   总被引:5,自引:0,他引:5  
OBJECTIVE: To conduct an in vitro study to assess the preliminary possibility of using formalin-fixed, instead of fresh, human bone tissues for allografting. METHODS: Fresh cadaveric bone tissues were fixed by formalin for more than 6 months and dissected into 5 mmx5 mmx5 mm pieces and 5 mmx5 mmx40 mm sticks, followed by chemical treatments to prepare the allograft bone materials. When alls treatments were completed, the bone grafts were centrifuged and their properties and cellular compatibility assessed in comparison with the currently used bone grafts clinically. RESULTS: The residual formaldehyde of the fixed allograft bone material was much below the controlled level and no significant differences were noted between the bone graft materials tested in regard to the chemical and mechanical properties and biocompatibility. CONCLUSION: This material we have prepared may meet the clinical demands for bone grafting, with good biocompatibility and less chance for infection by pathological agents.  相似文献   
164.
To examine the effect of mating behavior on luteinizing hormone-releasing hormone (LHRH) release, intact New Zealand female rabbits were implanted with push-pull cannulae (PPC) aimed at the tuberal region of the hypothalamus and perfused with modified Krebs-Ringer phosphate medium at 11-13 microliters/min. In the mating experiments, does (n = 10) were initially perfused for a control period of 60-170 min followed by a mating period (100-160 min) which included the introduction of the male rabbit for an average time period of 30 min. Two groups of LHRH release patterns were observed: positive and negative responders. In the positive LHRH responders (n = 5), a clear rapid increase in LHRH release following mounting by the male occurred with a significant increase in the mean LHRH release (1.83 +/- 0.33 to 3.27 +/- 0.80 pg/10 min, p less than 0.040), in the mean LHRH amplitude (1.97 +/- 0.46 to 4.33 +/- 1.29 pg, p less than 0.022) and in the amplitude of the largest LHRH pulse (2.13 +/- 0.43 to 7.58 +/- 3.65 pg, p less than 0.022). In the negative LHRH responders (n = 5), no changes in LHRH release were detected although all rabbits ovulated, with some becoming pregnant. It appears from histological analysis that the difference between these two patterns of responses following mating are due to different cannula placements. In the positive responders, the tip of the PPC was localized in the tuberal region whereas in the negative responders, the placements were more dorsal and, in some cases, anterior.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
165.
本文对42例喉咽癌手术及放疗后患者甲状腺功能的变化的初步探讨表明:在治疗结束后不同时间内有57.1%的患者T4降低及(或)TSH升高,其中放疗结合甲状腺部分切除者其发生率高达73.9%,而未行甲状腺部分切除者仅38.5%,两者呈显著差异(P=0.03)。术前或术后放疗对甲状腺功能影响较小,亦无明显差异。发生时间在治疗结束后2年内尤其在1年左右为多见。  相似文献   
166.
Laryngeal tuberculosis: a review of 26 cases.   总被引:2,自引:0,他引:2  
OBJECTIVES: To review the clinical characteristics of laryngeal tuberculosis. STUDY DESIGN: Retrospective case series. SUBJECTS AND METHODS: Medical records of 26 histopathology-confirmed cases in a tertiary medical center from 1992 to 2006. RESULTS: The female patients were significantly younger than male patients. Hoarseness is the most common symptom (84.6%) because true vocal fold is most commonly involved (80.8%). Infection usually involves unilateral (66.7%) and right-side larynx but multiple subsites of the larynx (57.7%). The appearance of the affected larynx may have mixed features and change before diagnosis. Laryngeal tuberculosis is usually misdiagnosed as laryngeal cancer, especially in patients with malignant signs such as enlarged cervical lymph nodes and vocal fold immobility. Chest film is better than sputum examinations for screening. CONCLUSION: We should be especially alert about TB infection when facing young female patients with unusual laryngeal lesions. Extensive laser excision before diagnosis should be avoided because after antituberculous treatment, prognosis is usually good and vocal fold immobility could be reversible.  相似文献   
167.
L-asparaginase, an effective antileukemia and antilymphoma agent, is toxic to many organ systems. We report a case of ureteral obstruction caused by L-asparaginase via the inflammatory complication of acute pancreatitis. The patient was an 11-year-old boy with acute lymphoblastic leukemia. Six days after completing a 4-week induction therapy containing 9 doses of L-asparaginase, severe left abdominal pain developed. Abdominal computed tomography showed phlegmon formation anterior to the pancreatic head and in the left posterior pararenal space. The strands of inflammatory soft tissues encased the upper third of the left ureter, causing left hydroureter and left hydronephrosis. The ureteral obstruction resolved after insertion of a double-J catheter that remained in place for 66 days. This case suggests that L-asparaginase may play a role in the pathogenesis of ureteral obstruction in children receiving chemotherapy.  相似文献   
168.
Using a prospective hospital-based registry, 146 patients with transient ischaemic attack (TIA) were compared with 376 patients with minor first-ever ischaemic stroke with respect to the 3-month risk of subsequent vascular events, in order to clarify the distinctions between the disease entities. All patients were enrolled within 48 h of onset. The risk factor distribution for the two groups was comparable, except that the TIA patients had more previous TIAs. Large artery atherosclerosis (34%) and small vessel occlusion (32%) were the main aetiologies in the TIA group, whereas small vessel occlusion (49%) was the major cause in the stroke group. The 3-month risk of combined endpoints of stroke, myocardial infarction, and vascular death for TIA patients was higher than that for the minor stroke group (15.1% vs. 3.2%; hazard ratio 4.6, 95% confidence interval 2.3-9.3 in multivariate analysis). Large artery atherosclerosis and male sex were the other significant predictors. TIA may demand more urgent management than minor stroke. The fact that aetiology is a predictor, highlights the need for rapid diagnostic tests to establish pathogenesis.  相似文献   
169.
170.
研究Cu~(2+)在稀氨水介质中催化H_2O_2氧化苯基荧光酮褪色反应及影响反应速率的动力学因素。据此建立催化动力学法测定痕量Cu~(2+)的新方法,其灵敏度为5.0×10~(-11)mol/L,测定范围为(0~2.5)×10~(-7)mol/L。操作简便、快速。该法可用于人体血请中痕量铜的测定。  相似文献   
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