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101.
One hundred and fifty severely injured patients requiring long-term artificial ventilation were evaluated in a prospective, randomized, double blind study comparing the prophylactic effect of an intravenous immunoglobulin (Sandoglobulin; IGIV) against nosocomial infections with a placebo preparation. The groups were comparable in age, sex, injury pattern, and severity of the trauma. Seventy-six patients received 12 g of Sandoglobulin as a 3% solution on day 0, day 5 and day 12, i.e. a total of 36g. Sandoglobulin significantly reduced the incidence of pneumonia (28 cases in the IGIV group, 43 cases in the placebo group, p=0.0111). This resulted in a reduced therapeutic use of antibiotics. For the occurrence of sepsis (IGIV: 14 cases; placebo 19 cases) and other infections (IGIV: 11 cases; placebo: 10 cases) no significant differences were found. No side effects of the administration of IGIV were observed. IGIV prophylaxis neither reduced the overall death rate nor those deaths caused by infection. On day 5 after administration of the first 12 g of IGIV, the IgG serum concentrations were significantly higher in the Sandoglobulin group (8.41±1.96 mg/ml and 7.42±2.25 mg/ml respectively, p>0.001) whereas later serum samples showed no significant differences.  相似文献   
102.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
103.
目的:实验以移植后3个月、6个月时间超声心动图客观指标评估了自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭的效果和安全性。方法:选择2004—06/2006—06江苏省苏北人民医院心内科自愿接受干细胞移植的7例心肌梗死后心力衰竭患者,平均年龄69岁,心功能Ⅲ-Ⅳ级,左室射血分数〈50%。药物治疗基础上加用自体干细胞冠状动脉内移植治疗的方法,其中2例骨髓干细胞在体外扩增后获得,5例经粒细胞集落刺激因子皮下注射动员自体骨髓干细胞后分离外周血获得干细胞悬液。将采集的干细胞悬液经0ver-the-wire球囊导管中心腔注入梗死相关动脉。观察自体干细胞动员,培养,采集和回输过程中的不良反应。在移植前、移植后3月、6月应用超声心动图评价左室形态和心功能变化,室壁运动积分指数及6min步行距离。结果:7例患者均进入结果分析。移植3个月后,心功能得到改善,超声心动图检查左室收缩期内径及射血分数变化不大,6min步行距离有所提高,但差异无显著性(P〉0.05)。移植6个月后,患者心功能明显改善,超声心动图检查左室收缩期内径及射血分数和室壁运动积分均有明显提高(P〈0.05),6min步行距离也有明显提高(P〈0.05)。整个过程中未出现严重并发症。结论:自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭,6个月时超声心动图客观指标评估能够改善患者心功能,且安全。  相似文献   
104.
BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.  相似文献   
105.
目的:将可注射纳米骨材料与共培养的兔肾血管内皮细胞和兔骨髓间充质干细胞诱导的成骨细胞复合,并构建可注射细胞型纳米组织工程骨,观察它们体外培养的相容性. 方法:实验于2003-09/2004-11在苏州大学附属儿童医院完成.①实验材料:取16周龄雄性新西兰大耳白兔,体质量1.5 kg左右.②实验方法:麻醉后抽取兔骨髓,用淋巴细胞分离液分离出其中的间充质干细胞,在含体积分数为0.15牛血清的RPMI1640液中培养.骨髓间充质干细胞在条件培养基中,7 d后可见细胞变为多边形,碱性磷酸酶和Ⅰ型胶原染色阳性,形成钙结节,表现成骨细胞分化特点.采用三步梯度筛网法,获得肾血管球,5 g/L胶原酶Ⅳ37℃消化15~20 min,离心沉淀获取血管内皮细胞,在含体积分数为0.15小牛血清的M199中培养.③实验评估:免疫组织化学法进行第Ⅷ因子相关抗原鉴定,透射电镜观察细胞浆Weibel-Palade小体,间接免疫荧光法检测CD31、CD34及CD44的表达.将共培养的兔肾血管内皮细胞、成骨细胞与可注射纳米骨材料体外复合培养,进行形态学观察和功能测定. 结果:①在一定培养条件下成功诱导兔骨髓间充质干细胞向成骨细胞分化.②培养的血管内皮细胞免疫组织化学法检测第Ⅷ因子相关抗原阳性,透射电镜观察到细胞浆中的Weibel-Palade小体,间接免疫荧光法检测CD31、CD34表达阳性,CD44阴性.③共培养的兔肾血管内皮细胞、成骨细胞在可注射纳米骨材料上生长、增殖良好,细胞活性和碱性磷酸酶活性未受到影响. 结论:可注射纳米骨材料具有良好的细胞相容性,可作为骨组织工程理想的可注射载体材料.  相似文献   
106.
Cyclosporin nephrotoxicity in heart and lung transplant patients   总被引:1,自引:0,他引:1  
Twenty-two patients with heart, lung or heart and lung transplants maintained on cyclosporin for periods ranging from 3 months to 10 years developed renal insufficiency which was investigated by renal biopsy. The histopathological changes were: (i) severe vascular and glomerular damage due to thrombotic microangiopathy (TM); (ii) a form of focal segmental glomerulosclerosis (FSGS); (iii) glomerular ischaemia. Rather than being separate entities, these changes appeared to represent a spectrum of pathology, some biopsies showing all three forms of glomerular injury. In all cases the glomerular changes were accompanied by arteriolar and arterial pathology, and we identified novel ultrastructural changes in the arteriolar endothelial basal lamina. Tubular atrophy was a consistent feature, the severity of which reflected the severity of the glomerular sclerosis, and which appeared to be a consequence of glomerular loss. Our findings are consistent with the nephrotoxic effects of cyclosporin being mediated chiefly via damage to preglomerular vessels and glomerular capillary endothelium. From an analysis of the clinical aspects of these cases, the effects of cyclosporin appear to be to some extent idiosyncratic, and therefore not entirely preventable, but strict monitoring of blood cyclosporin levels is essential to minimize the risk of permanent renal damage. Monitoring urinary protein in addition to plasma creatinine may detect the onset of FSGS, as proteinuria precedes creatinine elevation.   相似文献   
107.
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic pulmonary infection/inflammation which leads to respiratory failure. The presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has previously been observed in the sera of patients with CF. In view of the known relationship of ANCA with primary vasculitis and of their putative pathogenetic role in these disorders, we studied the presence, specificity and isotype of ANCA and their clinical associations in 66 adult CF patients. None of the 66 CF samples had autoantibodies to the major ANCA antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples contained IgG and 55/66 (83%) IgA, autoantibodies to bactericidal/permeability increasing protein (BPI), a recently characterized ANCA specificity. All the IgA anti-BPI-positive samples were also IgG anti-BPI-positive. The autoantibody specificity was confirmed by inhibition assay and immunoblotting of CF sera against a neutrophil granule preparation. Furthermore, in this cross-sectional study, anti-BPI levels were inversely correlated with the observed reductions in FEV1 and FVC (IgA anti-BPI and FEV1: r = 0.508, <it>p</it> &lt; 0.0001), and both IgG and IgA anti-BPI levels were higher in CF patients with secondary vasculitis (<it>n</it> = 6) than in those without (<it>p</it> &lt; 0.05). ANCA with specificity for BPI were present in the majority of CF sera in this study and autoimmune processes may be associated with the development of pulmonary injury in CF.   相似文献   
108.
109.
Pancreatic beta-cell function was studied in six subjects with mutations in the enzyme glucokinase (GCK) who were found to have elevated fasting and postprandial glucose levels in comparison to six normoglycemic controls. Insulin secretion rates (ISRs) were estimated by deconvolution of peripheral C-peptide values using a two-compartment model and individual C-peptide kinetics obtained after bolus intravenous injections of biosynthetic human C-peptide. First-phase insulin secretory responses to intravenous glucose and insulin secretion rates over a 24-h period on a weight maintenance diet were not different in subjects with GCK mutations and controls. However, the dose-response curve relating glucose and ISR obtained during graded intravenous glucose infusions was shifted to the right in the subjects with GCK mutations and average ISRs over a glucose range between 5 and 9 mM were 61% lower than those in controls. In the controls, the beta cell was most sensitive to an increase in glucose at concentrations between 5.5 and 6.0 mM, whereas in the patients with GCK mutations the point of maximal responsiveness was increased to between 6.5 and 7.5 mM. Even mutations that resulted in mild impairment of in vitro enzyme activity were associated with a > 50% reduction in ISR. The responsiveness of the beta cell to glucose was increased by 45% in the subjects with mutations after a 42-h intravenous glucose infusion at a rate of 4-6 mg/kg per min. During oscillatory glucose infusion with a period of 144 min, profiles from the subjects with mutations revealed reduced spectral power at 144 min for glucose and ISR compared with controls, indicating decreased ability to entrain the beta cell with exogenous glucose. In conclusion, subjects with mutations in GCK demonstrate decreased responsiveness of the beta cell to glucose manifest by a shift in the glucose ISR dose-response curve to the right and reduced ability to entrain the ultradian oscillations of insulin secretion with exogenous glucose. These results support a key role for the enzyme GCK in determining the in vivo glucose/ISR dose-response relationships and define the alterations in beta-cell responsiveness that occur in subjects with GCK mutations.  相似文献   
110.
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