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21.
We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics.  相似文献   
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胶原-壳聚糖复合材料的制备及生物安全性检测   总被引:4,自引:2,他引:4  
目的:制备胶原-壳聚糖复合细胞载体,并对该载体进行系统的生物学性能检测。方法:实验于2003-07/2006-06在天津市医药科学研究所完成。将胶原溶液和壳聚糖溶液按照一定比例(9∶1)混匀,交联后真空冷冻干燥,制成胶原-壳聚糖复合载体,对该载体进行复合材料性状及理化性能检测。并采用急性全身毒性试验、皮内刺激试验、皮肤致敏试验、溶血试验、细胞毒性试验和致突变试验进行生物学性能检测。结果:①胶原-壳聚糖复合材料具有三维立体多孔结构,适合细胞的三维生长,能为新生组织提供良好的支架。②急性全身毒性试验、皮内刺激试验均阴性,致敏率仅为6.25%,细胞毒性为0级,无诱变能力。结论:从仿生学角度出发,制备出可生物降解的胶原-壳聚糖复合材料,经过系统的生物学评价发现,胶原-壳聚糖复合材料具有良好的生物安全性,对机体无毒,不致突变,对细胞有较强的亲和作用,利于细胞生长和分化。  相似文献   
25.
Most methods used in the risk assessment of heart transplant candidates do not include new biomarkers.

Aims

The aim of the study was to examine the value of NTproBNP and hsCRP and their combined use together with HFSS score in the risk assessment of patients with heart failure enlisted for heart transplantation.

Methods

Data of 658 patients enlisted for heart transplantation in all active transplantation centers were stored in a prospective registry. The composite end point-death or urgent transplantation was recorded during the follow-up.

Results

Death or urgent transplantation was recorded in 161 (24%) of pts. 102 (15%) patients died and 59 (9%) were transplanted urgently. Kaplan-Meier curves for risk of death or urgent transplantation where highly significant when pts were stratified by the quartiles of NT proBNP (P < .000001) or quartiles according to the hsCRP level on admission (P < .002). In the multivariate Cox proportional hazard model, the significance was observed for NTproBNP (P < .01) and HFSS (P < .02), and borderline significance for hsCRP (P = .057). When ROC analyses of the area under the curve (AUC) values were considered, AUC area was for HFSS – 0.645, for NTproBNP – 0.653 and for hsCRP – 0.566. When all those variables were included together in the model, the AUC value rose to 0.6943. Based on those results a weighted risk model with all three parameters was proposed.

Conclusion

HFSS, NTproBNP and hsCRP levels are independent stratification variables of survival or need for urgent heart transplantation. Their predictive value is moderately increased when they are analyzed together.  相似文献   
26.

Objective

To compare oxygen supply options for health facilities in the Gambia and develop a decision-making algorithm for choosing oxygen delivery systems in Africa and the rest of the developing world.

Methods

Oxygen cylinders and concentrators were compared in terms of functionality and cost. Interviews with key informants using locally developed and adapted WHO instruments, operational assessments, cost-modelling and cost measurements were undertaken to determine whether oxygen cylinders or concentrators were the better choice. An algorithm and a software tool to guide the choice of oxygen delivery system were constructed.

Findings

In the Gambia, oxygen concentrators have significant advantages compared to cylinders where power is reliable; in other settings, cylinders are preferable as long as transporting them is feasible. Cylinder costs are greatly influenced by leakage, which is common, whereas concentrator costs are affected by the cost of power far more than by capital costs. Only two of 12 facilities in the Gambia were found suitable for concentrators; at the remaining 10 facilities, cylinders were the better option.

Conclusion

Neither concentrators nor cylinders are well suited to every situation, but a simple options assessment can determine which is better in each setting. Nationally this would result in improved supply and lower costs by comparison with conventional cylinders alone, although ensuring a reliable supply would remain a challenge. The decision algorithm and software tool designed for the Gambia could be applied in other developing countries.  相似文献   
27.
生命科学仪器中光电倍增管偏置电路分压精度的提高   总被引:1,自引:1,他引:0  
目的:分析光电倍增管电压偏置电路对光电倍增管性能的影响,并采取相应措施提高光电倍增管电压偏置电路的精度,以改善光电倍增管的性能。方法:在电阻型光电路倍增管偏置电的基础上,增加双极型晶体管或场效应晶体管构成有源光电倍增管偏置电路;并采用可调恒流技术,以解决温度对电路的影响。结果:在阳极电流为50μA,电阻型光电倍增管偏置电路的线性偏离度已达40%,而用双极性晶体管或场效应晶体管的有源偏置电路的线性偏离度分别为≤7%,≤3%,采用可调恒流技术后,电路的线性偏离度≤1%;如果要求阳极电流为100μA时线性偏离度≤1%时,电阻型光电倍增管偏置电路的功耗为11W,而用双极性晶体管或场效应晶体管的有源偏置电路的总功耗分别在0.18~0.95W,0.12~0.75W。结论:采用场效应晶体管的有源偏置电路显著提高了偏置电压的线性度和稳定性,减少了功耗和体积,加入可调恒流技术后,进一步降低偏置电路的线性偏置度,从而改善了光电倍增管的性能。  相似文献   
28.
The relationship among G3P5A rotavirus strains was analysed by restriction endonuclease assay of the VP4, VP6 and VP7 encoding genes, neutralization assay and phylogenetic analysis. The restriction patterns of the capsid encoding genes were species specific allowing the differentiation among the strains of different origin. The VP7 profiles differentiated human from animal strains more efficiently. The phylogenetic analysis of the VP4 gene demonstrated that HCR3A and K9 are closer related to each other than to other P5A strains. The same occurs to strains Ro1845 and Cat 97. The CU-1 virus appears to be an ancestor of the P5A strains by neutralization and phylogenetic analysis. The results placed the RRV strain definitely in a separate VP4 serotype and genotype from that of P5A strains. Restriction endonuclease assay of the capsid encoding genes seems to be a useful tool to identify the host species of rotavirus strains belonging to the same serotype and/or genotype.  相似文献   
29.
一种用于筛选降血糖及降血脂药物的动物模型   总被引:6,自引:0,他引:6  
一种用于筛选降血糖及降血脂药物的动物模型刘京,申竹芳,刘海帆,叶菲,谢明智(中国医学科学院药物研究所,中国协和医科大学北京100050)糖尿病为常见病和多发病,同时伴有多方面的并发症,脂质代谢紊乱即其中之一。这就要求治疗糖尿病时,除控制病人的血糖外,...  相似文献   
30.
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