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991.
Intussusception associated with Yersinia pseudotuberculosis infection was developed in three boys; two of them had a history of drinking untreated water. All intussusceptions were localized at the ileocolic region, and all patients completely recovered with GastrografinR enema and supportive treatment without complication and operation. 相似文献
992.
BACKGROUND : An increase from 8 to 24 hours in the time that units of whole blood can be held at room temperature after phlebotomy would give blood centers more flexibility in component manufacturing and might allow receipt of many infectious disease test results prior to component preparation. However, the potential for bacterial growth during prolonged holding periods requires further study. STUDY DESIGN AND METHODS : In the Phase I study, 2-unit pools of ABO-identical whole blood were deliberately inoculated on Day 0 with Staphylococcus aureus or Pseudomonas fluorescens. They were then divided in half and stored at 20 to 24 degrees C. Red cells (RBCs) with additive solution, platelet concentrates (PCs), and frozen plasma were prepared after 8 and 24 hours. Bacteria levels in PCs and RBCs were monitored on Day 1; bacteria levels were measured in plasma after thawing. In the Phase II study, the same basic design as in Phase I was used, except that 10 bacterial species were studied, lower inocula were used, and RBCs prepared after a 24-hour room-temperature whole-blood hold were white cell-reduced by filtration. Bacterial growth was monitored during 42- day storage of RBCs (1 – 6 degrees C) and 5-day storage of PCs (20 – 24 degrees C) and after thawing of frozen plasma. RESULTS : For Phase I, significantly higher bacteria levels were observed in RBCs prepared after a prolonged hold (p < 0.05); higher levels were not observed in PCs and thawed plasma units. In Phase II, prior to white cell reduction by filtration, 8 of 10 organisms had significantly higher levels in RBCs prepared after a 24-hour hold than in RBCs prepared after an 8- hour hold, when both were examined on Day 1 (p < 0.05). For seven of eight organisms examined on Days 1, 21, and 42, filtration (white cell reduction) reduced the bacteria in RBCs prepared from 24-hour whole blood units to those levels found in unfiltered RBCs prepared from whole blood units held at 8 hours. A prolongation of the holding time from 8 to 24 hours resulted in significantly lower bacteria levels (p < 0.05) in PCs early in storage (Days 1, 1 – 2, or 1 – 3) for seven organisms, with no significant difference for two organisms, and a small but significant increase for one organism (Day 3, p < 0.05). There was no difference in bacteria or endotoxin levels in thawed units of plasma prepared from whole blood after 8- or 24-hour holding times. CONCLUSION : The levels of bacteria present in components after deliberately inoculated whole blood units are held for 8 and 24 hours depended on the organisms tested, the whole-blood holding period, and the blood component assayed; for RBCs, they also depended on whether WBC reduction by filtration was performed. 相似文献
993.
994.
目的:目前国外已有少量报道证实中药大黄素具有极强的免疫抑制效应。实验拟进一步验证大黄素对同种异体大鼠肝移植术后早期急性排斥反应的干预效果。方法:实验于2004-01/2005-02在西安交通大学第一附属医院肝胆外科实验室完成。制备SD→Wistar大鼠全血供肝移植模型(n=80),按随机数字表法分为4组,每组20只。模型对照组、大黄素组、环孢素A组及环孢素A 大黄素组分别腹腔注射给予9g/L生理盐水、1.5mg/(kg·d)大黄素、3mg/(kg·d)环孢素A及3mg/(kg·d)环孢素 1.5mg/(kg·d)大黄素。术后观察大鼠一般情况,并于第7天各组分别处死10只大鼠,取肝脏标本及血清,观察移植肝组织排斥反应强度、Fractalkine(Fkn)阳性表达情况及大鼠血清中白蛋白含量及谷丙转氨酶活性,余受体继续应用药物干预直至死亡,记录其生存时间。结果:各组受体手术成功数量分别为模型对照组17只、大黄素组18只、环孢素A组18只、环孢素A 大黄素组18只。①与模型对照组相比,各用药组大鼠术后存活时间明显延长(P<0.05),以环孢素A 大黄素组存活时间最长。②与模型对照组相比,各用药组大鼠术后第7天移植肝排斥反应强度明显降低(P<0.05),血清中白蛋白含量明显升高,而谷丙转氨酶活性明显降低(P均<0.05),肝组织中Fkn表达阳性率明显降低(P<0.05),以环孢素A 大黄素组表现最为显著。结论:大黄素具有抑制同种异体大鼠肝移植急性排斥反应发生、发展的作用,与环孢素A联用具有协同作用。 相似文献
995.
BACKGROUND: The ability to store pools of platelet concentrates (PCs) for extended periods would provide logistical flexibility. However, reports of severe adverse reactions due to the transfusion of contaminated PCs led to an examination of whether the total bacteria levels after storage of pools containing a deliberately inoculated platelet unit would be significantly different than the levels in paired unpooled concentrates. STUDY DESIGN AND METHODS: A single PC was deliberately inoculated on Day 0 with one of three bacterial species (0.1–8.0 colony-forming units/mL). On Day 1, the deliberately inoculated PC was divided into three equal parts and either 1) pooled with 5 half-volume, ABO- and Rh-identical PCs; 2) similarly pooled and white cell reduced; or 3) kept as a control. Sterile connections were used during pooling; modified storage containers were used to ensure the correct surface-to-volume ratio of the single unit. RESULTS: Between Day 2 and Day 5 of storage, in 26 of 36 paired samples, nonfiltered pools containing Escherichia coli had greater total numbers of bacteria than did the paired single PCs. Day 2 pools had total bacteria levels approximately five times higher (colony-forming units/mL × container volume) than those in single units (p < 0.05). There was rapid growth of Staphylococcus aureus by Day 2 in pooled and unpooled PCs; by Day 3, total bacteria levels were approximately five times higher in pools than in single units (p < 0.05). Between Days 3 and 5 of storage, in 23 of 27 paired samples, nonfiltered pools containing S. aureus had greater total bacteria levels than the single PCs. By Day 5, 15 of 16 non-white-cell reduced pools had total levels of Staphylococcus epidermidis bacteria approximately five times those in the paired single PCs. Greater total bacteria levels in pooled units than in single units generally occurred when bacteria in pools reached the stationary phase of growth (when bacteria concentration became constant), and they were well correlated with the sixfold volume of pooled units. White cell reduction did not substantially affect the time required to attain stationary phase. CONCLUSION: The potential during storage for greater total bacteria levels in pools than in single PCs is a consequence of the greater volume of the pool. 相似文献
996.
目的:本文就分离克隆胰腺干细胞,并将其定向诱导分化为功能性胰岛移植治疗糖尿病的研究作一综述。资料来源:应用计算机检索CBM和PubMed数据库1978-01/2006-12胰腺干细胞或胰岛干细胞移植治疗糖尿病的文章,检索词为"islet stem cell,pancreatic stem cell,diabetes mellitus,胰腺干细胞,胰岛干细胞,糖尿病"。资料选择:选择胰腺干细胞或胰岛干细胞移植治疗糖尿病的文章,排除重复研究。资料提炼:检索到CBM数据库中胰腺干细胞移植治疗糖尿病文章19篇,胰岛干细胞移植治疗糖尿病文章20篇;PubMed数据库中胰腺干细胞移植治疗糖尿病文章305篇。共纳入41篇。资料综合:糖尿病的治疗方法主要包括药物治疗、胰岛素注射、胰腺器官移植和胰岛细胞移植。胰腺器官移植和胰岛移植是治疗糖尿病的有效方法。由于缺乏完全合适的供体,胰腺器官移植的临床应用受到限制。与胰腺器官移植相比,胰岛细胞移植无需麻醉和剖腹,减小了对移植受体的损伤,降低了风险性。结论:体外分离、克隆人类胰腺干细胞,并定向诱导其分化为功能性胰岛移植治疗糖尿病,是解决胰岛供体短缺的有效途径,但是还没有人胰腺干细胞体外诱导胰岛移植治疗人类糖尿病的报道。 相似文献
997.
Hutchinson SJ; Brettle RP; Gore SM 《QJM : monthly journal of the Association of Physicians》1997,90(11):685-692
We tested the validity of a previously-published AIDS staging system by
examining AIDS-defining diseases (ADDs) and CD4 counts as prognostic
factors for survival of the 248 AIDS patients in the Edinburgh City
Hospital Cohort, of whom 56% were injecting drug-users (IDUs). Cox
regression was used to model the proportionality of risk of death as the
CD4 count declined and more ADDs were experienced, and dependence upon
post-AIDS treatment. Using the system of Mocroft et al. (Lancet 1995;
346:12-17) to grade severity, our data were well enough modelled, but we
suggest: (i) regrading of HIV dementia (RR 3.9, 95% CI 2.5-6.0), mainly
attributed to the drug users, to a very severe ADD; (ii) reduction in risk
from zidovudine (RR 0.7, 95% CI 0.5-1.0) during AIDS follow-up for patients
starting treatment at or after AIDS diagnosis; (iii) improved management of
first mild ADDs (from 1987-89 to 1994-95: 40% reduction in IDUs appearing
with mild index diseases, and an approximate three-fold reduction in risk
associated with a mild ADD). This study supports previous findings on the
significance of ADDs and lowest CD4 count in predicting the lifetime of
AIDS patients.
相似文献
998.
Severe bloodstream infections: a population-based assessment 总被引:4,自引:0,他引:4
Laupland KB Gregson DB Zygun DA Doig CJ Mortis G Church DL 《Critical care medicine》2004,32(4):992-997
OBJECTIVE: Although bloodstream infection commonly results in critical illness, population-based studies of the epidemiology of severe bloodstream infection are lacking. We sought to define the incidence and microbiology of severe bloodstream infection (bloodstream infection associated with intensive care unit admission within 48 hrs) and assess risk factors for acquisition and death. DESIGN: Population-based surveillance cohort. SETTING: Multidisciplinary and cardiovascular surgical intensive care units. PATIENTS: All adults with severe bloodstream infection in the Calgary Health Region (population approximately 1 million) during 2000-2002. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Three hundred forty patients had 342 episodes of severe bloodstream infection (15.7 per 100,000 population/year). Several demographic and chronic conditions were significant risk factors for acquiring severe bloodstream infection (relative risk, 95% confidence interval) including age > or =65 yrs (7.0, 5.6-8.7), male gender (1.3, 1.1-1.6), urban residence (2.4, 1.2-5.6), hemodialysis (208.7, 142.9-296.3), diabetes mellitus (5.9, 4.4-7.8), alcoholism (5.6, 3.8-8.0), cancer (7.5, 5.3-10.3), and lung disease (3.8, 2.6-5.4). The most common etiologies were Staphylococcus aureus, Escherichia coli, and Streptococcus pneumoniae (3.0, 3.0, and 1.9 per 100,000/year, respectively). The case-fatality rate was 142 of 340 (42%) for an annual mortality rate of 6.5 per 100,000. Increased Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.1 per point; 95% confidence interval, 1.1-1.2) and presence of a comorbidity (odds ratio, 2.5; 95% confidence interval, 1.4-4.3) were significant independent predictors of death. CONCLUSIONS: Bloodstream infections are commonly severe enough to require management in an intensive care unit and are associated with a high mortality rate. Identification of risk factors for severe bloodstream infection may allow targeting of preventive efforts to individuals at greatest potential benefit. 相似文献
999.
Recruiting blood donors into a local bone marrow donor registry 总被引:1,自引:0,他引:1
To date, most persons joining bone marrow donor registries have been recruited from platelet-pheresis panels. The potential of recruiting regular blood donors into bone marrow donor registry (BMDR) was explored. It was found that, with minimal effort, 6.2 percent of the age-eligible blood donors were recruited. A distinguishing feature of those who joined the BMDR was a history of frequent blood donations. Although local media attention had a major impact on recruitment, even those joining as a result of the publicity usually were regular blood donors. This program has the potential to recruit nearly 8000 volunteers from 120,000 regular blood donors over an 18-month period. 相似文献
1000.
SJ Skingle RGN DJ Moore MB FRCR AJ Crisp MD FRCP 《International journal of clinical practice》1997,51(6):364-367
To determine whether cyclical etidronate modifies bone density in patients on chronic glucocorticosteroid therapy, annual bone density measurements were performed on 55 patients receiving glucocorticosteroids who were randomised to either continuous calcium supplementation or cyclical etidronate plus calcium supplementation in this secondary prevention study. Median L1-L4 lumbar spine bone density decreased by 0.7% in the calcium treated group after one year but increased by 3.1% in the group treated by calcium and etidronate (p=0.00116). Median L1-L4 bone density decreased by 2.8% from baseline after two years in the calcium treated group but increased by 4.7% from baseline In the group treated by calcium and etidronate (p=0.04). There were no significant effects of treatment on femoral neck density. Cyclical etidronate and calcium increased lumbar spine bone density in patients established on prednisolone treatment over a two-year period but had no effect on femoral density. 相似文献