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Paula Tanabe PhD RN Demetrious N. Kyriacou MD PhD Franklyn Garland MT 《Academic emergency medicine》2003,10(8):897-900
OBJECTIVES: To evaluate simultaneously several possible risk factors for blood bank specimen hemolysis. METHODS: This was a prospective cohort study of emergency department and labor and delivery patients to estimate the effect of various factors on the risk of blood bank specimen hemolysis. Study variables included patient demographics, type and gauge of needle or catheter, anatomic location of venipuncture, and patient care area. Hemolysis was determined by blood bank laboratory technicians. Cox proportional hazards multivariate regression modeling was performed to estimate the adjusted relative risks for hemolysis. RESULTS: Of the 605 subjects with complete data, 194 (32.1%) subjects had blood specimens drawn directly with a steel needle, and 411 (69.1%) had specimens drawn through a Vialon (BD Medical Systems, Inc., Sandy, UT) intravenous (IV) angiocatheter. The overall risk of hemolysis for all was 7%, 10% for Vialon IV angiocatheters and 1.5% for steel needles. In the multivariate analysis, the factors most closely associated with hemolysis were the use of Vialon IV catheters and sampling from an anatomic site other than the antecubital area. CONCLUSIONS: Blood bank specimens drawn from Vialon IV catheters (particularly smaller gauge catheters) and from veins outside the antecubital area are at significantly increased risk to hemolyze. 相似文献
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目的:流行病学调查结果显示,地方性氟中毒与甲状腺肿的流行有很大的重叠性。探讨氟化钠对原代培养猪甲状腺细胞及甲状腺过氧化物酶活性的影响。方法:实验于2006-10/2007-05在辽宁医学院科学实验室中心完成。①实验方法:在猪死亡1h内取其甲状腺组织,去除甲状腺组织包膜及外层活性差的组织,选取中央活性高的部位,剪成1mm3组织块,用胰蛋白酶、胶原酶Ⅳ消化分离,得到含猪甲状腺细胞的消化液,沉淀悬于含体积分数为0.15的胎牛血清、1U/L牛促甲状腺素、80万U/L庆大霉素的F12培养基中,过滤,调整细胞浓度至5×105L-1,接种培养,每3d更换培养液。常规培养48h的猪甲状腺细胞接种于96孔培养板,按氟化钠终浓度不同分为0,40,80,160mg/L组。②实验评估:染毒48h后,采用噻唑蓝法测定细胞存活量,采用改良愈创木酚法测定甲状腺过氧化物酶活性。结果:①氟化钠对原代培养猪甲状腺细胞存活量的影响:与0mg/L氟化钠比较,40mg/L氟化钠染毒后猪甲状腺细胞的存活量基本相似;80,160mg/L氟化钠染毒后猪甲状腺细胞的存活量均明显下降(P<0.01)。②氟化钠对甲状腺过氧化物酶活性的影响:与0mg/L氟化钠比较,40,80,160mg/L氟化钠染毒后的甲状腺过氧化物酶活性均明显下降(P<0.01),呈剂量-效应关系。结论:氟化钠对原代培养的猪甲状腺细胞及甲状腺过氧化物酶活性均具有抑制作用。 相似文献
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Design and implementation of a combined influenza immunization and tuberculosis screening campaign with simulation modelling 下载免费PDF全文
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ObjectiveExtracts of Ganoderma species have been widely used as herbal medicines in the treatment of several infections. This study was carried out to ascertain the haematological properties of aqueous Ganoderma applanatum (G. applanatum).MethodsSixty albino rats grouped into six equal groups (10 each) of A to F consisting of tests and controls. Laboratory albino rats in groups A, B and C were infected with Trypanosoma brucei brucei (T. brucei brucei) while groups A and B (test) were treated with aqueous G. applanatum extract; other groups served as control. Microscopy and haematological profiles from the albino rats were monitored on daily basis for blood parasites, packed cell volume (PCV), haemoglobin concentration (HC), total red blood cell count (RBC), mean cell haemoglobin (MCH), mean cell volume (MCV), mean cell haemoglobin concentration (MCHC), and total white blood cell count (WBC).ResultsAlbino rats in groups A, B and C infected with T. brucei brucei and treated with various concentrations of aqueous G. applanatum showed a progressive reduction in PCV, HC, RBC, MCH and MCHC compared to the controls (P<0.05). All the infected rats died by day 14 of the experiment from parasitaemia.ConclusionsG. applanatum lacks ability to boost haematological profiles of anaemic laboratory rats and also of no use in the treatment of African trypanosomiasis. Higher doses of the fungal extract may be required to test on laboratory rats with less lethal biological stimulants of anaemia before proving or otherwise its true haematological properties. 相似文献
78.
Batard P; Sansilvestri P; Scheinecker C; Knapp W; Debili N; Vainchenker W; Buhring HJ; Monier MN; Kukk E; Partanen J; Matikainen MT; Alitalo R; Hatzfeld J; Alitalo K 《Blood》1996,87(6):2212-2220
Growth factor receptors in human hematopoietic progenitor cells have become the focus of intense interest, because they may provide tools for the monitoring, enrichment, and expansion of stem cells. We have shown earlier that the Tie receptor tyrosine kinase is expressed in erythroid and megakaryoblastic human leukemia cell lines, in the blood islands of the yolk sac, and in endothelial cells starting from day 8.0 of mouse development. Here, the expression of Tie was studied in human hematopoietic cells of various sources. Peripheral blood mononuclear cells were Tie-. However, a large fraction of CD34+ cells from umbilical cord blood (UCB) and bone marrow (BM) expressed tie protein and mRNA. On average, 64% of the fluorescence-activated cell sorting- gated UCB CD34+ cells including CD38- cells and a fraction of cells expressing low levels of c-Kit were Tie+. Also, 30% to 60% of BM CD34+ cells were Tie+, including most of the BM CD34+CD38-, CD34+Thy-1+, and CD34+HLA-DR- cells. Under culture conditions allowing myeloid, erythroid, and/or megakaryocytic differentiation, purified UCB CD34+ cells lost Tie mRNA and protein expression concomitantly with that of CD34; however, a significant fraction of cells expressed Tie during megakaryocytic differentiation. These data suggest that, in humans, the Tie receptor and presumably its ligand may function at an early stage of hematopoietic cell differentiation. 相似文献
79.
Society stress and peptic ulcer perforation 总被引:1,自引:0,他引:1
SHIU-KUM LAM WAI-MO HUI LING-PO SHIU MATTHEW MT NG 《Journal of gastroenterology and hepatology》1995,10(5):570-576
To examine the relationship between society stress and peptic ulcer perforation, time-trend analysis was performed on the annual incidence of perforated peptic ulcer per 100 000 population in Hong Kong during the years 1962–85, when Hong Kong, as a developing city, went through significant socio-economic and political changes, and the trend was correlated with specially designed and validated society stress scores estimated annually during the same period. The society stress scores were derived independently by two expert panels blinded to the purpose of the study, one selecting and categorizing negative news events for Hong Kong during this period, and the other weighing the categories and scoring the impact of the news on Hong Kong. The incidence of perforation increased significantly during the years and manifested three distinct peaks, which coincided with the worst economic recession in Hong Kong, the influx of mainlander Chinese and Vietnamese boat people, and the Sino-British negotiation on the sovereignty of Hong Kong after 1997. Both linear and autoregression analysis, the latter taking into consideration point fluctuations in rates, showed that perforation rates correlated significantly with the society stress scores (r= 0.57, P < 0.002). The peak effects and the significant correlations indicate that an association exists between society stress and peptic ulcer perforation, and suggest that chronic society stress plays an important role in the aetiology of this condition, although the relatively low r value also suggests the presence of other aetiological factors. 相似文献
80.
Thrombospondin interaction with plasminogen. Evidence for binding to a specific region of the kringle structure of plasminogen 总被引:1,自引:0,他引:1
Platelet thrombospondin interacts with plasminogen in a specific and saturable manner. Thrombospondin was found to specifically bind to plasminogen and the nonenzyme chain of plasmin. Preincubation of 125I- labeled thrombospondin with 30 mmol/L lysine was without effect in the binding of thrombospondin to immobilized plasminogen; preincubation of 125I-labeled plasminogen with 30 mmol/L lysine, on the other hand, significantly reduced the binding of plasminogen to immobilized thrombospondin, suggesting that the interaction of thrombospondin with plasminogen is not the direct result of the lysine binding sites of plasminogen. Arginine and benzamidine, ligands known to specifically bind to the kringle 5 domain of plasminogen, blocked the binding of thrombospondin to plasminogen. Limited elastase proteolysis of plasminogen and plasmin resulted in the generation of two distinct thrombospondin binding domains, one of which was retained on lysine- agarose. The isolation and amino-terminal analysis of these domains following elastase proteolysis of plasminogen identified them, respectively, as a domain containing kringle structures 4 and 5 and plasmin and the other domain consisting of kringle 5-plasmin. A 16- residue synthetic peptide, which represents the amino acids linking kringle 4 to kringle 5 (residues 435-450 of native plasminogen), was without effect in either binding to thrombospondin or blocking the binding of thrombospondin to plasminogen. Plasminogen, therefore, possesses a single thrombospondin interactive site that is independent of, but influenced by, the lysine binding site containing kringle structures and most likely is located within the kringle 5 domain. 相似文献