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91.
Rh血型不合新生儿溶血病检测方法及应用   总被引:3,自引:0,他引:3  
产前检测Rh,D因子及抗人球蛋白(coombs)试验是必要的。测定Rh,D因子及抗D滴度使用木瓜酶方法。通过对11261例孕妇常规检查Rh,D因子,发现D阴性74例。Rh,D阴性妇女占6.5‰。22例Rh,D阴性的孕妇所分娩的新生儿均为Rh,D阳性。其中2例孕妇血清抗D滴度为1∶32,病情严重,宫内输血无效,胎死宫内。初产妇13例,占59%。活产20例,存活率90%。Rh因子及抗人球蛋白试验方法简便、易行,一般医院均可进行。对有流产史、输血史的孕妇检查Rh因子是十分必要的。在有条件的医院,对Rh,D阴性的产妇分娩Rh,D阳性的新生儿之后,产妇应预防性注射抗D免疫球蛋白  相似文献   
92.
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories. Received: 28 May 1996/Accepted: 30 August 1996  相似文献   
93.
以9例ASAⅠ~Ⅱ级、在普鲁卡因-安氟醚静吸复合全麻下择期手术的成人患者为对象,观察了硝酸甘油(NTG)控制性降压(MAP下降30%)对动脉血气的影响。结果:与对照组相比,降压期间PaO2、BE明显下降,PaCO2、Pa-etCO2明显升高。说明NTG控制性降压可给血气带来不良影响。  相似文献   
94.
Abstract: We tried to characterize the porcine platelet nitric oxide (NO) synthase and its L-arginine (L-arg)/NO metabolism. Using RT-PCR we could show a constitutive endothelial NOS (ecNOS) and an inducible NOS (iNOS) similar mRNA in platelets. The NOS protein could be evidenced by an ecNOS specific antibody which also bound in platelets. This finding could be confirmed by Western blot showing an ecNOS in the membrane but not the cytosolic fraction; iNOS protein could not be detected. Using NADPH-diaphorase staining we could show NO synthase in preactivated platelets but not in resting platelets, indicating that the platelet NOS may be activated during platelet activation/aggregation. Porcine L-arg plasma levels (9.31 × 10–5 mol/l ± 10%) could be shown to be in the same range as human plasma levels. Moreover, we could show that the NO precursor L-arg and hydroxy-L-arginine (OHarg) concentration dependently inhibited collagen induced platelet aggregation. Summarizing these results confirm the existence of and further characterize porcine platelet NO synthases.  相似文献   
95.
王真富 《河北医学》2002,8(2):119-121
目的:解释血压在毛细血管前阻力血管中下降最快的原因。方法:利用物理模型简化复杂的心血管系统。结果:全身所有的微、小动脉段“并联”,全身所有的毛细血管段“并联”。结论:微、小动脉段的总流阻最大、使俐血压在微、小动脉中下降最快。  相似文献   
96.
探讨成人原发性肾病综合征(NS)血容量与肾素、醛固酮及心钠素的关系。方法 应用~(113)mInCl标记转铁蛋白稀释法测定血容量,放免法测定血浆激素水平。对水肿期NS28例、正常26例及其中NS缓解期随访18例进行检测。结果 (1)水肿期NS血容量与正常组无差别,血浆肾素活性(PRA)、血管紧张素Ⅱ(ATⅡ)、醛固酮(Ald)、心钠素(ANP)水平均较正常组高,白蛋白、各激素水平与血容量无显著相关;(2)缓解期与水肿期比较,总的血容量无差异,Ald、ANP显著降低,PRA、ATⅡ则无明显差异;(3)Ald与24小时尿排钠(UNaV)显著负相关。结论 Ald和ANP是NS钠排泄的主要调节因子。  相似文献   
97.
In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03~3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3~30μmol/L), indomethacin (0.3~10μmol/L) and PGE_1 (0.01~0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3~3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100~200μmol/L and STA_2 1~3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90~100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment.  相似文献   
98.
对离体不同时间血痕进行肉眼和扫描电镜观察,获得了血痕形态结构变化的初步认识.结果随时间延长,血痕逐渐干燥、龟裂,电镜下纤维蛋白网消失,其超微结构变化观察有助于血痕经过时间的推断.  相似文献   
99.
抗—HCV阳性单采浆供血员HGV感染随访研究   总被引:3,自引:0,他引:3  
为了解单采浆供血员庚型肝炎病毒(HGV)感染及其转归,对102名抗-HCV阳性单采浆供血员冻存血清进行抗-HGV和HGVRNA检测,对抗-HGV和(或)HGVRNA阳性者作3年随访研究。采用EIA法检测抗-HGV,包被抗原来自HGV不同功能区的合成肽。应用RT-PCR法检测HGVRNA,引物选自HGVNS3区。结果表明,抗-HCV阳性单采浆供血员HGVRNA阳性率为19.61%(20/102),抗-HGV阳性率为17.65%(18/102),HGV感染率(抗HGV和/或HGVRNA阳性)为24.51%(25/102),而对照组仅为0.94%(1/106)。提示单采血浆是HGV感染的重要危险因素。HGVRNA和抗-HGV的3年阴转率分别为35.00%(7/20)和11.11%(2/18),说明HGV感染有慢性携带趋势  相似文献   
100.
This study explored the inflammatory mechanism of toxicity of hemoglobin solutions (Hb-S). Human monocytes and mouse activated peritoneal macrophages were incubated with seven different solutions. The first four consisted of non-cross-linked bovine Hb. Of these, Hb-SI was incompletely purified of stromal phospholipids, Hb-SII was contaminated with environmental bacterial endotoxins, Hb-SIII was pure hemoglobin, and Hb-SIV was pure Hb with the addition of superoxide dismutase (SOD), catalase (CAT), and mannitol (M). The other three solutions were made of pure bovine Hb cross-linked with different agents: Hb-SV, reacted with glutaraldehyde; Hb-SVI reacted with bis-3,5-dibromosalicyl fumarate (DBSF); and Hb-SVII reacted with a ring-opened dialdehyde derivative of 5'(pyro)-phosphate of adenosine (ATP) (o-ATP). The reaction of monocytes and macrophages was studied in terms of (a) O2-derived radicals, as determined by the measurement of H2O2 and lipid peroxides; (b) complement factor C3a desArg; (c) 6-keto-prostaglandin F1 alpha (stable metabolite of prostacyclin); and (d) TxB2 (stable metabolite of thromboxane) released into the culture supernatants. The most significant reactions were obtained with the solutions contaminated with stromal phospholipids or bacterial endotoxins. Pure Hb was less reactive. Further reduction in proinflammatory activity was achieved by the addition of oxygen radical-scavengers (SOD, CAT, and M), or by the cross-linking of Hb with DBSF or o-ATP.  相似文献   
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