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71.
Many people believe that euthanasia and assisted suicide are condoned carte blanche in the Netherlands. Not true. Both are formally forbidden by criminal law and can be administered only when certain procedures and criteria have been followed. Below, a look at the policies and practices regarding euthanasia and assisted suicide in The Netherlands and the role of nurses in this area. 相似文献
72.
To determine the cause of a positive direct antiglobulin test (DAT), blood banks routinely perform serologic tests on eluates prepared from DAT-positive red cells. Negative eluates traditionally have been suspected to be associated with drug reactions. This report confirms that the most frequent cause of a positive DAT and a nonreactive eluate is hypergammaglobulinemia. The results of 74 patient samples with positive DATs were analyzed retrospectively. Eluates prepared from the red cells of 54 patients (72.9%) reacted; eluates from 20 patients (27.1%) did not react. This latter group had identical serologic and clinical findings, suggesting that they made up a homogeneous group. In particular, the patients had a positive DAT, a negative indirect antiglobulin test, and a negative eluate; an increased serum concentration of IgG; and no evidence of hemolysis. In a subsequent study, DATs were performed prospectively on red cells from 44 consecutive patients with elevated serum IgG levels. The serum IgG concentration was highest in the three patients whose red cells had a positive DAT. The DAT also became positive in two patients treated with high-dose intravenous gammaglobulin (IV IgG). These studies indicate that a negative eluate from red cells with a positive DAT, a common serologic finding, is often caused by hypergammaglobulinemia. The authors postulate that IgG binds nonspecifically to the red cells because of the hypergammaglobulinemia. 相似文献
73.
许建刚 《中国组织工程研究与临床康复》2007,11(47):9543-9546
目的:终末期肝硬化患者肝病晚期常合并肝肺综合征,伴随低氧血症出现,在肝移植期间进行针对性的通气治疗和管理,对于降低肝移植期的肺部并发症,甚至降低死亡率具有重要的临床意义。文章综合分析低潮气量和低呼期末正压通气对肝移植期间呼吸治疗的作用及其愈后。资料来源:应用计算机检索1970-01/2007-07MEDLINE及万方数据库有关肝移植期间呼吸治疗方面的文献。中文检索词包括"肝移植,肝肺综合征,潮气量,正压呼吸";英文检索词有"liver transplantation,hepato-pulmonary zsyndrome,Tidal ventilation,end-expiratory positive pressure mechanical ventilation"。包括临床研究(不限观察对象的年龄、性别、种族)和基础研究,不限体内或体外研究。资料选择:共收集到1310篇文献,阅读全部文章的文题和大部分文章的摘要,选择肝肺综合征病理改变和通气治疗方面的文献。排除重复性研究和Meta分析类文章。资料提炼:共得到符合纳入条件的文献159篇,排除1141篇。选择其中27篇英文文献及4篇中文文献进行分析。资料综合:①肝肺综合征发病机制错综复杂,术中血流动力学变化及新肝期内毒素、炎性介质、内环境改变等均易发生顽固性低氧血症,甚至出现通透性肺水肿,导致呼吸和心功能衰竭。这些变化是多因素共同作用的结果,在众多发病机制中,肺不张、门肺分流、通气减少或灌流增加均可使通气/灌流比值降低,是导致低氧血症的重要原因。②目前关于肝肺综合征主要是药物处理文献较多,但呼吸治疗报道尚未见到。③根据临床表现术前动脉血氧分压<60mmHg(1mmHg=0.133kPa),动脉二氧化碳分压在正常范围,以及新肝期供肝炎性介质释放,类似于急性呼吸窘迫综合征,因此临床处理均采用呼吸治疗,小潮气量和呼气末正压治疗效果及预后较好。结论:肝肺综合征患者肝移值围手术期应用小潮气量和呼气末正压机械治疗,可降低术后肺部并发症和重症监护时间。 相似文献
74.
目的:对长期以来关于骨纤维结构不良大量相关研究及文献进行回顾,综述骨纤维结构不良的诊断和治疗的最新进展。资料来源:通过计算机互联网检索OVID数据库1966-01/2006-10关于骨纤维结构不良的文献,检索词:Osteofibrous dysplasia,限定语言种类为English。同时检索1994-01/2006-10中国全文期刊数据库有关骨纤维结构不良的文献,检索词为:骨纤维结构不良,限定语言种类为中文。资料选择:选择与骨纤维结构不良相关的观察对比研究、经验总结、个案报道、最新研究进展等文献,力求资料全面,排除重复研究。资料提炼:共收集相关国内外文献41篇,排除重复性研究11篇,采用30篇,包括关于骨纤维结构不良定义、发病机制、病理、诊断及治疗等。资料综合:①骨纤维结构不良是一种起源于纤维组织的良性骨肿瘤。发病率低、误诊率高。目前具体发病机制不明,现认为与常染色体显性遗传有关。②骨纤维结构不良好发于胫骨,症状为局部肿块。特征性影像学表现为胫骨中段前侧皮质膨胀性密度减低。确诊方法为病理检查。重点与骨纤维异常增殖症、造釉细胞瘤相鉴别,现有大量研究证明该病与造釉细胞瘤有联系。③治疗上过去认为10岁以前应保守治疗,10岁后选择手术治疗,目前倾向于早期骨膜外切除手术治疗。结论:骨纤维结构不良发病率低,对该病认识较少,误诊率较高,重点需与骨纤维异常增殖症、造釉细胞瘤相鉴别,应提高对该病的认识与重视程度,对可疑者行病理检查,确诊者行骨膜外切除,切除范围较大的病例行重建手术。 相似文献
75.
Little DM; Farrell JG; Cunningham PM; Hickey DP 《QJM : monthly journal of the Association of Physicians》1997,90(10):641-642
Systemic donor infection is regarded as being an absolute contraindication
to cadaveric organ donation for transplantation. This is largely due to
fear of transmitting pathogenic organisms to the immunosuppressed
recipient. However, due to the current shortage of organs available for
transplantation, clinicians are faced with the option of using organs from
'non-ideal' donors, such as those patients with documented evidence of
infection. We report the successful outcome of six orthotopic liver
transplants, 11 renal transplants, one combined heart lung transplant and
one simultaneous kidney and pancreas transplant with organs from eight
donors in whom bacterial meningitis (n = 7) and acute bacterial
epiglottitis (n = 1) were the antecedent causes of death.
相似文献
76.
FcR gamma-chain is essential for both surface expression and function of human Fc gamma RI (CD64) in vivo 总被引:5,自引:0,他引:5
van Vugt MJ; Heijnen AF; Capel PJ; Park SY; Ra C; Saito T; Verbeek JS; van de Winkel JG 《Blood》1996,87(9):3593-3599
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo. 相似文献
77.
Background
Pressure ulcers are a common, painful and costly condition. Results of a 1991 study into the knowledge among Dutch hospital nurses on the usefulness of measures to prevent pressure ulcers showed moderate knowledge. Results were confirmed by subsequent studies. In recent years, Dutch guidelines have been updated and the attention given to pressure ulcer care has been increased. This was expected to improve pressure ulcer care and to increase nurses' knowledge. The aims of the current study were to investigate (1) how much nurses employed in Dutch hospitals know about the usefulness of 28 preventive measures considered in the most recent national pressure ulcer guideline; (2) whether differences in knowledge exist between nurses working in hospitals that audit pressure ulcers and those employed in hospitals that do not; and (3) to study whether knowledge among Dutch hospital nurses regarding the usefulness of preventive measures had changed between 1991 and 2003. 相似文献78.
79.
P Malherbe E Borroni L Gobbi H Knust M Nettekoven E Pinard O Roche M Rogers-Evans JG Wettstein J-L Moreau 《British journal of pharmacology》2009,156(8):1326-1341
Background and purpose:
The OX2 receptor is a G-protein-coupled receptor that is abundantly found in the tuberomammillary nucleus, an important site for the regulation of the sleep-wake state. Herein, we describe the in vitro and in vivo properties of a selective OX2 receptor antagonist, N-ethyl-2-[(6-methoxy-pyridin-3-yl)-(toluene-2-sulphonyl)-amino]-N-pyridin-3-ylmethyl-acetamide (EMPA).Experimental approach:
The affinity of [3H]EMPA was assessed in membranes from HEK293-hOX2-cells using saturation and binding kinetics. The antagonist properties of EMPA were determined by Schild analysis using the orexin-A-or orexin-B-induced accumulation of [3H]inositol phosphates (IP). Quantitative autoradiography was used to determine the distribution and abundance of OX2 receptors in rat brain. The in vivo activity of EMPA was assessed by reversal of [Ala11,D-Leu15]orexin-B-induced hyperlocomotion during the resting phase in mice and the reduction of spontaneous locomotor activity (LMA) during the active phase in rats.Key results:
[3H]EMPA bound to human and rat OX2-HEK293 membranes with KD values of 1.1 and 1.4 nmol·L−1 respectively. EMPA competitively antagonized orexin-A-and orexin-B-evoked accumulation of [3H]IP at hOX2 receptors with pA2 values of 8.6 and 8.8 respectively. Autoradiography of rat brain confirmed the selectivity of [3H]EMPA for OX2 receptors. EMPA significantly reversed [Ala11,D-Leu15]orexin-B-induced hyperlocomotion dose-dependently during the resting phase in mice. EMPA, injected i.p. in rats during the active phase, reduced LMA dose-dependently. EMPA did not impair performance of rats in the rotarod procedure.Conclusions and implications:
EMPA is a high-affinity, reversible and selective OX2 receptor antagonist, active in vivo, which should prove useful for analysis of OX2 receptor function. 相似文献80.