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21.
1 临床资料 本组62例中,男38例,女24例;年龄最大67岁,最小21岁,平均36岁;病程最长8 a,最短2个月,平均15个月.全部病例均有眩晕症状,常在颈部旋转或屈伸时出现或加重,伴颈枕部不适或疼痛,颈肌僵硬.伴耳鸣32例,伴恶心或呕吐23例,伴上肢麻木感15例.  相似文献   
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目的 探讨星状神经节阻滞 (stellate ganglion block,SGB)加服药物对偏头痛的治疗作用。方法  2 4 0例偏头痛患者按就诊顺序分为观察组与对照组 ,观察组接受 SGB治疗的同时 ,口服尼莫地平等药物。结果 观察组有效率达89.2 % ,高于对照组 (P<0 .0 5 ) ,其中治疗后完全无痛的病例 5 1.7% ,高于对照组 (P<0 .0 1) ,观察发现病程对于 SGB治疗偏头痛疗效影响较大 (P<0 .0 5 )。结论  SGB加服药物治疗偏头痛具有操作简单 ,起效快 ,疗效确切 ,副作用少等优点 ,值得临床推广应用。  相似文献   
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本文介绍了1种由BCM-80单板机到AppleⅡ微机的图象数据传输方法。这种方法以盒式磁带作为传输工具,并采用AppleⅡ的磁带记录格式将由BCM-80所采集的同位素扫描图象数据传送到AppleⅡ微机之中,进行分析处理,然后输出1幅静止的易于识别和诊断的图象。此种方法不需要增加任何硬件,具有简单、可靠、传输速度快等优点。  相似文献   
24.
Serum-resistant lipopolyplexes for gene delivery to liver tumour cells.   总被引:1,自引:0,他引:1  
In this study, an efficient non-viral gene transfer system has been developed by employing polyethylenimine (PEI 800, 25 and 22kDa) and DOTAP and cholesterol (Chol) as lipids (lipopolyplex), at three different lipid/DNA molar ratios (2/1, 5/1 and 17/1) by using five different protocols of formulation. Condensation assays revealed that PEI of 800, 25 and 22kDa were very effective in condensing plasmid DNA, leading to a complete condensation at N/P ratios above 4. Addition of DOTAP/Chol liposomes did not further condense DNA. Increasing the molar ratio lipid/DNA in the complex resulted in higher positive values of the zeta-potential, while the particle size increased in some protocols, but not in others. High molecular weight PEI (800kDa) used in the formulation of lipopolyplexes lead to a bigger particle size, compared to that obtained with smaller PEI species, whether branched (25kDa) or linear (22kDa). These vectors were also highly effective in protecting DNA from attack by DNAse I. Transfection activity was maximal by using protocols 3 and 4 and a lipid/DNA molar ratio of 17/1. These complexes showed high efficiency in gene delivery of DNA to liver cancer cells, even in the presence of high concentration of serum (60% FBS). On the other hand, complexes formed with linear PEI (22kDa) were more effective than lipopolyplexes containing branched PEI (800 or 25kDa). The complexes resulted to be much more efficient than conventional lipoplexes (cationic lipid and DNA) and polyplexes (cationic polymer and DNA). The same behaviour was observed for complexes prepared in the presence of the therapeutic gene pCMVIL-12. Toxicity assays revealed a viability higher than 80% in all cases, independently of the protocol, molar ratio (lipid/DNA), molecular weight and type of PEI.  相似文献   
25.
The choroid plexuses (CPs) form a protective interface between the blood and the ventricular cerebrospinal fluid (CSF). To probe into the pathways by which CPs provide brain protection, we sought to evaluate the efficiency of glutathione conjugation in this barrier as a mechanism to prevent the entry of blood-borne electrophilic, potentially toxic compounds into the CSF, and we investigated the fate of the resulting metabolites. Rat CPs, as well as human CPs from both fetal and adult brains, displayed high glutathione-S-transferase activities. Using an in vitro model of the blood-CSF barrier consisting of choroidal epithelial cells cultured in a two-chambered device, we showed that glutathione conjugation can efficiently prevent the entry of 1-chloro-2,4-dinitrobenzene (CDNB) into the CSF, a model for electrophilic compounds. The duration of this enzymatic protection was set by the concentration of CDNB to which the epithelium was exposed, and this barrier effect was impaired only on severe epithelial intracellular glutathione and cysteine depletion. The conjugate was excreted from the choroidal cells in a polarized manner, mostly at the blood-facing membrane, via a high-capacity transport process, which is not a rate-limiting step in this detoxification pathway, and which may involve transporters of the ATP-binding cassette c(Abcc) and/or solute carrier 21 (Slc21) families. Supplying the choroidal epithelium at the blood-facing membrane with a therapeutically relevant concentration of N-acetylcysteine sustained this neuroprotective effect. Thus, glutathione conjugation at the CP epithelium coupled with the basolateral efflux of the resulting metabolites form an efficient blood-CSF enzymatic barrier, which can be enhanced by pharmacologically increasing glutathione synthesis within the epithelial cells.  相似文献   
26.
犬海水中火器伤后早期血流动力学变化   总被引:3,自引:0,他引:3  
OBJECTIVE: To investigate the hemodynamic changes in the early stages of gunshot wound of dogs in seawater for exploring early treatment protocol. METHOD: Fourteen conventional Beagles models undergoing gunshot wound in seawater were used along with another 2 dogs receiving the wound on land to serve as control. After the dogs were rescued from the seawater, the respiration (R), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), central venous pressure (CVP), pulmonary arterial wedge pressure (PAWP), and cardiac output (CO) were measured continuously in the early stages of the wound (53.62+/-12.19 min following injury), followed by statistical analysis of the results. RESULTS: Compared with the control group, the hemodynamic disturbance of the dogs receiving the wound in seawater was relatively severe during the first 15 min of the wound. The mortality tended to descend relevant to the position of the wounds, in the order of the head, chest, abdomen and limbs. CONCLUSIONS: Gunshot wound in seawater may cause severe hemodynamic changes, resulting in progressive dysfunction of circulation and high mortality rate. Early treatment should be targeted at hemodynamic stabilization in accordance to the characteristic changes during the early stages of the wound.  相似文献   
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林丽萍  卜君媛  梁爱萍 《护理研究》2005,19(14):1268-1269
妊娠期肝内胆汁淤积症(intrahepatic cholestasis of prenancy,ICP)是妊娠期特有的一种并发症,多发生于妊娠中期、晚期,表现为皮肤瘙痒和黄疸,主要危害胎儿,可导致早产、羊水胎粪污染及胎儿宫内窘迫,甚至死胎.目前已受到产科临床工作者的高度重视.我院自2000年1月-2004年11月收治ICP病人173例,经过积极治疗、严密监护、适时终止妊娠,母婴情况良好.现将有关护理总结如下.……  相似文献   
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