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101.
本文通过犬急性心肌缺血-再灌注模型探讨缺血-再灌注心肌Ca2+超负荷的发生机制。当心肌持续缺血150min,心肌细胞内Ca2+、Na+增加、K+降低;心肌细胞膜Na+-K+-ATPase、Ca2+-ATPase活性降低,心肌组织丙二醛(MDA)含量增加.而心肌缺血90min后,再灌注60min,与之比较细胞内Ca2+明显增加,伴Na+升高、K+降低,心肌细胞膜Na+-K+-ATPase、Ca2+-ATPase活性降低,MDA含量增加,说明缺血-再灌注过程中Na+升高、Na+-Ca2+交换增加,Ca2+-ATPase活性降低是细胞内Ca2+超负荷发生的重要原因。  相似文献   
102.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。  相似文献   
103.
We have advanced the hypothesis that the primary autolymphoproliferative response of dog T cells in mixed lymphocyte kidney cultures (MLKC) results from their recognition of tissue-specific (kidney-associated) antigen(s) presented in conjunction with class II MHC antigens. Lymphocyte culture-derived supernatants had been found previously to upregulate class II antigen expression on kidney cells and enhance T cell activation. In the present study we have isolated and characterized dog IFN-gamma, a class II-inducing substance that is secreted in the culture supernatant of activated T lymphocytes. Dog IFN-gamma was induced with A-23187 and PMA and purified stepwise using controlled-pore glass, Mono Q anion exchange chromatography, and Superose 6-gel filtration on FPLC. The purification resulted in two molecules of 42 Kd and 31 Kd molecular weights. An IgG1 monoclonal antibody was engendered to these molecules. With this mAb reagent, in immunochemical experiments, we have developed a sensitive ELISA and a method for purifying dog IFN-gamma by affinity chromatography. Species specificity studies indicated that purified dog IFN-gamma reacted with a polyclonal rabbit antihuman IFN-gamma, but not with a mAb to human IFN-gamma. However, the antidog IFN-gamma mAb that was generated also reacted with recombinant human IFN-gamma. In in vitro biological studies, the purified IFN-gamma (two mol. wt. species) upregulated the expression of canine class II MHC molecules on dog tubular epithelial cells and the dog kidney epithelial cell line (MDCK). The antidog IFN-gamma mAb blocked T cell proliferative response to kidney cell and, by inference, the interaction between endogenously released IFN-gamma in vitro with its cell surface receptor, thus inhibiting the induced upregulation of class II. Interestingly, although antidog IFN-gamma markedly blocked the MLKC (10 micrograms mAb/well), there was no effect on the allogeneic MLC. This observation indicates that the cytokine IFN-gamma may be a uniquely key substance amplifying the immune response of T cells to tissue-associated antigens on surrogate antigen-presenting cells that require induced upregulation of class II MHC antigen expression (MLKC), in contrast to reactions in which these antigens are already constitutively expressed on the antigen-presenting cells (mixed lymphocyte culture).  相似文献   
104.
目的:了解近年来泌尿系细菌感染致病菌及耐药性,为合理应用抗生素,提供临床根据。方法:对泌尿系感染患者298株病原菌进行药物敏感试验。结果:大肠埃希菌仍是引发泌尿系感染的主要病原菌,占53%,其次是葡萄球菌属,占19.40%,肠杆菌属占10.06%,肠球菌属占4.70%等,各类菌属耐药情况。结论:临床医师必须关注本地病原菌分布及耐药情况,合理应用抗生素,减少耐药性播散。  相似文献   
105.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
106.
Assessment of carbohydrate tolerance in pregnancy   总被引:4,自引:0,他引:4  
A review is given of the various methods of assessing carbohydrate tolerance in pregnancy. Oral glucose tolerance screening and diagnostic tests have been in use for more than 25 years. They are easily administered, relatively inexpensive, and present reasonable sensitivity; therefore, they continue to be used quite extensively. However, lack of reproducibility of the results and side effects such as nausea, vomiting, and headache have led to the use of alternate methods including glucose polymer (Polycose) and standard breakfast meals. These methods have been reported to present satisfactory results in clinical practice. Glycosylated hemoglobin (HbA1c) and fructosamine assays are also alternate forms of testing carbohydrate metabolism HbA1c measurement have been proven insensitive as a screening test for gestational diabetes, while their use as an index of overall glucose control remains valuable. The role of fructosamine in the assessment of carbohydrate intolerance remains controversial with conflicting claims made by various investigators regarding its sensitivity in detecting gestational diabetes and its response to alterations in glycemic control. In this review, the relative advantages and disadvantages of each glucose tolerance test are discussed and recommendations are given regarding their utility in pregnancy.  相似文献   
107.
哈乐在良性前列腺增生伴急性尿潴留中的应用   总被引:5,自引:0,他引:5  
目的 :探讨α1A肾上腺素能受体阻滞剂哈乐 (tamsulosin)对良性前列腺增生 (BPH)伴急性尿潴留病人的治疗作用。方法 :对 72例BPH伴急性尿潴留病人采用随机、对照研究 ,分为治疗组和对照组。病人均行保留导尿 ,口服抗生素治疗。治疗组加用哈乐 0 .4mg ,1次 /d ,连续服用 3次。 72h后拔除导尿管。 结果 :拔除导尿管后 4 4 % (32 / 72 )的病人能自行排尿。有效率治疗组为 6 1% (2 2 / 36 ) ,对照组为 2 8% (10 / 36 ) ,两组比较差异有显著性 (P <0 .0 1)。 结论 :对BPH伴急性尿潴留应用哈乐治疗 ,可提高早期拔除导尿管后病人自行排尿的成功率 ,且疗效与前列腺体积大小无关。  相似文献   
108.
目的了解流行性出血热病毒(EHFV)对心脏的损害情况。方法对103例流行性出血热(EHF)患者的心电图及心肌酶学检测结果进行分析。结果72例(69.9%)患者出现心电图异常,以窦性心动过缓(27.9%)及窦性心动过速(22.3%)最常见,明显高于其它类型的心电图改变(P分别<0.05和0.001)。103例流行性出血热(EHF)患者的CK、LDH及HBDH的升高者分别为43例(41.2%)、73例(70.9%)及46例(44.7%),以LDH异常最常见。轻型、中型、重型及危重型流行性出血热患者的LDH值分别为(346.3±155.6)IU/L、(330.7±130.7)IU/L、(1114.4±872.4)IU/L及(1227.1±936.7)IU/L,经统计学处理重型及危重型的值与轻型、中型比较均有显著性或高度显者性差异。结论EHF患者并发心肌损害较普遍,而且病情愈重者,心肌损害愈严重。  相似文献   
109.
关于课堂多媒体教学的思考   总被引:10,自引:1,他引:9  
多媒体教学已成为课堂教学的一种常用手段,多媒体教学应从实际需要出发,以提高教学效果为目标;需要教师掌握多种计算机及多媒体知识技能,科学地进行教学设计;教学过程中应发挥多媒体的优势,注重师生交流。对此本文进行了探讨。  相似文献   
110.
中重型β地中海贫血基因类型分析   总被引:1,自引:0,他引:1  
目的 了解中间型和重型β地中海贫血基因突变类型及其相关血液,生化变化。方法 应用反向点杂交法检测16种β地贫点突变基因,常规进行血细胞分析及其他地贫筛查试验。结果 27例中重型β地贫患者中10例为纯合子,17例为双重杂合子,10例纯合子中5例CD41-42纯合子,占50%,3例TATAnt-28纯合子,占30%;CD17纯合子和IVS-nt654纯合子各1例,各占10%,17例双重杂合子中5例为IVS-nt654/CD41-42占29.4%,3例为CD17/CD41-42,占17.6%;3例为TATAnt-28/CD41-42,占17.6%;2例为βE/IVS-nt654,占11.6%;CD17/TATAnt-28,IVS-nt654/CD17,IVS-nt654/CD1-1,1CD71-72/IVS-nt654各1例,各占5.9%。27例患者血红蛋白均低于90.0g/L。平均为58.8g/L;平均MCV为65.0fl。脆性均少于60%。结论 中重型β地中海贫血基因突变类型多样,组合类型不同,临床表现轻重不一,多呈中重度贫血,血液,生化均有明显改变,多需输血维持生命,故应做好产前诊断,预防其出生。  相似文献   
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