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31.
Abstract: A pulsatile impeller assist heart and a total heart were tested as a chronic left ventricular assist device in 5 calves and an acute biventricular assist device in 4 pigs respectively, to evaluate their blood compatibility. During the left ventricular assist experiments, the indicators for hemolysis, thrombogenesis, renal dysfunction, and hepatic dysfunction were measured preoperatively, at the beginning of the pumping, 6 h postoperatively, and every following day. The results demonstrated that the impeller assist heart causes no severe blood damage nor organ dysfunction in the experiments lasting up to 11 days. In biventricular assist experiments, the number of red blood cells, white blood cells, platelets, and the he-matocrit, hemoglobin, free hemoglobin, and lactate dehy-drogenase levels were tested preoperatively at the beginning of the pumping and every 2 h postoperatively. The data remained in acceptable ranges during experiments lasting 6 h. It is confirmed that the authors' impeller assist heart and total heart have the advantages of simplicity, implantability, and pulsatility with good blood compatibility. 相似文献
32.
用快速双抗体夹心ELISA检测囊虫病人血清中的循环抗原,其阳性率为67.5%;正常人血有的假阳性率为5.33%;包虫、肝吸虫和弓形虫病人血清的交叉反应率分别为6.9%、7.5%和12.5%。结果表明.该法与常规双抗体夹心ELISA相比具有较为敏感、快速、稳定和节省血清、试剂用量的优点,但其特异性有待进一步提高。用快速双抗体夹心ELISA和间接型ELISA检测第1至10疗程囊虫病人血清中的循环抗原和抗体,表明检测循环抗原考核囊虫病人的治疗效果优于检测抗体 相似文献
33.
由于病变和外伤等原因,使一些人眼球摘除,留下外现缺陷。医学上使用义眼台植入眼眶,在上面按装义眼以矫治外形。从前使用的义眼台用玻璃球或硅橡胶制作,使用中均有种类不同的缺点,即无生物活性、密度大等。医学界希望有新型医用材料临床应用。采用液态化学方法合成羟基磷灰石,使羟基磷灰石和微晶玻璃混匀,制成生物活性材料。生物材料和粘结剂、造孔剂,辅助剂一同制成生坯,以适当的温度焙烧成多孔结构义眼台。对材料进行了动物实验与临床应用。动物实验表明,材料具有优异的生物相容性和一定的生物活性。临床应用效果良好。本材料是制备义眼台的新材料。本文就材料研究、动物实验、义眼台的生产工艺进行了探讨。 相似文献
34.
Purification of antigenically intact Ro ribonucleoproteins; biochemical and immunological evidence that the 52-kD protein is not a Ro protein. 总被引:3,自引:0,他引:3
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G Boire M Gendron N Monast B Bastin H A Mnard 《Clinical and experimental immunology》1995,100(3):489-498
Anti-Ro sera immunoprecipitate Ro ribonucleoproteins (RNPs) from human cell extracts. Ro RNPs are biochemically heterogeneous particles whose functions are unknown and whose exact composition remains controversial. In addition to 60-kD Ro and to La proteins, a 52-kD polypeptide (p52) has been proposed to be a stable component of the Ro RNPs. To confirm the immunological studies supporting this hypothesis, we have biochemically purified Ro RNPs from HeLa cells using non-denaturing conditions. Ro RNPs segregated into three distinct populations, one of which only contained hY5 RNA (RohY5 RNPs). No p52 co-purified with Ro RNPs. Despite the absence of p52, purified Ro RNPs had biochemical and immunological properties identical to those of unfractionated Ro RNPs. Many anti-Ro sera only recognize p52 in immunoblots, and are said to be monospecific anti-p52. Preincubation with purified RohY5 RNPs (free of p52) of all human anti-Ro (including so-called monospecific anti-p52) sera abolished their capacity to immunoprecipitate Ro RNPs from unfractionated HeLa cell extracts. Conversely, preincubation of anti-Ro sera with purified p52 protein specifically inhibited recognition of p52 in immunoblots, but did not interfere with immunoprecipitation of Ro RNPs. Our data demonstrate that anti-p52 antibodies do not target intact Ro RNPs, nor do they target the native 60-kD Ro protein. Contrary to previous reports, p52 protein is not a stable component of antigenically intact Ro RNPs. 相似文献
35.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
36.
PROBLEM: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). METHOD: Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (<10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (>50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. RESULTS: Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. CONCLUSION: Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment. 相似文献
37.
含化复方新诺明引起过敏性休克一例患者,女,30岁,因咽峡炎于1992年8月7日晚10时自行含化复方新诺明(广州白云山制药厂)两片、约7分钟后,出现全身搔痒,当即肌注苯海拉明20mg,静推10%葡萄糖酸钙10ml,旋即全身泛起荨麻疹,奇痒难忍,眼睑轻度水肿,嘴唇发麻,咽部“发紧”,发音困难,烦躁,立即给予吸氧,静推地塞米松10mg,皮下注射肾上腺素0.5mg,与此同时,患者脸色苍白、鼻尖、未梢发凉,口唇紫绀,时吸暂停,意识丧失,脉搏140次/分,细数,血压测不到,再次给予皮下注射肾上腺素0.5mg,静点地塞米松15mg,并给予扩容、纠酸,约一分钟后,欲行气管切开时,患者呼吸渐恢复、继而意识清楚,紫绀减轻,血压10/16kPa,遂休克纠正。复方新诺明片致过敏性休克者尚属少见,该患者有青霉素过敏史,局部用药又易致过敏,考虑喉头痉挛与药物含化有关。(长治市人民医院王爱军,崔文华,郭天然)含化复方新诺明引起过敏性休克一例@王爱军,崔文华,郭天然$长治市人民医院 相似文献
38.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases
(pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating
capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions:
obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed
that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that
external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong
regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial
hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly
the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver.
This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry
of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation 相似文献
39.
40.
先天性输精管缺如患者生育问题的研究 总被引:1,自引:0,他引:1
自1988年至1991年共收治25例先天性输精管缺如患者,在20例行手术诊治术中15例用自体睾丸精索鞘膜制成人工精池囊,5例又在囊内放置用微涤纶制成的异质管。术中抽吸10例附睾内精子进行快速活化,其中5例活化成功,行人工授精,结果2例怀孕,1例已生育一女孩。认为该症是有生育可能的,但需要解决3个问题:(1)采用显微外科技术把附睾内部活着的精子取出一定数量;(2)选配好快速活化剂使精子快速活化成功;(3)用患者的精浆培养自己的精子。建议对梗阻性无精子症在用手术疏通精路的同时可以采用快速活化精子技术行人工授精,以提高生育的效果。 相似文献