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51.
毛慧生  宁连胜 《中国肿瘤临床》1992,19(3):174-179,240
应用激光多普勒血流仪测量比较津白Ⅱ号小鼠三个部位皮肤的血流,观察HDZ对血流的影响,评价了HDZ的体内热增敏作用。结果发现,同一小鼠不同部位的血流是不同的,同一部位的连续6天结果无何区别。但同部位小鼠间的血流差别可达1倍以上。提示了预测放、化、热疗的疗效时,监测个体血流的前后变化有重要意义。2.5mg/kg以上的HDZ可以明显降低血流75%左右。HDZ与高温联合应用时对肿瘤显示了热增敏效应。  相似文献   
52.
应用抗猪囊虫抗原的单克隆抗体反向间接血凝试验(IHAT),对临床确诊的囊虫病患者进行了血清循环抗原(CAg)的检测,阳性率为51.14%(67/131)。对19例脑型囊虫病患者同时测定了血清和脑脊液中的CAg,阳性率分别为47.36%和78.94%,总阳性率为84.21%。对治疗0.53后的19例患者检测时,血清和脑脊液中CAg均呈阴性反应,而检测抗体仍呈阳性反应。50例正常人、49例其它寄生虫病及5例其它脑部疾病患者脑脊液的CAg均呈阴性反应。结果提示:测定CAg对囊虫病活动性感染的诊断及疗效判定均具有一定的实用价值。  相似文献   
53.
本文报道3-50岁214例心导纳微分环(CADL)和肺导纳微分环(PADL)最大向量振幅及方位正常值,结果随增龄变化振幅递减,方位递增,多数男>女,部分组间有差异。48例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系,并探讨其临床意义。  相似文献   
54.
C Y Mao 《中华外科杂志》1990,28(1):24-8, 61
Forty cases of severe pancreatitis confirmed and treated by surgery were studied. In order to have a retrospective observation, we compared the clinical and laboratory data of 28 severe cases with that of 72 mild cases treated conservatively and found that in some cases neither Ranson nor Bank criteria were reliable in predicting the severity. We also found that frank peritonitis and bloody ascites with elevated amylase level were very good indication of pancreatic necrosis and hemorrhage. It was the author's opinion to explore early within 48 hrs after onset, using both drainage and open lesser sac lavage in most severe cases of pancreatitis.  相似文献   
55.
OBJECTIVE: To study the effect of eucalyptus globulus oil on the activity of nuclear factor-kappaB(NF-kappaB) in THP-1 cell line. METHODS: THP-1 cells were cultured with or without eucalyptus globulus oil at different concentrations (1, 10, 100 mg x L(-1), 30 min) before being stimulated with lipopolysaccharide (LPS, 1 mg x L(-1), 30 min). The location of NF-kappaB p65 subunit (NF-kappaB/p65) in THP-1 cells was detected by indirect immunofluorescence and laser scanning confocal microscope. The expression of NF-kappaB/p65 in nuclei was measured by Western-blot analysis. RESULT: The FITC-label NF-kappaB/p65 was mainly located in the nuclei after THP-1 cells were stimulated with LPS. Whereas, no fluorescence were seen in the nuclei of cells pretreated with eucalyptus globulus oil. This effect on NF-kappaB/p65 nuclear translocation was in a concentration dependent manner. CONCLUSION: Eucalyptus globulus oil inhibits the nuclear translocation of NF-kappaB induced by LPS in THP-1 cells.  相似文献   
56.
57.
胸腺切除后血清乙酰胆碱受体抗体改变及与疗效关系   总被引:2,自引:0,他引:2  
随访23例因重症肌无力行胸腺切除术的病人。运用灵敏度高、特异性强的BAS—ELISA法检测手术前、后血清乙酰胆碱受体抗体(AchR抗体)水平,所得结果均进行统计学分析。23例病人胸腺切除后,18例临床症状改善,有效率78%。术后14例(61%)病人血清AchR抗体水平下降,统计结果表明,手术前后血清AchR抗体水平差异有显著性(P<0.05),但与症状改善无关(P>0.05)。手术前后血清AchR抗体水平不影响疗效(P>0.05)。  相似文献   
58.
宫颈粘液过氧化物酶在月经周期中的变化规律   总被引:3,自引:1,他引:2  
本文对29例月经周期正常妇女的宫颈粘液过氧化物酶进行了30个周期的研究。在月经周期不同时间测定宫颈粘液过氧化物酶(CMPx)活性及血清促黄体生成素(LH)、雌二醇(E_2)和孕酮(P)。结果表明:在排卵前三天酶活性明显下降,至排卵后一天开始上升。卵泡期,酶活性与E_2呈负相关(r=-0.67);黄体期,酶活性与P呈正相关(r=0.79)。本研究提示:1.CMPx在排卵周期具有特定的变化规律,其变化受体内激素水平影响,可作为预告排卵的指标。2.如简化测定方法,可为自然避孕提供新途径。  相似文献   
59.
Linkage studies indicate close associations of certain HLA alleles with autoimmune diseases. To better understand how specific HLA alleles are related to disease pathogenesis, we have generated an HLA DR3/DQ2 transgenic mouse utilizing a 550-kb yeast artificial chromosome (YAC) construct containing the complete DRalpha, DRbeta1, DRbeta3, DQalpha, and DQbeta regions. The transgenic mouse (4D1/C2D) in an I-Abeta(o) background appears healthy with no signs of autoimmune diseases. Lymphoid tissues as well as CD4(+) T cells develop normally. Characterization of the transgene expression demonstrates that approximately 90% of B cells express high levels of DR3 and 50-70% of B cells express DQ2. CD11c(+) dendritic cells express high levels of DR and DQ. Approximately 12-18% of resting T cells are positive for DR expression, and further up-regulation to 40-50% expression is seen upon activation with anti-CD3/anti-CD28 mAb. These results suggest that the transgenic construct confers a high fidelity to the normal human temporal and spatial expression profile. Analysis of T cell receptor repertoire in transgenic mice confirms that DR3/DQ2 are able to mediate thymic selection. Furthermore, transgenic mice respond to a DR3-restricted antigen, demonstrating antigen processing and presentation by antigen-presenting cells (APC). Purified T cells from ovalbumin (OVA)-immunized 4D1 mice respond to human APC co-cultured with OVA, suggesting appropriate antigen/DR3 or DQ2 recognition by murine T cells. Immunoglobulin isotype switching is also observed, indicating functional T-B cognate interactions. Thus, the DR3/DQ2 transgenic mouse has normal lymphoid development and functionality that are mediated by HLA transgenes and can be used to investigate HLA-associated immunological questions.  相似文献   
60.
Committing embryonic stem cells to early endocrine pancreas in vitro   总被引:12,自引:0,他引:12  
A panel of genetic markers was used to assess the in vitro commitment of murine embryonic stem (ES) cells toward the endoderm-derived pancreas and to distinguish insulin-expressing cells of this lineage from other lineages such as neuron, liver, and yolk sac. There are two nonallelic insulin genes in mice. Neuronal cells express only insulin II, whereas the pancreas expresses both insulin I and II. Yolk sac and fetal liver express predominately insulin II, small amounts of insulin I, and no glucagon. We found that ES-derived embryoid bodies cultured in the presence of stage-specific concentrations of monothio-glycerol and 15% fetal calf serum, followed by serum-free conditions, give rise to a population that expresses insulin I, insulin II, pdx-1 (a pancreas marker), and Sox17 (an endoderm marker). Immunohistochemical staining shows intracellular insulin particles, and its de novo production was confirmed by staining for C-peptide. Most, but not all, of the insulin+ or C-peptide+ cells coexpress glucagon, demonstrating a differentiation pathway to pancreas rather than yolk sac or fetal liver. Addition of beta-cell specification and differentiation factors activin beta B, nicotinamide, and exendin-4 to later-stage culture increased insulin-positive cells to 2.73% of the total population, compared with the control culture, which gave rise to less than 1% insulin-staining cells. These findings suggest that stepwise culture manipulations can direct ES cells to become early endocrine pancreas.  相似文献   
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