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11.
慢性乙肝患者NK,ADCC活性及其对IFN—α,IFN—γ的反应   总被引:1,自引:0,他引:1  
白岚  孔宪涛 《免疫学杂志》1991,7(2):106-108
本文用Hela细胞乳酸脱氢酶释放法测定了42例慢性乙肝病人外周血NK、ADCC活性及其对IFN-α100U/ml、500U/ml及IFN-γ500U/ml预处理4小时后的反应。结果显示,病人PBL NK,ADCC活性与正常对照有显著差别,经IFNs处理后,其NK或/和ADCC活性均有不同程度的升高反应,从而提示了IFNs在慢性肝病治疗中的重要作用。  相似文献   
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The signal transduction pathways and activation of the MAP kinase or PI3 kinase signaling cascade regulate a variety of cellular processes, including proliferation and differentiation in hepatocytes. To elucidate the mechanisms of signal transmission required for the regulation of gap and tight junctions during DNA synthesis in rat hepatocytes, we determined changes of expression and function of gap and tight junctions of cells grown in primary culture, using inhibitors of signaling pathways for MAP kinase (PD98059) and PI3 kinase (LY294002). During the stimulation of DNA synthesis induced by epidermal growth factor (EGF), immunoreactivity and mRNAs of gap junction protein Cx32 and of tight junction protein claudin-1 markedly decreased with reduction of gap junctional intercellular communication (GJIC) and the fence function of tight junctions. In Western blots, whole-cell lysate of claudin-1 protein decreased and phosphorylated Cx32 protein in the insoluble fraction of Triton X-100 increased during the stimulation of DNA synthesis. During reinhibition of DNA synthesis, the changes of Cx32 and claudin-1 returned to control levels, as did both functions. In treatment with the inhibitors before DNA synthesis, PD98059 inhibited the changes of expression and function of Cx32, but not claudin-1, without inhibition of cell growth, whereas LY294002 completely inhibited cell growth. These findings indicate that the PI3 kinase pathway rather than the MAP kinase pathway plays an important role for EGF-induced proliferation of rat hepatocytes, and that changes of Cx32 in hepatocytes during the stimulation of DNA synthesis may be in part controlled through MAP kinase. Furthermore, Cx32, but not claudin-1, protein may be a target of activated MAP kinase in hepatocytes.  相似文献   
14.

Background  

Many candidate genes have been reported to be risk factors for acute coronary syndrome (ACS), but their impact on clinical prognosis following ACS is unknown.  相似文献   
15.
Chen YH  Lee MF  Lan JL  Chen CS  Wang HL  Hwang GY  Wu CH 《Allergy》2005,60(12):1518-1523
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens.  相似文献   
16.
BACKGROUND: Subthreshold electrical stimulation of the left stellate ganglion (LSG) can induce nerve sprouting and sympathetic hyperinnervation in canine ventricles. It is unclear whether a similar neural plasticity involving both sympathetic and parasympathetic innervation also exists in the atria. METHODS AND RESULTS: We applied subthreshold electrical stimulation at 20 Hz (0.45 ms pulse width) or 5 Hz (1.9 ms pulse width) to the LSG in 6 normal mongrel dogs. After 41+/-9 days, the hearts were harvested and the right and left atrium stained for synaptophysin (SYN), growth-associated protein 43 (GAP43), sympathetic nerve markers tyrosine hydroxylase (TH), and parasympathetic marker choline acetyltransferase (ChAT). Tissues from 6 additional healthy dogs were used as controls. The hearts from dogs with LSG electrical stimulation had a higher density of nerve structures immunopositive to the SYN, GAP43, TH, and ChAT (P<.01) in both right and left atria. Nerve density was equal in right and left atria. There were more TH-positive nerve structures than ChAT-positive nerve structures (P<.01) for both right and left atria. No atrial arrhythmia was observed at the second surgery. CONCLUSIONS: Continuous subthreshold electrical stimulation to the LSG induces both sympathetic and parasympathetic hyperinnervation in both right and left atria in normal dogs.  相似文献   
17.
针对医院资产管理的现状和难点,将平台中的空间管理同资产管理相结合,进行数据交互和功能拓展,不仅使医院空间和资产同步系统化、数据化,而且汇聚了资产管理全维度数据源,达到优化资源配置、降本增效的实践成果,也为建立基于云数据的资产设备全生命周期管理夯实基础。  相似文献   
18.
Akt/protein kinase B (PKB) plays an important role in cell survival. However, the role of Akt in the biology of gastric cancer has not been well studied. We sought to investigate the expression of Akt or phosphorylated Akt (pAkt) in human gastric carcinomas and to analyze the relationship between Akt or pAkt and the clinicopathologic parameters. The expressions of Akt and pAkt were evaluated immunohistochemically in 311 gastric carcinomas using the tissue array method. Akt expression was detected in 74% of the tumors and pAkt expression in 78%. pAkt was highly expressed in the early stage of pTNM (p=0.011). We also found an inverse association between pAkt and lymphatic invasion (p=0.01) or lymph node metastasis (p=0.008). pAkt expression was significantly correlated with a higher survival in patients with stage I carcinomas (p=0.0003). Interestingly, combined evaluation revealed that the group with pAkt-positive and lymph node-negative carcinomas showed a better prognosis than the other groups (p<0.0001). In addition, pAkt was shown to correlate positively with APC (p=0.002) and Smad4 (p<0.0001) expression. These findings suggest that pAkt expression may help to predict the clinical outcome of gastric cancer patients.  相似文献   
19.
通过对小鼠补体受体Ⅱ型基因(CR2)进行定点突变,然后将野生型和突变型小鼠CR2/1(MCR2/1)及人CR2(hCR2)用电穿孔方法导入小鼠SP2/0进行表达,采用免疫组织化学等方法鉴定阳性细胞系。用EB病毒对转染阳性细胞进行感染,EBER-1杂交结果显示,仅转染hCR2和突变型MCR2(mtMCR2)的SP2/0细胞感染了EB病毒,前者感染EB病毒的阳性率较后者高很多。这为进一步研究EB病毒进入细胞的机制及建立EB病毒相关的鼻咽癌动物模型奠定了良好的基础。  相似文献   
20.
目的:寻找番荔枝科假鹰爪属植物假鹰爪Desmos chinensis抗肿瘤活性成分。方法:采用硅胶柱色谱分离化学成分。根据理化性质及波谱分析等方法鉴定结构。结果:从氯仿萃取物中分离鉴定了7个化合物,分别是unon-al(Ⅰ),黄芩素-7-甲醚(Ⅱ),去甲氧杜鹃花素(Ⅲ),去甲氧杜鹃花素-7-甲醚(Ⅳ),苯甲酸(Ⅴ),β-谷甾醇(Ⅵ)和豆甾醇(Ⅶ)。结论:该种植中鉴定的黄酮类化合物均为β-环未取代,  相似文献   
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