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51.
本研究采用牛房实验小屋,加装不透光百叶窗和透光门廊,从而全面观察药帘对侵入实验小屋蚊虫毒杀情况,包括蚊虫入屋前接触药帘时和屋内蚊虫外逸出屋外后的死亡情况。结果表明,澳氰菊酯、二氯苯醚菊酯毒效强和持效长,浸泡门窗帘后6个月18次试验,对侵入屋内蚊虫毒杀,平均死亡率分别为89.4%和90.6%。两药对入屋内蚊虫的吸血率均没有明显减少,可能与诱饵动物的吸引力有关。二氯苯醚菊酯有明显驱避作用,其减少蚊虫入屋率,按蚊为70.6%,库蚊为75.2%均没有明显减少,阿蚊却没有效应。  相似文献   
52.
目的:研制抗人喉癌/抗血管内皮因子(VEGF)双功能克隆抗体,用于喉癌抗血管生成治疗。方法:采用二次杂交瘤技术制备抗人喉癌/抗VEGF双功能抗体。经酶联免疫吸附试验法和SP法检测喉癌及癌前病患者血清及癌组织中VEGF的含量表达。结果:获得6株分泌抗人喉癌/抗VEGF双功能抗体的杂交瘤,经免疫组化证实与喉癌细胞特异性结合率为93%,而与血管内皮细胞结合率为89%。血清中VEGF含量表达,喉癌组与癌前病组及正常对照组相比差异均显著。IgG亚型鉴定为IgG2aBSAb抗体效价为1:25 600倍(ELISA法)。结论:二次杂交瘤法制备的双功能抗体具有均匀性、可控性、效价高、稳定性好,可用于喉癌抗血管生成治疗,动态检测可作为判断喉癌预后的客观指标。  相似文献   
53.
日本大耳兔9只,其中6~8月龄5只,2~2.5年龄4只。均喂以2%654-2溶液1ml/天(即20mg)共43天。结果不分年龄统计,LPO含最下降0.827±1.048 nmol/ml(P<0.05)。Na~+-K~+-ATPase活性增加0.057±0.074μmol Pi/mg pro/hr(P<0.05)。认为654-2可能有抗衰老作用,并与普鲁卡因比较,讨论了其降低LPO的可能途径。  相似文献   
54.
Patients' knowledge of their HIV condition and its treatment, which has been recognized as a factor that influences adherence to antiretroviral therapy, can be improved through educational programs. This prospective, randomized, controlled trial compared an experimental group that participated in an educational program and a control group with standard care. The study evaluated the impact of an educational intervention on adherence to antiretroviral therapy, patients' knowledge, quality of life, and therapeutic response in patients treated with highly active antiretroviral therapy. Three hundred twenty-six patients were analyzed at inclusion. A higher level of adherence was associated with patients who were older, had higher incomes, and did not smoke. CD4 cell count and plasma viral load were correlated with adherence at entry. The educational intervention had an impact on adherence and knowledge in the experimental group at 6 months, which was maintained at 12 and 18 months. A delayed increase in adherence was observed in the control group at 12 months. No significant impact on quality of life was observed over time. The patients' health status improved in 56% of the experimental group subjects and 50% of the control subjects. However, no significant impact was shown on CD4 cell count and plasma viral load. This study shows that an educational intervention improves adherence to antiretroviral regimens and health status and suggests that it should be initiated early in therapy.  相似文献   
55.
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   
56.
57.
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   
58.

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   
59.
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   
60.
将HRP微电泳人黑尾蜡嘴雀(Eophona mihratoria)端脑原纹状体粗核内,观察其传入性纤维联系.在下列部位发现有密集的逆行标记细胞:(1):原纹状体带核;(2)上纹状体腹侧尾核;(3)新纹状体前部大细胞核外侧部;(4)脑桥蓝斑.以上标记细胞均出现在同侧.结果表明,原纹状体粗核接受原纹状体带核、上纹状体腹侧尾核、新纹状体前部大细胞核外侧部及脑桥蓝斑的传入性投射.  相似文献   
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