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41.
To approach the action of modified Yu Ping Feng Tang(玉屏风汤 Jade-Screen Decoction)on cellularimmunity,an experiment was conducted in mice under amputation-induced stress.On the 3rd dayafter amputation,acute atrophy was found in the thymus,the reactivities of T-and B-lymphocytes toCon-A and LPS were decreased,the IL-2 content and its activity reduced and the activity of NK cellslowered.The high,moderate and low concentrations of the modified Yu Ping Feng(YPF)Decoction allhave antagonistic action on the above manifestations of immune inhibition.  相似文献   
42.
目的:探讨ATP敏感性钾通道(KATP通道)开放剂KRN2391(KRN)对离体大鼠心功能及心肌梗死范围的影响。方法:用Langendorff装置,观察不同浓度KRN对冠脉灌流量及左心室压力的影响。应用离体大鼠双冠脉分别灌注芊45min缺血及2h再灌注,观察药物对心肌梗死面积的影响。结果:KRN在达到1umol/L浓度后冠脉灌流量明显增加,达20umol/L时左室收缩压明显下降,用1umol/LK  相似文献   
43.
CD7 and CD57 are related to the differentiation and functional stages of CD8+ T cells. However, the role of their combined presence in CD8+ T cells in patients with chronic hepatitis B virus (HBV) infection, especially those with end-stage liver disease, remains unclear. Blood samples from healthy volunteers and patients with chronic hepatitis B were analyzed via Luminex assay and ELISA to measure plasma cytokine levels. Further, recombinant IL-22 was used to stimulate peripheral blood mononuclear cells from healthy volunteers, and the frequency of CD3+CD4CD7+CD57 T cells and apoptosis rates were investigated via flow cytometry. Patients with end-stage liver disease, particularly those with acute to chronic liver failure, showed decreased CD3+CD4CD7+CD57 T cell frequency. Furthermore, the prevalence of CD3+CD4CD7+CD57 T cells was negatively correlated with disease severity, prognosis, and complications (ascites). We also observed that IL-22 promoted apoptosis and brought about a decrease in the number of CD3+CD4CD7+CD57 T cells in a dose-dependent manner. CD3+CD4CD7+CD57 T cells displayed a B and T lymphocyte attenuator (BTLA)highCD25highCD127high immunosuppressive phenotype and showed low interferon-γ, tumor necrosis factor-α, granzyme A, and perforin expression levels. The present findings will elucidate the pathogenesis of HBV-related end-stage liver disease and aid the identification of novel drug targets.  相似文献   
44.
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST.  相似文献   
45.
EBV-associated nasopharyngeal cancer (NPC) occurs with high frequency in China and is a major cause of morbidity and mortality. To explore the potential use of adenovirus-mediated tumor suppressor p53 gene therapy In NPC, we first examined the in vitro effects of p53 introduced into the NPC cell lines RPMI 2650, Fadu and Detroit 562. p21(WAF1/CIP1) induction by chemotherapy was used as a functional assay which revealed that RPMI 2650 expresses wild-type p53 whereas Fadu and Detroit 562 encode mutant p53. Infection with p53-expressing adenovirus (Ad-p53) induced apoptosis and inhibited cell growth in all three NPC cell lines, regardless of the endogenous p53 status. Adenovirus infectivity was greatest in RPMI 2650 cells, with 100% of the cells expressing beta-galactosidase following Ad-LacZ infection using an MOI of 100, as compared to 20-30% infectivity with the other NPC lines. Using RPMI 2650 cells injected into nude mice, we developed an animal model for nasopharyngeal cancer. Established tumors (0.6-0.8 cm) were injected with 5x10(9) PFU Ad-LacZ, Ad-p53 or PBS in a 100 mu l volume. We found evidence for in vivo expression of beta-galactosidase or p53 and p21 up to two weeks following Ad-LacZ or Ad-p53 virus injection respectively. Objective regression of tumor size was observed at two weeks in 4/6 Ad-p53-treated tumors, but not in Ad-LacZ or PBS-treated tumors. The results provide an animal model for human nasopharyngeal cancer, and indicate a potential use of p53 in its therapy in vivo.  相似文献   
46.
由于我国医疗事故赔偿纠纷处理的有关法律、行政法规及司法解释之间存在着不统一、不配套的矛盾。因此,在审理医疗事故赔偿纠纷案件中的分歧颇大 这既不利于正确地维护医患双方的合法权益,也不利于医疗纠纷的顺利解决及社会秩序的稳定。因此,正确地认识与解决医疗事故赔偿纠纷法律适用中的矛盾,具有十分重要的意义。  相似文献   
47.
对原发性肝癌(PHC)81例;良性肝病58例;转移性肝癌11例;正常对照20例,进行血清标志物甲胎蛋白(AFP)、AFP异质体、5′-核苷酸磷酸二酯酶同工酶(5′-NPD)、唾液酸(SA)联合检测。结果显示四项标志物的组合能提高对PHC的诊断率(93.83%),同时还可用于小肝癌的诊断及PHC疗效观察及估计预后。  相似文献   
48.
Human papillomaviruses (HPVs) cause benign papillomas and squamous cell carcinomas in the genital and respiratory tracts. Recurrent respiratory papillomas (RRP) generate a high level of morbidity and significant mortality because of their location, resistance to treatment, and relentless recurrence that can vary in frequency in a given patient and between patients. We have found that T-cells from these patients, when exposed to or isolated from autologous papilloma tissue, have an elevated percentage of CD8(+), CD28(-) T-cells, and that T-cells from many of these patients express an increase in T(H)2-like cytokine mRNA in response to autologous papilloma tissue. Furthermore, both of these immunologic findings correlate with disease severity. These observations suggest that patients with RRP, and possibly others with refractory HPV-induced lesions, are unable to manage their disease with an appropriate and effective HPV-specific, T-cell response. This immune imbalance may be responsible for the development and severity of HPV-induced respiratory papillomatosis.  相似文献   
49.
Kong X  Zeng L  Xia T  Wang J  Mi P  Na Y  Xue Z  Pan B  Hao J  Gu F  Guo Y 《中华外科杂志》1999,37(4):231-234,I015
目的 探讨抑那通和缓退瘤联合治疗对正常前列腺,增生的前列腺(BPH)和前列腺癌以及睾丸的作用。方法 对16例接受联合内分泌治疗至少3个月且有治疗前后病理资料的前列腺癌患者的标本进行了系统的病理学检查。对内分泌治疗后的睾丸标本与同龄未接受治疗的进行对照研究。结果 14例内分泌治疗后的前列腺标本2例未见残存癌灶,9例对治疗有明显的反应;3例对治疗反应差,治疗并未降低前列腺癌的病理分期。3例内分泌治疗后  相似文献   
50.
雪旺氏细胞(Schwann cell,SC)在神经再生过程中起着重要作用。我们取人胚及兔之坐骨神经,采用“植块多次移出法”培养出纯净度达99%的人和兔的SC。对培养的SC进行了冻存和复苏处理,复苏后的细胞可保持原有的生长特性。  相似文献   
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