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991.
A number of cytolytic T lymphocyte (CTL) clones derived from several melanoma patients have been found to recognize a majority of melanomas from HLA-A2 patients. We have reported previously that two such CTL clones recognize a product of the tyrosinase gene that is presented by HLA-A2. Here we show that one of these CTL clones recognizes a peptide encoded by the first nine amino acids of the putative signal sequence of tyrosinase. The other CTL clone recognizes a different tyrosinase peptide corresponding to amino acids 368–376. Both peptides contain consensus motifs of HLA-A2 binding peptides.  相似文献   
992.
Abstract: We performed a retrospective analysis of clinical course of 91 patients who developed both breast cancer and a chronic lymphoproliferative neoplasm and were seen at the M. D. Anderson Cancer Center between January 1, 1970 and December 30, 1991. The sample included 24 individuals who developed lymphoproliferative neoplasm first (Group A), 22 individuals with concurrent diagnosis of both malignancies (Group B), and 45 individuals who developed breast cancer first (Group C). The median time to diagnosis of secondary breast cancer and lymphoproliferative neoplasm was 66 months (range, 7–459) and 65 months (range, 0–334), respectively. A higher proportion of Group B lymphomas were low-grade (77% vs. 47% [Group A] vs. 37% [Group C] p = 0.009). Prior occurrence of either one of these malignancies did not affect the disease-specific survival from the second malignancy. However, continuing mortality from the first malignancy appeared to contribute to a poor overall survival following second malignancy. Group A included 8 patients who developed breast cancer following radiation therapy for Hodgkin's disease after a mean interval of 18 (± 4.3) years. Three of these individuals had coexisting ductal and lobular histology (vs. none of the individuals in Groups B and C, p = 0.02). Another interesting finding was the high incidence of multiple additional malignancies in this patient population. A total of 29 additional neoplasms occurred in 21 (23%) of the 91 study subjects. These malignancies involved a wide variety of organ sites and could not be attributed to the therapy for either the breast cancer or the lymphoma in most cases. The data suggest that individuals who develop both breast cancer and a lymphoproliferative neoplasm are at a high risk for multiple malignancies. Close surveillance of such individuals for additional malignancies and further studies to understand the molecular basis of this predisposition are warranted.?  相似文献   
993.
从脾论治磺脲类降糖药继发性失效   总被引:2,自引:0,他引:2  
对 64例 2型糖尿病继发磺脲类降糖药失效患者 ,在继续口服磺脲类药的基础上加用健脾中药 ,结果显效 1 5例 ,有效 3 6例 ,无效 1 3例 ,总有效率 85 .2 4% ;治疗前后血糖明显下降 ,有显著性差异 ( P<0 .0 0 1 )  相似文献   
994.
Summary Transcatheter inferior phrenic arterial (IPA) and hepatic arteriography was performed on 38 patients with advanced primary hepatic carcinoma (PHC) with blood supplied by IPA and hepatic artery. 18 patients received single treatment with hepatic arterial infusion (HAI) or embolization (HAE) 20 received double treatment with IPA and hepatic arterial infusion or embolization. The results show that the double treatment is superior to the single one. The angiographic features and mechanism of parasitization of inferior phrenic arterial supply to PHC were also discussed.  相似文献   
995.
在体外试验中研究了azimexon对小鼠脾细胞增殖以及白细胞介素2(IL-2)的影响。IL-2活性采用小鼠胸腺细胞增殖法和CTLL细胞增殖法测定。结果表明:azimexon单独不能增加脾细胞增殖和产生IL-2,但对亚适量ConA或LPS诱导的脾细胞增殖和产生IL-2有明显协同作用。  相似文献   
996.
During myogenesis in Drosophila embryos, a prominent adhesive structure is formed between precursor cells and fusion-competent myoblasts (fcms). Here, we show that Duf/Kirre and its interaction partners Rols7 (found in founder myoblasts and growing myotubes) and Sns (found in fcms) are organized in a ring-structure at the contact points of fcms with precursor cells, while cytoskeletal components like F-actin and Titin are centered in this ring in both cell types. The cytoplasmic protein Blow colocalizes with the actin plugs in fcms after cell adhesion. Furthermore, the requirement of additional as yet unidentified components was demonstrated by using mammalian C2C12 myoblasts. In this study, we propose that the fusion-restricted myogenic-adhesive structure (FuRMAS) is pivotal in linking cell adhesion as well as local F-actin assembly and dynamics to downstream events that ultimately lead to plasma membrane fusion. Moreover, we suggest that the FuRMAS may restrict the area of membrane breakdown.  相似文献   
997.
丹参抗大鼠乙酸性十二指肠溃疡作用机制的探讨   总被引:2,自引:0,他引:2  
目的 探讨丹参抗大鼠乙酸性十二指肠溃疡的作用及机制。方法 按Okabe方法复制大鼠乙酸十二指肠溃疡模型 ,按传统方法测定溃疡指数、溃疡抑制率 ;用放射免疫法测定十二指肠溃疡部位的前列腺环素 (PGI2 )含量。结果 丹参组的溃疡指数显著低于对照组 (P <0 .0 1) ,其溃疡抑制率高于对照组 ,PGI2 的含量亦显著高于对照组 (P <0 .0 1)。结论 丹参具有抗大鼠十二指肠溃疡的作用 ,其机制可能是丹参提高了十二指肠粘膜的防御能力  相似文献   
998.
AIMS: Scarcity of resources, expertise and evidence-based models have so far limited delivery of patient-centred diabetes education. We have developed and validated a group care approach that is applicable to everyday clinical practice and cost-effective in improving metabolic control, knowledge of diabetes, health behaviours, and quality of life in Type 2 diabetes. A clinical trial (ROMEO) was planned to evaluate applicability and reproducibility of group care in other outpatients facilities and assess its impact on a larger patient population. METHODS: Multicentre, randomized, controlled clinical trial of group vs. individual care in the routine management of Type 2 diabetes. Nine hundred patient aged < 80, with diabetes of > or =1 year known duration, treated by either diet alone or diet and oral agents, will be recruited in 15 centres and followed for 4 years. Training of physicians, nurses and dietitians included preparation of operating manual and videos, interactive sessions, and evaluation of local facilities and resources. RESULTS: Primary measurements: 3-monthly HbA1c, fasting blood glucose, body weight, waist-hip ratio, yearly blood lipids, and bi-yearly assessment of knowledge of diabetes, health behaviours and quality of life. Secondary outcomes: systolic and diastolic blood pressure, evaluation of ECG for ischaemia and QT interval, hypoglycaemic and anti-hypertensive medication and cardiovascular events. Analysis will be by intention-to-treat. DISCUSSION: If ROMEO confirms that group care can be successfully implemented in different clinics, a novel clinico-pedagogic tool will have been acquired to support patient-centred education, improve lifestyle and outcomes, support team work, enhance providers' attitudes and competencies and ameliorate diabetes care organization.  相似文献   
999.
目的:观察三氧化二砷(As2O3)和全反式维甲酸(ATRA)联合作用对NB4,MR2不同亚型急性早幼粒白血病细胞株,诱导分化、增殖、凋亡的影响。方法:以NB4,MR2为体外模型,利用细胞生长曲线、台盼蓝拒染法、MTT法、NBT、细胞形态Wrigh‘s-Gimesa染色,观察细胞增殖、分化、凋亡的相互作用。结果:NB4细胞株:0.5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现拮抗,而0.5μmol/L As2O3与(10^-7--10^-8mol/L)ATRA呈现协同;MR2细胞株:0.5μmol/L As2O3与10^-6mol/L ATRA对细胞增殖、分化、凋亡呈现协同。结论:As2O3与全反式维甲酸协同效应呈现不同细胞、剂量的特异性,MR2细胞株协同效应明显强于NB4细胞株。  相似文献   
1000.
心肌缺血再灌注损伤时细胞核被膜钙泵活性特征的研究   总被引:1,自引:0,他引:1  
目的 研究心肌缺血再灌注损伤时Ca2 + 、ATP、ADP和AMP对细胞核被膜钙泵 (Ca2 + ATPase)活性的调节。方法 采用大鼠心肌缺血再灌注模型 ,密度梯度分离纯化细胞核 ,定磷法测定Ca2 + ATPase活性。结果 与正常大鼠相比 ,缺血再灌注损伤动物血浆MDA和FFA显著升高 (P <0 0 1) ;细胞核Ca2 + ATPase活性下降 ,对Ca2 + 亲和力降低 ;ADP、AMP对核Ca2 + ATPase活性的影响明显减弱 ;ATP对Ca2 + ATPase的作用在 [ATP]小于 1 0mmol L时 ,与正常细胞Ca2 + AT Pase活性无显著差异 ,浓度增至 2 0mmol L时 ,活性低于正常细胞 ,ATP浓度继续增加 ,核Ca2 + ATPase活性快速增加。结论 心肌缺血再灌注损伤时Ca2 + 、ATP、ADP、AMP对心肌细胞核Ca2 + ATPase活性的影响发生了明显改变 ,其病理生理意义值得进一步探讨。  相似文献   
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