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目的 研究大网膜脂肪组织中肿瘤坏死因子(TNF)-α基因的表达及其在肥胖和胰岛素抵抗发病机制中的作用。方法 (1)选择肥胖合并胰岛素抵抗患(体重指数,BMI<30kg/m^2,空腹血浆胰岛素>20μIU/ml,疾病组)和对照组(BMI<25mg/m^2)各10例,抽提大网膜脂肪组织RNA。(2)用半定量RT-CPR方法研究两组大网膜脂肪组织中TNF-α基因的表达。结果 (1)疾病组中TNF-αRNA水平显著高于对照组(P<0.01)。结论 (1)疾病组大网膜脂肪组织中TNF-α表达增多,由于TNF-α能抑制脂肪细胞堆积,因此这可能是机体的保护反应;(2)肥胖患者中可能存在TNF-α限制脂肪堆积中作用减弱,从而产生肥胖。  相似文献   
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National abortion laws usually do not allow abortion when a foetus is independently viable, i.e. from a gestational age of about 24 weeks. Fetal anomalies, which may be a reason to seek abortion, are sometimes detected only in an advanced stage of pregnancy. National legislatures who want to allow 'late' abortion need to account for the protection the fetus may derive from the European Convention for the protection of human rights. As yet it remains unclear to what extent the fetus can in fact derive protection from the Convention, although several national abortion laws have been tested against it by the European Commission. The significance of the reports of the Commission on the question whether national legislation allowing abortion of a viable fetus is in conflict with the Convention, is explored. It is concluded that there is no European legal standard in terms of duration of pregnancy to which national legislatures are committed.  相似文献   
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PURPOSE: To determine whether there is an age-related increase of pentosidine in human Bruch's membranes and to localize pentosidine and carboxymethyllysine (CML), two well-characterized, advanced glycation end products (AGEs) in aged human Bruch's membranes and choroid in vivo. METHODS: Human Bruch's membrane samples were isolated from the retinal pigment epithelium (RPE) and choroid and subjected to reversed-phase high-performance liquid chromatography to determine pentosidine content. A polyclonal anti-pentosidine antibody and a monoclonal antibody specific for carboxymethyllysine were used to localize AGEs in 20-month-old nondiabetic, 82-year-old nondiabetic, and 82-year-old diabetic globes. RESULTS: Human Bruch's membranes (n = 20) showed a linear age-dependent increase in pentosidine that reached approximately 0.17 millimoles pentosidine per mole hydroxyproline in late life (r = 0.896; P < 0.001). Immunohistochemical evaluation showed evidence of pentosidine in Bruch's membrane, choroidal extracellular matrix, and vessel walls in the 82-year-old nondiabetic and diabetic globes. A similar staining pattern was found with the anti-CML antibody. Basal laminar deposits and drusen stained with both antibodies in the elderly nondiabetic eye. In contrast, neither antibody stained the 20-month-old tissue. CONCLUSIONS: We provide biochemical and immunohistochemical evidence for the formation of pentosidine and CML structures in human Bruch's membrane and choroid with age. These changes could promote aging of the RPE-Bruch's membrane-choroid complex.  相似文献   
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Gemtuzumab ozogamicin (Mylotarg) induces remission in approximately 30% of relapsed AML patients. We previously demonstrated that gemtuzumab infusion results in near-complete CD33 saturation in peripheral blood, and that saturating gemtuzumab levels result in continuous binding and internalization of gemtuzumab due to renewed CD33 expression. We now demonstrate that a high CD33-antigen load in peripheral blood is an independent adverse prognostic factor, likely due to peripheral consumption of gemtuzumab. Indeed, CD33 saturation in bone marrow is significantly reduced (40-90% saturation) as compared with CD33 saturation in corresponding peripheral blood samples (>90%). In vitro, such reduced CD33 saturation levels were strongly related with reduced cell kill. Apparently, high CD33-antigen loads in blood consume gemtuzumab and thereby limit its penetration into bone marrow. Consequently, CD33 saturation in bone marrow is reduced, which hampers efficient cell kill. Therefore, gemtuzumab should be administered at higher or repeated doses, or, preferably, after reduction of the leukemic cell burden by classical chemotherapy.  相似文献   
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Brake M  Loertzer H  Horsch R  Keller H 《Urology》2000,55(5):673-678
OBJECTIVES: To examine in a prospective study the incidence of recurrence and progression in patients with Stage T1 bladder carcinoma after complete transurethral resection of the bladder tumor and adjuvant immunotherapy with bacillus Calmette-Guérin (BCG). METHODS: Between July 1987 and April 1999, 126 patients presenting to our clinic with a superficial urothelial carcinoma of the bladder (Stage pT1, grade 1-3) received adjuvant intravesical immunotherapy with BCG after complete transurethral resection of the bladder tumor. In the case of recurrence of superficial tumor (pTa, pT1, or carcinoma in situ), patients received a second cycle of BCG. For muscle-invasive tumor progression (pT2, pT3, or pT4), radical cystectomy was recommended. Six of the patients (5%) presented with Stage pT1,G1 tumor, 74 (59%) with Stage pT1,G2 tumor, and 46 patients (36%) with Stage pT1,G3 tumor. Median follow-up was 53 months (range 3 to 144). RESULTS: One hundred eight patients (86%) remained tumor-free with a retained bladder during the follow-up after one or two 6-week cycles of BCG. Twenty-four patients (19%) had a recurrence of superficial tumor, 13 (10%) had muscle-invasive progression after the first BCG cycle, and an additional 4 (3%) had progression after the second BCG cycle. Six patients (5%) underwent radical cystectomy, and 9 patients (7%) died as a result of tumor progression. The tumor-free survival rate of all patients was 89% (112 of 126). CONCLUSIONS: Adjuvant immunotherapy with BCG after complete transurethral resection of the bladder tumor represents a highly effective primary treatment for Stage T1 carcinoma of the bladder. Even in Stage pT1,G3 tumor, immediate radical cystectomy does not appear necessary.  相似文献   
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PURPOSE: We prospectively examined the incidence of recurrence and progression in patients with stage pT1, grade 3 carcinoma of the bladder following complete transurethral resection of the bladder tumor and adjuvant immunotherapy with bacillus Calmette-Guerin (BCG). MATERIALS AND METHODS: Between July 1987 and March 1999, 123 patients presenting to our clinic with superficial urothelial carcinoma (stage pT1, grades 1 to 3) received adjuvant intravesical immunotherapy with BCG after histologically confirmed complete transurethral tumor resection. Disease was stage pT1, grade 3 in 44 patients (36%). Median followup was 28 months (mean 43, range 5 to 141). RESULTS: Of the patients 36 (82%) with bladder preservation remained tumor-free during followup after 1 or 2 cycles of BCG. Superficial tumor recurred in 5 patients (11%) and muscle invasive progression was noted in 7 (16%). Radical cystectomy was performed in 4 cases (9%). Of the patients 5 (11%) died of cancer. Tumor-free survival for all patients was 89% (39 of 44). CONCLUSIONS: Adjuvant immunotherapy with BCG after complete transurethral resection of bladder tumor represents a highly effective primary treatment of stage pT1, grade 3 carcinoma of the bladder. Immediate radical cystectomy does not appear necessary.  相似文献   
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RNA viruses, such as foot-and-mouth disease virus (FMDV), have error-prone replication resulting in the continuous emergence of new viral strains capable of evading current vaccine coverage. Vaccine formulations must be regularly updated, which is both costly and technically challenging for many vaccine platforms. In this report, we describe a plasmid-based virus-like particle (VLP) production platform utilizing transiently transfected mammalian cell cultures that combines both the rapid response adaptability of nucleic-acid-based vaccines with the ability to produce intact capsid epitopes required for immunity. Formulated vaccines which employed this platform conferred complete protection from clinical foot-and-mouth disease in both swine and cattle. This novel platform can be quickly adapted to new viral strains and serotypes through targeted exchanges of only the FMDV capsid polypeptide nucleic acid sequences, from which processed structural capsid proteins are derived. This platform obviates the need for high biocontainment manufacturing facilities to produce inactivated whole-virus vaccines from infected mammalian cell cultures, which requires upstream expansion and downstream concentration of large quantities of live virulent viruses.  相似文献   
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