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Fasting up-regulates central orexigenic systems including orexin A and neuropeptide Y (NPY) and it also inhibits the secretion of prolactin. We hypothesized that fasting may act through orexin A and NPY to influence tuberoinfundibular dopaminergic (TIDA) neurones, the major regulator of prolactin secretion. The effects of orexin A and NPY on TIDA neuronal activity and prolactin secretion were determined in oestrogen-primed ovariectomized rats, and the effects of fasting and the involvement of orexin A and NPY were tested. Orexin A, NPY and its analogs were administered through preimplanted intracerebroventricular (i.c.v.) cannulae. TIDA neuronal activity was determined by measuring concentrations of 3,4-dihydroxyphenylacetic acid (DOPAC) or 3,4-dihydroxyphenylalanine in the median eminence. i.c.v. injection of NPY (10 microg) or orexin A (1 microg) concomitantly increased median eminence DOPAC and decreased serum prolactin concentrations. The effect of NPY was mimicked by a Y1 receptor agonist at lower doses (0.1 and 1 microg) and no additive effect was observed when orexin A and the Y1 agaonist were coadministered. Moreover, a Y1 receptor antagonist, BIBP, not only blocked the effect of Y1 agaonist, but also that of orexin A. Treatment with BIBP alone decreased median eminence DOPAC and increased serum prolactin concentrations, indicating that endogenous NPY may play a role. Moreover, fasting for 48 h significantly increased TIDA neuronal activity, both in the morning and afternoon, and the effect was reversed by treatment with either BIBP or an antibody against orexin A. The findings support our hypothesis that fasting stimulates TIDA neuronal activity and inhibits prolactin secretion through up-regulated central orexin A and NPY systems.  相似文献   
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Background We have observed prolonged survival in patients undergoing vaccine reinduction after resection of recurrent metastatic melanoma and adjuvant polyvalent allogenic cell vaccine (PACV) immunotherapy. We hypothesized that reinduction with a more intensive vaccine regimen would re-stimulate specific immune responses that were correlated with survival after recurrence. Methods From 1996 to 1998, 194 patients developed recurrence during adjuvant PACV (CancerVax vaccine) treatment after resection of metastatic melanoma. Recurrent disease was treated with or without vaccine reinduction. Reinduction regimen entailed an increased vaccine frequency and coadministration of two doses of bacille Calmette-Guérin (BCG). PACV Delayedtype hypersensitivity (DTH) responses were prospectively recorded. Survival was defined as the interval from recurrence to death. Results Ninety-four patients underwent reinduction immunotherapy. DTH responses to PACV before recurrence increased significantly after reinduction therapy (P=.0001). The median survival time was 37 months for reinduced patients and 17 months for other patients. On multivariate analysis, reinduction status remained a significant prognostic variable (P=.0277). In the reinduction group, there was a significant correlation between PACV DTH responses and survival (P=.0178). Conclusions Reinduction vaccine regimen can enhance immune responses in previously immunized patients and is associated with prolonged survival after recurrence in patients receiving the same active specific immunotherapy. Presented at the Society of Surgical Oncology annual meeting. Washington, DC, March 15–18, 2001.  相似文献   
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社区健康教育对糖尿病治疗效果评价   总被引:8,自引:0,他引:8  
目的:探讨合理的健康教育对乙型糖尿病患者病情控制的影响,为今后更好开展社区糖尿病医护服务摸索方法。方法:按照实验流行病学调查的方法,将12 1名患者随机分为对照组和干预组,在干预组实施糖尿病综合干预措施。结果:干预组经综合干预后知识水平有明显提高(P <0.0 5 ;血糖控制水平明显优于对照组(P <0.0 1) ,患者对治疗依从性显著提高。结论:糖尿病教育对于社区预防和治疗糖尿病有非常重要的意义  相似文献   
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刘梅梅  隋丽华  李佩玲  程丽  李文辉 《肿瘤》2006,26(10):905-909
目的:探讨内皮抑素对卵巢癌SKOV3细胞及其荷瘤鼠卵巢癌组织的生长作用及机制。方法:MTT法观测内皮抑素对体外SKOV3细胞的抑制作用,透射电镜观察细胞凋亡、免疫细胞化学检测SKOV3;细胞中bcl-2和bax蛋白表达;将SKOV3细胞移植至裸鼠皮下,观察内皮抑素对皮下移植瘤生长的影响;TUNEL和电镜法观察肿瘤细胞的凋亡,免疫组织化学和RT-PCR法检测瘤组织中bcl-2和bax的表达。结果:内皮抑素具有体外抑制SKOV3细胞增殖的作用(P<0.01);能诱导SKOV3细胞凋亡,但对bcl-2和bax的表达无明显影响。内皮以抑素能抑制裸鼠皮下移植瘤的生长(P<0.05);其中bcl-2的表达低于对照组,而bax表达无明显改变。结论:内皮抑素具有抑制SKOV3细胞及皮下移植瘤生长的作用,其机制可能与诱发细胞凋亡和调节bcl-2/bax表达相关。  相似文献   
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The purpose of this study was to investigate the value of using MRI with integrated endorectal/phased-array coils for the staging and determination of the extent of cervical carcinoma. Twenty-two consecutive patients with biopsy-proven cervical carcinoma underwent MRI with integrated endorectal/phased-array coils before treatment. Magnetic resonance imaging was compared with clinical staging using surgical and pathological results as the gold standard. Eighteen of 22 patients underwent surgery. Seventeen of the 18 patients were correctly staged using an integrated endorectal/phased-array MRI with an overall staging accuracy of 94%. Fourteen of the 18 patients had a correct clinical staging with an overall staging accuracy of 78%. The overall accuracy of pelvic lymph node metastasis detection was 89% on MRI. These data showed that MRI using integrated endorectal/phased-array coils was more accurate than the clinical approach for the staging of cervical carcinoma. Magnetic resonance imaging using integrated endorectal/phased-array coils is a highly promising modality for detecting and staging cervical carcinomas.  相似文献   
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