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去势抵抗性前列腺癌治疗进展   总被引:9,自引:8,他引:1  
大部分前列腺癌经过治疗终将进展为临床难治的去势抵抗性前列腺癌,目前的治疗手段均难以提高其2~3年的生存期。近年来通过不同作用机制治疗去势抵抗性前列腺癌的许多新型有效的药物投入临床或进入临床试验。本文就这方面的研究进展作一综述。  相似文献   
25.
目的 探讨合理情绪疗法(RET)对子宫切除患者焦虑、抑郁心理的运用及效果.方法 在临床中运用RET理论对32例符合入组条件的子宫切除患者的焦虑、抑郁心理进行心理干预.结果 32例患者的焦虑、抑郁心理明显改善,情绪相应好转.结论 合理情绪疗法可以转变患者的认知,树立正确信念,缓解焦虑症状,增强战胜疾病的信心,使其在最佳心理状态下接受治疗和护理,达到早日康复的目的.  相似文献   
26.
Many of the effects of gonadal steroid hormones in the male brain are due to the actions of the testosterone metabolite estradiol, which is synthesized by the actions of the P450 enzyme aromatase. Aromatase activity is present in regions of the preoptic area, hypothalamus, and limbic system. Levels of aromatase activity in the brain are highly dependent on gonadal steroid hormones in many brain regions, but not all. We examined the distribution of aromatase mRNA in adult male and female rat brains as well as the regulation of the levels of aromatase mRNA in the brains of males by gonadal steroid hormones using in situ hybridization. This method was performed using a 35S-labelled cRNA probe, transcribed in vitro from the rat ovarian aromatase cDNA. In the adult male, many heavily labelled cells were found in the encapsulated bed nucleus of the stria terminalis (BNST), the medial preoptic nucleus (MPN), the ventromedial nucleus (VMN), the medial amygdala (mAMY), and the cortical amygdala (CoAMY). The regional distribution of aromatase mRNA was similar in females, but females tended to have a lower number of aromatase mRNA expressing cells in each region compared to males. Aromatase mRNA levels in the BNST, MPN, VMN, and mAMY tended to be lower in castrated males than in intact males, whereas aromatase mRNA levels were unaltered by castration in the CoAMY. The degree of reduction in mean levels of aromatase mRNA following castration does not simply account for the large changes measured in activity following castration. Examination of the entire population of individual cells expressing aromatase mRNA in castrated males suggests that aromatase mRNA may be regulated by steroid hormones differentially in specific populations of neurons within regions where activity is known to decrease following castration. © 1996 Wiley-Liss, Inc.  相似文献   
27.
The effects of various means of interfering with androgen action on rat coagulating gland, ventral prostate, lateral type 1 prostate, lateral type 2 prostate, and dorsal prostate were examined morphologically and quantitatively by assessing DNA content, wet weight, protein content, and zinc concentrations. Adult male Sprague-Dawley rats were subjected to 2 weeks of interfering with androgen action by treatment with Leuprolelin (a luteinizing hormone-releasing hormone analog), Finasteride (a 5α-reductase inhibitor), or diethylstilbestrol (DES), or by physical castration. For all prostatic lobes, inhibition of 5α-reductase elicited the smallest reduction in prostatic wet weight, DNA and protein contents, and zinc concentration. The most profound reductions in all parameters were elicited by castration. Treatments with DES and Leuprolelin gave intermediate effects with DES being the more effective in reducing all parameters in all prostatic lobes. Morphological changes elicited by all forms of androgen blockade were reduction of epithelial height, relative increase of connective tissue, reduction in ductal diameter, length, and number. The order of effectiveness of the various treatments on morphological features was as described above. While all forms of androgen blockade elicited similar effects throughout the prostate, differences in response to all forms of interference with androgen action were observed in different lobes of the prostate with regard to wet weight, DNA and protein contents, and zinc concentration as well as morphological effects. Regressive changes at the morphological level were particularly striking in the coagulating gland and ventral prostate, and indistinct in the lateral type 2 prostate. Prostatic zinc concentration in both normal and androgen-deprived rats was the highest in the lateral type 2 prostate and was reduced by interfering with androgen action to the greatest extent in the dorsolateral prostate (lateral type 1 and type 2, and dorsal prostate). The distribution of zinc correlated with the expression of metallothionein, which was detected by immunocytochemistry only in the lateral type 2 prostate of both normal and androgen-deprived rats. Intraprostatic heterogeneity of zinc and metallothionein expression emphasizes interlobar differences in biological function within the rat prostate. The mechanism of development of regional heterogeneity within the prostate may shed light on the pathogenesis of prostatic proliferative diseases (prostatic hyperplasia and prostatic cancer) that initially owe their development to focal changes within large cell populations. © 1996 Wiley-Liss, Inc.  相似文献   
28.
Objective.— In this study, we evaluated the influence of sex and estrogen treatment on nitroglycerin (NTG)‐induced neuronal activation in the rat brain. Background.— Systemic NTG activates cerebral nuclei of rat involved in nociceptive transmission, as well as in neuroendocrine and autonomic functions. These changes are considered relevant for migraine, since NTG consistently induces spontaneous‐like attacks in migraineurs. Methods.— Intact and castrated male and female rats, and castrated female rats treated with estradiol benzoate (or placebo) were injected with NTG and sacrificed after 4 hours. Rats were perfused, and their brains were processed for Fos protein, a marker of neuronal activation. Results.— Data showed a reduced expression of NTG‐induced Fos protein in the paraventricular nucleus (PVH), supraoptic nucleus (SON), and nucleus trigeminalis caudalis (SPVC) of male rats in comparison with female rats. Furthermore, in castrated female rats, NTG‐induced neuronal activation was reduced in PVH, SON, central nucleus of the amygdala (AMI), nucleus tractus solitarius (NTS), area postrema (AP), and SPVC, while in castrated male rats Fos expression was reduced uniquely in the SPVC. Chronic administration of estrogens restored Fos protein expression in PVH, SON, AMI, NTS, AP, and SPVC in castrated female rats. Conclusion.— These data provide a support for the existence of a sexual dimorphism in NTG‐induced neuronal activation, and they prompt a specific model for evaluating and modulating the influence of estrogens upon the cerebral structures implicated in the pathophysiology of migraine.  相似文献   
29.
雄激素对快速老化小鼠海马神经元凋亡及超微结构的影响   总被引:2,自引:0,他引:2  
目的:探讨雄激素对快速老化小鼠海马神经元凋亡及超微结构的影响.方法:7月龄雄性快速老化小鼠(SAMP8)随机分为假手术对照组、去势组及去势 雄激素补允治疗组.十一酸睾酮(TU)剂量为37.4 mg·kg-1·15 d-1.雄激素补充治疗45 d后,通过Nissl染色观察海马神经元数量和形态的变化;TUNEL法检测细胞凋亡;流式细胞仪检测细胞的凋亡率;透射电镜观察超微结构的改变.结果:去势组海马神经元数量明显减少,凋亡数量和凋亡率显著增加,超微结构病理变化严重.雄激素补充治疗后,观察结果与假手术对照组相比无统计学意义.结论:去势后雄激素缺乏可导致海马神经元异常凋亡增加,数目减少,结构受损.雄激素补充治疗可减轻神经元损伤,这可能是其改善SAMP8小鼠学习记忆功能作用机制之一.  相似文献   
30.
Outcomes of alternative (second‐line) antiandrogen therapy in 112 patients with relapsing prostate cancer after first‐line hormonal therapy were analyzed. A good response (prostate‐specific antigen [PSA] decrease ≥50%) and a partial response (PSA decrease of 0–50%) by switching from bicalutamide (BCL) to flutamide (FLT) and from FLT to BCL were achieved in 35.4% (28/79) and 30.4% (24/79), and in 45.0% (9/20) and 20.0% (4/20) of cases, respectively. A good response and a partial response with the change from chlormadinone acetate (CMA) to a non‐steroidal antiandrogen (FLT or BCL) and from a non‐steroidal antiandrogen to CMA were obtained in 25.0% (2/8) and 37.5% (3/8), and in 20.0% (1/5) and 0% (0/5) of cases, respectively. In multivariate analyses, a second‐line good response was significantly predictive of cause‐specific survival from first therapy relapse to cancer death in all patients. Patients (52/112, 46.4%) with ≥30% decrease in PSA levels were associated with significantly better cause‐specific survival as measured from the start of first‐line treatment and first‐line relapse.  相似文献   
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