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51.
OBJECTIVES: Our purpose was to determine whether there is adequate visibility and access for transvaginal oophorectomy in most patients and the success rate of the transvaginal approach. The final goal was to establish objective guidelines for choosing the route of oophorectomy with hysterectomy. STUDY DESIGN: Patients underwent laparoscopy-assisted vaginal hysterectomy (n = 91) or vaginal hysterectomy (n = 875). Ovarian removal, either unilateral (n = 97) or bilateral (n = 187), was carried out for clinical or prophylactic reasons. The accessibility of the ovaries for transvaginal removal was assessed by stretching the infundibulopelvic ligament and grading the position of the ovaries from 0 (no descent) to III (descent past the hymenal ring with traction). RESULTS: In 158 patients transvaginal bilateral oophorectomy was performed without laparoscopic assistance. In another 29 patients bilateral transvaginal oophorectomy was performed with laparoscopy-assisted vaginal hysterectomy, and prophylactic bilateral oophorectomy by the transvaginal route was successful in all but 1 of 143 patients with ovaries of grade I or higher. In 20 patients laparoscopic lysis of adhesions was necessary to permit transvaginal oophorectomy. Ninety-seven patients underwent transvaginal unilateral oophorectomy, 74 with conventional vaginal hysterectomy and 23 with laparoscopy-assisted vaginal hysterectomy. Among the patients not having oophorectomy, all ovaries had sufficient mobility to have been removed transvaginally. CONCLUSION: Good surgical practice dictates that visibility and accessibility be the primary criteria for selecting the route of oophorectomy with hysterectomy. In most patients the ovaries are visible and accessible to transvaginal removal. (Am J Obstet Gynecol 1996;175:1483-8.)  相似文献   
52.
The degeneration of the basal forebrain cholinergic system plays an important role in cognitive deterioration in aging and Alzheimer's disease. Brain cholinergic neurons and their projections are affected by changes in the circulating levels of estrogens, which exert their effects mainly through the estrogen receptors. In this study, we investigated the effect of aging, estrogen status and transgenic genotype on the number of cholinergic neurons and the estrogen receptor alpha (ERalpha) content in the medial septum-vertical limb of the diagonal band of Broca. We used 6- and 12-month-old female double transgenic mice carrying mutated human amyloid precursor protein (APPswe) and presenilin-1 (PS1-A246E), and their nontransgenic littermate controls, which had been sham-operated or ovariectomized at the age of 3 months. Brain sections were double immunostained for choline acetyltransferase (ChAT) and ERalpha and used for stereological cell counting. We found that the number of ChAT-immunoreactive (ir) neurons containing nuclear ERalpha-ir was significantly lower in 12- than in 6-month-old mice. However, the age of the mice, the transgenic genotype or ovariectomy had no effect on the total number of ChAT-ir neurons, or on the number and percentage of all ChAT-ir neurons that contained ERalpha. These results indicate that aging is associated with translocation of ERalphas from the nucleus to the cytoplasm. We propose that this phenomenon is linked to those age-related processes known to be involved in inhibiting ERalpha binding to nuclei.  相似文献   
53.
补肾宁心方对去卵巢兔动脉粥样硬化的保护作用   总被引:2,自引:0,他引:2       下载免费PDF全文
目的 研究补肾宁心方对去卵巢兔动脉粥样硬化形成的影响。方法 26只3月龄新西兰雌兔随机分为正常组、假手术组、对照组(卵巢切除)、中药组(卵巢切除并灌以补肾宁心方),除正常组外均于手术2周后给予高脂饮食,中药组同时灌胃给补肾宁心方中药,连续3个月。各组于第12周末测定血脂(TC、TG、LDL-C和HDL-C)以及一氧化氮(NO)水平;取主动脉行组织形态学观察以及在光镜和扫描电子显微镜下行病理学检查,利用图像分析仪计算动脉粥样硬化斑块内膜面积比和内膜中膜厚度比、面积比。结果 12周末除正常组外,各组动物血脂测定结果比较,差异无显著性。与对照组比较,中药组血清NO水平明显升高,主动脉硬化斑块面积与动脉内膜比值,内膜中膜厚度比、面积比均明显降低,主动脉病理变化减轻。结论 补肾宁心方可抑制去势雌兔动脉粥样硬化形成,对血管内皮细胞具有保护作用。  相似文献   
54.
This study investigated the effects of Seungnoidan (SND), which has been widely used as a remedy for cerebroneuronal diseases in Korean folk medicine, on the cerebrocortical adenosine triphosphate (ATP) and acetylcholine (ACh) contents in ovariectomized (OVX) rats. Female Sprague-Dawley rats were ovariectomized and maintained for 12 weeks to deplete ovarian steroid hormones, followed by oral administration of SND at 500 mg/kg/day for 14 weeks. SND markedly attenuated the high rate of body weight increase in OVX rats, and also reduced the decline of cerebral weight caused by ovariectomy (p < 0.05). Superfusion of SND at 50 mg/kg significantly increased the rate of cerebral blood fl ow, but did not change the mean arterial blood pressure. Deprivation of ovarian steroid hormones significantly decreased the cerebral ATP, choline and ACh contents, and these reductions were reduced by treatment of OVX rats with SND (p < 0.01). Additionally, SND also significantly elevated the cerebral choline acetyltransferase activities reduced by OVX (p < 0.01). Taken together, these results suggest that the pharmacological properties of SND may be implicated in the improvement of metabolic pathways of cerebral energy and cholinergic neurotransmitter function induced by deprivation of ovarian steroid hormones, and SND may be a promising herbal remedy for treatment of cerebral dysfunctions including dementia.  相似文献   
55.
To study the role of oestradiol and progesterone in the secretion of leptin, 21 normally ovulating women were recruited from those scheduled for ovariectomy plus hysterectomy performed in mid-follicular phase of the cycle. Seven of the women were used as controls and received no hormonal treatment post-operatively. Another seven women received oestradiol (oestradiol group) and the remaining seven women received oestradiol plus progesterone (oestradiol plus progesterone group). Serum leptin values showed a temporal but significant increase 24 h after the operation and were significantly correlated with the cortisol and progesterone values, which increased temporarily at 12 h. At that time a marked decline in oestradiol concentrations was seen. After the temporal increase, leptin values in the controls and the oestradiol group decreased significantly up to day 4 (P: < 0.05), while in the oestradiol plus progesterone group they increased (P: < 0.01) and were significantly higher than in the other two groups (P: < 0.05). Body mass index (BMI) was the most important variable accounting for the changes in leptin values post-operatively, but in the oestradiol plus progesterone group progesterone correlated significantly with leptin independently of BMI. These results suggest that progesterone and cortisol can stimulate leptin secretion in women regardless of oestradiol concentrations.  相似文献   
56.
目的 为确定雌激素可能具有的神经营养调节作用。方法 采用蛋白质印迹法检测上述指标的变化。结果 与卵巢未切除对照组相比 ,小鼠卵巢切除 10周后海马内脑源性神经营养因子 (BDNF)表达水平明显下降 ,给予 17β 雌二醇 (2 .4或 4 .8μg·d- 1,sc ,连续 12周 )替代具有明显的改善作用 (P <0 .0 1)。但卵巢切除及 17β 雌二醇替代对海马内神经营养因子 3表达水平无明显影响。结论 海马内BDNF表达水平的改变与雌激素缺乏具有密切关系。雌激素对调节海马内BDNF水平具有重要作用。  相似文献   
57.
Bone mineral density in mandibles of ovariectomized rabbits   总被引:2,自引:0,他引:2  
The purpose of this study was to evaluate the association between loss of ovarian function and bone mineral density changes in the mandibles of ovariectomized rabbits using peripheral quantitative computed tomography. Twenty-four adult female Japanese white rabbits were used in this experiment. The mandibular incisors were initially extracted to create implant bone. Twelve animals were bilaterally ovariectomized and the other twelve sham-ovariectomized 12 weeks after tooth extraction. All rabbits were sacrificed at 4 and 12 weeks after ovariectomy and sham-ovariectomy, with 6 rabbits in each of the four resultant groups. The edentulous parts of distal mandibular bodies were measured by peripheral quantitative computed tomography. There were significant decreases in total bone mineral density and trabecular bone mineral density in the mandibles of rabbits at 12 weeks post-ovariectomy. The results demonstrate the mineralized bone loss in the mandibles of ovariectomized rabbits.  相似文献   
58.
A single dose of dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD; 5 microg/kg, ip) inhibits 17beta-estradiol (E2)-induced uterine epithelial mitogenesis, apparently through disruption of stromal-epithelial interactions. To understand if TCDD alters early uterine (Ut) responses to E2, young adult C57BL/6J mice were ovariectomized and given (i.p.) either oil or 5 microg/kg TCDD. After 24 h, TCDD-treated mice received E2, and oil-treated mice were given E2 or oil. Body and Ut weights were collected 6 and 18 h later. Ut were flash-frozen at 6 h. E2 increased Ut weight (p < 0.0001) and Ut/body weight ratio (p < 0.0001), compared to mice given oil alone. Ut cyclin expression was assessed by an RNase protection assay. E2 increased mRNA expression for cyclin A2 and B1 (p < 0.05), in addition to D1, D2, and D3 (p < 0.001), while cyclin C was unchanged from oil controls and cyclins A1 and B2 were undetectable. In contrast, TCDD completely abolished E2-induced cyclin A2, which has been associated with S phase initiation, and reduced B1 and D2 (p < 0.05). Interestingly, TCDD did not alter E2-induced Ut weight increases at 6 h, but inhibited E2-induced Ut weight gain at 18 h. A 10-microg/kg TCDD dose was necessary for attenuation of the early E2-induced Ut weight increases (p < 0.01). Since TGF-beta regulates cyclins, Ut TGF-beta was also assessed in TCDD + E2-treated and control mice. TGF-beta mRNA levels were increased after TCDD compared to E2 alone (p < 0.01), suggesting a possible mechanism for TCDD inhibition of Ut cyclin A2. Thus, TCDD alters specific E2-regulated Ut G(1) phase activities and may inhibit E2-induced Ut epithelial mitogenesis by disrupting specific cell signaling mechanisms necessary for S phase initiation in vivo.  相似文献   
59.
卵巢切除对大鼠骨组织结构改变的影响   总被引:2,自引:0,他引:2  
目的:探讨卵巢切除对大鼠骨组织形态学改变的影响。方法:将18只3月龄雌性大鼠随机分为卵巢切除组及假手术组(对照组)。术后3周处死两组大鼠,获取股骨远端1/3处骨,分别进行石蜡包埋,塑料包埋切片及扫描电镜观察。结果:卵巢切除可引起大鼠骨小梁变细、中断,骨小梁表面钙盐沉积减少。结论:卵巢切除可使大鼠骨吸收增加,影响骨的稳定性,增加骨折发生的危险性。  相似文献   
60.
Objectives: In rabbits, ovariectomy has been shown to cause reduced blood flow to the bladder, increased free radical generation, and oxidative damage to the bladder. Thus, the antioxidant status of rabbits may play an important role in the damaging effects of ovariectomy. The present study analyzed total antioxidant content (TAC) in control, 14‐ and 28‐day ovariectomized (Ovx) female rabbit bladders using both ferric reducing ability of plasma (FRAP) and cupric ion reducing antioxidant capacity (CURPAC) assays. Methods: Twelve weight‐ and age‐matched virgin female New Zealand White rabbits (~ 4.0 kg) were separated into three groups of four rabbits each. Group 1 received ovariectomy surgery for 14 days. Group 2 received ovariectomy surgery for 28 days. Group 3 received sham operations. Results: FRAP did not show any significant differences between either muscle and mucosa or control and Ovx samples. CUPRAC revealed higher TAC in the control mucosa compared to muscle and significantly decreased antioxidant levels in 14‐ and 28‐day Ovx mucosal layers compared to the mucosa of the control rabbits. Conclusion: The CUPRAC method proved to be superior to the FRAP method for accuracy.  相似文献   
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