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1.
Summary In this work, we have studied the time-course of the effects of pharmacological administration of ovarian steroids on tyrosine hydroxylase (TH) activity in the limbic forebrain of ovariectomized rats. Administration of estradiol produced a late decrease in TH activity. This effect was found 24 hours after the last steroid injection, disappearing at 32 hours. It was antagonized by progesterone, since a single injection of this steroid to estradiol-pretreated rats reversed to control values the estradiol-induced decrease. Nevertheless, the administration of progesterone after estradiol treatment caused a short-time decrease in the limbic activity of TH, which was observed 4 hours after the last steroid injection, disappearing subsequently. On the other hand, the administration of progesterone alone produced a biphasic effect, with a reduction at 24 hours, followed by an increase at 32 hours. These effects were only observed in the animals non-treated with estradiol, disappearing with a previous treatment with estrogens. Hence, it can be concluded that both ovarian steroids may affect the limbic TH activity. Thus, estradiol produced a late inhibitory effect on the activity of this enzyme, which was antagonized by progesterone. Administration of the last one to estradiol-treated rats produced a short-time inhibitory effect, whereas its administration to non-treated rats produced a late biphasic effect (inhibition followed by stimulation), which was not observed in estradiol-treated rats.  相似文献   
2.
Females are disproportionately affected by constipation, which is often aggravated during pregnancy. Bowel function also changes during the luteal phase of the menstrual cycle. The aim was to compare the effects of acute administration of female sex steroids on gastric emptying, small bowel transit and colonic transit in healthy postmenopausal subjects. A second aim was to determine whether withdrawal of the hormones was associated with a change in transit. Forty-nine postmenopausal females were randomized to receive for 7 days 400 mg day(-1) micronized progesterone, 0.2 mg day(-1) oestradiol, combination of the two, or placebo. Treatment groups were balanced on age. Participants underwent whole gut transit measurement by scintigraphy using a 99m-labeled technetium-egg meal and 111-labeled indium-charcoal via a delayed-release capsule. Transit measurement was repeated after withdrawal of the study medications. The primary endpoints were ascending colon (AC) emptying half-life time (t1/2) and colonic geometric centre (GC) at 24 h. Secondary analysis variables were GC at 4 and 48 h, gastric emptying t1/2 and colonic filling at 6 h. There was a significant overall effect of progesterone on colonic transit with shorter AC emptying t1/2 and significantly greater colonic GC at 48 h. No transit endpoints were altered by oestradiol or combined hormonal treatment relative to placebo. Oestradiol and progesterone resulted in looser stool consistency. Withdrawal of the hormone supplement was not associated with significant alteration in transit. Micronized progesterone does not retard colonic transit in postmenopausal females.  相似文献   
3.
The in-vitro oestradiol (E2) and progesterone (P) production by corpora lutea (CL) obtained at sterilization from 30 untreated women and 43 women treated with norethisterone (NET) 300 micrograms daily was measured. The CL were obtained at different stages of the luteal phase in the untreated women [luteinizing hormone (LH) 0 to +3, n = 7; LH +4 to +7, n = 7; LH +8 to +11, n = 9; LH +12 to menses, n = 7] and on days LH +8 to +11 or cycle days 22 to 26 in the NET-treated women. In the treated women, four types of ovarian reaction were identified. Four women showed ovarian reaction Type A (completely inhibited ovarian activity), 14 women Type B (marked follicular activity, but no luteal function), 12 women Type C (normal follicular activity, followed by insufficient luteal function) and 13 women Type D (apparently normal follicular and luteal activity). The CL were incubated in Eagle's medium with and without stimulation by human chorionic gonadotrophin (HCG) for 2 and 4 h. In the untreated women, P and E2 production increased significantly with both incubation time and stimulation by HCG throughout the luteal phase, except in the late luteal phase (LH +12 to menses) where P increased (P less than 0.01) only after 4 h stimulation by HCG. The maximal production of P was found after 4 h incubation with HCG stimulation of CL tissue in the early-mid luteal phase (LH +4 to +7).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
5.
Autoimmune progesterone dermatitis is a rare condition, characterized by recurrent premenstrual exacerbations of a dermatosis, in which sensitivity to progesterone can be demonstrated. The sensitizing mechanism is unknown. The aim of this study was to test the hypothesis that cross-sensitivity between steroid groups could induce allergy to endogenous progesterone in these patients. 5 patients with autoimmune progesterone dermatitis and 1 with oestrogen-sensitive dermatitis have been patch tested with a corticosteroid series, conjugated oestrogen 1% in petrolatum (pet.), and 17-α-OH-progesterone 2% pet. There were no immediate or delayed reactions at 2 and 4 days to any steroid group. We have therefore been unable to demonstrate steroid cross-sensitivity, or a use for 17-α-OH-progesterone in the investigation of oestrogen - and progesterone-sensitive dermatoses.  相似文献   
6.
In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.  相似文献   
7.
The effects on endometrial morphology of a single, intramuscular dose of 100 mg of progesterone administered in the early luteal phase, between days LH + 1 and LH + 6, were studied in a group (n = 8) of normal, fertile subjects by morphometric techniques and transmission electron microscopy. While the dose of progesterone administered consistently resulted in an increase of salivary progesterone concentration to above the upper limit of the reference range, no significant effect on endometrial development was observed; in particular, endometrial development was not advanced.  相似文献   
8.
Aggressive angiomyxoma of the female pelvis and perineum: a case series   总被引:3,自引:0,他引:3  
Aggressive angiomyxoma (AA) was first described in 1983, and fewer than 150 cases have been reported in the world medical literature. These tumors are benign, locally infiltrative mesenchymal neoplasms with a predilection for the female pelvis and perineum and a tendency to recur. The size of AAs at presentation varies considerably; however, these tumors often achieve large dimensions before becoming clinically symptomatic. Surgical excision remains the mainstay of treatment, but whether clear, tumor-free surgical margins are necessary is controversial. We report a cohort of six patients treated surgically during the past 20 years for primary or recurrent AA. Treatment, surgical margin status, estrogen and progesterone receptor status, and outcomes are reviewed.  相似文献   
9.
目的 分析孕激素联合以铂类为主的常规化疗对卵巢上皮性癌1~4期患者的临床疗效。方法 以已行瘤体减灭术的卵巢上皮性癌患者1~4期为研究对象,分为单纯化疗组、己酸孕酮组和普维拉组。随访、统计各组各期患者的生存率及复发率、血清激素水平、骨密度变化以及化疗副反应。结果 孕激素联合以铂类为主的化疗对早期卵巢上皮性癌的预后无明显影响,但对晚期(3期)卵巢上皮性癌的术后近期以及远期(2~5年)生存率及复发率均有改善趋势。单纯化疗组、己酸孕酮组、普维拉组3期患者术后3年生存率分别为34.8%、66.2%、73.9%,复发率分别为72.2%、47.3%、40.6%;单纯化疗组、己酸孕酮组术后5年生存率分别为17.4%、48.4%,复发率分别为81.5%、62.4%。孕激素的使用不影响患者血清激素水平,也不增加化疗的毒、副作用。联合孕激素治疗的患者术后骨密度下降较一般绝经后妇女慢。结论 孕激素联合以铂类为主的常规化疗可改善晚期卵巢上皮性癌的预后,并且不增加化疗的毒副作用,可改善患者的骨量丢失。  相似文献   
10.
克罗米酚对血清雌激素和孕激素水平的影响   总被引:1,自引:0,他引:1  
目的探讨克罗米酚(CC)在诱发排卵过程中对雌、孕激素水平的影响。方法采用放射免疫法,测定16例不明原因不孕妇女在自然周期和用药周期的排卵前1天和排卵后10天血清雌二醇(E2)和孕酮(P)浓度。结果排卵前1天和排卵后10天,用药周期的E2、P浓度均高于自然周期(P<0.05)。结论克罗米酚在诱发排卵过程中可导致内源激素平衡紊乱。  相似文献   
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