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31.
OBJECTIVES: Previous studies indicate that low-dose hormone replacement therapy (LD-HRT) can relieve vasomotor symptoms and prevent spine bone loss. METHODS: In the present study, we evaluated the effects of a low dose of conjugated equine estrogens (CEE; 0.3 mg) associated with different progestins in continuous combined scheme [2.5 mg of medroxyprogesterone acetate (n=25), 5 mg dydrogesterone (n=27), 2.5 mg nomegestrol (n=11)] as single group, on femur bone mineral density (BMD) and bone metabolism in young postmenopausal women (相似文献   
32.
Polycystic ovary syndrome (PCOS) is a common endocrine condition that affects fertility through oligo-ovulation, hyperandrogenism and polycystic morphology of the ovaries. Since it has been demonstrated a high incidence of insulin resistance in PCOS patients, our study aimed to evaluate the efficacy of the integrative treatment with D-chiro-inositol (DCI) (500?mg die, per os, for 12 weeks) on hormonal parameters and insulin sensitivity in a group of overweight/obese PCOS patients (body mass index; BMI?>?26). After the treatment, interval several endocrine parameters improved (luteinizing hormone [LH], LH/follicle stimulating hormone [FSH], androstenedione and insulin), insulin response to oral glucose tolerance test reported the significant improvement of insulin sensitivity as well as the gonadotropin-releasing hormone (GnRH)-induced (10?µg, in bolus) LH response. BMI decreased, though no lifestyle modification was requested. When data were analyzed according to the presence or absence of first-grade diabetic relatives, PCOS patients with diabetic relatives showed greater improvement after DCI administration. In conclusion DCI administration is effective in restoring better insulin sensitivity and an improved hormonal pattern in obese hyperinsulinemic PCOS patients, in particular, in hyperinsulinemic PCOS patients who have diabetic relatives.  相似文献   
33.
OBJECTIVES: an increasing interest is being focused on the role of the somatotropic axis in the modulation of body weight and fat distribution, particularly in climacteric women. The influence of the glycometabolic state on the somatotropic axis in postmenopausal and in obese subjects has not been investigated. The aim of the present study is to evaluate whether menopause and body mass index (BMI) affect the response of growth hormone (GH), insulin-like growth factor-binding protein-1 (IGFBP-1) and -3 (IGFBP-3) to the oral glucose tolerance test (OGTT). METHODS: the study included 24 women, aged 45-55 years, categorized into 4 groups, premenopausal pre-obese (BMI = 28.5 +/- 0.8 Kg/m2) and normal body weight (BMI = 22.2 +/-1.1 Kg/m2), and postmenopausal pre-obese and normal body weight. All women underwent: (1) a biophysical evaluation with determination of waist/hip ratio; (2) an assessment of fat and lean tissue mass and body fat distribution by total body DEXA; and to (3) an OGTT. RESULTS: in response to OGTT plasma GH levels significantly decreased in all groups, but the relative decrease was more prominent in the lean subjects. A significant decrease of IGFBP-1 levels in response to OGTT was observed in all women, regardless of menopausal age and BMI, while IGFBP-3 levels did not significantly change in either group. CONCLUSIONS: in conclusion, the impact of both BMI and menopausal condition on GH, IGFBP-1, and -3 response to OGTT is limited to a blunted GH response in overweight women compared with normally-weighing ones. These findings appear to rule out the hypothesis that a common glycometabolic derangement may affect both the modifications of body weight and of the somatotropic axis observed in perimenopausal women.  相似文献   
34.
Ectopic ureter and ureterocele: their varied sonographic manifestations   总被引:1,自引:0,他引:1  
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography.  相似文献   
35.
Gay  JC; Beckman  JK; Brash  AR; Oates  JA; Lukens  JN 《Blood》1984,64(4):780-785
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci.  相似文献   
36.
37.
To define the role of noradrenergic regulation of growth hormone (GH) secretion in a primate species, spontaneous and GH-releasing hormone (GHRH) stimulated GH secretion was studied in 6 chronically catheterized adult male cynomolgus monkeys before and after inhibition of norepinephrine synthesis. Blood samples were obtained at 15-min intervals during an 8-hour period to characterize the pattern of GH secretion, and the GH response to GHRH, 10 micrograms/kg i.v., was determined. These measurements were repeated 2 weeks later, 2 h after the intravenous administration of 12.5 mg/kg of the dopamine-beta-hydroxylase inhibitor diethyldithiocarbamate (DDTC), which has been shown to be an effective norepinephrine synthesis inhibitor in the rat. Spontaneous and stimulated GH secretory patterns before and after DDTC administration were compared. Both the frequency and the amplitude of spontaneous GH pulses were markedly reduced by DDTC [3.8 +/- 0.4 before vs. 1.8 +/- 0.4 peaks/8 h after DDTC (p less than 0.005) and 5.5 +/- 0.7 vs. 2.0 +/- 0.6 ng/ml (p less than 0.01)]. Areas under the curve were also reduced by DDTC treatment [10.8 +/- 1.0 vs. 5.7 +/- 1.1 ng.h/ml (p less than 0.01)], and DDTC administration diminished the peak GH responses to GHRH [12 +/- 6 vs. 4 +/- 2 ng/ml (p less than 0.05)]. These results are consistent with the belief that DDTC is a potent inhibitor of spontaneous and GHRH-induced GH secretion. The action of DDTC could be mediated by a reduction in GHRH due to reduced norepinephrine synthesis, by an increase in somatostatin release through a dopaminergic stimulus, or by a direct dopaminergic effect on somatotrophs.  相似文献   
38.
Background Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis with frequent clinical presentation as erythroderma. Conventional systemic treatment is often unsatisfactory and limited by long‐term toxicity. The use of tumour necrosis factor (TNF) antagonists has been reported previously in single cases, but lacking long‐term follow‐up or comparison between different biological agents. Objectives To assess the long‐term efficacy and safety of TNF‐alpha antagonist, infliximab and etanercept, either in monotherapy or in combination therapy of severe, refractory adult‐onset PRP. Methods Seven patients of adult‐onset PRP, six newly diagnosed type‐I and 1 type‐II, which were resistant or ineligible to conventional systemic treatment, received a single course of infliximab or etanercept therapy, alone or in combination with low‐dose acitretin (>0.25 mg/kg/daily). After complete remission and treatment discontinuation, a follow‐up period of 12 months was evaluated for relapses. Results Six patients obtained complete remission after a single course of anti‐TNF‐alpha therapy: mean therapy duration was 19.3 weeks (range 6–48 weeks). All patients obtained significant clearing (>75% of body surface area) of skin lesions at week 12. Two patients with marked keratoderma developed localized disease recurrence during treatment. During follow‐up, only a single patient, affected by type II PRP, had disease relapse. Conclusions Both TNF‐alpha antagonists proved successful for the treatment of refractory, adult‐onset PRP, yielding complete and persistent clinical responses in type‐I PRP. Infliximab was associated with a more rapid onset of action, while treatment duration was comparable with etanercept. PRP type II warranted long‐term therapy and showed relapse after drug discontinuation.  相似文献   
39.
Raloxifene is a selective estrogen modulator able to exert an estrogen-like action on some target tissues and a specific antiestrogenic action on the uterus and breast. In ovariectomized rats ,it has been shown to stimulate the β-endorphin and allopregnanolone concentrations of the anterior and neurointermediate pituitary lobes ,the hypothalamus and the hippocampus. The present study aimed to evaluate, in 12 healthy postmenopausal women ,the effect of 60 mg/day raloxifene hydrochloride administration for 6 months on plasma β-endorphin and allopregnanolone levels ,and on the dynamic changes of both β-endorphin and allopregnanolone secretion after the administration of: (1) clonidine ,an α2-presynaptic adrenergic agonist; (2) naloxone ,an opioid receptor antagonist; and (3) fluoxetine, a serotonin selective reuptake inhibitor. The administration of raloxifene significantly increased both circulating β-endorphin and allopregnanolone concentrations ,at both the third and sixth months of treatment (p < 0.01). Clonidine ,fluoxetine and naloxone administration before therapy was not able to stimulate the release of β-endorphin ,but the response was completely restored after raloxifene administration. Before therapy ,clonidine and naloxone tests were accompanied by a significant rise in allopregnanolone secretion; the same changes were observed after raloxifene administration, but with significantly higher allopregnanolone concentrations at each time considered. While the fluoxetine test before therapy failed to increase the release of allopregnanolone ,the same test after 6 months of raloxifene administration was characterized by a significant release of allopregnanolone at 60 and 90 minutes. The present data indicate that raloxifene has an estrogen-like effect on neuroendocrine pathways in postmenopausal women.  相似文献   
40.
There is strong epidemiological, experimental and clinical evidence that the etiology of breast cancer is closely related to long-term exposure of breast epithelium to sex steroid hormones. Estrogens can enhance the development of breast cancer by stimulating cell proliferation rate and thereby increasing the number of errors occurring during DNA replication, as well as by causing DNAdamage via their genotoxic metabolites produced during oxidation reactions. Anti-estrogenic drugs, including tamoxifen, raloxifene and anastrozole, have been tested with promising results in the chemoprevention of breast cancer in high-risk women. As for the use of exogenous sex-steroids in the gynecological practice, data about breast cancer risk associated with oral contraception are reassuring, and available data on oral hormone replacement therapy (HRT) use for not more than 5 years have failed to detect a significant increase in the risk of developing a breast cancer. Long-term HRT administration increases the incidence of this tumor slightly, with a relative risk ranging from 1 to 2 depending on hormone preparation. Estrogens alone, even if taken for long periods of time, seem to be safer than estrogen/progestin combinations. New administration routes and novel hormone regimens are currently under evaluation,.and these new HRT modalities could have different impact on breast cancer risk because of their metabolic and pharmacodynamic effects.  相似文献   
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