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排序方式: 共有6037条查询结果,搜索用时 133 毫秒
51.
Norma A. Vavatsi Sophia A. Kouidou Paraschos N. Geleris Christos Tachmatzidis Theodoros Gikas Demetrios K. Tsifodimos Antonios C. Trakatellis 《Clinical genetics》1995,47(1):22-26
Restriction fragment length polymorphisms (RFLPs) at the apolipoprotein AI-CIII-AIV gene cluster and their association with coronary artery disease (CAD) and lipid levels were studied in a Northern Greek population. Ninety-five patients with CAD and fifty-four normal controls, angio-graphically proven, were included in this study. Using genomic hybridization techniques, three polymorphic restriction sites were identified at this locus: the PstI at the 3' end of the apoAI gene, the SacI at the 3' non-coding region of the apoCIII gene and the PvuII at the intergenic region between the apoCIII-AIV genes. The rare allele (P2) arising from the absence of the PstI restriction site was observed with a significantly higher frequency (p<0.01) in patients compared to normals (0.11 vs 0.02). In contrast, the rare allele for the SacI polymorphic site had a similar distribution among patients and controls (0.12 vs 0.16). The same was observed for the PvuII RFLP (0.04 vs 0.05). Correlation of lipid and apolipoprotein AI levels with the three RFLPs revealed no significant association, although apo AI and HDL were lower in patients with the P2 allele. Thus, in this Greek population, only the PstI polymorphism, among the polymorphic restriction sites examined, appears to be associated with CAD. 相似文献
52.
The effects of intracerebral implants of steroid hormones on scent marking in the female gerbil (Meriones unguiculatus) were studied in two experiments. In Experiment 1 various steroids were implanted alone or in combination into the preoptic and anterior hypothalamic area of ovariectomized females. Unilateral implants of testosterone + estrogen, estrogen, estrogen + progesterone, testosterone and testosterone + progesterone stimulated a significant level of marking when compared to controls. Experiment 2 utilized bilateral implants of estrogen dissolved in paraffin in order to explore the distribution hormone sensitive areas in the brain which might be important in the regulation of scent marking in the female gerbil. Pellets of estrogen-paraffin were implanted stereotaxically into either the anterior hypothalamus, preoptic area, septum, hippocampus, thalamus, amygdala or anterior olfactory nucleus of ovariectomized females. Total dosage of hormone implanted was 8.2–8.4 μg. A significant level of marking resulted in animals receiving implants into the anterior hypothalamus, preoptic area and septum when compared to controls. Marking appeared at about the same rate in each of these groups; however, the level of marking attained differed. By the last trial, anterior hypothalamic implanted animals were marking significantly more often than animals in either the preoptic or septum groups. Although there was no evidence of ieakage from the brain, the data suggested that some rapid diffusion of hormone, largely restricted to the brain, was taking place or that the three areas were differentially responsive to the hormone. The data do indicate that some localization of function does exist with respect to regulation of scent marking in the female. 相似文献
53.
Marius J. van der Mooren Antonius G. J. M. Hanselaar George F. Borm Rune Rolland 《Maturitas》1994,20(2-3):175-180
Objective: To describe changes in the withdrawal bleeding pattern and endometrial histology during a sequential 17β-estradiol —dydrogesterone regimen in postmenopausal women. Design: Open-label, non-comparative, prospective study. Setting: Gynecological outpatient department of a university hospital. Patients: Twenty-seven healthy nonhysterectomized postmenopausal women. Interventions: Continuous micronized 17β-estradiol supplementation, 2 mg daily, and cyclic administration of dydrogesterone, 10 mg daily for the first half of each 28 day treatment cycle. Main Outcome Measures: Changes in the characteristics of the withdrawal bleeding pattern and the endometrial biopsy histology during 2 years of treatment. Results: The initial withdrawal bleeding was comparable to normal menstruation with respect to amount and duration. During the 2 years of treatment the bleeding showed a significant tendency to become shorter with less blood loss. This was mainly the result of the decrease (P < 0.001) in the number of days per cycle with bleeding grade II (normal menstruation). None of the women developed endometrial hyperplasia, and in almost all women the given hormone replacement therapy regimen induced secretory or atrophic changes of the endometrium. Conclusions: This sequential 17β-estradiol —dydrogesterone regimen can be regarded as safe with respect to the prevention of endometrial disease and appeared to foster patient compliance. 相似文献
54.
Summary We analyzed the results of clinical studies on the therapeutic efficacy of hormone monotherapy with tamoxifen, medroxyprogesterone acetate, and aminoglutethimide in metastatic breast cancer, which were published between 1971 and 1986 and involved altogether 7000 patients. The overall response rates in patients treated with these hormonal single agents at various dose levels ranged from 31%–42%. When only estrogen receptor-positive patients were considered, the response rates lay between 41% and 54% in groups which were treated with the antiestrogenic agents tamoxifen or aminoglutethimide. The duration of remission was 12 months for tamoxifen- and aminoglutethimide-treated women, whereas medroxy-progesterone acetate effected remissions lasting from 6–16 months. The overall mean survival from start of therapy in tamoxifen- and aminoglutethimide-treated groups was 20 months, whereas information concerning this therapeutic parameter was available only in a minority of medroxyprogesterone acetate-treated groups. With respect to the response by site of metastatic lesions, all three agents caused a significantly higher degree of remissions in the soft tissue as compared to visceral disease.Abbreviations AG
Aminoglutethimide
- MPA
Medroxyprogesterone acetate
- TAM
Tamoxifen 相似文献
55.
Camil Castelo-Branco Montserrat Rovira Francesca Pons Magdalena Durán Jordi Sierra Angels Vives Juan Balasch Albert Fortuny Juan Vanrell 《Maturitas》1996,23(3):307-312
Long permanent remissions in malignant hematopoietic disorders can often be achieved by autologous bone marrow transplantation (ABMT) or by allogenic bone marrow transplantation (BMT). Previous studies have shown that such therapies may induce osteoporosis due to iatrogenic ovarian failure. The administration of hormone replacement therapy (HRT) in these women could prevent the adverse effects of long-term ovarian failure without remarkable side effects. The aim of this study was to evaluate how the bone mass is affected by HRT in patients undergoing ABMT or BMT adjusting the results for age, weight, and height. Subjects and methods: Thirteen women with previous ABMT/BMT were treated with a standard dose (0.625 mg/day) of conjugated equine estrogen (CEE) or with 50 μg/day of 17-β-estradiol in transdermal therapeutic systems (TTS) plus 5 mg/day of medroxyprogesterone acetate sequentially added to the last 12 days of estrogen therapy. Bone mass was measured prior to and 12 months following HRT. Blood samples were collected before therapy and during the 6th and 12th treatment months. Results: The mean time elapsed between bone transplantation and HRT initiation was 13.0 months (range 3–26 months). Before treatment nine patients were osteopenic and after HRT bone mass increased in all cases. Following ABMT/BMT, hepatic hyperenzymemia was detected in three patients. After 6 and 12 months of treatment no significant changes were observed in hepatic enzymes. Conclusion: Although hepatic hyperenzymemia is commonly considered as a contraindication for HRT, our results suggest that HRT is safe for these patients and that such therapy should be initiated after transplantation in women to prevent adverse effects of long-term ovarian failure. 相似文献
56.
Immune response of adults to sequential influenza vaccination 总被引:1,自引:0,他引:1
Annual immunization against influenza is recommended for numerous individuals, but the antibody response to sequential vaccination has not been well characterized. Levels of hemagglutination-inhibition antibody were measured in adults given either two or three doses of trivalent influenza vaccine at six-month intervals. A significant rise in the number of individuals with antibody titers of greater than or equal to 40 was seen for all three antigens only after initial vaccination. Repeated vaccination was necessary to maintain adequate antibody levels only to the A/Brazil (H1N1) antigen; it did not significantly affect the proportions of individuals with protective levels of antibody to either the A/Bangkok (H3N2) or the B/Singapore 222/79 antigens. These findings do not support the current recommendation for annual immunization when the vaccine formulation has not changed. 相似文献
57.
Mechanisms of peptide YY release induced by an intraduodenal meal in rats: neural regulation by proximal gut 总被引:5,自引:0,他引:5
Fu-Cheng Xiaomei Anini Younes Chariot Jacques Castex Nathalie Galmiche Jean-Paul Rozé C. 《Pflügers Archiv : European journal of physiology》1997,433(5):571-579
Peptide YY (PYY) release in anaesthetized rats was studied during the 2 h following the intraduodenal administration of a
semi-liquid meal of 21 kJ. Surgical and pharmacological manipulations were performed in order to analyse the mechanisms of
PYY release. Postprandial PYY release was suppressed or strongly decreased by caecocolonectomy, truncal vagotomy, tetrodotoxin,
hexamethonium, sensory denervation by perivagal capsaicin, and by the NO-synthase inhibitor L-N-arginine methyl ester, while atropine, adrenergic blockers, antagonists of type-A or type-B cholecystokinin (CCK) receptors
or bombesin receptors had no effect. Comparing the digestive transit of the semi-liquid meal with the amount of PYY contained
in the small bowel wall showed that nutrients had not reached the area rich in cells containing PYY by 30 min, the time at
which there was a large PYY release in plasma. By 120 min, the meal front had travelled 72% of the small intestine length,
just beginning to reach the PYY-rich part of the ileum. We conclude that the main postprandial PYY release studied in this
model comes from ileal and colonic L-cells indirectly stimulated through a neural mechanism originating in the proximal gut
and involving sensory vagal fibres, nicotinic synapses and NO release, while CCK and bombesin do not seem to be physiologically
involved.
Received: 17 July 1996 / Received after revision: 11 October 1996 / Accepted: 18 October 1996 相似文献
58.
Objectives:To analyse the relationship between nocturia, age, the menopausal transition, parturition and hormone replacement treatment (HRT) in women.Material and methods:A questionnaire study was carried out in 3669 randomly selected women (out of 6000 invited) in the County of Jämtland, Sweden. Questions were asked about health, the occurrence of somatic diseases and symptoms, habits, health care and medication.Results:In univariate analyses age, menopausal state and HRT, but not parturition, were associated with increased nocturia. In a multiple logistic regression analysis, independent correlates for two or more nocturnal micturition episodes versus no more than one episode were: health, poor versus good 2.9 (2.1–3.8); <5 years after the menopause versus before 1.8 (1.3–2.5); 5–9 years after the menopause versus before 2.1 (1.5–3.0); ≥10 years after the menopause versus before 3.1 (2.3–4.2). Age and HRT were deleted by the logistic regression model.Conclusion:The present data indicate that menopausal state, but not age, parturition and HRT are independent correlates of nocturia in 40–64-year-old women. 相似文献
59.
60.
De Coster R. Caers I. Haelterman C. Debroye M. 《European journal of clinical pharmacology》1985,29(4):489-493
Summary The effect of a single oral dose of 400 mg ketoconazole, given as an 80 mg/ml suspension, on total and physiologically free (i.e. non-sex hormonebound) testosterone and 17-oestradiol has been investigated in 6 healthy male volunteers. The two steroids fell to nadir levels of 18 and 60% of their respective initial concentrations 6 hours after drug intake, and then completely recovered. Although in vitro slight displacement of testosterone from the sex-hormone binding globulin, by high doses of ketoconazole was found, the physiologically free concentration of testosterone in vivo was closely correlated with that of the total hormone, suggesting that there is no direct interference with sex-hormone binding globulin in vivo. Plasma LH and FSH were not significantly modified by treatment. The effect of ketoconazole on plasma oestradiol levels was less pronounced and was not clearly related to a block of the aromatase system, as reported in vitro.This work was presented in part at the International Symposium on the Regulation of Androgen Actions, Montreal, 29th June–1st July 1984 相似文献