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31.
Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports. While at week 5 of gestation inhibin-A, activin-A and follistatin concentrations were similar to those at the follicular phase, all three increased progressively (P < 0.001) to maximal concentrations in week 36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately 22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/- 418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174 pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was undetectable (<12 pg/ml) between week 5-16 of gestation but increased slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was undetectable throughout pregnancy. Post-partum concentrations of inhibin-A (41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml), pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were substantially lower than at week 36 of gestation. The activin-A:follistatin ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more free activin-A is available in the maternal circulation during late pregnancy.   相似文献   
32.
Pathophysiology of mild endometriosis: review of literature   总被引:2,自引:0,他引:2  
Endometriosis is a puzzling condition and the literature ischaracterized by a large number of uncontrolled reports on itsaetiology and pathophysiology. In particular the relationshipbetween mild endometriosis and subfecundity is uncertain. Thispaper critically reviews the published literature on the pathogenesis,prevalence, menstrual symptomatology and natural history ofendometriosis. Furthermore, factors implicated in causing subfecundityin relation to endometriosis and the impact of various treatmentsin enhancing fertility among women with mild endometriosis havebeen assessed.  相似文献   
33.
Hepatic stellate cells (HSC) become activated in liver injury, proliferating and secreting components of connective tissue. Activated HSC lose their native retinol and fat storing capacity. Signals from hepatocytes and/or Kupffer cells injured (eg, by iron overload) may contribute to the so-called activated HSC phenotype. Primary rat HSC cultures were treated with retinol to determine if this could produce a quiescent cell for controlled in vitro studies of activation. Retinol resulted in suppressed DNA synthesis in proliferating HSC, a reorganization of actin filaments, and a return of fat storage. However, it did not suppress the expression of fibrogenic genes such as those for collagens type I and IV, and TGF-beta1. Furthermore, retinol-treated cells may increase expression of these genes in response to conditioned medium from hepatocyte cultures. The effect is especially apparent for collagen type I mRNA, and with conditioned medium from iron-loaded hepatocytes. Thus, retinol may be a two-edged sword in iron overload, potentially suppressing HSC proliferation on the one hand, and sensitizing a fibrogenic pattern of gene expression on the other. Factors influencing this balance merit further study.  相似文献   
34.
Although the conventional method of pain relief during outpatient oocyte recovery involves physician-administered drugs, patient- controlled analgesia (PCA) offers an alternative technique with the potential to give women more control over peroperative analgesia. We conducted a prospective randomized study to compare the effect of fentanyl administered either through a PCA delivery system or by a physician. Thirty-nine women were randomized to PCA during egg collection while 42 were allocated to receive intermittent doses administered by a physician. Pain was evaluated by means of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P = 0.1). In the PCA group, 64% of women felt very satisfied with their analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the PCA users, 39% of demands were successful. Significantly more fentanyl (97.5 microg) was used in the PCA group than in the other group (84.6 microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective alternative to physician-administered techniques, many women still feel the need for more analgesia during the procedure.   相似文献   
35.
Thirty-four women requesting laparoscopic sterilization underwenta fixed schedule regimen for multiple follicular developmentwhich included norethisterone and clomiphene citrate. Follicleaspiration for oocyte recovery was attempted laparoscopically34 h after administration of 5000 IU human chononic gonadotrophin(HCG). Nineteen women were given 80 mg tamoxifen orally 4 hprior to HCG injection, while 15 acted as controls. There wasno statistical difference in fertilization rates in vitro betweentamoxifen-treated patients and controls (80 and 68% respectively).In addition, the morphological characteristics of the oocytes,the rates of cleavage, and the concentrations of oestradiol,progesterone and androstenedione in follicular fluid were similarin the two groups. Tamoxifen was detected in substantial amountsin follicular fluids of patients given tamoxifen. These resultssuggest that high-dose tamoxifeii, in clinically used doses,does not adversely affect the final stages of maturation orthe fertilization and early cleavage of human oocytes.  相似文献   
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To provide a high level of orthopaedic trauma care, education and research, across the country, trauma services in the UK require modification. Good information is necessary prior to formulating ideas and proposals. Trauma care provision must be considered comprehensively at both the national and local levels. As a first step, it is important to know just how many acute hospitals there are in the country. It is also important to know about the distribution of surgical specialities and the number of consultant orthopaedic surgeons staffing those hospitals.  相似文献   
39.
AIM: To provide a simple method for assessing centile change based on the British 1990 growth reference. STATISTICAL METHOD: The change in SD score over a period of time has SD square root of 2(1-r), where r is the correlation between the first and second SD score. This leads to an SD score for centile change. DATA: Annual height measurements from 2 to 9 years for 318 children from the French longitudinal growth study. RESULTS: The correlations between heights at different ages are higher for shorter measurement intervals and at older ages. The chance of a child's height centile falling one centile band width is correspondingly smaller for shorter measurement intervals and at older ages. An increase in height measurement error reduces the correlations and dramatically increases the chances of centile crossing. CONCLUSIONS: Quantitative height monitoring based on centile change is provided for whole year periods between 2 and 9 years of age. Effective monitoring requires the measurement error to be as small as possible.  相似文献   
40.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
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