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排序方式: 共有1309条查询结果,搜索用时 15 毫秒
101.
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103.
McTavish KJ Jimenez M Walters KA Spaliviero J Groome NP Themmen AP Visser JA Handelsman DJ Allan CM 《Endocrinology》2007,148(9):4432-4439
Rising serum FSH levels is one of the earliest signs of human female reproductive aging. Whether or not elevated FSH remains a passive reflection of a diminishing ovarian follicle pool or actively contributes to declining female fertility with age has not been established. We therefore investigated female reproduction in mice expressing progressively rising serum levels of transgenic human FSH (Tg-FSH, 2.5-10 IU/liter) independently of follicle depletion. We show that serum LH and estradiol levels and uterine size remained normal in Tg-FSH females, whereas ovarian weight and corpora lutea number were significantly increased up to 1.3- and 5-fold, respectively. Furthermore, the monotrophic FSH rise produced a striking biphasic effect on female fertility. Tg-FSH females less than 22 wk old delivered increased litter sizes, then beyond 23 wk, litter sizes decreased rapidly culminating in premature infertility despite continued ovary follicle development, and increased ovulation and uterine embryo implantation sites as well as normal serum levels of anti-Mullerian hormone, a marker of ovarian follicle reserve. We found that rising circulating Tg-FSH produced premature infertility by increasing embryo-fetal resorption and parturition failure with age. Thus, our Tg-FSH mice present a novel paradigm to investigate selective contributions of elevated FSH to age-related female infertility, which revealed that rising FSH levels, despite no exhaustion of ovarian reserve, actively accelerates female reproductive aging primarily by postimplantation reduction of embryo-fetal survival. 相似文献
104.
Antonina A Mikocka-Walus Deborah A Turnbull Jane M Andrews Nicole T Moulding Ian G Wilson Hugh AJ Harley David J Hetzel Gerald J Holtmann 《Clin Pract Epidemiol Ment Health》2008,4(1):15
Background
In independent studies, IBD, IBS and HCV have each been associated with a substantially increased risk of psychological problems such as depression and anxiety and impairment of quality of life compared to the general healthy population. However, the relative psychological burden for each of these diagnoses is unknown as it has never been compared contemporaneously at one institution. Current local data are therefore needed to enable an evidence-based allocation of limited clinical psychological resources.Methods
Overall, 139 outpatients (64 IBD, 41 HCV, and 34 IBS) were enrolled in this cross-sectional study. The HADS, SCL90, SF-12 and appropriate disease-specific activity measures were administered. Differences between groups were assesed with ANOVA, the Chi-Square test and the independent samples t-test (two-tailed).Results
Each of the three groups had significantly lower quality of life than the general population (p < 0.05). Overall, a total of 58 (42%) participants met HADS screening criteria for anxiety and 26 (19%) participants for depression. The HCV group had a significantly higher prevalence of depression than either of the other groups (HCV = 34%, IBS = 15% and IBD = 11%, p = 0.009). In the SCL90, the three disease groups differed on 7 out of 12 subscales. On each of these subscales, the HCV group were most severely affected and differed most from the general population.Conclusion
Patients with these common chronic gastrointestinal diseases have significant impairment of quality of life. Anxiety is a greater problem than depression, although patients with HCV in particular, should be regularly monitored and treated for co-morbid depression. Evaluation of specific psychological interventions targeting anxiety is warranted.105.
A randomized double-blind placebo-controlled crossover study of subcutaneous sumatriptan in general practice 总被引:1,自引:0,他引:1
MB Russell OE Holm-Thomsen M Rishøj Nielsen A Cleal AJ Pilgrim J Olesen 《Cephalalgia : an international journal of headache》1994,14(4):291-296
Objective. To evaluate the therapeutic response to sumatriptan in the acute migraine attack. Material and methods. Two hundred and thirty migraineurs diagnosed by their general practitioners in accordance with their usual practice were included in the study. The patients treated two migraine attacks at home by subcutaneous injection of sumatriptan or placebo for the first attack and the alternative medication, i.e. placebo or sumatriptan, for the second attack (crossover). Following treatment, a neurology resident interviewed and examined the patients, Results. When sumatriptan was compared to placebo, significantly more of the 209 evaluable patients reported headache relief at I h (56% vs 8%, p < 0.001) and 2 h (62% vs 15%, p < 0.001) after the first injection. Resolution of nausea, photophobia, and phonophobia was significantly more common in patients on sumatriptan than in those on placebo ( p < 0.001 for all comparisons). The adverse events were usually transient and of mild or moderate severity; however, three patients withdrew due to adverse events. Ninety-five percent of patients evaluated by a neurology resident met the IHS criteria for migraine. Conclusion. In general practice, sumatriptan taken subcutaneously using an autoinjector at home was an effective and well tolerated acute treatment for migraine. 相似文献
106.
AJ Larner MRCP 《International journal of clinical practice》1994,48(5):272-274
SUMMARY A case is reported of pseudohyperphosphataemia in association with a monoclonal gammopathy of undetermined significance. 相似文献
107.
Allan CM Kalak R Dunstan CR McTavish KJ Zhou H Handelsman DJ Seibel MJ 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(52):22629-22634
Elevated follicle-stimulating hormone (FSH) activity is proposed to directly cause bone loss independent of estradiol deficiency in aging women. Using transgenic female mice expressing human FSH (TgFSH), we now reveal that TgFSH dose-dependently increased bone mass, markedly elevating tibial and vertebral trabecular bone volume. Furthermore, TgFSH stimulated a striking accrual of bone mass in hypogonadal mice lacking endogenous FSH and luteinizing hormone (LH) function, showing that FSH-induced bone mass occurred independently of background LH or estradiol levels. Higher TgFSH levels increased osteoblast surfaces in trabecular bone and stimulated de novo bone formation, filling marrow spaces with woven rather than lamellar bone, reflective of a strong anabolic stimulus. Trabecular bone volume correlated positively with ovarian-derived serum inhibin A or testosterone levels in TgFSH mice, and ovariectomy abolished TgFSH-induced bone formation, proving that FSH effects on bone require an ovary-dependent pathway. No detectable FSH receptor mRNA in mouse bone or cultured osteoblasts or osteoclasts indicated that FSH did not directly stimulate bone. Therefore, contrary to proposed FSH-induced bone loss, our findings demonstrate that FSH has dose-dependent anabolic effects on bone via an ovary-dependent mechanism, which is independent of LH activity, and does not involve direct FSH actions on bone cells. 相似文献
108.
A Hirsch F Windhausen JG Tijssen AJ Oude Ophuis WJ van der Giessen PM van der Zee JH Cornel FW Verheugt RJ de Winter 《European heart journal》2009,30(6):645-654
AIMS: In several observational studies, revascularization is associated with substantial reduction in mortality in patients with non-ST-segment elevation acute coronary syndrome (nSTE-ACS). This has strengthened the belief that routine early angiography would lead to a reduction in mortality. We investigated the association between actual in-hospital revascularization and long-term outcome in patients with nSTE-ACS included in the ICTUS trial. METHODS AND RESULTS: The study population of the present analysis consists of ICTUS participants who were discharged alive after initial hospitalization. The ICTUS trial was a randomized, controlled trial in which 1200 patients were randomized to an early invasive or selective invasive strategy. The endpoints were death from hospital discharge until 4 year follow-up and death or spontaneous myocardial infarction (MI) until 3 years. Among 1189 patients discharged alive, 691 (58%) underwent revascularization during initial hospitalization. In multivariable Cox regression analyses, in-hospital revascularization was independently associated with a reduction in 4 year mortality and 3 year event rate of death or spontaneous MI: hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.37-0.96] and 0.46 (95% CI 0.31-0.68). However, when intention-to-treat analysis was performed, no differences in cumulative event rates were observed between the early invasive and selective invasive strategies: HR 1.10 (95% CI 0.70-1.74) for death and 1.27 (95% CI 0.88-1.85) for death or spontaneous MI. CONCLUSION: The ICTUS trial did not show that an early invasive strategy resulted in a better outcome than a selective invasive strategy in patients with nSTE-ACS. However, similar to retrospective analyses from observational studies, actual revascularization was associated with lower mortality and fewer MI. Whether an early invasive strategy leads to a better outcome than a selective invasive strategy cannot be inferred from the observation that revascularized patients have a better prognosis in non-randomized studies. 相似文献
109.
Irene M Dek Bram DJ van den Elzen Paul Fockens Erik AJ Rauws 《World journal of gastroenterology : WJG》2009,15(19):2423-2424
In this case report we present an elderly patient who was referred to our hospital with recurrent episodes of cholangitis that persisted after placement of five metal stents for a distal common bile duct (CBD) stenosis.All metal stents were endoscopically removed from the CBD by forceps after balloon dilatation of the papilla. A profoundly dilated CBD with sludge and concrements was seen. To ensure adequate bile drainage an enteral metal stent was inserted in the CBD. This case shows that proximally migrated uncovered metal stents in the CBD can be safely removed endoscopically under certain circumstances. We suggest that in the case of a CBD drainage problem due to an extremely dilated CBD, placement of an enteral metal stent in the CBD could be considered, especially in patients who are unfit for surgery. 相似文献
110.
Inactivation of factor XIa in human plasma assessed by measuring factor XIa-protease inhibitor complexes: major role for C1-inhibitor 总被引:2,自引:1,他引:2
Wuillemin WA; Minnema M; Meijers JC; Roem D; Eerenberg AJ; Nuijens JH; ten Cate H; Hack CE 《Blood》1995,85(6):1517-1526
From experiments with purified proteins, it has been concluded that factor XIa (FXIa) is inhibited in plasma mainly by alpha 1-antitrypsin (a1AT), followed by antithrombin III (ATIII), C1-inhibitor (C1Inh), and alpha 2-antiplasmin (a2AP). However, the validity of this concept has never been studied in plasma. We established the relative contribution of different inhibitors to the inactivation of FXIa in human plasma, using enzyme-linked immunosorbent assays (ELISAs) for the quantification of complexes of FXIa with a1AT, C1Inh, a2AP, and ATIII. We found that 47% of FXIa added to plasma formed complexes with C1Inh, 24.5% with a2AP, 23.5% with a1AT, and 5% with ATIII. The distribution of FXIa between these inhibitors in plasma was independent of whether FXIa was added to plasma, or was activated endogenously by kaolin, celite, or glass. However, in the presence of heparin (1 or 50 U/mL), C1Inh appeared to be the major inhibitor of FXIa, followed by ATIII. Furthermore, at lower temperatures, less FXIa-C1Inh and FXIa-a1AT complexes but more FXIa-a2AP complexes were formed. These data demonstrate that the contribution of the different inhibitors to inactivation of FXIa in plasma may vary, but C1Inh is the principal inhibitor under most conditions. 相似文献