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排序方式: 共有1113条查询结果,搜索用时 18 毫秒
81.
Mark P. Hehir Zachary Rubeo Karen Flood Anne H. Mardy Colm O’Herlihy Peter C. Boylan Mary E. D’Alton 《International urogynecology journal》2018,29(3):377-381
Introduction and hypothesis
Shoulder dystocia is an obstetric emergency that occurs in 0.2–3% of all cephalic vaginal deliveries. We hypothesized that because of the difficult nature of deliveries complicated by shoulder dystocia, the condition may be associated with anal sphincter injury. We sought to identify risk factors for obstetric anal sphincter injury in women with shoulder dystocia.Methods
This retrospective analysis included all cases of shoulder dystocia from 2007 to 2011 at two large tertiary referral centers, in the USA and Ireland. Details of maternal demographics, intrapartum characteristics, and delivery outcomes in cases of shoulder dystocia were analyzed. Univariate and multivariate analyses were used to describe the association between shoulder dystocia and anal sphincter injury.Results
There were 685 cases of shoulder dystocia, and the rate of shoulder dystocia was similar at both institutions. The incidence of anal sphincter injury was 8.8% (60 out of 685). The rate was 14% (45 out of 324) in nulliparas and 4.2% (15 out of 361) in multiparas. Women with sphincter injury were more likely to be nulliparous (75% [45 out of 60] vs 45% [279 out of 625]; p < 0.0001), have had an operative vaginal delivery (50% [30 out of 60] vs 36% [226 out of 625]; p = 0.03) and require internal maneuvers (50% [30 out of 60] vs 32% [198 out of 625], p = 0.004) than those with an intact sphincter. On multivariate regression analysis, these predictors of sphincter injury remained significant when adjusted for other risk factors. Episiotomy was negatively associated with sphincter injury on multivariate regression analysis.Conclusions
In a retrospective cohort of 685 women with shoulder dystocia, the risk of anal sphincter injury is 9%. Risk factors include nulliparity, operative vaginal delivery, and use of internal maneuvers, whereas episiotomy was found to have a protective effect against anal sphincter injury during cases of shoulder dystocia.82.
The significance of receptor status discordance between breast cancer primary and brain metastasis
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83.
Is the P300 wave an endophenotype for schizophrenia? A meta-analysis and a family study 总被引:7,自引:0,他引:7
Bramon E McDonald C Croft RJ Landau S Filbey F Gruzelier JH Sham PC Frangou S Murray RM 《NeuroImage》2005,27(4):1144-968
INTRODUCTION: We assessed the usefulness of the P300 wave as endophenotype for schizophrenia by means of a meta-analysis of the literature as well as our own family study. METHOD: Meta-analysis: We conducted a systematic search for articles published between 1983 and 2003 that reported P300 measures in non-psychotic relatives of schizophrenic patients and in healthy controls. Meta-regression analyses were performed using a random effects procedure. The pooled standardized effect size (PSES) was calculated as the difference between the means of the two groups divided by the common standard deviation. Local study: We examined the P300 wave with a standard two-tone oddball paradigm in 30 patients with schizophrenia, 40 non-psychotic relatives, and 40 controls using linear mixed models. RESULTS: Meta-analysis: We pooled 472 relatives and 513 controls. The P300 amplitude was significantly reduced in relatives (PSES = 0.61; 95% CI: 0.30 to 0.91; P < 0.001). The P300 latency was significantly delayed in relatives (PSES of -0.50; 95% CI: -0.88 to -0.13; P = 0.009]. Local study: The patients showed a trend for amplitude reductions (P = 0.06) and significant latency delays (P < 0.01). The relatives displayed normal amplitude but had significant latency delays (P = 0.01). The P300 amplitude and especially the P300 latency are promising alternative phenotypes for genetic research into schizophrenia. 相似文献
84.
Kinter AL Hennessey M Bell A Kern S Lin Y Daucher M Planta M McGlaughlin M Jackson R Ziegler SF Fauci AS 《The Journal of experimental medicine》2004,200(3):331-343
Human immunodeficiency virus (HIV) disease is associated with loss of CD4(+) T cells, chronic immune activation, and progressive immune dysfunction. HIV-specific responses, particularly those of CD4(+) T cells, become impaired early after infection, before the loss of responses directed against other antigens; the basis for this diminution has not been elucidated fully. The potential role of CD25(+)CD4(+) regulatory T cells (T reg cells), previously shown to inhibit immune responses directed against numerous pathogens, as suppressors of HIV-specific T cell responses was investigated. In the majority of healthy HIV-infected individuals, CD25(+)CD4(+) T cells significantly suppressed cellular proliferation and cytokine production by CD4(+) and CD8(+) T cells in response to HIV antigens/peptides in vitro; these effects were cell contact dependent and IL-10 and TGF-beta independent. Individuals with strong HIV-specific CD25(+) T reg cell function in vitro had significantly lower levels of plasma viremia and higher CD4(+): CD8(+) T cell ratios than did those individuals in whom this activity could not be detected. These in vitro data suggest that CD25(+)CD4(+) T reg cells may contribute to the diminution of HIV-specific T cell immune responses in vivo in the early stages of HIV disease. 相似文献
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86.
Carolyn Holladay Sunny‐Akogwu Abbah Colm O'Dowd Abhay Pandit Dimitrios I. Zeugolis 《Journal of tissue engineering and regenerative medicine》2016,10(9):783-798
Tendon injuries are increasingly prevalent around the world, accounting for more than 100 000 new clinical cases/year in the USA alone. Cell‐based therapies have been proposed as a therapeutic strategy, with recent data advocating the use of tendon stem cells (TSCs) as a potential cell source with clinical relevance for tendon regeneration. However, their in vitro expansion is problematic, as they lose their multipotency and change their protein expression profile in culture. Herein, we ventured to assess the influence of insulin‐like growth factor 1 (IGF‐1), growth and differentiation factor‐5 (GDF‐5) and transforming growth factor‐β1 (TGFβ1) supplementation in TSC culture. IGF‐1 preserved multipotency for up to 28 days. Upregulation of decorin and scleraxis expression was observed as compared to freshly isolated cells. GDF‐5 treated cells exhibited reduced differentiation along adipogenic and chondrogenic pathways after 28 days, and decorin, scleraxis and collagen type I expression was increased. After 28 days, TGFβ1 supplementation led to increased scleraxis, osteonectin and collagen type II expression. The varied responses to each growth factor may reflect their role in tendon repair, suggesting that: GDF‐5 promotes the transition of tendon stem cells towards tenocytes; TGFβ1 induces differentiation along several pathways, including a phenotype indicative of fibrocartilage or calcified tendon, common problems in tendon healing; and IGF‐1 promotes proliferation and maintenance of TSC phenotypes, thereby creating a population sufficient to have a beneficial effect. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Studies of non-steroidal anti-inflammatory drugs (NSAIDs) in rheumatoid arthritis imply that inflammation is important in
the development of Alzheimer’s disease (AD). However, these drugs have not alleviated the symptoms of AD in those who have
already developed dementia. This suggests that the primary mediator targeted by these drugs, PGE2, is not actively suppressing
memory function in AD. Amyloid-β oligomers appear to be important for the mild cognitive changes seen in AD transgenic mice,
yet amyloid immunotherapy has also proven unsuccessful in clinical trials. Collectively, these findings indicate that NSAIDs
may target a prodromal process in mice that has already passed in those diagnosed with AD, and that synaptic and neuronal
loss are key determinants of cognitive dysfunction in AD. While the role of inflammation has not yet become clear, inflammatory
processes definitely have a negative impact on cognitive function during episodes of delirium during dementia. Delirium is
an acute and profound impairment of cognitive function frequently occurring in aged and demented patients exposed to systemic
inflammatory insults, which is now recognised to contribute to long-term cognitive decline. Recent work in animal models is
beginning to shed light on the interactions between systemic inflammation and CNS pathology in these acute exacerbations of
dementia. This review will assess the role of prostaglandin synthesis in the memory impairments observed in dementia and delirium
and will examine the relative contribution of amyloid, synaptic and neuronal loss. We will also discuss how understanding
the role of inflammatory mediators in delirious episodes will have major implications for ameliorating the rate of decline
in the demented population. 相似文献