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71.

Background

Our objective was to examine the effect of antenatal peer support on rates of breastfeeding initiation.

Methods

We performed a systematic review of randomized controlled trials, quasi-randomized trials and cohort studies with concurrent controls. We searched the Cochrane Library, MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the National Research Register and the British Nursing Index from inception or from 1980 to 2009. We carried out study selection, data abstraction and quality assessment independently and in duplicate. We defined high-quality studies as those that minimized the risk of at least three of the following types of bias: selection, performance, measurement and attrition bias. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) for individual studies and undertook separate meta-analyses for high-quality trials of universal peer support and targeted peer support. We did not include low-quality studies.

Results

We selected 11 studies, which involved 5445 women in total. Seven of these studies (involving 4416 women in total) evaluated universal peer support, and four studies (involving 1029 women in total) targeted antenatal peer support. In the three high-quality studies of universal peer support, all involving low-income women, the relative risk for not initiating breastfeeding was 0.96 (95% CI 0.76–1.22). In the three high-quality studies of antenatal peer support that targeted women considering breastfeeding, the relative risk for not initiating breastfeeding was 0.64 (95% CI 0.41 – 0.99).

Interpretation

Universal antenatal peer support does not appear to improve rates of breastfeeding initiation, but targeted antenatal peer support may be beneficial. This effect may be related to context, however, so any new peer-support program should undergo concurrent high-quality evaluation.Breastfeeding confers numerous benefits for mother and infant,13 yet many women still do not initiate breastfeeding.4 The World Health Organization recommends exclusive breastfeeding to six months,5 and national governments have implemented initiatives to increase initiation rates.6,7 Peer support has been examined as one intervention to increase breastfeeding rates, but there have been few high-quality randomized controlled trials (RCTs) examining initiation. One systematic review8 (published in 2000) concluded, based only on two nonrandomized studies, that antenatal peer support had a positive effect on breastfeeding initiation. Another9 (published in 2005 and updated in 2007) included only RCTs but excluded those whose primary purpose was to affect duration. Based only on one RCT, that review concluded that peer support is likely to result in improvements in initiation of breastfeeding among low-income women where baseline breastfeeding rates are low. These weaknesses in the available evidence make recommendations uncertain. Despite this uncertainty, antenatal peer support for breastfeeding is being incorporated into routine maternity care in some parts of the world.10Antenatal peer support can be provided as a universal service or targeted to women who are considering breastfeeding. Although trials have made this distinction, previous reviews have not. New evidence has become available, and it appears appropriate to re-examine antenatal peer support through a systematic review. The purpose of our review was to assess the effectiveness of antenatal peer support, as either a universal or a targeted service, including all studies that examined breastfeeding initiation using concurrent controls.  相似文献   
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The pathogenetic role of anticardiolipin antibodies (aCLs) in patients with neuropsychiatric systemic lupus erythematosus (NPSLE) without cerebral infarcts remains elusive. Magnetization transfer imaging (MTI) has proved to be a sensitive tool for detecting diffuse microscopic brain damage in NPSLE patients. In this study we examined the correlation between grey and white matter magnetization transfer ratio (MTR) parameters and the presence of IgM and IgG aCLs and lupus anticoagulant in 18 patients with systemic lupus erythematosus and a history of NPSLE but without cerebral infarcts on conventional magnetic resonance imaging. Lower grey matter mean MTR (P < 0.05), white matter mean MTR (P < 0.05), white matter peak location (P < 0.05) and grey matter peak location (trend toward statistical significance) were observed in IgM aCL-positive patients than in IgM aCL-negative patients. No significant differences were found in MTR histogram parameters with respect to IgG aCL and lupus anticoagulant status, nor with respect to anti-dsDNA or anti-ENA (extractable nuclear antigen) status. This is the first report of an association between the presence of aCLs and cerebral damage in grey and white matter in NPSLE. Our findings suggest that aCLs are associated with diffuse brain involvement in NPSLE patients.  相似文献   
74.
比较了不同季节和冬眠时相中达乌尔黄鼠 (Citelleusdauricus)下丘脑内去甲肾上腺素 (noradrenaline ,NA)代谢和视前区 (POA)脑片中各类温敏神经元的比例、温度敏感性、放电活动的临界温度及下限温度 .结果表明 :与夏季动物相比 ,( 1)冬眠各时相中POA温敏神经元的比例和温敏性产生了与冬眠体温调节特性相关的适应性改变 ;( 2 )冬季和冬眠中POA神经元放电的下限温度和温敏神经元活动的临界温度均显著下移 ;( 3 )冬眠中POA神经元对NA反应的敏感性增高 ,冷敏神经元对NA的反应从夏季的抑制型转变为冬眠时的兴奋型 ;( 4)入眠和深冬眠时下丘脑内NA的含量和代谢水平下降 ,出眠时代谢水平升高 .这些变化可能解释动物入眠时主动降低体温和出眠时从深低体温中快速地升温的温度调节机理 .  相似文献   
75.
Mice with a natural infection of Syphacia obvelata and Aspiculuris tetraptera were continuously medicated with 0.1% thiabendazole in the diet. No oxyurids were found in test animals after 24 days of treatment though control animals remained infected. Growth rates in treated animals increased. 2 generations of mice were studied and, although overall production fell by 1.45%, the use of this drug in total eradication of the worms is suggested.  相似文献   
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目的:探讨胸内正压对正常人左室射血及充盈的影响及其力学原理。方法:超声心动图观测30例正常人初始时与标准乏氏动作张力期10s时左室舒张末容积(LVEDV)、左室收缩末容积(LVESV)、每搏量(SV)、射血分值(EF)、流入道血流速度(E峰、A峰)、E/A值、二尖瓣环舒张早期运动速度(e)及舒张早期充盈压(E/e)的变化。结果:与初始时比较,标准乏氏动作张力期LVEDV、LVESV及SV减低而心率(陬)增快(P均〈0.001),EF值增加,但无统计学意义(P〉0.05);E峰与E/A值减低(P均〈O.05);e没有变化(P〉0.05).E/e值减低(P〈O.05)。结论:胸内正压对左室游离壁的力学作用促进了左室收缩运动而阻碍了左室舒张运动,会引起EF值增加,E峰及E/A值减低;2,胸内正压降低了肺静脉系统与心脏的跨壁压力,增加了血流阻力也是导致肺静脉系统与左室血液回流减少.E峰减低.E/e值减低的一个原因。  相似文献   
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