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Objective: The objective of this study is to assess the safety of vaginal delivery in VLBW singletons in the vertex presentation.

Methods: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science databases were searched for studies on mode of delivery and neonatal outcome in VLBW singletons in the vertex presentation. A total of 28 studies met our inclusion criteria.

Results: Vaginal delivery was not associated with an increase in overall neonatal mortality compared with cesarean delivery (OR 0.87, 95% CI 0.72–1.04). Vaginal delivery was associated with a significant decrease in mortality for the 1250–1500?g birthweight category (OR 0.57, 95% CI 0.36–0.92), while an increase in mortality in the 500–750?g category was not significant (OR 1.5, 95% CI 0.86–2.61). Severe intraventricular hemorrhage (IVH) was not associated with mode of delivery (OR 1.05, 95% CI 0.85–1.29), but the only two high quality study that assessed IVH of all grades found an increase in risk for IVH in vaginal delivery (OR 1.33, 95% CI 1.16–1.51).

Conclusions: Vaginal delivery does not appear to increase the risk for neonatal mortality. However, current available data on neonatal morbidity are limited. More high-quality studies are needed to assess the association between mode of delivery and neonatal morbidity.  相似文献   
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In order to prepare fully competent health care professionals, health professions education must be concerned with the relational space between patients and providers. Compassion and compassionate care are fundamental elements of this relational space. Traditionally, health professions educators and leaders have gone to two narrative sources when attempting to better under constructs of compassion: patients or providers. Rarely have there been explorations of the perspectives of those who consider themselves as both patients and providers. In this study, we interviewed nineteen health care providers who self-disclosed as having had a substantive patient experience in the health care system. We engaged with these participants to better understand their experience of having these dual roles. Anchored in Foucault’s concepts of subjectivity and Goffman’s symbolic interactionism, the interviews in this study reveal practices of moving between the two roles of patient and provider. Through this exploration, we consider how it is that providers who have been patients understand themselves to be more compassionate whilst in their provider roles. Rather than describing compassion as a learnable behaviour or an innate virtue, we theoretically engage with one proposed mechanism of how compassion is produced. In particular, we highlight the role of critical reflexivity as an underexplored construct in the enactment of compassion. We discuss these findings in light of their implications for health professions education.  相似文献   
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The purpose of this study was to explore the effect of two awareness activities on children's attitudes towards peers with a disability. The Children's Attitudes towards Peers with Disability scale including cognitive, behavioral and emotional subscales was administered before and after two types of short-term interventions. The first included 75 children from grades 7-9, who actively participated in the workshop simulating movement activities. The second intervention included 121 students of the 10th grade, who observed their peers participating in a wheelchair-basketball activity together with elite wheelchair-basketball players. Results indicated significant effects in the cognitive and behavioral domains. Post-test findings confirmed that intervention bridged the difference in the cognitive domain observed between those with and without previous contact at pretest.  相似文献   
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Background

Aortic stenosis is associated with concentric left ventricle (LV) hypertrophy or remodeling resulting in impaired diastolic function and elevated left-sided filling pressure. We investigated the changes in LV geometry and LV filling hemodynamics, giving emphasis to parameters associated with changes in diastolic function after transcatheter aortic valve implantation (TAVI).

Methods

Comprehensive diastolic assessment was performed before and six months after TAVI in 70 patients with severe aortic stenosis. Patients with any degree of mitral stenosis or >mild left-sided valvular regurgitation were excluded.

Results

In the entire cohort six months after TAVI, LV end-diastolic diameter increased (44.1 ± 6 versus 45 ± 6 mm, P = 0.02), whereas LV mass and relative wall thickness (RWT) decreased (270.1 ± 76 versus 245.1 ± 75 g and 0.53 ± 0.15 versus 0.46 ± 0.1, respectively; P < 0.0001 for both). Lateral e′ increased (5.8 ± 2 versus 6.6 ± 3 cm/s, P = 0.03) and left atrium (LA) volume, E/e′ ratio, and systolic pulmonary pressure decreased (88.1 ± 30 versus 80 ± 28 cc, 18 ± 7.8 versus 16.3 ± 5.5, and 42.7 ± 14.9 versus 38.7 ± 12 mmHg, respectively; P < 0.05 for all), suggesting reduction in LA pressure. The improvement in LA volume and E/e′ was almost exclusively seen in patients with LV hypertrophy before TAVI (P < 0.05 both), as opposed to patients with concentric remodeling.

Conclusions

In our preliminary study, TAVI resulted in LV and LA reverse remodeling, and improved LV relaxation and LA filling pressure in patients with severe aortic stenosis and concentric hypertrophy. Patients with concentric remodeling at baseline seem to have limited improvement in LV diastolic function and filling pressure following TAVI, but larger clinical trials would be required to conclude if they have no improvement at all.  相似文献   
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Freier S  Weiss O  Eran M  Flyvbjerg A  Dahan R  Nephesh I  Safra T  Shiloni E  Raz I 《Gut》1999,44(5):704-708
AIMS: To study changes in the expression of insulin-like growth factors (IGFs) and their receptors, as well as production of the IGF-I and IGF-II polypeptides, in adenocarcinoma of the colon. METHODS: Malignant tissue obtained at operation was used. Total RNA was extracted and specific IGF-I and IGF-II and their receptor mRNAs were measured by a solution hybridisation RNase protection assay. IGF-I and IGF-II polypeptides were measured by specific immunoassays. RESULTS: All normal tissues expressed IGF-II, IGF-I receptor, and IGF-II/mannose-6-phosphate (Man-6-P) receptor. IGF-I mRNA could not be detected but the polypeptide was present in small but equal amounts in normal and malignant tissue. IGF-II was expressed 40 times more abundantly in colonic tumours than in adjacent normal tissue and the concentration of the corresponding polypeptide was twice as high in the malignant tissue. IGF-I receptor expression was increased by a factor of 2.5 and IGF-II/Man-6-P receptor by a factor of 4. CONCLUSIONS: This study confirms that in adenocarcinoma of the human colon there is increased expression of IGF-I receptor and IGF-II. Furthermore, IGF-II/Man-6-P receptor message is increased and the increase in IGF-II message is accompanied by a doubling of the IGF-II protein in the tumour tissue compared with the adjacent normal tissue. These findings suggest that the IGF-II/Man-6-P receptor may also be involved in development of adenocarcinoma of the colon. There is rapidly accumulating evidence implicating the IGF system in the development of malignancy of the large bowel.  相似文献   
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