首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   47篇
  免费   11篇
儿科学   9篇
基础医学   10篇
口腔科学   1篇
临床医学   8篇
内科学   9篇
神经病学   9篇
外科学   6篇
预防医学   1篇
药学   3篇
肿瘤学   2篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2020年   1篇
  2019年   4篇
  2018年   4篇
  2017年   6篇
  2016年   2篇
  2015年   2篇
  2014年   2篇
  2013年   5篇
  2012年   7篇
  2011年   7篇
  2010年   3篇
  2009年   1篇
  2008年   1篇
  2007年   1篇
  2006年   2篇
  2005年   2篇
  2003年   2篇
  1990年   1篇
排序方式: 共有58条查询结果,搜索用时 15 毫秒
11.
Breast milk feeding (BMF) is associated with lower neonatal morbidity in the very preterm infant (<32 weeks gestation) and breastfeeding is beneficial for maternal health. Previous studies show large variations in BMF after very preterm birth and recognize the need for targeted breastfeeding support in the neonatal intensive care units (NICU). In a European collaboration project about evidence‐based practices after very preterm birth, we examined the association between maternal, obstetric, and infant clinical factors; neonatal and maternal care unit policies; and BMF at discharge from the NICU. In multivariable analyses, covariates associated with feeding at discharge were first investigated as predictors of any BMF and in further analysis as predictors of exclusive or partial BMF. Overall, 58% (3,826/6,592) of the infants received any BMF at discharge, but there were large variations between regions (range 36–80%). Primiparity, administration of antenatal corticosteroids, first enteral feed <24 hr after birth, and mother's own milk at first enteral feed were predictors positively associated with any BMF at discharge. Vaginal delivery, singleton birth, and receiving mother's own milk at first enteral feed were associated with exclusive BMF at discharge. Units with a Baby Friendly Hospital accreditation improved any BMF at discharge; units with protocols for BMF and units using donor milk had higher rates of exclusive BMF at discharge. This study suggests that there is a high potential for improving BMF through policies and support in the NICU.  相似文献   
12.
To assess the efficacy of an education- and strengths-based counselling programme to promote antiretroviral therapy (ART) adherence in a cohort of HIV-infected individuals with high prevalence of injection drug use in Estonia. Parallel-group randomized (1:1) controlled trial (RCT). Adults receiving ART in two clinics were followed for 12 months. The trial compared: (i) an intervention (three sessions) incorporated into routine clinic visits, providing education about HIV, ART, the role of adherence, and tailoring regimen to daily routines using problem-solving skills to address adherence barriers versus (ii) usual care (control). Primary and secondary outcomes were self-reported ART adherence (3-day recall) and viral load (respectively). 519 patients were randomized and 82% completed the study. Recent optimal ART adherence (3-day recall ≥95%) was reported by 75.6% in the intervention group and 72.9% of controls at baseline and 76.7% and 67.5%, respectively, at 12 months (RR 1.14, 95% CI 1.00–1.28; adjusted RR 1.13, 95% CI 1.00–1.27). There was no difference in the proportion of patients with undetectable viral load. At 12 months the intervention group reported significantly higher perceptions of ART necessity versus ART concerns [mean ART necessity-concerns differential: intervention group 1.32 (SD 1.22) vs control group 1.08 (SD 1.12); p = 0.048]. All-cause mortality among study participants was 27.7 per 1000 person years (95% CI 15.6–44.8). A brief, clinic-based adherence intervention alone may assist with adherence but lacks impact on viral load at 12 months.  相似文献   
13.
14.
Relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and blood flow speed are key parameters that characterize cerebral hemodynamics. We used contrast-enhanced functional micro-ultrasound (fMUS) imaging employing a disruption-replenishment imaging sequence to quantify these hemodynamic parameters in the anesthetized rat brain. The method has a spatial resolution of about 100μm in-plane and around 600μm through-plane, which is comparable to fMRI, and it has a superior temporal resolution of 40ms per frame. We found no significant difference in rCBV of cortical and subcortical gray matter (0.89±0.08 and 0.61±0.09 times the brain-average value, respectively). The rCBV was significantly higher in the vascular regions on the pial surface (3.89±0.71) and in the area of major vessels in the subcortical gray matter (2.02±0.31). Parametric images of rCBV, rCBF, and blood flow speed demonstrate spatial heterogeneity of these parameters on the 100μm scale. Segmentation of the cortex in arteriolar and venular-dominated regions identified through color Doppler imaging showed that rCBV is higher and flow speed is lower in venules than in arterioles. Finally, we show that the dependence of rCBV on rCBF was significantly different in cortical versus subcortical gray matter: the exponent α in the power law relation rCBV=s·rCBF(α) was 0.37±0.13 in cortical and 0.75±0.16 in subcortical gray matter. This work demonstrates that functional micro-ultrasound imaging affords quantification of hemodynamic parameters in the anesthetized rodent brain. This modality is a promising tool for neuroscientists studying these parameters in rodent models of diseases with a cerebrovascular component, such as stroke, neurodegeneration, and venous collagenosis. It is of particular import for studying conditions that selectively affect arteriolar versus venular compartments.  相似文献   
15.
This study examined the relationship between alcohol/illicit drug use, the Five-Factor Model (FFM) personality traits, aggressiveness (Agg), and hyperactivity (Hyp), and platelet monoamine oxidase (MAO) activity in a population-derived representative sample of preadolescents and adolescents (n=1172). Alcohol and illicit drug use was self-reported. The FFM personality inventories were filled in by mothers of the participants, and Agg and Hyp were rated by their class teachers. Higher scores in extraversion (E), Agg, and Hyp and lower scores in conscientiousness (C) together with older age were significant predictors of more frequent alcohol use in adolescents. No significant association was found between alcohol illicit drug use, and platelet MAO activity.  相似文献   
16.
Abstract

Study design

Retrospective population-based study with mortality follow-up.

Objective

To study mortality, causes and risk factors for death in Estonian patients with traumatic spinal cord injury (TSCI).

Setting

All Estonian hospitals.

Methods

Medical records of patients with TSCI from all regional, central, general, and rehabilitation hospitals in Estonia from 1997 to 2007, were retrospectively reviewed. Mortality status was ascertained as of 31 December 2011. Causes of death were collected from the Estonian Causes of Death Registry. Standardized mortality ratios (SMRs) were calculated for the entire sample and for causes of death. A Cox proportional hazards modeling was used to identify the risk indicators for death.

Results

During the observation period (1997–2011) 162 patients of 595 died. Nearly half of the patients (n = 76) died during the first year after TSCI. The main causes of death were external causes (30%), cardiovascular disease (29%). and suicide (8%). The overall SMR was 2.81 (95% confidence interval 2.40–3.28) and SMR was higher for women than for men (3.80 vs. 2.70). Cause-specific SMRs were markedly elevated for sepsis and suicide. Mortality was significantly affected by the age at the time of injury, neurological level, and extent of the injury as well as the year of TSCI and complications.

Conclusion

Life expectancy is significantly decreased in patients with TSCI in Estonia compared with the general population. Deaths during the first year after the injury have an important impact on statistics. Treatment of cardiovascular diseases, infections, and prevention of suicide are useful for reducing mortality in patients with TSCI.  相似文献   
17.
Functional hyperemia, or the increase in focal perfusion elicited by neuronal activation, is one of the primary functions of the neurovascular unit and a hallmark of healthy brain functioning. While much is known about the hemodynamics on the millimeter to tenths of millimeter-scale accessible by MRI, there is a paucity of quantitative data on the micrometer-scale changes in perfusion in response to functional stimulation. We present a novel methodology for quantification of perfusion and intravascular flow across the 3D microvascular network in the rat somatosensory cortex using two-photon fluorescence microscopy (2PFM). For approximately 96% of responding microvessels in the forelimb representation of the primary somatosensory cortex, brief (~2s) forepaw stimulation resulted in an increase of perfusion 20±4% (mean±sem). The perfusion levels associated with the remaining 4% of the responding microvessels decreased 10±9% upon stimulation. Vessels irrigating regions of lower vascular density were found to exhibit higher flow (p<0.02), supporting the notion that local vascular morphology and hemodynamics reflect the metabolic needs of the surrounding parenchyma. High dispersion (~77%) in perfusion levels suggests high spatial variation in tissue susceptibility to hypoxia. The current methodology enables quantification of absolute perfusion associated with individual vessels of the cortical microvascular bed and its changes in response to functional stimulation and thereby provides an important tool for studying the cellular mechanisms of functional hyperemia, the spatial specificity of perfusion response to functional stimulation, and, broadly, the micrometer-scale relationship between vascular morphology and function in health and disease.  相似文献   
18.

Rationale and objective  

Twin studies suggest that substance use initiation in children and adolescents is determined primarily by environmental influences, whereas the establishment of use patterns is strongly controlled by genetic factors. The present study analysed the effects of the serotonin transporter promoter polymorphism [5-HT transporter gene-linked polymorphic region (5-HTTLPR)] and the α2A-adrenoceptor C-1291G genotype (ADRA2A C-1291G) as well as their interaction effects on alcohol, tobacco and drug use from preadolescence to the late adolescence.  相似文献   
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号