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11.
Abstract

Maternal dietary habits influence maternal and foetal health, representing a pathway for intervention to maximise pregnancy outcomes. Advice on energy intake is provided on a trimester basis, with no additional calories required in the first trimester and an additional 340?kcal?d?1 and 452?kcal?d?1 needed for the second and third trimesters. Energy intake depends on pre-gravid body mass index (BMI); underweight women are recommended an increase of 150, 200 and 300?kcal?d?1 during the first, second and third trimester, normal weight women an increase of 0, 350 and 500?kcal?d?1 and obese women an increase of 0, 450 and 350?kcal?day?1. The recommendations for carbohydrate and protein intake are 175?g?d?1 and 0.88–1.1?g?kgBM?d?1, with no change to fat intake. The number of pre-gravid obese women is rising; therefore, we need to regulate weight in women of childbearing age and limit gestational weight gain to within the recommended ranges [overweight women 6.8–11.3?kg and obese women 5.0–9.1?kg]. This can be achieved using nutritional interventions, as dietary changes have been shown to help with gestational weight management. As pregnancy has been identified as a risk factor for the development of obesity, normal weight women should gain 11.5–16.0?kg during pregnancy. While some research has shown that dietary interventions help to regulate gestational weight gain and promote postpartum weight loss to some extent, future research is needed to provide safe and effective guidelines to maximise these effects, while benefitting maternal and foetal health.  相似文献   
12.
The high prevalence of child sexual abuse (CSA) is concerning, particularly as survivors are at increased risk for multiple adverse outcomes, including poor mental health across the lifespan. Children born at an extremely low birth weight (ELBW; <1000 g) and who experience CSA may be a group that is especially vulnerable to psychopathology later in life. However, no research has considered the mental health risks associated with being born at ELBW and experiencing CSA. In this study, we investigated the mental health of 179 ELBW survivors and 145 matched normal birth weight (NBW; >2500 g) participants at ages 22–26 and 29–36. At age 22–26, CSA was associated with increased odds of clinically significant internalizing (OR = 7.32, 95% CI: 2.31–23.23) and externalizing (OR = 4.65, 95% CI: 1.11–19.51) problems among ELBW participants exposed to CSA compared to those who did not, though confidence intervals were wide. At age 29–36, CSA was linked to increased odds of any current (OR = 3.43, 95% CI: 1.08–10.87) and lifetime (OR = 7.09, 95% CI: 2.00–25.03) non-substance use psychiatric disorders, however, this did not hold after adjustment for covariates. Statistically significant differences in mental health outcomes were not observed in NBW participants exposed to CSA compared to NBW participants who were not exposed. Survivors of significant perinatal adversity who are also exposed to CSA may be at higher risk for psychopathology through the fourth decade of life.  相似文献   
13.
采用Galerkin方法来构造适当的基函数,计算一类微分算子特征值的近似值,且可用第n次近似值来估计第n-1次近似值的精确度.随着n的增大,特征值λk的精确度逐步提高,只要适当选取n,就可以求得所需精确度的特征值的近似值,此算法具有一定的实用价值和理论价值.  相似文献   
14.
The aims of this study were to describe normative values and seasonal variation of body composition in female cyclists comparing female road and track endurance cyclists, and to validate the use of anthropometry to monitor lean mass changes. Anthropometric profiles (seven site skinfolds) were measured over 16 years from 126 female cyclists. Lean mass index (LMI) was calculated as body weight?×?skinfolds?x. The exponent (x) was calculated as the slope of the natural logarithm of body weight and skinfolds. Percentage changes in LMI were compared to lean mass changes measured using dual-energy X-ray absorptiometry (DXA) in a subset of 25 road cyclists. Compared to sub-elite and elite cyclists, world class cyclists were (mean [95% CI]) 1.18?kg [0.46, 1.90] and 0.60?kg [0.05, 1.15] lighter and had skinfolds that were 7.4?mm [3.8, 11.0] and 4.6?mm [1.8, 7.4] lower, respectively. Body weight (0.41?kg [0.04, 0.77]) and skinfolds (4.0?mm [2.1, 6.0]) were higher in the off-season compared to the early-season. World class female road cyclists had lower body weight (6.04?kg [2.73, 9.35]) and skinfolds (11.5?mm [1.1, 21.9]) than track endurance cyclists. LMI (mean exponent 0.15 [0.13, 0.18]) explained 87% of the variance in DXA lean mass. In conclusion, higher performing female cyclists were lighter and leaner than their less successful peers, road cyclists were lighter and leaner than track endurance cyclists, and weight and skinfolds were lowest early in the season. LMI appears to be a reasonably valid tool for monitoring lean mass changes.  相似文献   
15.
ABSTRACT

This article will describe how merging service points in an academic library is an opportunity to improve customer service and utilize staffing resources more efficiently. Combining service points provides libraries with the ability to create a more positive library experience for patrons by minimizing the ping-pong effect for assistance. The Access Services Department at the University of North Texas Libraries was charged with management of the circulation and reference services offered at the service desk. Streamlined planning and modernized management of the desk and its impact on customer service in a changing library environment will be discussed.  相似文献   
16.
单片机开发应用中经常用到延时控制,延时控制的基本方法有纯软件、纯硬件及软硬件结合方法,它们都有各自的特点及应用范围,以1秒延时为例给出用三种方法实现的过程,并介绍了软硬件结合延时的应用实例。  相似文献   
17.
深入分析了“顺穿法”和“花穿法”绕制的单行并联式滑车组在起重工作时的受力性能,通过对滑车组的偏心距和倾斜角计算,证明偏心距及倾斜角较大时对滑车组的工作和使用寿命存在很不利的影响。详细分析了混联式滑车的构造和受力性能,并对其起重时的偏心及倾斜角进行了计算,计算结果表明该新型滑车组在构造和技术上具有明显的优越性。混联式滑车于1996年获得国家发明专利。  相似文献   
18.
基于遗传算法和BP神经网络的优化设计方法   总被引:5,自引:0,他引:5  
随着生产规模的复杂化、多维化和非线性等复杂特性的增加,对生产中高效的优化技术要求也越来越迫切,利用并行遗传算法和BP网络的优点,提出采用遗传算法的并行搜索和解空间搜索的优点进行网络参数的选取,利用BP网络简单和可塑性强的优点来优化样本空间,以取得整体的优化效率。  相似文献   
19.
随机数是蒙特卡罗(Monte Carlo)方法的关键因素.首先给出一种广义反馈位移寄存器发生器及其缺点,然后在此基础上提出一种基于两个广义反馈位移寄存器方法的组合随机数发生器,最后给出一些严密的统计检验,结果证明这种组合随机数发生器不失为一种较好的随机数发生器.  相似文献   
20.
本文对组合式因素神经网络系统的组成结构进行了分析和论述,作出了数学描述.  相似文献   
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