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   350篇
  免费   14篇
耳鼻咽喉   7篇
儿科学   17篇
妇产科学   78篇
基础医学   62篇
临床医学   14篇
内科学   44篇
皮肤病学   3篇
神经病学   10篇
特种医学   7篇
外科学   13篇
综合类   3篇
一般理论   1篇
预防医学   50篇
眼科学   29篇
药学   18篇
中国医学   3篇
肿瘤学   5篇
  2022年   4篇
  2021年   3篇
  2019年   8篇
  2018年   5篇
  2017年   7篇
  2015年   7篇
  2014年   7篇
  2013年   22篇
  2012年   14篇
  2011年   12篇
  2010年   11篇
  2009年   5篇
  2008年   10篇
  2007年   27篇
  2006年   25篇
  2005年   12篇
  2004年   19篇
  2003年   16篇
  2002年   14篇
  2001年   19篇
  2000年   15篇
  1999年   13篇
  1998年   7篇
  1997年   4篇
  1996年   3篇
  1995年   3篇
  1994年   5篇
  1993年   9篇
  1992年   6篇
  1991年   2篇
  1990年   3篇
  1988年   3篇
  1987年   2篇
  1985年   4篇
  1984年   2篇
  1983年   2篇
  1979年   4篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1974年   3篇
  1973年   2篇
  1972年   5篇
  1971年   2篇
  1970年   1篇
  1966年   1篇
  1964年   1篇
  1962年   1篇
  1960年   1篇
  1910年   1篇
排序方式: 共有364条查询结果,搜索用时 15 毫秒
131.
The olfactory bulbectomy (OB) is an animal model of depression that results in behavioral, neurochemical and neuroendocrinological changes, features comparable to those seen in depressive patients. This study investigated OB-induced alterations in locomotor activity and exploratory behavior in the open-field test, self-care and motivational behavior in the splash test, hyperactivity in the novel object test and novel cage test, and the influence of chronic treatment with fluoxetine (10 mg/kg, p.o., once daily for 14 days) on these parameters. Fluoxetine reversed OB-induced hyperactivity in the open-field test, locomotor hyperactivity and the increase in exploratory behavior induced by novelty in the novel object and novel cage tests, and the loss of self-care and motivational behavior in the splash test. Moreover, OB decreased the number of grooming and fecal boli in the open-field and novel cage tests, alterations that were not reversed by fluoxetine. OB caused an increase in hippocampal, but not in prefrontal acetylcholinesterase (AChE) activity. Fluoxetine was able to reverse the increase in hippocampal AChE activity induced by OB. Serum corticosterone was increased in SHAM and bulbectomized mice treated with fluoxetine. In conclusion, OB mice exhibited depressive-like behaviors associated with an increase in hippocampal AChE activity, effects that were reversed by chronic treatment with fluoxetine.  相似文献   
132.
133.
Polycystic ovary syndrome (PCOS), insulin resistance and overall mortality due to diabetes and coronary artery disease are higher in South Asians than in Caucasians. Aims: We compared the prevalence of the C677T and A1298C single nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene in South Asian and Caucasian women, its association with folate and homocysteine (Hcy) metabolism, and its relevance to future atherogenic events. Methods and results: 71 women were recruited for the study: South Asian PCOS (21) plus controls (9) and Caucasian PCOS (25) plus controls (16). Anthropometric and laboratory parameters were compared. South Asian PCOS women were significantly hyperandrogenic and exhibited a greater degree of insulin resistance. Caucasian PCOS women had higher plasma Hcy concentrations with a 1.9 times higher frequency of the T allele than the South Asian PCOS group. In the presence of this variant allele, plasma Hcy levels appear to be higher in both PCOS groups. The South Asians had a 1.8 times higher frequency of the C allele than the Caucasians; however, the overall frequency was comparable in the two PCOS groups. The frequency of homozygosity, i.e. TT677 and CC1298, was 7.2% and 4.9% in the Caucasians and 0% and 16.6% in the South Asian recruits, respectively.

Dietary inadequacies in the South Asian women can influence their plasma folate and B12 concentrations resulting in hyperhomocysteinemia which, in combination with dyslipidaemia and insulin resistance, can lead to long-term atherogenic consequences. Conclusions: Current data suggests that the mechanisms of atherothrombosis have separate pathways in the two ethnic groups. Larger studies exploring the current theme need to be carried out in the PCOS groups to obtain adequate insight.  相似文献   
134.
135.
The zoonotic risk of hepatitis E virus(HEV) is well established. The HEV seroprevalence rates vary according to geographical region, assays used, and study cohorts. HEV infection is still underdiagnosed, implying the need to evaluate the disease's burden in the general population and specific risk groups, such as professionally exposed. Close contact with various animal reservoirs such as pigs, rabbits, sheep, dogs, wild boars, and deer has been associated with higher anti-HEV seroprevalence as a part of occupational exposure. While exact transmission routes remain to be determined, some general preventive measures such as proper hand hygiene, the usage of personal protective equipment, and the thermal processing of food before consumption should be followed. A "OneHealth" multisectoral approach should be implemented to achieve optimal health and well-being outcomes, recognizing the interconnections between humans, animals, plants, and their shared environment, in which a vaccine against the zoonotic genotypes 3 and 4 and swine vaccination should be considered as a possible public health measure. This opinion review comprehensively addresses the HEV burden of professional exposure for butchers, slaughterhouse workers, veterinarians, farmers, hunters, and forestry workers delineates the current limits of protective work measures, and tackles future directions.  相似文献   
136.

Background  

Polycystic ovary syndrome (PCOS) is the most common chronic endocrine disorder affecting women of reproductive age. This study aimed to compare the HRQoL of South Asian and white Caucasian women with PCOS, given that it is particularly common among women of South Asian origin and they have been shown to have more severe symptoms.  相似文献   
137.

Objective

To review empirical studies on families created by new reproductive technologies (NRT) in which only one parent has a genetic link to the child.

Methodology

Literature search was conducted among computerized databases. Inclusion criteria were that studies should focus on childrearing or parenting, as well as on the psychological adjustment of children in: heterosexual families formed through artificial insemination with donated semen (AID), single-mother AID families, oocyte-donation families, planned lesbian-mother families, planned gay-father families, and partial surrogacy families.

Results

Compared to natural-conception parents, parents in these NRT families have better relationships with their children, and their children are functioning well.

Conclusion

Although several studies show that parents in NRT families are more emotionally involved in their parenting than are parents in naturally conceived families, no empirical evidence was found that the psychological adjustment of children in NRT families differs from that of their counterparts in natural-conception families.

Practical implication

The results inform counselors and infertile couples that concerns regarding the use of NRT in relation to negative consequences for the parent-child relationship or the psychological adjustment of the child are till now unfounded.  相似文献   
138.
OBJECTIVE: To assess the influence of body weight on the outcome of ovulation induction in women with World Health Organization (WHO) group II anovulatory infertility. DESIGN: The combined results of two studies in which either a highly purified urinary follicle-stimulating hormone or highly purified urinary menotrophin were compared with recombinant follicle-stimulating hormone. SETTING: Thirty-six fertility clinics. POPULATION: A total of 335 women with WHO group II anovulatory infertility failing to ovulate or conceive on clomifene citrate. METHODS: Ovarian stimulation using a low-dose step-up protocol. MAIN OUTCOME MEASURES: The effects of body weight on ovarian response, ovulation rate and pregnancy rate after one treatment cycle. RESULTS: With increasing body mass index (BMI), a higher threshold dose of gonadotrophins was required and there were more days of stimulation; yet, despite a greater concentration of antral follicles, there were fewer intermediate and large follicles. There was no difference in the rates of ovulation and clinical pregnancy in relation to body weight. CONCLUSIONS: Body weight affects gonadotrophin requirements but not overall outcome of ovulation induction in women with anovulatory polycystic ovary syndrome and a BMI of less than 35 kg/m2.  相似文献   
139.

Background

There are growing concerns regarding inequities in health, with poverty being an important determinant of health as well as a product of health status. Within the People's Republic of China (P.R. China), disparities in socio-economic position are apparent, with the rural-urban gap of particular concern. Our aim was to compare direct and proxy methods of estimating household wealth in a rural and a peri-urban setting of Hunan province, P.R. China.

Methods

We collected data on ownership of household durable assets, housing characteristics, and utility and sanitation variables in two village-wide surveys in Hunan province. We employed principal components analysis (PCA) and principal axis factoring (PAF) to generate household asset-based proxy wealth indices. Households were grouped into quartiles, from 'most wealthy' to 'most poor'. We compared the estimated household wealth for each approach. Asset-based proxy wealth indices were compared to those based on self-reported average annual income and savings at the household level.

Results

Spearman's rank correlation analysis revealed that PCA and PAF yielded similar results, indicating that either approach may be used for estimating household wealth. In both settings investigated, the two indices were significantly associated with self-reported average annual income and combined income and savings, but not with savings alone. However, low correlation coefficients between the proxy and direct measures of wealth indicated that they are not complementary. We found wide disparities in ownership of household durable assets, and utility and sanitation variables, within and between settings.

Conclusion

PCA and PAF yielded almost identical results and generated robust proxy wealth indices and categories. Pooled data from the rural and peri-urban settings highlighted structural differences in wealth, most likely a result of localized urbanization and modernization. Further research is needed to improve measurements of wealth in low-income and transitional country contexts.  相似文献   
140.
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