全文获取类型
收费全文 | 38805篇 |
免费 | 2891篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 405篇 |
儿科学 | 1411篇 |
妇产科学 | 1156篇 |
基础医学 | 4945篇 |
口腔科学 | 473篇 |
临床医学 | 5294篇 |
内科学 | 6974篇 |
皮肤病学 | 549篇 |
神经病学 | 3941篇 |
特种医学 | 869篇 |
外国民族医学 | 4篇 |
外科学 | 3653篇 |
综合类 | 416篇 |
一般理论 | 54篇 |
预防医学 | 5391篇 |
眼科学 | 563篇 |
药学 | 2565篇 |
中国医学 | 29篇 |
肿瘤学 | 3069篇 |
出版年
2024年 | 36篇 |
2023年 | 294篇 |
2022年 | 560篇 |
2021年 | 1241篇 |
2020年 | 752篇 |
2019年 | 1153篇 |
2018年 | 1312篇 |
2017年 | 955篇 |
2016年 | 1089篇 |
2015年 | 1130篇 |
2014年 | 1495篇 |
2013年 | 2154篇 |
2012年 | 3060篇 |
2011年 | 3317篇 |
2010年 | 1736篇 |
2009年 | 1473篇 |
2008年 | 2705篇 |
2007年 | 2721篇 |
2006年 | 2526篇 |
2005年 | 2343篇 |
2004年 | 2143篇 |
2003年 | 1866篇 |
2002年 | 1876篇 |
2001年 | 302篇 |
2000年 | 256篇 |
1999年 | 283篇 |
1998年 | 379篇 |
1997年 | 301篇 |
1996年 | 229篇 |
1995年 | 232篇 |
1994年 | 184篇 |
1993年 | 164篇 |
1992年 | 145篇 |
1991年 | 127篇 |
1990年 | 127篇 |
1989年 | 105篇 |
1988年 | 94篇 |
1987年 | 83篇 |
1986年 | 88篇 |
1985年 | 64篇 |
1984年 | 71篇 |
1983年 | 76篇 |
1982年 | 64篇 |
1981年 | 45篇 |
1980年 | 36篇 |
1979年 | 48篇 |
1978年 | 40篇 |
1974年 | 26篇 |
1972年 | 22篇 |
1970年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
111.
112.
113.
114.
115.
This study examined the influence of metamemory (i.e., self-report of memory ability and skills), in combination with other factors, on quality of life for people with multiple sclerosis (MS). Participants (482 persons with MS) completed instruments to measure functional limitations, depressive symptoms, metamemory, and perceived quality of life. Participants reported greater satisfaction with their memory performance but less frequent use of memory aids and strategies compared with 115 older adults on whom the instrument was originally tested. Components of metamemory were significantly related to neurological disability, duration of disease, depressive symptoms, age, and quality of life. Depressive symptoms had a higher impact than other variables in the final regression model on quality-of-life prediction. 相似文献
116.
117.
GM1 ganglioside is believed to be important in promoting the recovery of neurons from injury. The present study assesses the ability of GM1 to repair or prevent the damage of dopamine neurons caused by the neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Treatment of mesencephalic cell cultures with 2.5 μM MPP+ resulted in the loss of 30% of tyrosine hydoxylase (TH) immunoreactive neurons. In contrast, cultures administered 100 μM GM1 ganglioside for 3 days after toxin treatment contained nearly control numbers of TH+ neurons (97%). This reparative effect of GM1 was reflected in parallel increases in TH enzyme activity, dopamine and dopac levels. Cultures sustaining greater insult from higher doses of MPP+ (5.0–10.0 μM) did not benefit from ganglioside treatment, suggesting that rescue by GM1 depended on the degree of initial damage to cells. Moreover, the timing of ganglioside treatment was critical; pretreatment with GM1 alone did not prevent or attenuate the damage caused by subsequent incubation in 2.5 μM MPP+. 相似文献
118.
Anne Scupholme Jeanne DeJoseph Donna M. Strobino Lisa L. Paine 《Journal of Midwifery & Women's Health》1992,37(5):341-348
The purpose of this article is to describe the extent to which certified nurse-midwives (CNMs) provide care to vulnerable populations in the United States and the source of reimbursement for this care. The data were obtained from the first phase of a national study to address the characteristics of women served and cost of care provided by CNMs. Results were analyzed nationally and by American College of Nurse-Midwives regions. Certified nurse-midwives in all types of practices are providing care to women from populations that are vulnerable to poorer than average outcomes of childbirth because of age, socioeconomic status, refugee status, and ethnicity. Ninety-nine percent of CNMs report serving at least one group of vulnerable women, and CNMs in the inner city and rural practices serve several groups. The vast majority of CNMs are salaried; only 11% receive their primary income from fee-for-service. Fifty percent of the payment for CNM services is from Medicaid and government-subsidized sources whereas less than 20% comes from private insurance. Source of income varies by type of setting in which the CNM attends births. The results suggest that CNMs, as a group, make a major contribution to the care of vulnerable populations. 相似文献
119.
Alfred Heller Lisa Won Barbara Heller Philip C. Hoffmann 《Clinical and experimental pharmacology & physiology》1995,22(5):375-378
1. The rotation-mediated three-dimensional reaggregate culture system is uniquely suited for studies on developmental neurotoxicity. In this system, it is possible to reconstruct central neuronal pathways and follow their development. 2. Exposure to drugs of abuse including methamphetamine and methylenedioxyamphetamine or the appetite suppressant, fenfluramine, reduces monoamines in the cultures in a dose-dependent manner and interrupts normal monoaminergic development. 3. While the monoaminergic neurones may attain normal rates of development following drug removal, the affected neurones are not capable of overcoming the drug-induced insults and a deficiency in monoamines persists throughout development. 4. In addition, the production of immortalized monoclonal hybrid cells obtained by fusion of fetal mesencephalic neurones with a neuroblastoma has yielded cell lines expressing a dopaminergic phenotype. 5. Such cells have been useful in establishing the relationship of neurotoxicity to cell lineage and can serve as models for the study of the cellular and molecular mechanisms of neurotoxicity. 相似文献
120.
Accurate estimates of energy and nutrient intake of individuals and populations are contingent on the reliability of information obtained about food intake, food composition, and portion size. This article reviews issues related to the definition, determination, and use of portion sizes in dietary assessment and public education. 相似文献