全文获取类型
收费全文 | 104691篇 |
免费 | 29629篇 |
国内免费 | 1111篇 |
专业分类
耳鼻咽喉 | 2669篇 |
儿科学 | 2772篇 |
妇产科学 | 2520篇 |
基础医学 | 3494篇 |
口腔科学 | 5383篇 |
临床医学 | 26360篇 |
内科学 | 26139篇 |
皮肤病学 | 3401篇 |
神经病学 | 13120篇 |
特种医学 | 3756篇 |
外科学 | 18471篇 |
综合类 | 119篇 |
现状与发展 | 40篇 |
一般理论 | 5篇 |
预防医学 | 13635篇 |
眼科学 | 2192篇 |
药学 | 1530篇 |
中国医学 | 41篇 |
肿瘤学 | 9784篇 |
出版年
2024年 | 754篇 |
2023年 | 5099篇 |
2022年 | 1326篇 |
2021年 | 3033篇 |
2020年 | 5496篇 |
2019年 | 2210篇 |
2018年 | 7084篇 |
2017年 | 7517篇 |
2016年 | 8126篇 |
2015年 | 8236篇 |
2014年 | 10727篇 |
2013年 | 12458篇 |
2012年 | 4329篇 |
2011年 | 4169篇 |
2010年 | 7112篇 |
2009年 | 9348篇 |
2008年 | 3951篇 |
2007年 | 2803篇 |
2006年 | 3928篇 |
2005年 | 2509篇 |
2004年 | 1844篇 |
2003年 | 1505篇 |
2002年 | 1356篇 |
2001年 | 1864篇 |
2000年 | 1167篇 |
1999年 | 1720篇 |
1998年 | 2125篇 |
1997年 | 1939篇 |
1996年 | 1973篇 |
1995年 | 1720篇 |
1994年 | 1102篇 |
1993年 | 933篇 |
1992年 | 767篇 |
1991年 | 644篇 |
1990年 | 521篇 |
1989年 | 538篇 |
1988年 | 517篇 |
1987年 | 391篇 |
1986年 | 378篇 |
1985年 | 305篇 |
1984年 | 253篇 |
1983年 | 298篇 |
1982年 | 227篇 |
1981年 | 194篇 |
1980年 | 121篇 |
1978年 | 122篇 |
1977年 | 120篇 |
1976年 | 89篇 |
1974年 | 76篇 |
1972年 | 73篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
11.
12.
13.
The aim of this study was to design a new intravenous blood–gas exchange device and to estimate the design characteristics
of the device with a dimensionless function by using a substance that can be used instead of bovine blood. In addition, the
characteristics of oxygen transfer were estimated using empirical formulas and the reliability of the equations was ascertained
by comparing their output with an experiment performed using bovine blood. The dimensionless function was derived using distilled
water and bovine blood to estimate the oxygen transfer rate. Using the derived equations, the calculated oxygen transfer rates
for bovine blood and distilled water were similar for Reynolds numbers ranging from 0.7 to 7.0. Therefore, it is possible
to estimate the oxygen transfer rate in bovine blood, which is a non-Newtonian fluid, using distilled water, which is a Newtonian
fluid. Moreover, it was possible to verify the related equations because the oxygen transfer rate could be estimated using
the derived equations, according to the diameters of the various device modules. 相似文献
14.
15.
Edward R. Westrick MS Allan P. Shapiro PhD Peter E. Nathan PhD John Brick PhD 《Alcoholism, clinical and experimental research》1988,12(4):531-533
The present study demonstrates that alcohol-induced memory impairment can be attenuated by pretreatment with an oral tryptophan supplementation. These results provide support for the role of a brain serotonin deficit in this impairment and highlight the impact a dietary manipulation can have on a complex behavioral process. 相似文献
16.
17.
Eija Heikkinen MNSc RN Merja Nikkonen PhD RN & Helena Aavarinne PhD RN 《Journal of advanced nursing》1998,27(5):1069-1075
The definition of envy is commonly based on psychoanalytical views of organizational culture. The purpose of this paper is to describe envy in a nursing community. The population study consisted of random sample of 120 subjects drawn from among the employees of one central hospital in Finland. The study material consisted of data collected by questionnaires (response rate 65%). The data were processed by various statistical methods. Open-ended questions were analysed by inductive content analysis. The results of this study indicated that the employee's view of his/her official position in the nursing community, his/her relationships with his/her fellow workers and the management as well as relationships with other nursing communities are all related to envy. The employee's view of his/her official position intensified his/her feelings of envy, if he/she had other negative feelings, anxiety, dissatisfaction with him/herself, and negative feelings towards fellow workers. The major object of envy was fellow workers' salaries. Envy towards other nursing communities was generated by alleged differences in the amount of labour, or by the charge nurse's greater interest in other sections. Employees coped with envy by hiding these feelings and being modest. Women coped with envy by being silent, while men denied the value of the object of envy. 相似文献
18.
19.
Psychological Consequences of Food Restriction 总被引:1,自引:0,他引:1
JANET POLIVY PhD 《Journal of the American Dietetic Association》1996,96(6):589-592
A review of the literature and research on food restriction indicates that inhibiting food intake has consequences that may not have been anticipated by those attempting such restriction. Starvation and self-imposed dieting appear to result in eating binges once food is available and in psychological manifestations such as preoccupation with food and eating, increased emotional responsiveness and dysphoria, and distractibility. Caution is thus advisable in counseling clients to restrict their eating and diet to lose weight, as the negative sequelae may outweigh the benefits of restraining one's eating. Instead, healthful, balanced eating without specific food restrictions should be recommended as a long-term strategy to avoid the perils of restrictive dieting. J Am Diet Assoc. 1996; 96:589-592. 相似文献
20.
Peter Stone MD FRNZCOG FRCOG David Cook FRNZCOG MRCOG John Hutton PhD FRNZCOG FRCOG Gordon Purdie BSc Henry Murray MD FRNZCOG MRCOG Lauren Harcourt MPP BA 《The Australian & New Zealand journal of obstetrics & gynaecology》1995,35(1):32-37
Summary: This is the first report of the largest study of blood pressure measurement in pregnancy in a New Zealand population using standardized definitions and methodology. Over 3,800 women who delivered in an 8-month period in the Wellington region were included in the study. Blood pressure measurement and the presence of oedema and proteinuria were recorded from booking until delivery and in the puerperium. Only 2.7% of women were unable to be contacted after delivery for details on outcomes. The results established normal ranges for blood pressure throughout pregnancy. The data show that Mood pressure greater than 140/90 until 35 weeks' gestation is outside 2 standard deviations at all gestations and justifies using these measurements as the definition of hypertension in pregnancy. The fall in blood pressure in the 2nd trimester was less than 1 mm Ffg per week in both the systolic and diastolic pressures. This fall was smaller than previously recorded in other studies. Gestational hypertension was the commonest blood pressure abnormality occurring in 15.2% of the population. This represented 69% of the pregnant women with a hypertensive disorder. The overall incidence of both gestational hypertension and preeclampsia was 18.5% which is higher than reported in other parts of the world. In this study obesity was significantly associated with hypertensive disorders in pregnancy. An arm circumference of >33 cm, one of the measurements of obesity, was found in 6.8% of the study population. Even after the effect of arm circumference was taken into account, hypertensive disorders were also more common in Pacific Island women. Ankle oedema was significantly associated with the development of both gestational hypertension and preeclampsia but the incidence of oedema was noted in only 11.9% of the subjects. 相似文献