全文获取类型
收费全文 | 83940篇 |
免费 | 6722篇 |
国内免费 | 4245篇 |
专业分类
耳鼻咽喉 | 791篇 |
儿科学 | 1519篇 |
妇产科学 | 1728篇 |
基础医学 | 11022篇 |
口腔科学 | 1226篇 |
临床医学 | 9618篇 |
内科学 | 14152篇 |
皮肤病学 | 1247篇 |
神经病学 | 5320篇 |
特种医学 | 2965篇 |
外国民族医学 | 52篇 |
外科学 | 9043篇 |
综合类 | 8540篇 |
现状与发展 | 19篇 |
一般理论 | 26篇 |
预防医学 | 7335篇 |
眼科学 | 2229篇 |
药学 | 7691篇 |
64篇 | |
中国医学 | 3146篇 |
肿瘤学 | 7174篇 |
出版年
2024年 | 207篇 |
2023年 | 1142篇 |
2022年 | 2746篇 |
2021年 | 3835篇 |
2020年 | 2560篇 |
2019年 | 2727篇 |
2018年 | 3012篇 |
2017年 | 2407篇 |
2016年 | 2437篇 |
2015年 | 3288篇 |
2014年 | 4129篇 |
2013年 | 4011篇 |
2012年 | 6243篇 |
2011年 | 6872篇 |
2010年 | 4008篇 |
2009年 | 3056篇 |
2008年 | 4560篇 |
2007年 | 4711篇 |
2006年 | 4592篇 |
2005年 | 4406篇 |
2004年 | 3315篇 |
2003年 | 3200篇 |
2002年 | 2742篇 |
2001年 | 1720篇 |
2000年 | 1807篇 |
1999年 | 1734篇 |
1998年 | 1048篇 |
1997年 | 995篇 |
1996年 | 767篇 |
1995年 | 696篇 |
1994年 | 587篇 |
1993年 | 385篇 |
1992年 | 578篇 |
1991年 | 517篇 |
1990年 | 494篇 |
1989年 | 461篇 |
1988年 | 438篇 |
1987年 | 382篇 |
1986年 | 345篇 |
1985年 | 285篇 |
1984年 | 204篇 |
1983年 | 161篇 |
1982年 | 83篇 |
1981年 | 87篇 |
1980年 | 69篇 |
1979年 | 143篇 |
1978年 | 61篇 |
1975年 | 72篇 |
1974年 | 73篇 |
1973年 | 53篇 |
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
1.
2.
Shengxuan Cao Chen Wang Xin Ma Xu Wang Jiazhang Huang Chao Zhang Li Chen Xiang Geng Kan Wang 《Journal of orthopaedic research》2019,37(8):1860-1867
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019 相似文献
3.
4.
Joseph M. Northey Kate L. Pumpa Clare Quinlan Ashley Ikin Kellie Toohey Disa J. Smee Ben Rattray 《Journal of Science and Medicine in Sport》2019,22(5):580-585
Objectives
The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.Design
Pilot randomised-controlled trial.Methods
Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.Results
All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.Conclusions
This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials. 相似文献5.
Objective
To explore from a gender perspective the association with subjective health of the interaction between education and household arrangements within the framework of social determinants of health placed at the micro and mezzo levels.Methods
The data comes from the Spanish sample of the European Union Statistics on Income and Living Conditions for 2014. Independent logistic regression models for men and women were run to analyze the association with subjective health of the interaction between education and household arrangements. An additive model was run to assess possible advantages over the interaction approach.Results
The interaction models show a lower or even no significant effect on health of household arrangements usually negatively associated with health among individuals with high education, displaying specific patterns according to sex.Conclusions
Health profiles of women and men are more precisely drawn if both social determinants of health are combined. Among the women, the important role was confirmed of both social determinants of health in understanding their health inequalities. Among the men, mainly those with low educational achievement, the interaction revealed that the household was a more meaningful social determinant of health. This could enable the definition of more efficient public policies to reduce health and gender inequalities. 相似文献6.
Background: Previous studies into leisure have employed methodologies that may understate the significance of experiential components. This exploratory study investigated the leisure experiences of retired Australians over 65 years of age.
Methods: Five semistructured interviews were used to explore the leisure experience of older people from metropolitan Adelaide. Data were coded and analysed thematically.
Results: Relaxation and engrossment emerged as commonly expressed experiences, yet were found to emerge as a result of engagement in occupations predefined as leisure. Experiences of freedom from both necessary duties and a sense of obligation were discussed as potential determinants of leisure consciousness.
Practice implications: This study highlights a need for therapists to actively access clients' subjective leisure experiences to enable engagement in personally meaningful leisure occupations. 相似文献
Methods: Five semistructured interviews were used to explore the leisure experience of older people from metropolitan Adelaide. Data were coded and analysed thematically.
Results: Relaxation and engrossment emerged as commonly expressed experiences, yet were found to emerge as a result of engagement in occupations predefined as leisure. Experiences of freedom from both necessary duties and a sense of obligation were discussed as potential determinants of leisure consciousness.
Practice implications: This study highlights a need for therapists to actively access clients' subjective leisure experiences to enable engagement in personally meaningful leisure occupations. 相似文献
7.
Effect of leptin on the regulation of placental hormone secretion in cultured human placental cells.
Raquel Coya Pedro Martul Jaime Algorta Ma Angeles Aniel-Quiroga Ma Angeles Busturia Rosa Se?arís 《Gynecological endocrinology》2006,22(11):620-626
Placenta is an important source of leptin during pregnancy that contributes to the high plasma leptin levels in pregnant women. Leptin and its functional receptors are synthesized in trophoblast cells that, in turn, secrete gestational hormones supporting a paracrine or autocrine role for leptin in the endocrine activity of the placenta. In the present study we examined the effect of leptin on in vitro release of gestational hormones (human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone, estrogens and testosterone) by human term placental cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Progesterone, hCG, hPL, estradiol, estrone, estriol and testosterone levels were measured by different assays in culture media of cells maintained in monolayer culture after incubation for 12, 24, 48 or 72 h with leptin or placebo. Incubation with leptin did not modify hCG, hPL, progesterone, estriol and estrone secretion for any of the doses and times assayed. However, leptin led to a dose-dependent decrease in estradiol release. This effect was observed when treatment with recombinant human leptin spanned from 12 to 72 h. At this time an increase in testosterone levels was observed in leptin-treated cells versus placebo. These results indicate that leptin can be considered a gestational hormone implied in the endocrine function of the placenta, with an important role in control of the production of steroid reproductive hormones in placental cells in vitro. 相似文献
8.
C Niek van Dijk Ben Willem J. Mol Liesbeth S. L. Lim Rene K. Marti Patrick M. M. Bossuyt 《Acta orthopaedica》1996,67(6):566-570
We prospectively enrolled 160 consecutive patients with inversion trauma of the ankle in a diagnostic protocol that included physical examination within 2 days and at 5 days after trauma, arthrography, stress radiography, and ultrasonography. 135 patients had pathological lateral ligament laxity on the later physical examination or lateral ligament rupture diagnosed on arthrography and they were operated on. 122 of these patients had ligament ruptures.
At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.
Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information. 相似文献
At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.
Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information. 相似文献
9.
10.
No impact of repeated endoscopic screens on gastric cancer mortality in a prospectively followed Chinese population at high risk. 总被引:6,自引:0,他引:6
B Riecken R Pfeiffer J L Ma M L Jin J Y Li W D Liu L Zhang Y S Chang M H Gail W C You 《Preventive medicine》2002,34(1):22-28
BACKGROUND: Gastric cancer (GC) is the leading cause of cancer deaths in China. Our study prospectively evaluated the impact of repeated endoscopic screens on GC mortality in a high-risk population in China. METHODS: Between 1989 and 1999, a population-based gastroscopic screening was conducted in 4,394 residents of Linqu County, China, a region with the highest rates of GC worldwide. Residents ages 35 to 64 years received initial gastroscopies with biopsies in 1989. Repeated endoscopies were performed in 1994 and 1999. Cancer occurrences and deaths were actively monitored throughout the entire period until July 2000. Mortality from GC was compared with expected values based on mortality rates obtained for Linqu in the 1990-1992 Chinese Cancer Mortality Survey. RESULTS: Between March 1989 and July 2000, 39,303 person-years were accumulated; 85 new GCs occurred, 29 (34.5%) were in early stage. Fifty-eight cases (68%) were identified at one of the screens. The number of observed deaths from GC (37) was close to the expected (36.8). The standardized mortality ratio was 1.01 (95% CI 0.72-1.37) for the entire cohort, 1.13 (95% CI 0.77-1.57) for males, and 0.65 (95% CI 0.26-1.32) for females. CONCLUSIONS: Despite high population coverage with repeated screens, no reduction in GC mortality was observed in this high-risk population in China. 相似文献