全文获取类型
收费全文 | 33949篇 |
免费 | 2702篇 |
国内免费 | 108篇 |
专业分类
耳鼻咽喉 | 268篇 |
儿科学 | 817篇 |
妇产科学 | 557篇 |
基础医学 | 4563篇 |
口腔科学 | 446篇 |
临床医学 | 3679篇 |
内科学 | 7426篇 |
皮肤病学 | 402篇 |
神经病学 | 2976篇 |
特种医学 | 1115篇 |
外科学 | 5832篇 |
综合类 | 480篇 |
现状与发展 | 1篇 |
一般理论 | 51篇 |
预防医学 | 2730篇 |
眼科学 | 475篇 |
药学 | 2328篇 |
中国医学 | 94篇 |
肿瘤学 | 2519篇 |
出版年
2023年 | 311篇 |
2022年 | 510篇 |
2021年 | 1118篇 |
2020年 | 630篇 |
2019年 | 979篇 |
2018年 | 1123篇 |
2017年 | 792篇 |
2016年 | 822篇 |
2015年 | 909篇 |
2014年 | 1268篇 |
2013年 | 1646篇 |
2012年 | 2586篇 |
2011年 | 2582篇 |
2010年 | 1388篇 |
2009年 | 1224篇 |
2008年 | 2084篇 |
2007年 | 2033篇 |
2006年 | 1851篇 |
2005年 | 1840篇 |
2004年 | 1727篇 |
2003年 | 1575篇 |
2002年 | 1541篇 |
2001年 | 414篇 |
2000年 | 395篇 |
1999年 | 416篇 |
1998年 | 332篇 |
1997年 | 277篇 |
1996年 | 252篇 |
1995年 | 227篇 |
1994年 | 241篇 |
1993年 | 196篇 |
1992年 | 235篇 |
1991年 | 226篇 |
1990年 | 198篇 |
1989年 | 172篇 |
1988年 | 194篇 |
1987年 | 235篇 |
1986年 | 200篇 |
1985年 | 171篇 |
1984年 | 162篇 |
1983年 | 139篇 |
1982年 | 131篇 |
1981年 | 119篇 |
1980年 | 131篇 |
1979年 | 117篇 |
1978年 | 101篇 |
1977年 | 99篇 |
1976年 | 71篇 |
1975年 | 77篇 |
1974年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
The purposes of the study were: (1) to evaluate the effects of different surfaces on the relationship between subtalar and knee joint function, and (2) to examine/explore alternative approaches to the evaluation of these relationships. Five subjects ran under four different surface conditions of various hardness, while both rear and sagittal view kinematic data were collected (200 Hz). Critical parameters describing the knee angle and rearfoot motion were examined in conjunction with a curve analysis technique which incorporated slope differences and curve correlations. A repeated measure ANOVA design (surface × subject) was used along with single subject procedures. The results of the study support a strong inter-relationship between pronation and knee joint function via tibial rotation and underlined it as a possible mechanism for injury. Moreover, discrete point analysis might not be the most appropriate methodology for evaluating dynamic functions such as rearfoot motion and knee angle. Extreme methodological care must be exercised when evaluating these functions to avoid oversmoothing and/or masking correlations and differences due to differential subject responses and individual variability. The fact that increased impact force facilitated timing discrepancies between subtalar and knee joint function resulting in a transition of the pronation curve from a unimodal to bimodal configuration, is hypothesized as a possible explanation to better understand the inter-relationships among these lower extremity functions and their relationship to running injuries. 相似文献
92.
93.
Nicholas J. Fox 《Sociology of health & illness》1994,16(1):1-18
The organization of daily procedures within the operating theatre is considered in terms of rival perspectives on their patient held by surgeon and anaesthetist. The privileging of the surgeon's authority is challenged in anaesthetists' efforts to fabricate a distinctive position on the patient. While surgeons focus on patient as the carrier of disease, for the anaesthetist, the focus is upon the patient's complement of fitness. A postmodern analysis of the organization of surgery reflects the continual struggle between the two specialisms to privilege its particular definition of the surgical patient. In some circumstances, the struggle can have damaging consequences for patient care. 相似文献
94.
An expression library was constructed by inserting cDNA copied from mRNA of the blood stages of Babesia bovis isolate KA into bacteriophage lambda gt11-amp3. An antigen-positive cDNA clone detected by screening the library with antibodies from cattle vaccinated with the KA isolate was shown to encode part of a high-molecular weight polypeptide antigen of B. bovis. This molecule was a dominant immunogen and was found by immunofluorescence to be within the parasite in infected erythrocytes. 相似文献
95.
96.
Vaccination of human volunteers with heat-killed M. leprae: local responses in relation to the interpretation of the lepromin reaction 总被引:1,自引:0,他引:1
H K Gill A S Mustafa T Godal 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1988,56(1):36-44
The early (Fernandez) and late (Mitsuda) lepromin reactions were closely examined in a group of healthy, BCG-vaccinated individuals who were given four doses of a heat-killed, armadillo-derived vaccine, i.e., 1.5 X 10(7), 5 X 10(7), 1.5 X 10(8), and 5 X 10(8) bacilli. There was a clear dose-response relationship for both the early and late reactions with no leveling of the responses within the range of doses examined. While the early response was negative in most of the volunteers, the late response was positive in all of the volunteers. No association was found between the early lepromin test and the pre-vaccination skin test to PPD. There was also no association between the early lepromin test and the pre-vaccination skin test response to a soluble Mycobacterium leprae antigenic preparation (MLSA) in general, but there was a good correlation between these two parameters at the highest vaccine dose. The late lepromin response showed no association with either the prevaccination or post-vaccination skin test response to PPD. However, there was a significant correlation between the late lepromin response and the post-vaccination skin test response to MLSA. In general, no association could be found between the in vivo skin tests and the in vitro lymphocyte transformation test (LTT). Thus, the lepromin test is essentially a vaccination which elicits a specific response to M. leprae antigens provided that the dose of armadillo lepromin given is higher than 5 X 10(7). Therefore, it is unsuitable as a diagnostic test for leprosy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
97.
Transformation of immortal, non-tumorigenic osteoblast-like human osteosarcoma cells to the tumorigenic phenotype by nickel sulfate 总被引:5,自引:2,他引:3
Rani A.Shobha; Qu Da-Qin; Sidhu Maninder K.; Panagakos Fotinos; Shah Varsha; Klein Kenneth M.; Brown Nicholas; Pathak Sen; Kumar Suriender 《Carcinogenesis》1993,14(5):947-953
Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS04 for 4896 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen. 相似文献
98.
99.
100.