全文获取类型
收费全文 | 10480篇 |
免费 | 835篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 95篇 |
儿科学 | 402篇 |
妇产科学 | 286篇 |
基础医学 | 1410篇 |
口腔科学 | 143篇 |
临床医学 | 1303篇 |
内科学 | 1919篇 |
皮肤病学 | 139篇 |
神经病学 | 1076篇 |
特种医学 | 292篇 |
外科学 | 1109篇 |
综合类 | 110篇 |
一般理论 | 9篇 |
预防医学 | 1348篇 |
眼科学 | 210篇 |
药学 | 701篇 |
中国医学 | 5篇 |
肿瘤学 | 774篇 |
出版年
2023年 | 113篇 |
2022年 | 128篇 |
2021年 | 356篇 |
2020年 | 209篇 |
2019年 | 351篇 |
2018年 | 398篇 |
2017年 | 255篇 |
2016年 | 278篇 |
2015年 | 322篇 |
2014年 | 426篇 |
2013年 | 573篇 |
2012年 | 864篇 |
2011年 | 800篇 |
2010年 | 464篇 |
2009年 | 390篇 |
2008年 | 643篇 |
2007年 | 674篇 |
2006年 | 570篇 |
2005年 | 566篇 |
2004年 | 480篇 |
2003年 | 395篇 |
2002年 | 351篇 |
2001年 | 137篇 |
2000年 | 126篇 |
1999年 | 112篇 |
1998年 | 102篇 |
1997年 | 70篇 |
1996年 | 51篇 |
1995年 | 64篇 |
1994年 | 36篇 |
1993年 | 56篇 |
1992年 | 80篇 |
1991年 | 74篇 |
1990年 | 68篇 |
1989年 | 62篇 |
1988年 | 57篇 |
1987年 | 52篇 |
1986年 | 51篇 |
1985年 | 55篇 |
1984年 | 41篇 |
1983年 | 24篇 |
1981年 | 19篇 |
1979年 | 27篇 |
1978年 | 30篇 |
1976年 | 24篇 |
1973年 | 25篇 |
1972年 | 17篇 |
1970年 | 22篇 |
1969年 | 29篇 |
1968年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
961.
Jennifer L. Moran Emily T. Shifley John M. Levorse Shyamala Mani Kristin Ostmann Ariadna Perez‐Balaguer Dawn M. Walker Thomas F. Vogt Susan E. Cole 《Developmental dynamics》2009,238(7):1803-1812
Tight regulation of Notch pathway signaling is important in many aspects of embryonic development. Notch signaling can be modulated by expression of fringe genes, encoding glycosyltransferases that modify EGF repeats in the Notch receptor. Although Lunatic fringe (Lfng) has been shown to play important roles in vertebrate segmentation, comparatively little is known regarding the developmental functions of the other vertebrate fringe genes, Radical fringe (Rfng) and Manic fringe (Mfng). Here we report that Mfng expression is not required for embryonic development. Further, we find that despite significant overlap in expression patterns, we detect no obvious synergistic defects in mice in the absence of two, or all three, fringe genes during development of the axial skeleton, limbs, hindbrain, and cranial nerves. Developmental Dynamics 238:1803–1812, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
962.
Sherry L. Pagoto Andrea T. Kozak Priya John Jamie S. Bodenlos Donald Hedeker Bonnie Spring Kristin L. Schneider 《International journal of behavioral medicine》2009,16(4):316-322
Background
Intention-to-treat (ITT) is an analytic approach where all randomized participants are included in analyses and in their originally assigned condition, regardless of adherence or protocol deviation. 相似文献963.
964.
Conway de Macario E Macario AJ 《International journal of medical microbiology : IJMM》2009,299(2):99-108
Microbes that produce methane gas, methanogens, were identified as Archaea in the 1970s but their possible role in disease is only emerging now, after they were found in the large intestine, mouth, and vagina. Significant associations were observed, for instance, between levels of methanogens in periodontal pockets and severity of periodontitis, and between quantities of methanogens in the large intestine and diseases such as colon cancer and diverticulosis. Recently, a role for intestinal methanogens in obesity was proposed. The lesson learned is that for methanogens we have to look at their pathogenicity from a different angle in comparison to classic pathogens that invade tissues and release toxins. This type of pathogenicity has not yet been described for methanogens. Instead, methanogens seem to participate in pathogenicity indirectly, favoring the growth of other microbes, which are directly involved in pathogenesis. This indirect role should not be minimized. On the contrary, it has become clear that a fundamental change of approach to the understanding and control of microbial diseases must be implemented. A comprehensive strategy is needed to elucidate the syntrophic associations that are essential for a healthy relation among microbes (including methanogens) and between them and the host organism, and to unveil those associations that lead to disease. 相似文献
965.
A.H. El-Laboudi C. Etherington P. Whitaker I.J. Clifton S.P. Conway M. Denton D.G. Peckham 《Journal of cystic fibrosis》2009,8(4):273-275
IntroductionExtra-pulmonary complications of Burkholderia cepacia complex (Bcc) infection in patients with cystic fibrosis are unusual. To the best of the authors' knowledge no case of pyomyositis secondary to Bcc infection has been reported previously.Case presentationWe report a case of pyomyositis of the forearm caused by Bcc infection in a patient with CF. We also briefly discuss the management of pyomyositis.ConclusionPyomyositis is a potential extra-pulmonary complication of Bcc infection in patients with CF. A high index of clinical suspicion is required to make a prompt diagnosis. Final diagnosis may need MRI. An early diagnosis, aggressive medical therapy, multidisciplinary care and timely surgical intervention are all essential for proper management of this condition. 相似文献
966.
W. Charles Conway MD Mark B. Faries MD Michael B. Nicholl MD Alicia M. Terando MD Edwin C. Glass MD MyungShin Sim DrPH Donald L. Morton MD 《Annals of surgical oncology》2009,16(6):1548-1552
Background Age-related outcomes have become increasingly common in evaluating patients with melanoma. For instance, as age increases,
sentinel node (SN) nonidentification increases and SN positivity decreases. Furthermore, advanced age is a risk factor for
in-transit disease. We hypothesized that increasing age is accompanied by alterations in lymphatic function, possibly explaining
these findings.
Methods Our center’s melanoma database was queried to identify patients who underwent successful sentinel node biopsy after lymphoscintigraphy.
Records of those treated between 2000 and 2005 were reviewed for age, sex, drainage basin, intraoperative radioactivity, and
SN pathology.
Results The 858 patients had a mean age of 55 years; 59% were men. Mean radioactivity in the hottest SN was 5232 counts per second;
179 patients (21%) had SN metastases. SN count rates were significantly and inversely related to age (P < .001 by Pearson correlation, analysis of variance, and χ2 test). Mean counts per second were 6105, 5883, and 2720 for axillary, inguinal, and cervical basins, respectively (P < .01), and count rates in these basins were consistently lower with increasing age (neck and axilla, P < .001; groin, P = .060; Pearson correlation). Multivariate analysis confirmed an independent inverse association between age and count rates
(P < .001), overall and within each primary tumor site.
Conclusions Lymphatic function, as assessed by radiocolloid transit to and uptake within the SN, declines with age. Altered lymphatic
function in older patients may modify metastatic patterns; knowledge of this may help clarify findings of reduced nodal positivity
and increased in-transit disease in this population.
Presented in part at the International Sentinel Node Society Annual Meeting, Sydney, Australia, February 20, 2008. 相似文献
967.
968.
Further evidence for individual differences in placebo responding: an interactionist perspective 总被引:2,自引:0,他引:2
Geers AL Kosbab K Helfer SG Weiland PE Wellman JA 《Journal of psychosomatic research》2007,62(5):563-570
OBJECTIVE: A prior investigation found that individuals low in optimism are more likely to follow a negative placebo (nocebo) expectation. The present study tested the hypothesis that individuals high in optimism are more likely to follow a positive placebo expectation. METHODS: Individuals (N=56) varying in their level of optimism were randomly assigned to one of three conditions. In the first condition, participants were given the expectation that a placebo sleep treatment would improve their sleep quality (placebo expectation condition). In the second condition, participants engaged in the same sleep treatment activity but were not given the positive placebo expectation (treatment control condition). Finally, a third group did not receive the positive placebo expectation and also did not engage in the placebo sleep treatment (no-placebo control condition). RESULTS: Optimism was positively associated with better sleep quality in the placebo expectation condition (r=.48, P<.05). Optimism scores were not associated with better sleep quality in either the treatment control condition (r=-.17, P=.46) or the no-placebo control condition (r=-.24, P=.35). CONCLUSION: Dispositional optimism relates to placebo responding. This relationship, however, is not manifested in a simple increase or decrease in all types of placebo responding. Rather, it appears that, as optimism increases, response to the positive placebo expectation increases, whereas response to nocebo expectation decreases. It is recommended that future research on personality and placebo effects consider the interaction between situational and dispositional variables. 相似文献
969.
The effects of SMART Board technology, an interactive electronic whiteboard, and a 3s constant time delay (CTD) procedure
was evaluated for teaching sight word reading to students with moderate intellectual disabilties within a small group arrangment.
A multiple probe design across three word sets and replicated with three students was used to evaluate the effectiveness of
SMART Board technology on: (a) reading target grocery words; (b) matching grocery item photos to target grocery words; (c) reading other
students’ target grocery words through observational learning; and (d) matching grocery item photos to observational grocery
words. Results support use of this tool to teach multiple students at one time and its effects on observational learning of
non-target information. 相似文献
970.
Deficits in social functioning are potential risk factors for schizophrenia. Social functioning was assessed in 55 individuals "at risk" for schizophrenia, 16 first episode patients with schizophrenia and 45 normal comparison subjects. The Social Adjustment Inventory for Children and Adolescents (SAICA) was administered to adolescents <18 and the Social Adjustment Scale (SAS-SR) to young adults >17. The at risk and first episode groups significantly differed from the normal subjects on measures of social functioning in the domains of peer, family, work and school relationships. Individuals at risk for schizophrenia have significant functional deficits which may be potential indicators of increased vulnerability for psychosis. 相似文献