全文获取类型
收费全文 | 34958篇 |
免费 | 2648篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 334篇 |
儿科学 | 1043篇 |
妇产科学 | 903篇 |
基础医学 | 5344篇 |
口腔科学 | 472篇 |
临床医学 | 4990篇 |
内科学 | 6169篇 |
皮肤病学 | 701篇 |
神经病学 | 3910篇 |
特种医学 | 806篇 |
外科学 | 3177篇 |
综合类 | 276篇 |
现状与发展 | 1篇 |
一般理论 | 33篇 |
预防医学 | 3725篇 |
眼科学 | 606篇 |
药学 | 2285篇 |
中国医学 | 42篇 |
肿瘤学 | 2884篇 |
出版年
2024年 | 32篇 |
2023年 | 278篇 |
2022年 | 428篇 |
2021年 | 890篇 |
2020年 | 594篇 |
2019年 | 924篇 |
2018年 | 1099篇 |
2017年 | 855篇 |
2016年 | 938篇 |
2015年 | 971篇 |
2014年 | 1374篇 |
2013年 | 1772篇 |
2012年 | 2798篇 |
2011年 | 2882篇 |
2010年 | 1563篇 |
2009年 | 1419篇 |
2008年 | 2427篇 |
2007年 | 2498篇 |
2006年 | 2254篇 |
2005年 | 2351篇 |
2004年 | 2094篇 |
2003年 | 1954篇 |
2002年 | 1833篇 |
2001年 | 243篇 |
2000年 | 138篇 |
1999年 | 290篇 |
1998年 | 391篇 |
1997年 | 321篇 |
1996年 | 237篇 |
1995年 | 238篇 |
1994年 | 191篇 |
1993年 | 179篇 |
1992年 | 119篇 |
1991年 | 107篇 |
1990年 | 88篇 |
1989年 | 96篇 |
1988年 | 78篇 |
1987年 | 67篇 |
1986年 | 59篇 |
1985年 | 50篇 |
1984年 | 71篇 |
1983年 | 52篇 |
1982年 | 59篇 |
1981年 | 66篇 |
1980年 | 66篇 |
1979年 | 31篇 |
1978年 | 30篇 |
1977年 | 37篇 |
1976年 | 29篇 |
1974年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
Christine D. Dijkstra Corline J. A. De Groot Inge Huitinga 《Journal of neuroimmunology》1992,40(2-3):183-188
Experimental allergic encephalomyelitis (EAE) is an autoimmune inflammatory disease of the central nervous system (CNS). In particular in the CsA-induced chronic relapsing form (CREAE), pronounced demyelination occurs, in temporal association with relapses. It is still a matter of discussion which cell type ultimately is responsible for the actual process of demyelination. Macrophages, cytotoxic T lymphocytes and also astrocytes are possible candidates. In this short overview, the role of macrophages in the pathogenesis of EAE is discussed. It is shown that in particular, newly recruited macrophages play a crucial role in the generation of clinical signs. Possible mechanisms by which macrophages are involved in the pathogenesis of demyelinating diseases are presented. 相似文献
72.
73.
Dr. Gerold Wetscher MD Elizabeth Redmond MD Christine Watfah MD Galen Perdikis MD Michael Gadenstätter MD Rudolph Pointner MD 《Digestive diseases and sciences》1994,39(12):2511-2515
Bone disorders following gastrectomy were studied by measuring absolute and relative bone mineral density of the Wards triangle, serum 1,25-(OH)2-D, alkaline phosphatase, and total serum calcium. The subjects were 20 males who had undergone total gastrectomy not more than three months previously (group A1). Seventeen of these patients were reviewed three years later (group A2). Absolute and relative bone density were significantly lower in group A2 than in A1 (0.52 ± 0.011 g/cm2 versus 0.6 ± 0.014 g/cm2,P<0.01 and 85.5 ± 1.4% age-matched control versus 95 ± 1.3%,P<0.01). 1,25-(OH)2-D was significantly lower in group A2 than in group A1 (14.3 ± 0.97 pg/ml versus 20.6 ± 1.02 pg/ml,P<0.01). There was no difference in alkaline phosphatase and calcium serum concentration. The mean weight loss was 6.26 ± 0.57% over the follow-up period, and weight loss correlated with absolute and relative bone density (r=–0.74,P<0.01). There was a positive correlation between 1,25-(OH)2-D and absolute or relative bone density (r=0.67,r=0.62 andP<0.01). These data suggest that bone density decrease has already occurred three years after total gastrectomy and is positively correlated to 1,25-(OH)2-D deficiency. As no differences in serum alkaline phosphatase and serum calcium concentration were found, these factors are of little value for the early detection of postgastrectomy bone disorders, whereas weight loss is a valuable screening parameter. 相似文献
74.
Christine B Ambrosone Mary K Nesline Warren Davis 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1575-1577
The establishment of a biorepository with linkage to clinical and epidemiologic data will provide an invaluable resource for cancer research, including studies of cancer etiology, progression, and prognosis, as well as development of biomarkers for early detection. Developing an infrastructure for a biorepository linked to clinical, pathologic, and epidemiologic data requires significant efforts in strategic planning for efficient means to ascertain, identify, and consent participants, as well as guidelines for blood collection, processing, and storage while maintaining participant privacy rights. In this report, we present an approach to developing a Data Bank and Biorepository at our own institution, with discussion of elements to be considered when establishing such a bank. 相似文献
75.
76.
77.
The Changing Faces of the Nutcracker Esophagus 总被引:3,自引:0,他引:3
Christine B. Dalton P.A.C. Donald O. Castell M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1988,83(6):623-628
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed. 相似文献
78.
Christine Liddell Gordon Rae Tom R M Brown David Johnston Vivien Coates John Mallett 《The British journal of general practice》2004,54(506):667-672
BACKGROUND: Providing patients with an audiotape of their medical consultation has been a relatively common practice in oncology clinics for some years. However, broader generalisability of the technique has yet to be examined. AIMS: To investigate the efficacy of providing patients with an audiotape of their consultation in a general practice setting. DESIGN OF STUDY: Randomised controlled trial: 95 experimental participants, 85 controls. SETTING: Routine surgeries run by two general practitioners (GPs) in two different health centres. METHOD: All patients attending GP appointments were eligible for inclusion. Patients were followed up by telephone 7-10 days later. RESULTS: More than half (61%) of the patients who received a tape listened to it. Among listeners, 64% rated the tape useful or very useful; 24% noticed information not heard in the consultation. Half of listeners (46%) said that their understanding of the consultation improved after listening to the tape. Half of the listeners (48%) shared the tape with others, of whom 71% found sharing helpful or very helpful. However, 21% of those who shared the information with others found this unhelpful or very unhelpful, suggesting that patients may need to be briefed on the potential risks of sharing. At follow-up a week later, it emerged that being given a tape had no effect on adherence with GPs' advice, nor on anxiety about conditions. CONCLUSION: Providing patients with an audiotape of their GP consultation was positively rated by many patients. Although there were no detectable clinical effects at follow-up, the technique merits further evaluation in general practice. 相似文献
79.
80.
Thomas F Campbell Christine Dollaghan Janine E Janosky P David Adelson 《J. Speech Lang. Hear. Res.》2007,50(4):1110-1119
PURPOSE: Interpreting the rapidly changing speech skills of young children recovering from neurological injury is difficult because developmental expectations are generally available only at relatively lengthy intervals (e.g., 6 or 12 months). In this research note, the authors describe the process of generating a Percentage of Consonants Correct-Revised (PCC-R; L. D. Shriberg, D. Austin, B. A. Lewis, J. L. McSweeny, & D. L. Wilson, 1997a) performance curve and illustrate some of its applications for assessing change in performance over time. METHOD: The authors compiled mean PCC-R scores from 16 samples of typically developing children (18-172 months) and used curve fitting to test more than 11,000 statistical models of monthly growth in PCC-R. They selected a parsimonious and developmentally plausible model with R(2) = .9839 (p < .0005) and used it to generate the PCC-R, standard deviation, and standard error expected at each monthly age. RESULTS: The PCC-R performance curve distinguished among 65 children (37-57 months of age) diagnosed independently with normal or disordered speech with a high degree of success. More important, the PCC-R performance curve can be used to identify the points at which children (18-172 months) recovering from neurological injury achieve normal-range consonant production. CONCLUSION: The curve-fitting approach holds promise as a means of interpreting temporal variations in speech production at a finer grain than existing normative data currently allow. 相似文献