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排序方式: 共有8185条查询结果,搜索用时 15 毫秒
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Knopik VS Sparrow EP Madden PA Bucholz KK Hudziak JJ Reich W Slutske WS Grant JD McLaughlin TL Todorov A Todd RD Heath AC 《Psychological medicine》2005,35(5):625-635
BACKGROUND: Genetic influences have been shown to play a major role in determining the risk of attention-deficit hyperactivity disorder (ADHD). In addition, prenatal exposure to nicotine and/or alcohol has also been suggested to increase risk of the disorder. Little attention, however, has been directed to investigating the roles of genetic transmission and prenatal exposure simultaneously. METHOD: Diagnostic telephone interview data from parents of Missouri adolescent female twin pairs born during 1975-1985 were analyzed. Logistic regression models were fitted to interview data from a total of 1936 twin pairs (1091 MZ and 845 DZ pairs) to determine the relative contributions of parental smoking and drinking behavior (both during and outside of pregnancy) as risk factors for DSM-IV ADHD. Structural equation models were fitted to determine the extent of residual genetic and environmental influences on ADHD risk while controlling for effects of prenatal and parental predictors on risk. RESULTS: ADHD was more likely to be diagnosed in girls whose mothers or fathers were alcohol dependent, whose mothers reported heavy alcohol use during pregnancy, and in those with low birth weight. Controlling for other risk factors, risk was not significantly increased in those whose mothers smoked during pregnancy. After allowing for effects of prenatal and childhood predictors, 86% of the residual variance in ADHD risk was attributable to genetic effects and 14% to non-shared environmental influences. CONCLUSIONS: Prenatal and parental risk factors may not be important mediators of influences on risk with much of the association between these variables and ADHD appearing to be indirect. 相似文献
35.
An efficient SNP system for mouse genome scanning and elucidating strain relationships 总被引:8,自引:0,他引:8
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Petkov PM Ding Y Cassell MA Zhang W Wagner G Sargent EE Asquith S Crew V Johnson KA Robinson P Scott VE Wiles MV 《Genome research》2004,14(9):1806-1811
A set of 1638 informative SNP markers easily assayed by the Amplifluor genotyping system were tested in 102 mouse strains, including the majority of the common and wild-derived inbred strains available from The Jackson Laboratory. Selected from publicly available databases, the markers are on average ~1.5 Mb apart and, whenever possible, represent the rare allele in at least two strains. Amplifluor assays were developed for each marker and performed on two independent DNA samples from each strain. The mean number of polymorphisms between strains was 608±136 SD. Several tests indicate that the markers provide an effective system for performing genome scans and quantitative trait loci analyses in all but the most closely related strains. Additionally, the markers revealed several subtle differences between closely related mouse strains, including the groups of several 129, BALB, C3H, C57, and DBA strains, and a group of wild-derived inbred strains representing several Mus musculus subspecies. Applying a neighbor-joining method to the data, we constructed a mouse strain family tree, which in most cases confirmed existing genealogies. 相似文献
36.
Glucocorticoid inhibition of antigen-evoked histamine release from human skin 总被引:1,自引:0,他引:1
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![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Prednisolone causes a dose-related inhibition of antigen-evoked histamine release from IgE-sensitized human skin in vitro. The effective concentrations are of the same order as are achieved in plasma therapeutically.
Analysis of prednisolone inhibition shows that it acts on the second histamine release stage, antigen—antibody combination being unaffected.
In contrast with the traditional view, our results show that, at least in human skin, glucocorticoids can inhibit antigen-evoked histamine release.
相似文献37.
38.
Post-marketing surveillance of enalapril: experience in 11 710 hypertensive patients in general practice 总被引:1,自引:1,他引:1
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Warren D. Cooper David Sheldon Derek Brown Graham R. Kimber Valerie L. Isitt William J.C. Currie 《The British journal of general practice》1987,37(301):346-349
Post-marketing surveillance in general practice represents an important part of the monitoring of adverse events associated with newly introduced drugs. Such a study of the angiotensin-converting enzyme inhibitor enalapril maleate has been undertaken in 11 710 patients with essential hypertension. Serious adverse events occurred in 1.7% of patients, though most of these were not thought to be related to the treatment. The incidence rates of death (0.09%), stroke (0.11%) and myocardial infarction (0.15%) were compatible with rates predicted from age, sex and blood pressure considerations. Other events reported were hypotension (0.3%), angioneurotic oedema (0.03%), rash (0.5%), taste disturbance (0.2%) and cough (1.0%). The degree of blood pressure reduction attained was similar to that previously reported from pre-marketing development studies, as was the overall nature and frequency of both serious and non-serious adverse events. The most frequently reported event during enalapril therapy was of an improvement in well-being (19.8%). 相似文献
39.
William J. Engellenner Lloyd Rozboril Valerie P. Perdue Richard G. Burright Peter J. Donovick 《Physiology & behavior》1982,28(1):177-179
An inexpensive and easily constructed metabolic cage for mice is presented. This apparatus can reliably monitor food and fluid consumption, as well as urine and fecal output, in a relatively non-intrusive manner. 相似文献
40.
Bruce F. Pennington Shelley D. Smith Lon R. Cardon Javier Gayán Valerie S. Knopik Richard K. Olson John C. DeFries 《American journal of medical genetics. Part A》2002,114(3):260-268
Comorbidity is pervasive among both adult and child psychiatric disorders; however, the etiological mechanisms underlying the majority of comorbidities are unknown. This study used genetic linkage analysis to assess the etiology of comorbidity between reading disability (RD) and attention‐deficit hyperactivity disorder (ADHD), two common childhood disorders that frequently co‐occur. Sibling pairs (N = 85) were ascertained initially because at least one individual in each pair exhibited a history of reading difficulties. Univariate linkage analyses in sibling pairs selected for ADHD from within this RD‐ascertained sample suggested that a quantitative trait locus (QTL) on chromosome 6p is a susceptibility locus for ADHD. Because this QTL is in the same region as a well‐replicated QTL for reading disability, subsequent bivariate analyses were conducted to test if this QTL contributed to comorbidity between the two disorders. Analyses of data from sib pairs selected for reading deficits revealed suggestive bivariate linkage for ADHD and three measures of reading difficulty, indicating that comorbidity between RD and ADHD may be due at least in part to pleiotropic effects of a QTL on chromosome 6p. © 2002 Wiley‐Liss, Inc. 相似文献