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341.
Lai PS Takeshima Y Adachi K Van Tran K Nguyen HT Low PS Matsuo M 《Journal of human genetics》2002,47(10):0552-0555
The frequency and distribution of deletions of 19 deletion-prone exons clustered in two hot spots in the proximal and central
regions of the dystrophin gene were compared in three populations from Singaporean, Japan, and Vietnam. DNA samples obtained
from 105 Singaporean, 86 Japanese, and 34 Vietnamese Duchenne muscular dystrophy patients were examined by polymerase chain
reaction amplification. Deletions of the examined exons were found in 51.2% of Japanese patients but in 40.0% or less of the
Singaporeans and Vietnamese. About two thirds of the deletions were localized in the central region and the remaining deletions
were clustered at the proximal region. The most commonly deleted exons at the central deletion hot spot were exon 50 in the
Singaporean, exons 49 and 50 in the Japanese, and exon 51 in the Vietnamese population. At the proximal deletion hot spot,
the most commonly deleted exons were exons 6 and 8 in the Singaporeans, exons 12 and 17 in the Japanese, and exons 8 and 12
in the Vietnamese. Two cases each from Singapore and Japan had large-scale gross mutations spanning both deletion hot spots.
Our results suggest that, although the presence and frequency of the two deletion hot spots may be similar in the three Asian
populations analyzed, the distribution and frequency of deletions among the different exons can vary as a result of population-specific
intronic sequences that predispose individuals to preferential deletion breakpoints.
Received: May 20, 2002 / Accepted: July 1, 2002 相似文献
342.
343.
Thomas M Morgan Lan Xiao Patrick Lyons Bethany Kassebaum Harlan M Krumholz John A Spertus 《BMC medical genetics》2008,9(1):66
Background
Many candidate genes have been reported to be risk factors for acute coronary syndrome (ACS), but their impact on clinical prognosis following ACS is unknown. 相似文献344.
Background
Statistics is relevant to students and practitioners in medicine and health sciences and is increasingly taught as part of the medical curriculum. However, it is common for students to dislike and under-perform in statistics. We sought to address these issues by redesigning the way that statistics is taught. 相似文献345.
Millar M 《Journal of behavioral medicine》2005,28(5):425-432
This study examined the impact of perceived stress on responses to messages that encouraged the performance of health promotion
and disease detection behaviors. It was hypothesized that increases in perceived stress would be associated with decreased
processing of messages encouraging disease detection behaviors, and that increases in perceived stress would not effect the
processing of messages encouraging health promotion behaviors. To test these hypotheses participants completed a perceived
stress measure and then read a message that encouraged the performance of either a health promotion or a disease detection
behavior. Then the participants were asked to indicate their agreement with the message and to attempt to recall the message.
The results indicated that participants experiencing higher levels of perceived stress spent less time reading and recalled
less of the messages about detection behaviors than of the messages about promotion behaviors. When participants were experiencing
lower levels of perceived stress these differences disappeared.
相似文献
相似文献
346.
We have known for some time that the epidemiology of human stroke is sexually dimorphic until late in life, well beyond the
years of reproductive senescence and menopause. Now, a new concept is emerging: the mechanisms and outcome of cerebral ischemic injury are influenced strongly by biological sex as well as the availability of sex steroids to the
brain. The principal mammalian estrogen (17 β estradiol or E2) is neuroprotective in many types of brain injury and has been
the major focus of investigation over the past several decades. However, it is becoming increasingly clear that although hormones
are a major contributor to sex-specific outcomes, they do not fully account for sex-specific responses to cerebral ischemia.
The purpose of this review is to highlight recent studies in cell culture and animal models that suggest that genetic sex
determines experimental stroke outcome and that divergent cell death pathways are activated after an ischemic insult. These
sex differences need to be identified if we are to develop efficacious neuroprotective agents for use in stroke patients. 相似文献
347.
Anthony J McGoron Michael Capille Michael F Georgiou Pablo Sanchez Juan Solano Manuel Gonzalez-Brito John W Kuluz 《BMC medical imaging》2008,8(1):4
Background
Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. 相似文献348.
Bruce R. Whiting Timothy A. Holden Barry S. Brunsden Charles C. Finley Margaret W. Skinner 《Journal of digital imaging》2008,21(3):323-328
While 3-dimensional (3D) imaging by computed tomography has long been desirable for research and treatment of cochlear-implant
patients, technical challenges have limited its wide application. Recent developments in scanner hardware and image processing
techniques now allow image quality improvements that make clinical applications feasible. Validation experiments were performed
to characterize a new methodology and its imaging performance. 相似文献
349.
Septins: a ring to part mother and daughter 总被引:15,自引:0,他引:15
The septins are well conserved GTPases found in animals and fungi. In yeast, they are required for the formation of 10-nm filaments, with which they co-localize at the bud neck. Therefore, septins have been proposed to be components of the neck filaments and to have polymerization properties. In support of this hypothesis, septin complexes purified from yeast and flies form filaments in vitro. However, recent studies have questioned the relevance of septin filament formation for septin function. Particularly, septin polymerization may not be required for their function in cytokinesis. New septin functions have also been recently uncovered: in budding yeast, the septin ring is required for the maintenance of cell polarity. It forms a cortical barrier that prevents lateral diffusion of membrane-associated proteins through the bud neck. Here, we review the most recent functional and biochemical data, to discuss whether there is a link between septin polymerization properties and septin function. 相似文献
350.