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991.
Distal Proctocolitis and n-3 Polyunsaturated Fatty Acids (n-3 PUFAs): The Mucosal Effect In Situ 总被引:1,自引:0,他引:1
Almallah YZ Ewen SW El-Tahir A Mowat NA Brunt PW Sinclair TS Heys SD Eremin O 《Journal of clinical immunology》2000,20(1):68-76
It has been postulated that patients with ulcerative colitis (UC) have altered reactivity of gut-associated lymphoid tissue. In such cases there is intense infiltration of the mucosa with immune competent cells and associated tissue damage. We have shown previously that the dietary supplementation with the n-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) results in significant systemic immune suppression. The aim of this study, therefore, was to evaluate the in situ effect of n-3 PUFAs on distal proctocolitis. Each patient received either fish oil extract (EPA 3.2 g, DHA 2.4 g) (n = 9) or sunflower oil (n = 9) daily in a double blind manner for six months. Monthly assessment included: (1) disease activity using clinical, sigmoidoscopic, and histological scores and (2) immunohistochemical analysis (immunoglobulins, CD profiles) of rectal biopsy specimens (before and after six months supplementation) using monoclonal antibodies and quantitative computer-assisted video image analysis. Prior to receiving supplementation, patients with proctocolitis (n = 18) showed significantly higher numbers of cells expressing CD3 (pan T cells) and HLA-DR and IgM containing cells compared with non-colitic controls (n = 8). Six months supplementation with n-3 PUFAs resulted in significant reduction in the number of cells expressing CD3 and HLA and the percentage of cells containing IgM. There was no significant change in the CD20 nor the percentage of IgG or IgA containing cells in either group of patients with procto-colitis. In patients receiving n-3 PUFA supplementation, there was improvement in the disease activity and histological scores, compared with pretreatment evaluation. This study has demonstrated both evidence of suppression of in situ immune reactivity and concurrent reduction in disease activity in patients with proctocolitis receiving n-3 PUFA supplementation. This may have important implication for therapy in patients with ulcerative colitis. 相似文献
992.
993.
Paulo R. Dellani Martin Glaser Paulo R. Wille Goran Vucurevic Axel Stadie Thomas Bauermann Andrei Tropine Axel Perneczky Aldo von Wangenheim Peter Stoeter 《Journal of digital imaging》2007,20(1):88-97
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation. 相似文献
994.
Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis 下载免费PDF全文
Hoffmann N Rasmussen TB Jensen PØ Stub C Hentzer M Molin S Ciofu O Givskov M Johansen HK Høiby N 《Infection and immunity》2005,73(4):2504-2514
Pseudomonas aeruginosa causes a chronic infection in the lungs of cystic fibrosis (CF) patients by establishing an alginate-containing biofilm. The infection has been studied in several animal models; however, most of the models required artificial embedding of the bacteria. We present here a new pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF mice (Cftr(tmlUnc-/-)) and BALB/c mice, as reflected by the detection of a high number of P. aeruginosa organisms in the lung homogenates at 7 days postinfection and alginate biofilms, surrounded by polymorphonuclear leukocytes in the alveoli. In comparison, both an AHL-producing nonmucoid revertant (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore, the mouse model provides an improved method for evaluating the interaction between mucoid P. aeruginosa, the host, and antibacterial therapy. 相似文献
995.
Aboudola S Kotloff KL Kyne L Warny M Kelly EC Sougioultzis S Giannasca PJ Monath TP Kelly CP 《Infection and immunity》2003,71(3):1608-1610
There is a strong association between serum antibody responses to toxin A and protection against Clostridium difficile diarrhea. A parenteral C. difficile toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against C. difficile-associated diarrhea and colitis. 相似文献
996.
Microbial infections,immunomodulation, and drugs of abuse 总被引:12,自引:0,他引:12
The use of recreational drugs of abuse has generated serious health concerns. There is a long-recognized relationship between addictive drugs and increased levels of infections. Studies of the mechanisms of actions of these drugs became more urgent with the advent of AIDS and its correlation with abused substances. The nature and mechanisms of immunomodulation by marijuana, opiates, cocaine, nicotine, and alcohol are described in this review. Recent studies of the effects of opiates or marijuana on the immune system have demonstrated that they are receptor mediated, occurring both directly via specific receptors on immune cells and indirectly through similar receptors on cells of the nervous system. Findings are also discussed that demonstrate that cocaine and nicotine have similar immunomodulatory effects, which are also apparently receptor mediated. Finally, the nature and mechanisms of immunomodulation by alcohol are described. Although no specific alcohol receptors have been identified, it is widely recognized that alcohol enhances susceptibility to opportunistic microbes. The review covers recent studies of the effects of these drugs on immunity and on increased susceptibility to infectious diseases, including AIDS. 相似文献
997.
Detection and characterization of hepatitis C virus RNA in seminal plasma and spermatozoon fractions of semen from patients attempting medically assisted conception 下载免费PDF全文
998.
Requirement for tumor necrosis factor receptor 2 expression on vascular cells to induce experimental cerebral malaria 下载免费PDF全文
Stoelcker B Hehlgans T Weigl K Bluethmann H Grau GE Männel DN 《Infection and immunity》2002,70(10):5857-5859
Using tumor necrosis factor receptor type 2 (TNFR2)-deficient mice and generating bone marrow chimeras which express TNFR2 on either hematopoietic or nonhematopoietic cells, we demonstrated the requirement for TNFR2 expression on tissue cells to induce lethal cerebral malaria. Thus, TNFR2 on the brain vasculature mediates tumor necrosis factor-induced neurovascular lesions in experimental cerebral malaria. 相似文献
999.
Macaluso GM Graven-Nielsen T Svensson P 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,136(1):114-119
A heteronymous H reflex in the temporalis muscle can be elicited by selective stimulation of the masseteric nerve. The present study aimed at defining the optimal amplitude of the H reflex to detect inhibitory changes induced by stimulation of the perioral afferents and at providing new information on the control of masticatory muscles. Sixteen healthy volunteers participated in the experiment. A conditioning stimulus (CS) to the perioral skin was applied at various delays before an ipsilateral selective masseteric nerve stimulation (test stimulus: TS) while the subject was clenching the teeth at 25% of the maximal voluntary contraction. Two intensities of CS and TS were employed, high and low. The peak-to-peak amplitude of the H reflex (TS) and the root-mean-square value of the preceding electromyography were measured and the data analyzed by three-way analysis of variance and Tukey's posthoc tests. For both intensities used the heteronymous H reflex in the temporalis muscle was significantly decreased by prior activation of perioral afferents for delays from 5 to 60 ms. With a delay of 5 and 35 ms the preceding EMG level was not changed, while it was reduced at 20 and 60 ms delay. The intensities used to elicit the heteronymous H reflex of the temporalis muscle were appropriate to detect a reduction in motoneuron excitability. The reduction in the H reflex without a change in the preceding EMG at 5 and 35 ms delays could be due to presynaptic inhibition of the masseteric afferents exerted by the ipsilateral perioral afferents. 相似文献
1000.
An animal model of human-type memory loss based on aging, lesion, forebrain ischemia, and drug studies with the rat 总被引:2,自引:1,他引:2
The goals of this research were to develop a within-subject test of spatial working memory and performance for the rat in a T-maze, based on a delayed alternation, or "win-shift" foraging strategy. Using this model, specific aims were to compare the effects of: (1) age, (2) basal forebrain, medial septal, and amygdala lesions, (3) four vessel occlusion (4-VO), forebrain ischemia, and (4) physostigmine, scopolamine, arecoline, piracetam, and clonidine on memory and performance of young middle-aged, and old rats. Aging significantly impaired working memory and performance of Long-Evans rats. Memory of septal and basal forebrain, but not of amygdala lesioned rats was significantly impaired without effects on performance. Transient, 4-VO forebrain ischemia produced significant memory impairment, without effects on performance, and highly selective CA1 cell loss in the hippocampus. Physostigmine enhanced working memory in middle-aged and old rats. Scopolamine impaired memory in young, middle-aged, and old rats. Physostigmine reversed the scopolamine impairments of working memory. Arecoline enhanced memory in old rats without effects on performance. Piracetam and clonidine had no direct effects on memory, but piracetam increased and clonidine decreased speed of performance. From the aging, lesion, ischemia, and drug studies it was concluded that there was a convergence of evidence from 4 different approaches for a critical role for the hippocampus, particularly the CA1 fields, in spatial working memory. 相似文献