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101.
Göran K. Hansson Göran Bondjers Anders Bylock Lena Hjalmarsson 《Experimental and molecular pathology》1980,33(3):302-315
Immunoelectron microscopy with peroxidase-conjugated Fab fragments of anti-IgG was used for studying the localization of IgG in the aortic endothelium and subendothelial intima of atherosclerotic and nonatherosclerotic rabbits. Small amounts of IgG were found in the cell coat, in caveolae and vesicles, and also in intercellular clefts of endothelial cells from normocholesterolemic rabbits. Injured endothelial cells exhibited prominent accumulations of IgG in the cytoplasmic matrix, possibly due to leakage through plasma membrane defects. In atherosclerotic lesions from hypercholesterolemic rabbits, there was a striking increase in the amount of IgG-reactive material in the cell coat and vesicles of intact endothelial cells. Also in these animals, injured endothelial cells were characterized by a cytoplasmic IgG accumulation. There were prominent IgG depositions in the subendothelial zone of the lesions. IgG was adhering to collagen fibers, and also coating the surfaces of subendothelial foam cells. The pathophysiological significance of an interaction between such intimal IgG and phagocytes is discussed. 相似文献
102.
Jesper L. R. Andersson Anders Lilja P. Hartvig Bengt Långström Torsten Gordh Hermann Handwerker E. Torebjörk 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(2):192-199
Regional cerebral blood flow was measured with positron emission tomography (PET) in six healthy volunteers at rest and during
experimentally induced, sustained cutaneous pain on the dorsum of the right hand or on the dorsum of the right foot. Pain
was inflicted by intracutaneous injection of capsaicin, providing a mainly C-fibre nociceptive stimulus. Statistical analysis
showed significant activations along the central sulcus (SI) area when comparing pain in the hand to pain in the foot. Separate
comparison of both pain states to a baseline revealed different locations along the central sulcus for hand pain and foot
pain. The encountered differences are consistent with what is previously known about the somatotopics of non-painful stimuli.
When comparing painful stimuli to baseline, the contralateral anterior cingulate gyrus, the ipsilateral anterior insular cortex
and the ipsilateral prefrontal cortex were implicated. The results are consistent with an involvement of SI in the spatial
discrimination of acute cutaneous pain.
Received: 17 October 1996 / Accepted: 12 May 1997 相似文献
103.
Dan Sunnemark Sana Eltayeb Maria Nilsson Erik Wallstr?m Hans Lassmann Tomas Olsson Anna-Lena Berg Anders Ericsson-Dahlstrand 《Journal of neuroinflammation》2005,2(1):17
Background
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). It is associated with local activation of microglia and astroglia, infiltration of activated macrophages and T cells, active degradation of myelin and damage to axons and neurons. The proposed role for CX3CL1 (fractalkine) in the control of microglia activation and leukocyte infiltration places this chemokine and its receptor CX3CR1 in a potentially strategic position to control key aspects in the pathological events that are associated with development of brain lesions in MS. In this study, we examine this hypothesis by analyzing the distribution, kinetics, regulation and cellular origin of CX3CL1 and CX3CR1 mRNA expression in the CNS of rats with an experimentally induced MS-like disease, myelin oligodendrocyte glycoprotein (MOG)-induced autoimmune encephalomyelitis (EAE). 相似文献104.
Pinborg A Loft A Rasmussen S Schmidt L Langhoff-Roos J Greisen G Andersen AN 《Human reproduction (Oxford, England)》2004,19(2):435-441
BACKGROUND: In Denmark, one-third of twin pregnancies are the result of IVF/ICSI treatment. Limited data on neonatal outcome in IVF/ICSI twins are available in the literature. METHODS: A register study was conducted on neonatal morbidity and mortality in a complete national twin cohort including all 3438 (3393 live-born) IVF/ICSI and 10,362 (10,239 live-born) non-IVF/ICSI twins born between 1995 and 2000. Twins were identified in the National Medical Birth Registry and dichotomized into IVF/ICSI and non-IVF/ICSI by cross-reference with the Danish IVF Registry. Data on neonatal morbidity and mortality were retrieved from the Danish Patient Registry and the Danish Registry of Causes of Deaths. In order to exclude monozygotic twins, sub-analyses on unlike-sex twins were conducted. RESULTS: A birth weight discordance of >20% was observed in 20.6% of IVF/ICSI versus 15.7% of control twin pairs (P < 0.001). The risk of discordant birth weight >20% was OR 1.29 (95% CI 1.04-1.58) in unlike-sex IVF/ICSI twins versus control twins. The risk of delivery at <37 completed weeks and birth weight <2500 g was similar in the two cohorts; however, in unlike-sex IVF/ICSI versus control twins the risk of delivery at <37 weeks and birth weight <2500 g was OR 1.22 (95% CI 1.09-1.38) and OR 1.25 (1.11-1.40) respectively. After stratification for maternal age and parity, these risks disappeared. IVF/ICSI twins carried a higher risk of admittance to a neonatal intensive care unit (NICU) than control twins (OR 1.18, 95% CI 1.09-1.27), and this was even more pronounced in unlike-sex twins [OR 1.34 (95% CI 1.19-1.51)]. No differences were observed in malformation or mortality rates between the two cohorts. CONCLUSIONS: Despite higher birth weight discordance and more NICU admissions among IVF/ICSI twins, neonatal outcome in IVF/ICSI twins seems to be comparable with that of non-IVF/ICSI twins, when only dizygotic twins were considered in the comparisons. 相似文献
105.
Petrovsky N Kyvik KO Bonnevie-Nielsen V Beck-Nielsen H Green A Harrison LC 《Immunology》2002,106(4):584-589
Type 1 diabetes has been associated with an increased frequency of activated T cells and T-cell hyperactivity to non-specific and disease-specific stimuli including the islet autoantigen glutamic acid decarboxylase 65 (GAD). To address whether T-cell hyperactivity is genetic or acquired we measured whole blood cytokines in vitro in response to GAD or tetanus in 18 identical twin pairs, nine discordant for type 1 diabetes. In addition, the activity of 2', 5' oligoadenylate synthetase (OAS) in blood mononuclear cells was measured as a marker of viral infection. Interleukin-2 (IL-2) basally and IL-2 and interferon-gamma (IFN-gamma) in response to GAD, were detected more frequently and at higher levels in diabetic compared to non-diabetic twins. IL-10 was not different between groups. OAS activity was increased in diabetic compared to non-diabetic twins and showed a correlation with basal IL-2 and GAD-stimulated IFN-gamma and IL-10. These findings suggest that T-cell hyperactivity in type 1 diabetes is an acquired trait and could reflect persisting virus expression. 相似文献
106.
Extended voluntary running inhibits exercise-induced adult hippocampal progenitor proliferation in the spontaneously hypertensive rat 总被引:4,自引:0,他引:4
Naylor AS Persson AI Eriksson PS Jonsdottir IH Thorlin T 《Journal of neurophysiology》2005,93(5):2406-2414
Previous work has shown that voluntary running increases cell proliferation and neurogenesis in the dentate gyrus of the adult hippocampus. Here we report that long-term running for 24 days results in a down-regulation of hippocampal progenitor proliferation to one-half the level of nonrunning controls compared with a fivefold increase in progenitor proliferation seen after 9 days of voluntary running (short-term running). The negative effects seen on proliferation after 24 days of running were prevented by restricting daily running distances (by 30-50%) during 24 days. Long-term running for 24 days increases the response of the hypothalamic-pituitary-adrenal axis, with an increase in adrenal gland weight and increased plasma corticosterone levels, as well as decreased thymus weight, indicating a stress response as a possible mediator of decreased progenitor proliferation. Furthermore, the negative effects seen on the observed stress response after 24 days of running were prevented by restricting daily running distance. Short-term running did not alter these stress parameters compared with nonrunning controls. However, it increased phosphorylated cyclic AMP response element binding protein (pCREB) in the dentate gyrus, an increase that was not seen in nonrunning controls or after 24 days of running. Taken together, these data suggest that voluntary running does not always enhance proliferation and that the decrease in progenitor proliferation seen in long-term running is possibly mediated by mechanisms involving a stress response in the animal. However, a moderate level of long-term running was able to prevent the negative stress-related changes seen in unrestricted long-term running. 相似文献
107.
Sara Lustigman Robin F. Anders Graham V. Brown Ross L. Coppel 《Molecular and biochemical parasitology》1988,30(3)
Human antibodies affinity purified on an adsorbent prepared from a cDNA clone (Ag44) expressing a portion of a rhoptry antigen were used to characterize the synthesis and fate of the antigen in the asexual blood stages of Plasmodium falcipartum. The rhoptry antigen is synthesized in the mature trophozoite-stage parasites as a 103 kDa polypeptide, is present in the schizonts and merozoites as a 105 kDa polypeptide, is discharged from the rhoptries and found in the newly invaded red cells as a 110 kDa polypeptide. Anti-Ag44 antibodies immunoprecipitate the antigen and two additional polypeptides of 135 and 150 kDa from lysates of infected cells and from culture supernatants. The three polypeptides are associated in a non-covalent complex that persists in the newly invaded red cells. All the components of the high molecular weight rhoptry complex are antigenic and can be precipitated with immune human serum. The 135 kDa polypeptide is identical to a 140 kDa rhoptry antigen previously identified by a monoclonal antibody. 相似文献
108.
The authors developed a Web-based mission-based reporting (MBR) system for their university's (UC Davis's) health system to report faculty members' activities in research and creative work, clinical service, education, and community/university service. They developed the system over several years (1998-2001) in response to a perceived need to better define faculty members' productivity for faculty development, financial management, and program assessment. The goal was to create a measurement tool that could be used by department chairs to counsel faculty on their performances. The MBR system provides measures of effort for each of the university's four missions. Departments or the school can use the output to better define expenditures and allocations of resources. The system provides both a quantitative metric of times spent on various activities within each mission, and a qualitative metric for the effort expended. The authors report the process of developing the MBR system and making it applicable for both clinical and basic science departments, and the mixed success experienced in its implementation. The system appears to depict the activities of most faculty fairly accurately, and chairs of test departments have been generally enthusiastic. However, resistance to general implementation remains, chiefly due to concerns about reliability, validity, and time required for completing the report. The authors conclude that MBR can be useful but will require some streamlining and the elimination of other redundant reporting instruments. A well-defined purpose is required to motivate its use. 相似文献
109.
The Importance of Ventilation in Exercise-Induced Asthma 总被引:1,自引:0,他引:1
Allan Bundgaard Thorsten Ingemann-Hansen Anders Schmidt Jens Halkjaer-Kristensen Inge Bloch 《Allergy》1981,36(6):385-389
The degree of post treadmill-running decrease in pulmonary function (Exercise-Induced Asthma) in 11 adult asthmatics was compared with the decrease in pulmonary function followed by resting isocapnic hyperventilation. It was checked that ventilation during the hyperventilation was kept identical to the ventilation during treadmill-running by continuous recording of respiratory frequency, minute ventilation, tidal volume and accumulated ventilation. The temperature of the inspired air was identical in the two situations and the relative humidity was 40% during treadmill-running and 15% during hyperventilation. The average accumulated ventilation during treadmill-running and hyperventilation was 411 1/6 min in both events. The decrease in peak expiratory flow after treadmill-running was 25% and after isocapnic hyperventilation 24%. It is concluded that the ventilation is of more importance for the decrease in pulmonary function after exercise, than the work load. 相似文献
110.
Vidar Wendel-Hansen Michèle Rivière Masatsune Uno Irma Jansson Josiane Szpirer M. Quamrul Islam Göran Levan George Klein Junji Yodoi Anders Rosén Claude Szpirer 《Somatic Cell and Molecular Genetics》1990,16(3):283-286
Using Southern blot analysis of DNAs from human×rodent cell hybrids, we have mapped the CD23 leukocyte antigen gene (FCE2) to human chromosome 19. 相似文献