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61.
62.
OBJECTIVES: COPD is a common and disabling disease that entails high costs for society. The objectives of this study were to measure the societal costs of COPD in Sweden, and to examine the relationship between severity of illness and costs. METHODS: The costs of COPD were examined using a well-defined and representative cohort of subjects with mild, moderate, and severe COPD. Regular telephone interviews regarding resource utilization were made to a cohort of 212 subjects with COPD derived from studies of the general population in Northern Sweden. RESULTS: The annual per capita cost for COPD in Swedish crowns (SEK) was estimated at SEK 13,418 (1,284 US dollars (USD); 1,448 euros (EUR). The direct and indirect costs were SEK 5,592 (42%) and SEK 7,828 (58%), respectively. A highly significant relationship was found between severity of disease and costs. Costs for severe disease were 3 times as high as costs for moderate disease and > 10 times as high as for mild disease. Large individual variations in the level of costs were found. CONCLUSION: Assuming that the prevalence and treatment patterns are representative of Sweden as a whole, the total costs of COPD to society in 1999 were estimated at SEK 9.1 billion (USD 871 million; EUR 982 million). Subjects with mild disease (83%) accounted for 29%, while subjects with moderate disease (13%) accounted for 41% of the total costs. The subjects with severe disease (4%) accounted for the remainder (30%). Prevention, early diagnosis, and postponement of disease progression should have large monetary and policy implications. 相似文献
63.
Lars Nyberg Fredrik Magnussen Anders Lundquist William Baar David Bartrs-Faz Lars Bertram C. J. Boraxbekk Andreas M. Brandmaier Christian A. Drevon Klaus Ebmeier Paolo Ghisletta Richard N. Henson Carme Junqu Rogier Kievit Maike Kleemeyer Ethan Knights Simone Kühn Ulman Lindenberger Brenda W. J. H. Penninx Sara Pudas
ystein Srensen Lídia Vaqu-Alczar Kristine B. Walhovd Anders M. Fjell 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(18)
Education has been related to various advantageous lifetime outcomes. Here, using longitudinal structural MRI data (4,422 observations), we tested the influential hypothesis that higher education translates into slower rates of brain aging. Cross-sectionally, education was modestly associated with regional cortical volume. However, despite marked mean atrophy in the cortex and hippocampus, education did not influence rates of change. The results were replicated across two independent samples. Our findings challenge the view that higher education slows brain aging. 相似文献
64.
Intestinal barrier integrity and inflammatory bowel disease: Stem cell‐based approaches to regenerate the barrier 下载免费PDF全文
Fredrik E.O. Holmberg Jannie Pedersen Peter Jørgensen Christoffer Soendergaard Ole H. Nielsen 《Journal of tissue engineering and regenerative medicine》2018,12(4):923-935
Disruption of normal barrier function is a fundamental factor in the pathogenesis of inflammatory bowel disease, which includes increased epithelial cell death, modified mucus configuration, altered expression and distribution of tight junction proteins, along with a decreased expression of antimicrobial peptides. Inflammatory bowel disease is associated with life‐long morbidity for affected patients, and both the incidence and prevalence is increasing globally, resulting in substantial economic strain for society. Mucosal healing and re‐establishment of barrier integrity are associated with clinical remission, as well as with an improved patient outcome. Hence, these factors are vital treatment goals, which conventionally are achieved by a range of medical treatments, although none are effective in all patients, resulting in several patients still requiring surgery at some point. Therefore, novel treatment strategies to accomplish mucosal healing and to re‐establish normal barrier integrity in inflammatory bowel disease are warranted, and luminal stem cell‐based approaches might have an intriguing potential. Transplantation of in vitro expanded intestinal epithelial stem cells derived either directly from mucosal biopsies or from directed differentiation of human pluripotent stem cells may constitute complementary treatment options for patients with mucosal damage, as intestinal epithelial stem cells are multipotent and may give rise to all epithelial cell types of the intestine. This review provides the reader with a comprehensive state‐of‐the‐art overview of the intestinal barrier's role in healthy and diseased states, discussing the clinical application of stem cell‐based approaches to accomplish mucosal healing in inflammatory bowel disease. 相似文献
65.
Folic acid enhances endothelial function and reduces blood pressure in smokers: a randomized controlled trial 总被引:4,自引:0,他引:4
OBJECTIVE: Cigarette smoking is associated with increased plasma homocysteine concentrations, endothelial dysfunction and arterial stiffening. Homocysteine per se induces endothelial dysfunction and arterial stiffening and might account, at least partly, for the vascular abnormalities observed in smokers. We sought to determine whether folic acid supplementation, by reducing plasma homocysteine concentrations, enhanced endothelial function and reduced arterial stiffness in smokers. DESIGN: Double-blind, randomized controlled, parallel-group, trial. SETTING: Academic medical centre. SUBJECTS: A consecutive sample of 24 healthy cigarette smokers (age 37.8 +/- 2.5 years, mean +/- SEM). INTERVENTION: Subjects were randomly assigned to 4-week folic acid 5 mg day-1 or placebo. MAIN OUTCOME MEASURES: The following were measured before and after treatment: (i) peripheral vasoreactivity (forearm arterial blood flow, FABF) during intra-arterial administration of endothelium-dependent (acetylcholine 1.5, 4.5 and 15 microg min-1) and endothelium-independent (sodium nitroprusside 1, 2 and 4 microg min-1) vasodilators; (ii) carotid-femoral pulse-wave velocity (PWV); (iii) blood pressure (BP). RESULTS: Folic acid reduced homocysteine concentrations (10.8 +/- 0.6 vs. 8.2 +/- 0.5 micromol L-1, P < 0.001) and enhanced endothelium-dependent vasodilatation during each acetylcholine infusion rate (ratio between the FABF in the infused and control arm during increasing infusion rates at baseline 1.09 +/- 0.03 vs. 1.41 +/- 0.09 after treatment, P < 0.01; 1.39 +/- 0.07 vs. 1.83 +/- 0.12, P < 0.01; 1.65 +/- 0.16 vs. 2.72 +/- 0.36, P < 0.05) whilst endothelium-independent vasodilatation was unaffected. A significant fall in BP was also observed (mean BP 88 +/- 2 vs. 83 +/- 1 mmHg, P < 0.01). By contrast, PWV did not significantly change (8.4 +/- 0.3 vs. 7.8 +/- 0.4 m s-1). No significant changes in plasma homocysteine concentrations, FABF, BP, and PWV were observed in the placebo group. A multiple regression analysis showed that changes in folic acid plasma concentrations independently predicted both FABF changes during maximal acetylcholine-mediated vasodilatation (P < 0.01) and BP changes (P = 0.01). CONCLUSIONS: Short-term folic acid supplementation significantly enhanced endothelial function and reduced BP in young chronic smokers. These effects were largely independent from the homocysteine lowering effects. Thus, a simple, nontoxic, and relatively inexpensive vitamin intervention might be useful in primary cardiovascular prevention in this high-risk group. 相似文献
66.
Stimulation of polyamine biosynthesis by follicle-stimulating hormone in serum-free cultures of rat Sertoli cells 总被引:1,自引:0,他引:1
Sertoli cells derived from 21-day-old rats were cultured in serum-free Ham's F-10 medium to allow a direct investigation of the effects of FSH on polyamine (PA) biosynthesis in a defined culture system. After 48 h in culture, the basal cellular content consisted predominantly of spermine (1.1 nmol/mg protein) with substantially lower amounts of spermidine (0.1 nmol/mg protein) and undetectable amounts of putrescine. Upon the addition of ovine FSH (3 X 10(-9) M), cellular spermine content became significantly elevated above the control value as early as 1 h after treatment, reaching a 2.5-fold stimulation by 4 h. Spermidine was also elevated by 4 h after FSH treatment, but remained less than 20% of the spermine concentration. At no time did the cellular content of putrescine increase to measurable levels. Extended time-course studies demonstrated that the FSH-induced cellular increase in spermine and spermidine content persisted up to 24 h during the continuous presence of FSH. Bu2cAMP (5 mM) invoked similar changes in PA levels when measured at 4, 8, and 24 h. Ornithine decarboxylase (ODC) activity, which catalyzes the production of putrescine, was increased by FSH in a temporal fashion similar to that of spermine production. Addition of alpha-difluoromethylornithine, an irreversible inhibitor of ODC, blocked increases in both ODC activity and PA in cells stimulated with FSH or Bu2cAMP. Pulse-chase experiments using [3H]ornithine demonstrate that putrescine is initially synthesized, and is subsequently converted to spermidine and spermine. These studies suggest that regulation of PA biosynthesis by FSH is largely expressed as increases in spermine, and to a lesser extent spermidine, suggesting that the more complex PAs may be involved in the regulation of Sertoli cell function. 相似文献
67.
Atrial fibrillation signal organization predicts sinus rhythm maintenance in patients undergoing cardioversion of atrial fibrillation. 总被引:1,自引:0,他引:1
Fredrik Holmqvist Martin Stridh Johan E P Waktare Anders Roijer Leif S?rnmo Pyotr G Platonov Carl J Meurling 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(8):559-565
AIMS: Electrical remodelling is believed to influence the outcome following cardioversion of patients with persistent atrial fibrillation (AF). However, the results in clinical studies are conflicting. We assessed the hypothesis that non-invasively obtained atrial fibrillatory organization can be used as a predictor of sinus rhythm (SR) maintenance. METHODS AND RESULTS: Fifty-four patients (37 men, age 67+/-11) with persistent AF (median duration 3 months, 1 day to 18 months), without anti-arrhythmic drug treatment, referred for cardioversion were studied. Assessment of the atrial harmonic decay was made by time-frequency analysis of the ECG. At 1-month follow-up, 30 patients had relapsed into AF. The mean harmonic decay at inclusion of those relapsing into AF was 1.5+/-0.3 compared with 1.1+/-0.3 among those maintaining SR (P=0.0004). Using a cut-off value of harmonic decay 相似文献
68.
P C Swift J H Turner H F Oxer J P O'Shea G K Lane K V Woollard 《American heart journal》1992,124(5):1151-1158
To evaluate the potential for hyperbaric oxygen (HBO) to produce transient improvement in function in areas of myocardium ischemic at rest (hibernating myocardium), 24 patients were studied within 1 week of acute myocardial infarction. Results were compared with single-photon emission computed tomography (SPECT) thallium-201 exercise scintigraphy. Echocardiography demonstrated improved contraction following HBO in 20 of 62 damaged left ventricular segments in 12 of 24 patients. Thirteen of the 28 segments and 9 of the 14 patients showing reversible ischemia on SPECT imaging showed improvement with HBO. There were eight segments with apparently normal resting contraction that showed a reversible thallium defect. Of 42 segments with fixed contraction abnormalities following HBO, eight had reversible thallium defects, four had normal thallium kinetics, and 30 had fixed thallium defects. Thus hyperbaric oxygen can demonstrate improvement in function in some segments of left ventricle after infarction. There is some overlap with viability as determined by thallium studies, but the two techniques may be complementary in describing myocardial ischemia. 相似文献
69.
Aims/hypothesis Augmented formation of reactive oxygen species (ROS) induced by hyperglycaemia has been suggested to contribute to the development of diabetic nephropathy. This study was designed to evaluate the influence of streptozotocin (STZ)-induced diabetes mellitus, as well as the effects of preventing excessive ROS formation by -tocopherol treatment, on regional renal blood flow, oxygen tension and oxygen consumption in anaesthetized Wistar Furth rats.Methods Non-diabetic and STZ-diabetic rats were investigated after 4 weeks with or without dietary treatment with the radical scavenger DL--tocopherol (vitamin E, 5%). A laser-Doppler technique was used to measure regional renal blood flow, whilst oxygen tension and consumption were measured using Clark-type microelectrodes.Results Renal oxygen tension, but not renal blood flow, was lower throughout the renal parenchyma of diabetic rats when compared to non-diabetic control rats. The decrease in oxygen tension was most pronounced in the renal medulla. Renal cellular oxygen consumption was markedly increased in diabetic rats, predominantly in the medullary region. Diabetes increased lipid peroxidation and protein carbonylation in the renal medulla. Treatment with -tocopherol throughout the course of diabetes prevented diabetes-induced disturbances in oxidative stress, oxygen tension and consumption. The diabetic animals had a renal hypertrophy and a glomerular hyperfiltration, which were unaffected by -tocopherol treatment.Conclusions/interpretation We conclude that oxidative stress occurs in kidneys of diabetic rats predominantly in the medullary region and relates to augmented oxygen consumption and impaired oxygen tension in the tissue.Abbreviations ROS Reactive oxygen species - TBARS thiobarbituric acids reactive substances - NO nitric oxide - STZ streptozotocin 相似文献
70.
Supplementation of islet culture medium with insulin may have a beneficial effect on islet secretory function 总被引:2,自引:0,他引:2
Recent reports suggest that apoptosis resulting from the disruption of the normal cell-matrix relationship (anoikis) during islet isolation could lead to a loss of islet tissue in culture. Insulin is known to have a role in cell growth and survival, and this study was undertaken to assess any beneficial effect on islets by supplementing the islet culture medium with insulin. Human and porcine islets were cultured in medium supplemented with 0, 10, 100, and 1,000 ng x mL(-1) insulin. Secretory function was assessed by perifusion at days 1 and 8. The results demonstrated a significant variation in stimulation index between isolations for human islets, but there was no effect relating to the concentration of insulin in the medium or time in culture. For porcine islets, there was a significant (p < 0.001) improvement in secretory function for islets cultured in 10 and 100 ng x mL(-1) insulin, relative to 0 and 1,000 ng x mL(-1) insulin. There was no interisolation variation or effect of time in culture. In conclusion, the secretory function of porcine islets benefited from the addition of 10 to 100 ng x mL(-1) insulin to the culture medium, but interisolation variation in human islet secretory function did not allow any specific effect of the insulin to be determined. 相似文献