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BG Schless H-P Müller M DeMelis A Pasquarelli SN Erné V Hombach 《Journal of medical engineering & technology》2013,37(2):56-60
Parameterization of the ST-segment is used as a tool for risk stratification for patients to suffer from ventricular tachycardia. This parameterization is performed in terms of Principal Component Analysis (PCA) applied on multichannel magnetocardiographic (MCG) recordings. 55-channel MCG was recorded from 14 normal persons, 10 patients with CHD, 14 patients with MI, and six patients with VT. We found a significantly (p?<?0.05) lower PCA-score in patients with MI compared to normals. The lowest PCA-score was found in VT patients. Significant differences can be found between VT patients and normals and also between VT patients and CHD patients. 相似文献
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Previous reports have described 5-20% prevalence of hyponatremia in extended care facilities, due largely to drugs or inappropriate antidiuretic hormone secretion. In our 400 bed VA extended care facility, 15 men with organic brain syndrome (Alzheimer's, multi-infarct dementia, anoxic encephalopathy or alcoholism) currently receive Isocal via gastrostomy as the sole source of nutrition. We noted intermittent hyponatremia in about half of these patients, and conducted a chart review to investigate the cause. Mean age was 68 yr (range 46-92); tube feeding duration was 3 mo.-3 yr; 266 Na concentrations were obtained from the charts. Simultaneous with these Na analyses, one of three diets prevailed: (A) mixed foods (3-6 g Na/day) orally before gastrostomy; (B) Isocal supplemented with NaCl to give 2 g Na/day; (C) unsupplemented Isocal providing 1 g Na/day. (B) and (C) had been randomly varied by rotating physicians. Serum Na was directly related to Na intake. On (A), Na was within normal range (135-145 mEq/l) in all men. One patient was hyponatremic during diet (B). During (C), eight patients were hyponatremic. Na was less than 135 mEq/l in 40% of all samples during diet (C) and less than 130 mEq/l in 14%. Changing from diet (A) or (B) to diet (C) caused nearly equivalent declines in Na and Cl; K and HCO-3 were unaffected. No hyponatremic patient took drugs known to cause hyponatremia, or had congestive heart failure, hypoalbuminemia, lipemia or fasting hyperglycemia. At the end of the study, four hyponatremic men were changed from (C) to (B); serum Na became normal in all four patients, without edema or hypertension.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Litten RZ Fertig JB Falk DE Ryan ML Mattson ME Collins JF Murtaugh C Ciraulo D Green AI Johnson B Pettinati H Swift R Afshar M Brunette MF Tiouririne NA Kampman K Stout R;NCIG Study Group 《Alcoholism, clinical and experimental research》2012,36(3):406-416
Background: Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol‐dependent population of very heavy drinkers. Methods: In this double‐blind, placebo‐controlled trial, 224 alcohol‐dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization. Results: No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy‐drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%). Conclusions: This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy‐drinking alcohol‐dependent patients. 相似文献
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Service-learning across an accelerated curriculum 总被引:1,自引:0,他引:1
Ward S Blair M Henton F Jackson H Landolt T Mattson K 《The Journal of nursing education》2007,46(9):427-430
In support of the community-based education philosophy, nursing faculty at a small health careers college in the midwestern United States incorporated a service-learning experience involving Sudanese refugee families and Latino community members into its accelerated community-based nursing program (ACE) curriculum. The purpose of the service-learning experience is to allow students the opportunity develop relationships through which they may gain an understanding of unique needs within a community. This article describes the development and benefits of the service-learning experience across the ACE curriculum. Through reflection, students broaden and deepen their understanding about the health of individuals in the community and acquire a more sophisticated understanding of risk 相似文献
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The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone. 相似文献