全文获取类型
收费全文 | 3964篇 |
免费 | 235篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 131篇 |
妇产科学 | 38篇 |
基础医学 | 480篇 |
口腔科学 | 46篇 |
临床医学 | 380篇 |
内科学 | 1058篇 |
皮肤病学 | 58篇 |
神经病学 | 440篇 |
特种医学 | 171篇 |
外科学 | 585篇 |
综合类 | 11篇 |
预防医学 | 258篇 |
眼科学 | 87篇 |
药学 | 213篇 |
中国医学 | 1篇 |
肿瘤学 | 235篇 |
出版年
2024年 | 3篇 |
2023年 | 32篇 |
2022年 | 42篇 |
2021年 | 135篇 |
2020年 | 90篇 |
2019年 | 118篇 |
2018年 | 130篇 |
2017年 | 111篇 |
2016年 | 105篇 |
2015年 | 111篇 |
2014年 | 150篇 |
2013年 | 233篇 |
2012年 | 367篇 |
2011年 | 359篇 |
2010年 | 184篇 |
2009年 | 187篇 |
2008年 | 256篇 |
2007年 | 271篇 |
2006年 | 278篇 |
2005年 | 241篇 |
2004年 | 216篇 |
2003年 | 191篇 |
2002年 | 153篇 |
2001年 | 26篇 |
2000年 | 26篇 |
1999年 | 25篇 |
1998年 | 21篇 |
1997年 | 26篇 |
1996年 | 17篇 |
1995年 | 21篇 |
1994年 | 13篇 |
1993年 | 14篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1964年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有4214条查询结果,搜索用时 15 毫秒
1.
Eric Racine Marie-Josée Dion Christine A. C. Wijman Judy Illes Maarten G. Lansberg 《Neurocritical care》2009,11(3):345-352
Background
Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability. 相似文献2.
Determinants of liver damage associated with intravenous methylprednisolone pulse therapy in Graves' ophthalmopathy. 总被引:3,自引:0,他引:3
Rosario Le Moli Lelio Baldeschi Peerooz Saeed Noortje Regensburg Maarten P Mourits Wilmar M Wiersinga 《Thyroid》2007,17(4):357-362
BACKGROUND: Intravenous methylprednisolone pulses (IVMP) are more efficacious and better tolerated than oral prednisone in Graves' ophthalmopathy (GO) patients. However, acute and severe liver damage has been reported in sporadic cases during IVMP, resulting in fatal acute liver failure in four patients so far. The mechanism causing the liver damage is incompletely understood. DESIGN: We performed a prospective observational study in 13 patients with dysthyroid optic neuropathy (group A) and in 14 patients with moderately severe GO (group B) who were treated with high-dose (group A) or low-dose (group B) IVMP; cumulative steroid doses were 8.45 g in group A and 4.5 g in group B, and follow-up time was 24 weeks. MAIN OUTCOME: Slight increases in serum aminotransferases (in alanine aminotransferase [ALAT] more than in aspartate aminotransferase [ASAT]) were observed, in seven patients exceeding the upper normal limit of 40 U/L. These changes were more prominent in group A than in group B as was also evident from a decrease in ASAT/ALAT ratio in group A but not in group B. Changes in serum aminotransferases occurred especially in the first 6 weeks of IVMP, becoming smaller thereafter with the decrease in steroid dosage. Pretreatment liver steatosis or diabetes were not related to liver damage, but preexistent viral hepatitis was. CONCLUSION: IVMP in GO patients causes dose-dependent liver damage by a direct toxic effect of glucocorticoids on hepatocytes. Nevertheless, IVMP seems to be pretty safe if cumulative doses exceeding 8 g are avoided and liver function is checked before and at regular intervals during pulse therapy. 相似文献
3.
Eva Maria Roes Maarten T M Raijmakers Wilbert H M Peters Eric A P Steegers 《Clinical chemistry and laboratory medicine》2002,40(5):496-498
Oral N-acetylcysteine supplementation in nine young healthy females induced a quick and highly significant decrease in plasma homocysteine levels and an increase in whole blood concentration of the antioxidant glutathione. N-acetylcysteine impresses as an efficient drug in lowering homocysteine concentration and might be beneficial for individuals with hyperhomocysteinemia who are at increased risk of cardiovascular disease. 相似文献
4.
Bradley R Pieters Johan N B van der Grient Leo E C M Blank Kees Koedooder Maarten C C M Hulshof Theo M de Reijke 《Radiotherapy and oncology》2006,80(1):69-72
Catheters were developed that can be fixed in the prostate gland by self-expanding parts for use in PDR brachytherapy. Daily CT-scans were made to investigate the magnitude of catheter displacement. The mean absolute displacement during the 3 day treatment was 1.2 mm. The resulting minor alterations in dose-volume parameters were of no clinical importance. 相似文献
5.
Michiel A. M. Feldberg M.D. Ph.D. Leon P. Driessen Theo D. Witkamp Maarten S. van Leeuwen Paul F. G. M. van Waes 《Urologic radiology》1988,10(1):92-94
In a case of diffuse xanthogranulomatous pyelonephritis, computed tomography (CT) and magnetic resonance (MR) were used. The MR proved to be more precise in the preoperative evaluation of inflammatory extension to the spleen and into the abdominal wall. The CT was more accurate in excluding spread to the colon. 相似文献
6.
Contralateral intrastriatal injection of 0.1 pmol or 1 pmol of endothelin-1 produced ipsilateral turning behaviour in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal pathway. This effect could be abolished by pretreatment with either the endothelinETA/B receptor antagonist bosentan (1 nmol, intrastriatally) or the dopamine D2 receptor antagonist raclopride (0.1 mg/kg, s.c.) suggesting that endothelin is acting at endothelin receptors to evoke ipsilateral turning behaviour and that this response is mediated by dopamine. Similar ipsilateral turning behaviour was observed upon intrastriatal injection of 1 pmol of endothelin-3 or the specific ETB receptor agonist, [Ala1,3,11,15]endothelin-1 when compared to endothelin-1. Pretreatment with the specific ETB receptor antagonist BQ788 blocked the ipsilateral turning response to intrastriatal injection of endothelin-1 while pretreatment with the specific ETA receptor antagonist BQ123 did not significantly change the response to injection of endothelin-1. This indicates that endothelin-1, which has affinity for both ETA and ETB receptors, is most likely acting at the ETB receptor to elicit its effect. These results suggest that low doses of endothelin may act at ETB receptors to evoke the release of dopamine from the striatum in vivo. 相似文献
7.
Snezana Kusljic David L Copolov Maarten van den Buuse 《Neuropsychopharmacology》2003,28(12):2138-2147
While an involvement of brain serotonin systems in schizophrenia has been suggested by many studies, the relative role of different serotonergic projections in the brain remains unclear. We therefore examined the effects of selective brain serotonin depletion on psychotropic drug-induced locomotor hyperactivity and prepulse inhibition, two animal models of aspects of schizophrenia. Pentobarbital-anesthetized (60 mg/kg, i.p.) male Sprague-Dawley rats were stereotaxically microinjected with 1 microl of a 5 microg/microl solution of the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) into either the dorsal or median raphe nucleus. At 2 weeks after the surgery, rats with dorsal raphe lesions did not show changes in psychotropic drug-induced locomotor hyperactivity, but displayed partial disruption of prepulse inhibition. In contrast, rats with median raphe lesions showed significant enhancement of phencyclidine-induced, but not amphetamine-induced locomotor hyperactivity and a marked disruption of prepulse inhibition. These results provide evidence for differential involvement of serotonergic projections in locomotor hyperactivity and prepulse inhibition. This study may help to explain the role of different serotonin projections in the brain in the pathophysiology of schizophrenia. 相似文献
8.
Michael Groeneweg Suzan Tan Annemieke M. Boot Johan C. de Jongste Jan Bouquet Maarten Sinaasappel 《Journal of cystic fibrosis》2002,1(4):583-280
BACKGROUND: Assessment of nutritional status in children with cystic fibrosis (CF) is clinically relevant. Methods to measure nutritional status should be reliable and non-invasive, and reference values should be available. AIM: To compare weight and height measurements and measurements of specific body compartments in children with CF. METHODS: In a cross-sectional survey of 58 children with CF (28 females), we compared height and weight (expressed as: weight-for-height, body mass index (BMI), height-for-age and weight-for-age) with fat mass (skinfold sum (SFS)), muscle mass (upper arm circumference (UAC)) and bioelectrical impedance analysis (BIA). Results were expressed as Z-scores, using Dutch reference values. RESULTS: BMI and weight-for-height were within the normal range (mean Z-score (range): -0.13 (-1.5, 2.7) and -0.02 (-1.7, 2.8)). Weight and height corrected for age were below normal (mean Z-score (range): -0.79 (-2.4, -0.05) and -1.2 (-2.8, 1.4) (P<0.01)). Lean body mass by skinfold sum (LBM(sfs)), UAC and BIA were also significantly below reference values (mean Z-score (range): -0.9 (-2.2, 1.8), -0.95 (-2.4, 1.8) and -1.1 (-3.6, 1.0) (P<0.01)). Lean body mass (LBM) by BIA correlated with LBM(sfs). BIA systematically underestimated LBM in both CF patients and in control subjects. CONCLUSION: Nutritional status of children with CF must be evaluated, using age-corrected weight and height expressed in Z-score. LBM estimated by SFS, UAC and by BIA appear to be useful, although longitudinal studies in CF children should be performed to evaluate their clinical significance in detecting changes in nutritional status. 相似文献
9.
Erik Diaz Teresa Gonzlez-Cossío Juan Rivera Maarten D. C. Immink Ruben Dario Mendoza C. Rafael Flores 《American journal of human biology》1991,3(5):525-530
This study aims at assessing the accuracy of estimates of body composition provided by bioimpedance (BIA) equations developed for U.S. populations when applied to a sample of Guatemalan farmers. If these equations were shown to have low validity, the second objective was to develop more accurate estimates of fat-free mass (FFM). One hundred males and females 19 to 45 years of age were randomly selected from four rural communities in the Western Highlands of Guatemala. Bioimpedance equations explained 59 and 33% of the variation in FFM, with a RMSE of 2.7 and 2.8 kg in males and females, respectively. Body fat (BF) predictions had a lower R2. Using the “all possible regressions” procedure, the best subset for prediction of FFM used anthropometric and BIA variables as predictors. The best model for men and women included only anthropometric variables: 75% of the variance in FFM for men and 70% of the variance in women was explained by this model. The RMSE was 2.1 and 1.9 kg for both groups, respectively. It is concluded that FFM can be estimated from anthropometric dimensions with a high degree of accuracy and use of BIA does not provide more valid estimates. 相似文献
10.
Wiegerinck MA Roukema M van Kessel PH Mol BW 《Human reproduction (Oxford, England)》2005,20(8):2355-2358
BACKGROUND: Sutureless re-anastomosis per laparoscopy is an alternative for microsurgical re-anastomosis by laparotomy in the treatment of sterilized women with renewed child wish. Our aim was to compare pregnancy rates after both surgical techniques. METHODS: We performed a retrospective cohort study in which consecutive women who underwent sutureless re-anastomosis per laparoscopy were compared to women who underwent microsurgical re-anastomosis by laparotomy. Both procedures were performed in neighbouring hospitals in Northern-Brabant, The Netherlands, and women were matched for age. The primary outcome was time to ongoing pregnancy. RESULTS: Overall, we included 41 women who had sutureless re-anastomosis by laparoscopy, and 41 age-matched women who underwent microsurgical re-anastomosis by laparotomy. The number of women who conceived was 20 (15 ongoing pregnancies) in the sutureless laparoscopic group versus 26 (24 ongoing pregnancies) in the laparotomic group, a difference due to a longer follow-up period in the laparotomic group. Time to ongoing pregnancy was comparable in both groups (P=0.46), with 3 year cumulative ongoing pregnancy rates of 45 and 52% respectively. After adjustment for other prognostic factors, the fecundity rate ratio was 0.97 (95% CI 0.26-3.6), indicating a similar performance of the two techniques. CONCLUSION: The simplified stitchless laparoscopic procedure for reversal of tubal sterilization with the use of a tubal splint, clip fixation of the muscularis and fibrin glue resulted in a promising pregnancy rate, which was similar to the pregnancy rate obtained with the microsurgical re-anastomosis per laparotomy. 相似文献