全文获取类型
收费全文 | 1723篇 |
免费 | 100篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 115篇 |
妇产科学 | 20篇 |
基础医学 | 346篇 |
口腔科学 | 39篇 |
临床医学 | 180篇 |
内科学 | 385篇 |
皮肤病学 | 8篇 |
神经病学 | 151篇 |
特种医学 | 68篇 |
外科学 | 168篇 |
综合类 | 17篇 |
预防医学 | 166篇 |
眼科学 | 17篇 |
药学 | 51篇 |
肿瘤学 | 84篇 |
出版年
2023年 | 7篇 |
2022年 | 32篇 |
2021年 | 35篇 |
2020年 | 27篇 |
2019年 | 25篇 |
2018年 | 18篇 |
2017年 | 39篇 |
2016年 | 35篇 |
2015年 | 48篇 |
2014年 | 54篇 |
2013年 | 77篇 |
2012年 | 123篇 |
2011年 | 125篇 |
2010年 | 55篇 |
2009年 | 68篇 |
2008年 | 131篇 |
2007年 | 117篇 |
2006年 | 136篇 |
2005年 | 86篇 |
2004年 | 104篇 |
2003年 | 123篇 |
2002年 | 102篇 |
2001年 | 25篇 |
2000年 | 8篇 |
1999年 | 21篇 |
1998年 | 24篇 |
1997年 | 13篇 |
1996年 | 8篇 |
1995年 | 15篇 |
1994年 | 11篇 |
1993年 | 7篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 11篇 |
1982年 | 7篇 |
1981年 | 10篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1977年 | 7篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1972年 | 5篇 |
1967年 | 3篇 |
排序方式: 共有1829条查询结果,搜索用时 15 毫秒
21.
Rissanen TT Korpisalo P Markkanen JE Liimatainen T Ordén MR Kholová I de Goede A Heikura T Gröhn OH Ylä-Herttuala S 《Circulation》2005,112(25):3937-3946
22.
Ungureanu D Vanhatupa S Kotaja N Yang J Aittomaki S Jänne OA Palvimo JJ Silvennoinen O 《Blood》2003,102(9):3311-3313
23.
Increased carotid atherosclerosis in andropausal middle-aged men 总被引:2,自引:0,他引:2
Mäkinen J Järvisalo MJ Pöllänen P Perheentupa A Irjala K Koskenvuo M Mäkinen J Huhtaniemi I Raitakari OT 《Journal of the American College of Cardiology》2005,45(10):1603-1608
OBJECTIVES: This study examined the association between carotid artery intima-media thickness (IMT), serum sex hormone levels, and andropausal symptoms in middle-aged men. BACKGROUND: Male sex hormones may play a dual role in the pathogenesis of atherosclerosis in men by carrying both proatherogenic and atheroprotective effects. METHODS: We studied 239 40- to 70-year-old men (mean +/- SD: 57 +/- 8 years) who participated in the Turku Aging Male Study and underwent serum lipid and sex hormone measurements. Ninety-nine men (age 58 +/- 7 years) were considered andropausal (i.e., serum testosterone <9.8 nmol/l or luteinizing hormone [LH] >6.0 U/l and testosterone in the normal range), and in both situations, they had subjective symptoms of andropause (a high symptom score in questionnaire). Three were excluded because of diabetes. The rest of the men (age 57 +/- 8 years) served as controls. Carotid IMT was determined using high-resolution B-mode ultrasound, and serum testosterone, estradiol (E2), LH, and sex hormone-binding globulin were measured using standard immunoassays. RESULTS: Andropausal men had a higher maximal IMT compared with controls in the common carotid (1.08 +/- 0.34 vs. 1.00 +/- 0.23, p < 0.05) and in the carotid bulb (1.44 +/- 0.48 vs. 1.27 +/- 0.35, p = 0.003). Common carotid IMT correlated inversely with serum testosterone (p = 0.003) and directly with LH (p = 0.006) in multivariate models adjusted for age, total cholesterol, body mass index, blood pressure, and smoking. CONCLUSIONS: Middle-aged men with symptoms of andropause, together with absolute or compensated (as reflected by high normal to elevated LH) testosterone deficiency, show increased carotid IMT. These data suggest that normal testosterone levels may offer protection against the development of atherosclerosis in middle-aged men. 相似文献
24.
Päivä H Laakso J Laine H Laaksonen R Knuuti J Raitakari OT 《Journal of the American College of Cardiology》2002,40(7):1241-1247
OBJECTIVE: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). METHODS: Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function.We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. RESULTS: Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). CONCLUSIONS: We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition. 相似文献
25.
26.
Tom Rosenström Markus Jokela Mirka Hintsanen Kim Josefsson Markus Juonala Mika Kivimäki Laura Pulkki-Råback Jorma S.A. Viikari Nina Hutri-Kähönen Erkki Heinonen Olli T. Raitakari Liisa Keltikangas-Järvinen 《Journal of affective disorders》2013
Background
Individual depressive symptoms may contribute to the risk of chronic depression. This study aimed to explore which symptoms predict chronic dysphoria, a hallmark of depression.Methods
1057 participants from the population-based Young Finns study were examined for four times during a 16-year period. Those with a modified Beck’s Depression Inventory score in the upper third at all four screenings were considered to have chronic dysphoria (n=135). Participants with only one high depression score formed the reference group of transient dysphoria (n=179). Individual items of the Inventory were analyzed in terms of their association with dysphoria status and chronicity, controlling for potential confounding factors, such as personality assessed using the Temperament and Character Inventory.Results
Body-image dissatisfaction was strongly associated with chronically elevated dysphoria (Bonferroni-corrected p=0.006). The degree of body-image dissatisfaction was associated with the probability for chronic dysphoria in a dose–response manner, with the estimated probability ranging from 0.01 to 0.60 as a function of item response. The association remained after adjustments for a wide range of personality characteristics.Limitations
The study relied on self-reports of mood and personality, and lacked information on external opinion on participants appearances. The requirement of full time-series data may have resulted in attrition-related bias.Conclusions
Body-image dissatisfaction was a strong predictor of chronic depression characterized by dysphoria. This finding suggests that dysfunctional attitude towards oneself might represent a potentially important target for cognitive therapies and preventive interventions. 相似文献27.
Boris Klempa Tatjana Avsic-Zupanc Jan Clement Tamara K. Dzagurova Heikki Henttonen Paul Heyman Ferenc Jakab Detlev H. Kruger Piet Maes Anna Papa Evgeniy A. Tkachenko Rainer G. Ulrich Olli Vapalahti Antti Vaheri 《Archives of virology》2013,158(3):521-529
Dobrava-Belgrade virus (DOBV) is a human pathogen that has evolved in, and is hosted by, mice of several species of the genus Apodemus. We propose a subdivision of the species Dobrava-Belgrade virus into four related genotypes – Dobrava, Kurkino, Saaremaa, and Sochi – that show characteristic differences in their phylogeny, specific host reservoirs, geographical distribution, and pathogenicity for humans. 相似文献
28.
29.
30.
Miia K. Laine Paula A. Tähtinen Olli Ruuskanen Eliisa Löyttyniemi Aino Ruohola 《Scandinavian journal of primary health care》2015,33(2):115-120
Objective. Scandinavian guidelines recommend controlling middle-ear effusion (MEE) after acute otitis media. The study aim was to determine whether nurses without otoscopic experience can reliably exclude MEE with tympanometry or spectral gradient acoustic reflectometry (SG-AR) at asymptomatic visits. Design. Three nurses were taught to perform examinations with tympanometry and SG-AR. Pneumatic otoscopy by the study physician served as the diagnostic standard. Setting. Study clinic at primary health care level. Patients. A total of 156 children aged 6–35 months. Main outcome measures. Predictive values (with 95% confidence interval) for tympanometry and SG-AR, and the clinical usefulness, i.e. the proportion of visits where nurses obtained the exclusive test result from both ears of the child. Results. At 196 visits, the negative predictive value of type A and C1 tympanograms (tympanometric peak pressure > −200 daPa) was 95% (91–97%). Based on type A and C1 tympanograms, the nurse could exclude MEE at 81/196 (41%) of visits. The negative predictive value of SG-AR level 1 result was 86% (79–91%). Based on SG-AR level 1 results, the nurse could exclude MEE at 29/196 (15%) of visits. Conclusion. Tympanograms with tympanometric peak pressure > −200 daPa (types A and C1) obtained by nurses are reliable test results in excluding MEE. However, these test results were obtained at less than half of the asymptomatic visits and, thus, the usefulness of excluding MEE by nurses depends on the clinical setting. 相似文献