全文获取类型
收费全文 | 2391篇 |
免费 | 158篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 174篇 |
妇产科学 | 35篇 |
基础医学 | 259篇 |
口腔科学 | 79篇 |
临床医学 | 230篇 |
内科学 | 508篇 |
皮肤病学 | 97篇 |
神经病学 | 64篇 |
特种医学 | 511篇 |
外科学 | 186篇 |
综合类 | 34篇 |
一般理论 | 1篇 |
预防医学 | 115篇 |
眼科学 | 19篇 |
药学 | 83篇 |
中国医学 | 5篇 |
肿瘤学 | 159篇 |
出版年
2022年 | 12篇 |
2021年 | 25篇 |
2020年 | 14篇 |
2019年 | 18篇 |
2018年 | 30篇 |
2017年 | 22篇 |
2016年 | 34篇 |
2015年 | 38篇 |
2014年 | 40篇 |
2013年 | 76篇 |
2012年 | 44篇 |
2011年 | 44篇 |
2010年 | 98篇 |
2009年 | 68篇 |
2008年 | 51篇 |
2007年 | 47篇 |
2006年 | 55篇 |
2005年 | 48篇 |
2004年 | 46篇 |
2003年 | 29篇 |
2002年 | 40篇 |
2001年 | 43篇 |
2000年 | 52篇 |
1999年 | 51篇 |
1998年 | 148篇 |
1997年 | 123篇 |
1996年 | 131篇 |
1995年 | 96篇 |
1994年 | 78篇 |
1993年 | 88篇 |
1992年 | 49篇 |
1991年 | 34篇 |
1990年 | 42篇 |
1989年 | 81篇 |
1988年 | 64篇 |
1987年 | 66篇 |
1986年 | 58篇 |
1985年 | 64篇 |
1984年 | 33篇 |
1983年 | 38篇 |
1982年 | 39篇 |
1981年 | 25篇 |
1980年 | 39篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 29篇 |
1976年 | 27篇 |
1975年 | 31篇 |
1974年 | 14篇 |
1969年 | 12篇 |
排序方式: 共有2572条查询结果,搜索用时 15 毫秒
1.
Mark Kantor PhD 《Journal of nutrition education and behavior》2006,38(1):349-69
2.
Aaron H. Burstein Pharm.D. William G. Reiss Pharm.D. Eric Kantor B.A. Gail D. Anderson Ph.D. 《Pharmacotherapy》1998,18(6):1271-1276
Study Objective . To characterize cytochrome P450 (CYP) 3A4 activity in premenopausal and postmenopausal women by evaluating the urinary 6-β-hydroxycortisokcortisol ratio. Design . Prospective study. Subjects . Thirteen premenopausal and 13 postmenopausal women who were healthy and not receiving drugs known to affect CYP3A4 activity. Interventions . Beginning on day 2 of menses, premenopausal women collected first morning urine samples every other day for a complete menstrual cycle. Postmenopausal women collected first morning urine every other day for 28 days. Measurements and Main Results . Mean weekly 6-β-hydroxycortisol:cortisol ratios did not differ during the phase (week) of the menstrual cycle. Daily ratios did not differ in postmenopausal women. No difference between premenopausal and postmenopausal women was found on comparing overall median ratios. Conclusion . Cytochrome P450 3A4 activity as measured by 6-β-hydroxy cortisol:cortisol ratio did not differ by week of menstrual cycle, suggesting no menstrual cycle-related changes. Menopause does not appear to be associated with differences in CYP3A4 activity, compared with premenopause. 相似文献
3.
J J de Souza T Perlmann A A Herman O J Ransome R W Kantor 《Suid-Afrikaanse tydskrif vir geneeskunde》1987,71(11):690-692
The value of maternal C-reactive protein (CRP) levels as predictors of fetal and maternal infective morbidity and fetal mortality was assessed prospectively over a 6-month period in all cases of premature rupture of the fetal membranes or suspected premature labour. Statistical analysis of results showed that CRP at a level of 1.32 mg/dl is a sensitive marker of infective morbidity in mother and neonate. Furthermore, there was a significant association between raised CRP levels and low-birth-weight babies, suggesting that intra-uterine infection is a major cause of prematurity in the study population. 相似文献
4.
JA HYEON KU CHEOL KWAK SEUNG-JUNE OH EUNSIK LEE SANG EUN LEE JAE-SEUNG PAICK 《International journal of urology》2004,11(7):489-493
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population. 相似文献
5.
Andrew M Briggs John D Wark Susan Kantor Rayson Teh Alison M Greig Nicola L Fazzalari Kim L Bennell 《Journal of clinical densitometry》2005,8(3):314-319
Analysis of apparent bone mineral density (BMD) in the lumbar spine is commonly based on anteroposterior (AP) scanning using dual-energy X-ray absorptiometry (DXA). Although not widely used, clinically important information can also be derived from lateral scanning. Vertebral bone density, and therefore strength, can may vary in different subregions of the vertebral body. Therefore, subregional BMD measurements might be informative about fracture risk. However, the intrarater and interrater precision of in vivo subregional BMD assessments from lateral DXA remains unknown. Ten normal, young (mean: 24 yr) and 10 older (mean: 63 yr) individuals with low BMD were scanned on one occasion using an AP/lateral sequence. Each lateral scan was reanalyzed six times at L2 by three raters to determine the intrarater and interrater precision in selecting seven regions of interest (subregions). Precision was expressed using percentage coefficients of variation (% CV) and intraclass correlation coefficients (ICC). Intrarater precision ranged from ICC(1,1) 0.971 to 0.996 (% CV: 0.50-3.68) for the young cohort and ICC(1,1) 0.934 to 0.993 (% CV: 1.46-5.30) for the older cohort. Interrater precision ranged from ICC(2,1) 0.804 to 0.915 (% CV: 1.11-2.35) for the young cohort and ICC(2,1) 0.912 to 0.984 (% CV: 1.85-4.32) for the older cohort. Scanning a subgroup of participants twice with repositioning was used to assess short-term in vivo precision. At L2, short-term in vivo precision ranged from ICC(1,1) 0.867 to 0.962 (% CV: 3.38-9.61), at L3 from ICC(1,1) 0.961 to 0.988 (% CV: 2.02-5.57) and using an L2/L3 combination from ICC(1,1) 0.942 to 0.980 (% CV: 2.04-4.61). This study demonstrated moderate to high precision for subregional analysis of apparent BMD in the lumbar spine using lateral DXA in vivo. 相似文献
6.
Pitfalls in diagnosis of aortic dissection by angiography: Algorithmic approach utilizing CT and MRI
Harold L. Mast David H. Gordon Alan M. Kantor 《Computerized medical imaging and graphics》1991,15(6):431-440
Dissection of the thoracic aorta is a life-threatening event requiring imaging studies to define the level of the tear and the intinmal flap. The “gold standard” has been angiography. This method may fail to demonstrate the dissection, however, due to overlap of the true and false lumens or a very thin flap that is imaged en face rather than tangentially. Computed tomography has a diagnostic accuracy of 95%, but can fail to image the dissection due to technical factors or a thrombosed false hunen. Magnetic resonance imaging requires a hemodynamically stable and cooperative patient. A diagnostic algorithm is proposed for diagnosis of aortic dissection based on renal function and the surgeon's imaging modality preference. 相似文献
7.
P Van Houtte M Roelandts D Devriendt M Minsat H Laharie G Kantor 《Cancer radiothérapie》2005,9(6-7):427-434
The authors present an update version of the indications for radiotherapy in the management of benign diseases. This is based on available randomized trials and recent international meetings. Validated indications remain the prevention of resected heterotopic bone ossifications, kelo?ds scars and pterygium and also treatment of arteriovenous malformations; the place of radiotherapy for malignant exophtalmia is more and more restricted. Randomized trials have demonstrated the efficacy of endobrachytherapy in the prevention of restenosis after angioplasty but the use of embedded stent has replaced this indication. Macular degeneration is no more an indication of radiotherapy. Quality requirements for radiotherapy are identical for benign or malignant indications. 相似文献
8.
9.
10.