全文获取类型
收费全文 | 1888篇 |
免费 | 241篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 149篇 |
妇产科学 | 35篇 |
基础医学 | 284篇 |
口腔科学 | 10篇 |
临床医学 | 199篇 |
内科学 | 598篇 |
皮肤病学 | 15篇 |
神经病学 | 134篇 |
特种医学 | 56篇 |
外科学 | 164篇 |
综合类 | 71篇 |
一般理论 | 5篇 |
预防医学 | 190篇 |
眼科学 | 18篇 |
药学 | 153篇 |
中国医学 | 4篇 |
肿瘤学 | 49篇 |
出版年
2022年 | 17篇 |
2021年 | 38篇 |
2020年 | 22篇 |
2019年 | 18篇 |
2018年 | 28篇 |
2016年 | 29篇 |
2015年 | 24篇 |
2014年 | 39篇 |
2013年 | 45篇 |
2012年 | 57篇 |
2011年 | 76篇 |
2010年 | 53篇 |
2009年 | 37篇 |
2008年 | 85篇 |
2007年 | 86篇 |
2006年 | 83篇 |
2005年 | 67篇 |
2004年 | 67篇 |
2003年 | 68篇 |
2002年 | 79篇 |
2001年 | 74篇 |
2000年 | 68篇 |
1999年 | 59篇 |
1998年 | 38篇 |
1997年 | 25篇 |
1996年 | 33篇 |
1995年 | 34篇 |
1994年 | 24篇 |
1993年 | 25篇 |
1992年 | 54篇 |
1991年 | 39篇 |
1990年 | 33篇 |
1989年 | 35篇 |
1988年 | 33篇 |
1987年 | 39篇 |
1986年 | 26篇 |
1985年 | 34篇 |
1984年 | 34篇 |
1983年 | 20篇 |
1982年 | 18篇 |
1980年 | 19篇 |
1979年 | 39篇 |
1978年 | 32篇 |
1977年 | 30篇 |
1976年 | 20篇 |
1975年 | 20篇 |
1974年 | 27篇 |
1972年 | 26篇 |
1971年 | 23篇 |
1969年 | 24篇 |
排序方式: 共有2138条查询结果,搜索用时 15 毫秒
61.
Nittaya Phanuphak Nipat Teeratakulpisarn Frits van Griensven Nitiya Chomchey Suteeraporn Pinyakorn James LK Fletcher Rapee Trichavaroj Supanit Pattanachaiwit Nelson Michael Praphan Phanuphak Jerome H Kim Jintanat Ananworanich 《Journal of the International AIDS Society》2015,18(1)
Introduction
HIV transmission risk is highest during acute HIV infection (AHI). We evaluated HIV RNA in the anogenital compartment in men who have sex with men (MSM) during AHI and compared time to undetectable HIV RNA after three-drug versus five-drug antiretroviral therapy (ART) to understand risk for onward HIV transmission.Methods
MSM with AHI (n=54) had blood, seminal plasma and anal lavage collected for HIV RNA at baseline, days 3 and 7, and weeks 2, 4, 12 and 24. Data were compared between AHI stages: 1 (fourth-generation antigen-antibody combo immunoassay [IA]–, third-generation IA–, n=15), 2 (fourth-generation IA+, third-generation IA–, n=9) and 3 (fourth-generation IA+, third-generation IA+, western blot–/indeterminate, n=30) by randomization to five-drug (tenofovir+emtricitabine+efavirenz+raltegravir+maraviroc, n=18) versus three-drug (tenofovir+emtricitabine+efavirenz, n=18) regimens.Results
Mean age was 29 years and mean duration since HIV exposure was 15.4 days. Mean baseline HIV RNA was 5.5 in blood, 3.9 in seminal plasma and 2.6 log10 copies/ml in anal lavage (p<0.001). Blood and seminal plasma HIV RNA were higher in AHI Stage 3 compared to Stage 1 (p<0.01). Median time from ART initiation to HIV RNA <50 copies/ml was 60 days in blood, 15 days in seminal plasma and three days in anal lavage. Compared with the three-drug ART, the five-drug ART had a shorter time to HIV RNA <1500 copies/ml in blood (15 vs. 29 days, p=0.005) and <50 copies/ml in seminal plasma (13 vs. 24 days, p=0.048).Conclusions
Among MSM with AHI, HIV RNA was highest in blood, followed by seminal plasma and anal lavage. ART rapidly reduced HIV RNA in all compartments, with regimen intensified by raltegravir and maraviroc showing faster HIV RNA reductions in blood and seminal plasma. 相似文献62.
63.
P A Mawa J M Pickering G Miiro P B Namujju C Watera G Anyaegani J A G Whitworth A M Elliott 《The international journal of tuberculosis and lung disease》2004,8(5):586-592
OBJECTIVE: To determine whether tuberculin skin testing (TST) is associated with an increase in human immunodeficiency virus (HIV) viral load, and to examine the effect of TST on anti-mycobacterial immune responses. DESIGN: A nested cohort study of HIV-1-infected adults. METHOD: Forty-two participants (21 TST-positive and 21 TST-negative) from a larger cohort were recruited to the study. Blood was collected for CD4+ T-cell count, whole blood was cultured, and plasma saved for viral load. These measurements were taken before, 3 days after, 3 months after, and 3 months plus 3 days after TST. Cytokine responses to culture filtrate proteins (CFP) of Mycobacterium tuberculosis and phytohaemagglutinin (PHA) were examined in the whole blood assay. RESULTS: Twenty-nine participants attended all four visits. No statistically significant change in viral load, CD4+ T-cell count, or cytokine response to PHA was observed at any visit. However, TST was associated with a transient increase in the interferon-gamma response to CFP and a lasting increase in the interleukin-5 response to CFP. CONCLUSION: There appeared to be a systemic effect of TST on the anti-tuberculosis immune response. 相似文献
64.
Role of right ventricular endomyocardial biopsy in infants and children with suspected or possible myocarditis.
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
S A Webber G J Boyle R Jaffe R M Pickering L B Beerman F J Fricker 《Heart (British Cardiac Society)》1994,72(4):360-363
OBJECTIVES--To assess the diagnostic yield, sampling errors, risks, and therapeutic implications of right ventricular endomyocardial biopsy in children with suspected or possible myocarditis. DESIGN--Retrospective study. SETTING--Tertiary referral centre for paediatric cardiology, cardiac surgery, heart transplantation, and mechanical circulatory support. PATIENTS AND METHODS--Review of clinical and histological findings among 63 consecutive children with possible myocarditis undergoing right ventricular endomyocardial biopsy. Review of cardiac histology at subsequent necropsy or after explantation at time of transplantation. RESULTS--From January 1980 to December 1992, 76 biopsies were performed in 63 children (2 weeks to 18 years of age). In 41 cases, the biopsy was performed for evaluation of dilated cardiomyopathy. The median interval from onset of symptoms was one month. Eight children (20%; all with a history of less than six weeks duration) had biopsy proved myocarditis. Five of the eight children made a full recovery, including four who presented in cardiogenic shock. By contrast, only three of 33 children without evidence of myocarditis showed recovery of ventricular function. The whole heart was available for histological examination in 23 patients. Myocarditis was confirmed in one patient, and no evidence of myocarditis was found in the remaining 22 (all with negative biopsies). One procedure related death occurred in a 2 week old infant with dilated cardiomyopathy. In 22 cases, biopsy was performed for the evaluation of arrhythmia. Only one biopsy showed myocarditis. CONCLUSIONS--The diagnostic yield of a biopsy is low in children with arrhythmias. In children presenting with profound ventricular dysfunction, a diagnosis of acute myocarditis may avoid premature consideration of transplantation as this group has an important potential for full recovery. In less critically ill patients and in those with a longer duration of symptoms the justification for biopsy is not as clear and the procedure is not without risk. 相似文献
65.
66.
67.
68.
Robert Tanner Hagelstrom PhD MBA FACMG James Ford MD Gwendolyn M. Reiser MS LCG Marilu Nelson CGCM Diane L. Pickering MS Pamela A. Althof MS CGCM Peter F. Coccia MD 《Pediatric blood & cancer》2016,63(3):544-546
Male breast cancer (MBC) is unusual, especially in young adults. Most cases of MBC as a secondary malignancy relate to the previous treatment with ionizing radiation. MBC can be associated with mutations in hereditary cancer predisposition syndrome genes (i.e., BRCA2); however, no such association has been reported in patients with Cowden syndrome (involving the phosphatase and tensin homolog [PTEN] gene). We describe a patient with Cowden syndrome who was initially diagnosed with B‐cell lymphoblastic lymphoma at the age of 7 years, then MBC at the age of 31 years, and never received radiation therapy. 相似文献
69.
Clinical and patient‐reported outcomes of Chinese patients undergoing haemodialysis in hospital or in the community: A 1‐year longitudinal study
下载免费PDF全文
![点击此处可从《Nephrology (Carlton, Vic.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
70.
Gangwisch JE Heymsfield SB Boden-Albala B Buijs RM Kreier F Pickering TG Rundle AG Zammit GK Malaspina D 《Sleep》2007,30(12):1667-1673
STUDY OBJECTIVES: To explore the relationship between sleep duration and diabetes incidence over an 8- to 10-year follow-up period in data from the First National Health and Nutrition Examination Survey (NHANES I). We hypothesized that prolonged short sleep duration is associated with diabetes and that obesity and hypertension act as partial mediators of this relationship. The increased load on the pancreas from insulin resistance induced by chronically short sleep durations can, over time, compromise beta-cell function and lead to type 2 diabetes. No plausible mechanism has been identified by which long sleep duration could lead to diabetes. DESIGN: Multivariate longitudinal analyses of the NHANES I using logistic regression models. SETTING: Probability sample (n=8992) of the noninstitutionalized population of the United States between 1982 and 1992. PARTICIPANTS: Subjects between the ages of 32 and 86 years. MEASUREMENTS AND RESULTS: Between 1982 and 1992, 4.8% of the sample (n=430) were determined by physician diagnosis, hospital record, or cause of death to be incident cases of diabetes. Subjects with sleep durations of 5 or fewer hours (odds ratio = 1.47, 95% confidence interval 1.03-2.09) and subjects with sleep durations of 9 or more hours (odds ratio = 1.52, 95% confidence interval 1.06-2.18) were significantly more likely to have incident diabetes over the follow-up period after controlling for covariates. CONCLUSIONS: Short sleep duration could be a significant risk factor for diabetes. The association between long sleep duration and diabetes incidence is more likely to be due to some unmeasured confounder such as poor sleep quality. 相似文献