全文获取类型
收费全文 | 3636篇 |
免费 | 208篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 92篇 |
妇产科学 | 90篇 |
基础医学 | 384篇 |
口腔科学 | 52篇 |
临床医学 | 505篇 |
内科学 | 539篇 |
皮肤病学 | 76篇 |
神经病学 | 262篇 |
特种医学 | 93篇 |
外科学 | 500篇 |
综合类 | 49篇 |
一般理论 | 4篇 |
预防医学 | 546篇 |
眼科学 | 134篇 |
药学 | 278篇 |
中国医学 | 3篇 |
肿瘤学 | 226篇 |
出版年
2023年 | 33篇 |
2022年 | 55篇 |
2021年 | 93篇 |
2020年 | 50篇 |
2019年 | 91篇 |
2018年 | 85篇 |
2017年 | 78篇 |
2016年 | 79篇 |
2015年 | 93篇 |
2014年 | 128篇 |
2013年 | 170篇 |
2012年 | 286篇 |
2011年 | 295篇 |
2010年 | 156篇 |
2009年 | 120篇 |
2008年 | 224篇 |
2007年 | 230篇 |
2006年 | 228篇 |
2005年 | 235篇 |
2004年 | 202篇 |
2003年 | 192篇 |
2002年 | 157篇 |
2001年 | 45篇 |
2000年 | 39篇 |
1999年 | 37篇 |
1998年 | 31篇 |
1997年 | 24篇 |
1996年 | 23篇 |
1995年 | 24篇 |
1994年 | 17篇 |
1993年 | 11篇 |
1992年 | 25篇 |
1991年 | 33篇 |
1990年 | 27篇 |
1989年 | 20篇 |
1988年 | 14篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 13篇 |
1984年 | 16篇 |
1983年 | 12篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1976年 | 7篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1973年 | 10篇 |
1972年 | 7篇 |
1971年 | 12篇 |
1970年 | 8篇 |
排序方式: 共有3849条查询结果,搜索用时 15 毫秒
61.
E H Shao V Sivagnanavel A Dabbagh R Dave S Tempest-Roe F W K Tam S R Taylor 《Eye (London, England)》2015,29(4):569-573
Purpose
To investigate whether intravitreal ranibizumab injections administered to a child alter systemic plasma levels of total and free VEGF 165.Methods
A 9-year-old child sustained a choroidal rupture from blunt trauma. He subsequently developed a secondary choroidal neovascular membrane, which was treated with five ranibizumab injections over a period of 8 months. Peripheral venous blood samples were taken at each visit over a period of 12 months and plasma was extracted. Plasma VEGF 165 levels were determined using enzyme-linked immunosorbent assay and were assayed both pre- and post-immunodepletion to remove complexed VEGF.Results
Plasma VEGF 165 levels proved labile following intravitreal injection of ranibizumab. Levels increased by 30% above baseline following the first intravitreal ranibizumab injection, but then returned to baseline despite two subsequent injections. There was then a rebound increase of 67% in total plasma VEGF levels following a further injection, which remained above baseline for 12 weeks despite two further intravitreal ranibizumab injections. Baseline levels were re-attained 26 weeks after the final injection.Conclusions
These results suggest intravitreal ranibizumab injections can cause significant, multiphasic changes in systemic VEGF levels. This may be of particular clinical significance in children as VEGF is known to be vital in the development of major organs, in addition to its role in the maintenance of normal organ function in adults. 相似文献62.
Kathryn Fitch Thomas Weisman Tyler Engel Adam Turpcu Helen Blumen Yamina Rajput Purav Dave 《American Health & Drug Benefits》2015,8(6):300-308
Background
Diabetic retinopathy is one of the most common complications of diabetes. The screening of patients with diabetes to detect retinopathy is recommended by several professional guidelines but is an underutilized service.Objective
To analyze the relationship between the frequency of retinopathy screening and the cost of care in adult patients with diabetes.Methods
Truven Health MarketScan commercial databases (2000–2013) were used to identify the diabetic population aged 18 to 64 years for the performance of a 2001–2013 annual trend analysis of patients with type 1 and type 2 diabetes and a 10-year longitudinal analysis of patients with newly diagnosed type 2 diabetes. In the trend analysis, the prevalence of diabetes, screening rate, and allowed cost per member per month (PMPM) were calculated. In the longitudinal analysis, data from 4 index years (2001–2004) of patients newly diagnosed with type 2 diabetes were combined, and the costs were adjusted to be comparable to the 2004 index year cohort, using the annual diabetes population cost trends calculated in the trend analysis. The longitudinal population was segmented into the number of years of diabetic retinopathy screening (ie, 0, 1–4, 5–7, and 8–10), and the relationship between the years of screening and the PMPM allowed costs was analyzed. The difference in mean incremental cost between years 1 and 10 in each of the 4 cohorts was compared after adjusting for explanatory variables.Results
In the trend analysis, between 2001 and 2013, the prevalence of diabetes increased from 3.93% to 5.08%, retinal screening increased from 26.27% to 29.58%, and the average total unadjusted allowed cost of care for each patient with diabetes increased from $822 to $1395 PMPM. In the longitudinal analysis, the difference between the screening cohorts’ mean incremental cost increase was $185 between the 0- and 1–4–year cohorts (P <.003) and $202 between the 0- and 5–7–year cohorts (P <.023). The cost differences between the other cohorts, including $217 between the 0- and 8–10–year cohorts (P <.066), were not statistically significant.Conclusions
Based on our analysis, the annual retinopathy screening rate for patients with diabetes has remained low since 2001, and has been well below the guideline-recommended screening levels. For patients with type 2 diabetes, the mean increase in healthcare expenditures over a 10-year period after diagnosis is not statistically different among those with various retinopathy screening rates, although the increase in healthcare spending is lower for patients with diabetes who were not screened for retinopathy compared with patients who did get screened. 相似文献63.
Dave Singh 《British journal of clinical pharmacology》2015,79(5):695-708
Fixed dose combination (FDC) dual bronchodilators that co-administer a long acting β2-adrenoceptor agonist (LABA) and a long acting muscarinic antagonist (LAMA) are a new class of inhaled treatment for chronic obstructive pulmonary disease (COPD). This review focuses on the clinical evidence for the benefit of LABA/LAMA FDCs compared with monocomponent treatments, and also compared with active comparators that are widely used for the treatment of COPD, namely tiotropium and salmeterol-fluticasone. Novel FDC dual bronchodilators include QVA149 and umeclidinium/vilanterol (UMEC/VI). Long term clinical trials show that QVA149 and UMEC/VI are superior to monocomponent therapy in terms of trough forced expiratory volume in 1 s (FEV1), although the FEV1 improvement was limited to approximately 80–90% of the added monocomponent values. This suggests that the effect of combining a LABA and a LAMA is not fully additive. LABA/LAMA FDC were associated with the largest mean changes in symptoms and health status that were above the minimal clinically important difference, in contrast to the monocomponents. Furthermore, these LABA/LAMA FDCs demonstrated superiority over the active comparators tiotropium and salmeterol-fluticasone in terms of trough FEV1 and patient-reported outcomes. LABA/LAMA FDCs offer a simplified means of maximizing bronchodilation for COPD patients, with the improvements in lung function being mirrored by benefits in terms of symptoms and exacerbations. The use of LABA/LAMA FDCs in clinical practice is set to grow and further studies are needed to define their optimal place in treatment guidelines. 相似文献
64.
Pradyuman Dave M.D. Jose Romeu M.D. Allan Selbst M.D. 《The American journal of gastroenterology》1983,78(11):745-746
The mortality rate in spontaneous bacterial peritonitis is reportedly high. Patients rarely survive the initial infection. Most patients die either because of infection or end-stage liver disease. A patient with alcoholic cirrhosis and portal hypertension with five distinct episodes of spontaneous bacterial peritonitis over a 2 1/2-year period is described. 相似文献
65.
Reproductive Hormones and Longitudinal Change in Bone Mineral Density and Incident Fracture Risk in Older Men: The Concord Health and Aging in Men Project 下载免费PDF全文
Benjumin Hsu Robert G Cumming Markus J Seibel Vasi Naganathan Fiona M Blyth Kerrin Bleicher Aneesh Dave David G Le Couteur Louise M Waite David J Handelsman 《Journal of bone and mineral research》2015,30(9):1701-1708
The objectives of this study were to examine relationships between baseline levels of reproductive hormones in older men and (1) change in bone mineral density (BMD) over 5 years and (2) incident fractures over an average of 6 years' follow‐up. A total of 1705 men aged 70 years and older from the Concord Health and Ageing in Men Project (CHAMP) study were assessed at baseline (2005–2007), 2 years follow‐up (2007–2009), and 5 years follow‐up (2010–2013). At baseline, testosterone (T), dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) were measured by liquid chromatography–tandem mass spectrometry (LC‐MS/MS), and sex hormone–binding globulin (SHBG), luteinizing hormone (LH), and follicle‐stimulating hormone (FSH) by immunoassay. Hip BMD was measured by dual X‐ray absorptiometry (DXA) at all three time‐points. Fracture data were collected at 4‐monthly phone calls and verified radiographically. Statistical modeling was by general estimating equations and Cox model regression. Univariate analyses revealed inverse associations for serum SHBG, FSH, and LH and positive association for E1 but not DHT or E2 with BMD loss at the hip across the three time points. Serum levels of SHBG (β = –0.071), FSH (β = –0.085), LH (β = –0.070), and E1 (β = 0.107) remained significantly associated with BMD loss in multivariate‐adjusted models; however, we were unable to identify any thresholds for accelerated BMD loss according to reproductive steroids. Incident fractures (all, n = 171; hip, n = 44; and nonvertebral, n = 139) were all significantly associated with serum SHBG, FSH, and LH levels in univariate models but none remained significantly associated in multivariate‐adjusted model. Serum T, DHT, E2, and E1 levels were not associated with incident fractures in univariate or multivariate‐adjusted analyses. In older men, lower serum SHBG, FSH, and LH and higher E1 levels protected against loss of BMD without increasing fracture rate. This means these reproductive variables may be considered as novel biomarkers of bone health during male aging. © 2015 American Society for Bone and Mineral Research. 相似文献
66.
Previously reported cases of botulism in infants have been diagnosed as infant botulism; that is, botulism caused by intestinal colonization by Clostridium botulinum with intraluminal production and absorption of toxin. Foodborne botulism is caused by ingestion of preformed toxin. We describe an unusual case of foodborne botulism in a 6-month-old infant caused by the ingestion of improperly prepared home-canned baby food. This represents the youngest age of onset for foodborne botulism in the United States of which we are aware and illustrates the need to rule out foodborne botulism, which represents a public health emergency, regardless of the patient's age. The diagnosis could have been readily missed or delayed in this case because the weakness was rapidly progressive rather than insidious, as is typical of infant botulism. 相似文献
67.
68.
Saeed Ahmed Maria H Kim Amanda C Dave Rachael Sabelli Kondwani Kanjelo Geoffrey A Preidis Thomas P Giordano Elizabeth Chiao Mina Hosseinipour Peter N Kazembe Frank Chimbwandira Elaine J Abrams 《Journal of the International AIDS Society》2015,18(1)
Background
Early identification and entry into care is critical to reducing morbidity and mortality in children with HIV. The objective of this report is to describe the impact of the Tingathe programme, which utilizes community health workers (CHWs) to improve identification and enrolment into care of HIV-exposed and -infected infants and children.Methods
Three programme phases are described. During the first phase, Mentorship Only (MO) (March 2007–February 2008) on-site clinical mentorship on paediatric HIV care was provided. In the second phase, Tingathe-Basic (March 2008–February 2009), CHWs provided HIV testing and counselling to improve case finding of HIV-exposed and -infected children. In the final phase, Tingathe-PMTCT (prevention of mother-to-child transmission) (March 2009–February 2011), CHWs were also assigned to HIV-positive pregnant women to improve mother-infant retention in care. We reviewed routinely collected programme data from HIV testing registers, patient mastercards and clinic attendance registers from March 2005 to March 2011.Results
During MO, 42 children (38 HIV-infected and 4 HIV-exposed) were active in care. During Tingathe-Basic, 238 HIV-infected children (HIC) were newly enrolled, a six-fold increase in rate of enrolment from 3.2 to 19.8 per month. The number of HIV-exposed infants (HEI) increased from 4 to 118. During Tingathe-PMTCT, 526 HIC were newly enrolled over 24 months, at a rate of 21.9 patients per month. There was also a seven-fold increase in the average number of exposed infants enrolled per month (9.5–70 patients per month), resulting in 1667 enrolled with a younger median age at enrolment (5.2 vs. 2.5 months; p<0.001).During the Tingathe-Basic and Tingathe-PMTCT periods, CHWs conducted 44,388 rapid HIV tests, 7658 (17.3%) in children aged 18 months to 15 years; 351 (4.6%) tested HIV-positive. Over this time, 1781 HEI were enrolled, with 102 (5.7%) found HIV-infected by positive PCR. Additional HIC entered care through various mechanisms (including positive linkage by CHWs and transfer-ins) such that by February 2011, a total of 866 HIC were receiving care, a 23-fold increase from 2008.Conclusions
A multipronged approach utilizing CHWs to conduct HIV testing, link HIC into care and provide support to PMTCT mothers can dramatically improve the identification and enrolment into care of HIV-exposed and -infected children. 相似文献69.
Ashish Correa Achint Patel Kinsuk Chauhan Harshil Shah Aparna Saha Mihir Dave Priti Poojary Abhishek Mishra Narender Annapureddy Shaman Dalal Ioannis Konstantinidis Renu Nimma Shiv Kumar Agarwal Lili Chan Girish Nadkarni Sean Pinney 《Journal of cardiac failure》2018,24(7):442-450