全文获取类型
收费全文 | 2540篇 |
免费 | 140篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 58篇 |
妇产科学 | 39篇 |
基础医学 | 268篇 |
口腔科学 | 31篇 |
临床医学 | 171篇 |
内科学 | 758篇 |
皮肤病学 | 80篇 |
神经病学 | 148篇 |
特种医学 | 53篇 |
外科学 | 408篇 |
综合类 | 40篇 |
一般理论 | 2篇 |
预防医学 | 115篇 |
眼科学 | 75篇 |
药学 | 172篇 |
中国医学 | 5篇 |
肿瘤学 | 259篇 |
出版年
2023年 | 23篇 |
2022年 | 42篇 |
2021年 | 94篇 |
2020年 | 55篇 |
2019年 | 81篇 |
2018年 | 58篇 |
2017年 | 57篇 |
2016年 | 64篇 |
2015年 | 71篇 |
2014年 | 124篇 |
2013年 | 167篇 |
2012年 | 242篇 |
2011年 | 257篇 |
2010年 | 120篇 |
2009年 | 112篇 |
2008年 | 183篇 |
2007年 | 136篇 |
2006年 | 182篇 |
2005年 | 131篇 |
2004年 | 106篇 |
2003年 | 86篇 |
2002年 | 69篇 |
2001年 | 30篇 |
2000年 | 15篇 |
1999年 | 15篇 |
1998年 | 12篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 7篇 |
1991年 | 11篇 |
1990年 | 10篇 |
1989年 | 8篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1982年 | 3篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1969年 | 2篇 |
1964年 | 2篇 |
1933年 | 3篇 |
1930年 | 4篇 |
1929年 | 6篇 |
排序方式: 共有2693条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
Efficacy of the Za self-expandable metal stent for palliation of malignant biliary obstruction 总被引:3,自引:0,他引:3
Varadarajulu S Tutuian R Gostout C Kozarek R Wilcox CM Cotton PB 《Journal of clinical gastroenterology》2004,38(1):77-80
BACKGROUND: The efficacy and safety of the uncoated self-expandable Za metal stent for palliation of malignant distal biliary obstruction was prospectively analyzed. METHODS: Twenty-one patients with unresectable malignant tumors involving mid to distal common bile duct who presented with obstructive jaundice underwent endoscopic implantation of an uncoated self-expandable metal stent. Technical success with stent placement, adverse events, patient survival, duration of stent patency, and device performance were analyzed. RESULTS: Endoscopic biliary stenting was successful in all patients. No adverse events were encountered. The mean follow-up period of the 21 patients was 128 days (range, 3-263): 14 died of progressive disease at mean of 81 days (range, 3-210), 3 remain alive (at days 239, 250, and 263), and 4 were lost to follow-up (at days 90, 91, 92, and 116). The mean duration of stent patency was 249 days. Tumor ingrowth was observed in one patient (5%). Minor technical problems were encountered in 3 patients: 1 proximal deployment, 1 distal deployment, and difficulty associated with the delivery system in 1. CONCLUSIONS: The Za-metal stent provided effective palliation for patients with inoperable malignant biliary tumors. Although minor technical problems were encountered with stent deployment, the overall stent patency, efficacy, and safety profile appear satisfactory. 相似文献
25.
26.
Pulmonary Langerhans cell histiocytosis: emerging concepts in pathobiology,radiology, and clinical evolution of disease 总被引:3,自引:0,他引:3
Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon disorder of adult smokers associated with a significant morbidity. Arising from the aberrant accumulation of Langerhans and other immune cells, PLCH tends to cause a relatively isolated pulmonary involvement as compared to other forms of Langerhans cell (LC) and histiocytic disorders. Increased knowledge of cytokine triggers, dendritic cell trafficking, and clonality of LC populations in PLCH have resulted in an improved understanding of the pathobiology of PLCH. High-resolution CT (HRCT) of the chest has led to better appreciation of nodular and cystic radiographic abnormalities characteristic of the disease. Correlation of HRCT abnormalities with lung pathologic changes has led to an improved comprehension of clinical evolution of PLCH. Current clinical predictors for PLCH outcomes remain poor, although long-term follow-up and radiologic monitoring may help to define disease progression. This review discusses advances in PLCH emphasizing the etiopathologic bases of the disease and currently available radiologic modalities for monitoring disease progression. 相似文献
27.
Monroe J King Samuel C Bukantz Sharon Phillips Shyam S Mohapatra Tomas Tamulis Richard F Lockey 《Allergy and asthma proceedings》2004,25(5):321-325
Serum IgE (total and five specific) and eosinophil cationic protein (ECP) levels were compared in elderly physician-diagnosed patients with asthma with non-asthmatic controls matched by age and gender to ascertain whether elevated levels are indicators of asthma in the elderly. All subjects and controls were non-smokers. The subjects were participants in the Florida Geriatric Research Program (FGRP), a longitudinal aging study that tracks the health status of people 65 years and older. Frozen sera from 33 randomly selected asthmatic patients and 21 controls, none of whom had any other chronic respiratory disease, such as chronic obstructive pulmonary disease (COPD), all between the ages of 65 and 90, were assessed for total IgE; five specific IgE concentrations (for cat, ragweed, German cockroach, Dermatophagoides pteronyssinus (Dp) and live oak); and ECP levels using the Pharmacia Unicap System. The odds of an elderly asthmatic patient having a total IgE of > 100 KU/L were higher than that for a non-asthmatic patient (odds ratio (OR) = 13.0; Mantel-Haenszel (MH) p = 0.005). The odds of elderly asthmatic patients having at least one positive serum specific IgE compared to elderly age-matched non-asthmatic patients were higher (OR = 21.2; MH p = 0.001). Among the five specific IgE concentrations, only IgE for Dp was higher in asthmatic than in non-asthmatic patients (OR = 13.00; MH p = 0.005). The ECP level was not significantly different between elderly asthmatic and non-asthmatic patients (asthmatic mean = 20.7 microg/L, SE = 0.48; control mean = 19.5 microg/L. SE = 0.76) (mean for younger adults 4.4 microg/L, Pharmacia Diagnostics). The serum of elderly asthmatic patients is more likely to have elevated total IgE and a positive specific IgE to Dp. ECP is elevated in elderly subjects but is not an indicator of asthma. 相似文献
28.
Bommena Hanumantha Rao Inti Venkata Subramanyeswara Rao Vysyaraju Ravi Kanth Korrapati Venkata Vara Prasada Rao K. Balamurali Krishna Bethanabatla Syama Sundar 《Scientia pharmaceutica》2015,83(3):465-478
Drug product purity and potency are of most significance in the regulatory market as we notice many recalled batches worldwide, particularly in the US and Japan. Olmesartan Medoxomil is an anti-hypertensive drug. The present invention relates to a process for the preparation of Olmesartan Medoxomil with 99.9% purity in an overall 62% yield. The synthesis includes three isolations and one purification with easy plant operations. This process describes the formation and control of each individual impurity in all stages. This process for Olmesartan Medoxomil and its intermediates is competent for industrial production in very short reaction time intervals with an appreciable yield and high purity. 相似文献
29.
Visceral leishmaniasis: current status of control,diagnosis, and treatment,and a proposed research and development agenda 总被引:13,自引:0,他引:13
Guerin PJ Olliaro P Sundar S Boelaert M Croft SL Desjeux P Wasunna MK Bryceson AD 《The Lancet infectious diseases》2002,2(8):494-501
Visceral leishmaniasis is common in less developed countries, with an estimated 500000 new cases each year. Because of the diversity of epidemiological situations, no single diagnosis, treatment, or control will be suitable for all. Control measures through case finding, treatment, and vector control are seldom used, even where they could be useful. There is a place for a vaccine, and new imaginative approaches are needed. HIV co-infection is changing the epidemiology and presents problems for diagnosis and case management. Field diagnosis is difficult; simpler, less invasive tests are needed. Current treatments require long courses and parenteral administration, and most are expensive. Resistance is making the mainstay of treatment, agents based on pentavalent antimony, useless in northeastern India, where disease incidence is highest. Second-line drugs (pentamidine and amphotericin B) are limited by toxicity and availability, and newer formulations of amphotericin B are not affordable. The first effective oral drug, miltefosine, has been licensed in India, but the development of other drugs in clinical phases (paromomycin and sitamaquine) is slow. No novel compound is in the pipeline. Drug combinations must be developed to prevent drug resistance. Despite these urgent needs, research and development has been neglected, because a disease that mainly affects the poor ranks as a low priority in the private sector, and the public sector currently struggles to undertake the development of drugs and diagnostics in the absence of adequate funds and infrastructure. This article reviews the current situation and perspectives for diagnosis, treatment, and control of visceral leishmaniasis, and lists some priorities for research and development. 相似文献
30.