全文获取类型
收费全文 | 1517篇 |
免费 | 123篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 40篇 |
妇产科学 | 96篇 |
基础医学 | 245篇 |
口腔科学 | 125篇 |
临床医学 | 135篇 |
内科学 | 249篇 |
皮肤病学 | 48篇 |
神经病学 | 160篇 |
特种医学 | 30篇 |
外科学 | 125篇 |
综合类 | 4篇 |
预防医学 | 154篇 |
眼科学 | 13篇 |
药学 | 70篇 |
肿瘤学 | 126篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 13篇 |
2021年 | 16篇 |
2020年 | 21篇 |
2019年 | 25篇 |
2018年 | 41篇 |
2017年 | 30篇 |
2016年 | 37篇 |
2015年 | 39篇 |
2014年 | 43篇 |
2013年 | 54篇 |
2012年 | 112篇 |
2011年 | 105篇 |
2010年 | 56篇 |
2009年 | 50篇 |
2008年 | 105篇 |
2007年 | 95篇 |
2006年 | 90篇 |
2005年 | 87篇 |
2004年 | 85篇 |
2003年 | 78篇 |
2002年 | 63篇 |
2001年 | 36篇 |
2000年 | 37篇 |
1999年 | 19篇 |
1998年 | 9篇 |
1997年 | 11篇 |
1996年 | 12篇 |
1995年 | 8篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 40篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 20篇 |
1988年 | 15篇 |
1987年 | 15篇 |
1986年 | 18篇 |
1985年 | 17篇 |
1984年 | 19篇 |
1983年 | 8篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 10篇 |
1979年 | 16篇 |
1978年 | 7篇 |
1977年 | 3篇 |
排序方式: 共有1646条查询结果,搜索用时 15 毫秒
41.
F Chang S Syrj?nen Q Shen L Wang D Wang K Syrj?nen 《Scandinavian journal of gastroenterology》1992,27(7):553-563
A series of 71 surgically resected esophageal squamous cell carcinomas, including 51 cases of formalin-fixed samples and 20 cases of fresh biopsy specimens derived from the high-incidence area of esophageal cancer in China, were systematically analyzed for the presence of human papillomavirus (HPV) infections by light microscopy, electron microscopy (TEM), in situ DNA hybridization, Southern blot hybridization, and polymerase chain reaction (PCR) techniques. On light microscopy, HPV-suggestive lesions were found in a total of 49.0% (25 of 51) of the specimens, including the flat type (22 of 51) and, less frequently, an inverted one (2 of 51). Of the 51 formalin-fixed, paraffin-embedded specimens, 43.1% (22 of 51) contained HPV DNA sequences by in situ hybridization. Of the positive cases, HPV 6 was present in three (5.9%), HPV 11 in three (5.9%), HPV 16 in eight (15.7%), HPV 18 in six (11.8%), double infections with HPV 11/18 in one (2.0%), and HPV 16/18 in one. In most cases the HPV-positive signals were localized in the hyperplastic and/or dysplastic epithelium adjacent to invasive carcinomas. In two specimens, however, HPV DNA sequences were found in the frankly invasive lesions, one being HPV 6 and the other HPV 18. On TEM, HPV-like particles located in the nuclei of koilocytotic cells were demonstrated in two of the five specimens previously shown to be HPV-positive by in situ hybridization. By means of the PCR technique, all specimens positive for HPV by in situ hybridization also contained amplified HPV sequences. Moreover, three additional samples negative by in situ hybridization were found to contain HPV 11 DNA sequences. Of the 20 DNA samples extracted from the fresh carcinoma samples (containing some surrounding tissues as well) 9 were shown to contain HPV DNA sequences by Southern blot hybridization under low-stringency conditions. Of these, eight samples remained positive when hybridized with the probe cocktail of HPV 11, 16, 18, and 30 DNA under high-stringency conditions. HPV DNA sequences in these carcinoma specimens appeared to be present mainly in an integrated form. The present results confirm the HPV involvement in esophageal squamous cell lesions and suggest that HPV infection might be an important etiologic factor in the pathogenesis of esophageal cancer, most probably acting synergistically with other carcinogenic factors. 相似文献
42.
Tanner LM Näntö-Salonen K Rashed MS Kotilainen S Aalto M Venetoklis J Niinikoski H Huoponen K Simell O 《Metabolism: clinical and experimental》2008,57(4):549-554
The aim of the study was to investigate the prevalence and mechanisms of development of carnitine deficiency in patients with lysinuric protein intolerance (LPI). In our cohort of 37 Finnish patients with LPI, 8 (8-52 years of age) have been diagnosed with hypocarnitinemia. Their free and total serum carnitine levels, acyl carnitine profiles, renal function, diet, and medication were compared with the data from 8 age- and sex-matched patients with LPI not treated with carnitine supplementation. In patients with LPI, hypocarnitinemia was strongly associated with female sex, renal insufficiency, and the use of ammonia-scavenging drugs. Of the 8 hypocarnitinemic patients, 3 complained of muscle weakness, and their symptoms disappeared during carnitine supplementation. Oral lysine supplementation did not correct hypocarnitinemia in our patients. The patients with LPI are at considerable risk for carnitine deficiency. Supplementation of hypocarnitinemic LPI patients with oral L-carnitine improved serum total carnitine values, but the ratio of free and total carnitine remained subnormal in all supplemented patients except one. Furthermore, decreased ratio of free and total serum carnitine was common even in LPI patients with normal total serum carnitine concentration. 相似文献
43.
Emma Aarnio Risto Huupponen Katri Hmeen‐Anttila Merja Merikoski Jaana Puhakka Maarit J. Korhonen 《Basic & clinical pharmacology & toxicology》2019,124(4):416-422
Direct oral anticoagulants provide an alternative to vitamin K antagonists for the anticoagulation therapy in atrial fibrillation (AF). The availability of several treatment options with different attributes makes shared decision‐making appropriate for the choice of anticoagulation therapy. The aim of this study was to understand how physicians choose an oral anticoagulant (OAC) for patients with AF and how physicians view patients’ participation in this decision. Semi‐structured interviews with 17 Finnish physicians (eight general practitioners and nine specialists) working in the public sector were conducted. An interview guide on experience, prescribing and opinions about oral anticoagulants was developed based on previous literature. The data were thematically analysed using deductive and inductive approaches. Based on the interviews, patient's opinion was the most influential factor in decision‐making when there were no clinical factors limiting the choice between OACs. Of patient's preferences, the most important was the attitude towards co‐payments of OACs. Patients’ opinions on monitoring of treatment, dosing and antidote availability were also mentioned by the interviewees. The choice of an OAC in AF was patient‐centred as all interviewees expressed that patient's opinion affects the choice. 相似文献
44.
45.
46.
Avoranta ST Korkeila EA Syrjänen KJ Pyrhönen SO Sundström JT 《World journal of gastroenterology : WJG》2012,18(33):4549-4556
AIM: To investigate the prognostic value of CD44 variant 6 (CD44v6), a membranous adhesion molecule, in rectal cancer.METHODS: Altogether, 210 rectal cancer samples from 214 patients treated with short-course radiotherapy (RT, n = 90), long-course (chemo) RT (n = 53) or surgery alone (n = 71) were studied with immunohistochemistry for CD44v6. The extent and intensity of membranous and cytoplasmic CD44v6 staining, and the intratumoral membranous staining pattern, were analyzed.RESULTS: Membranous CD44v6 expression was seen in 84% and cytoplasmic expression in 81% of the cases. In 59% of the tumors with membranous CD44v6 expression, the staining pattern in the invasive front was determined as “front-positive” and in 41% as “front-negative”. The latter pattern was associated with narrower circumferential margin (P = 0.01), infiltrative growth pattern (P < 0.001), and shorter disease-free survival in univariate survival analysis (P = 0.022) when compared to the “front-positive” tumors.CONCLUSION: The lack of membranous CD44v6 in the rectal cancer invasive front could be used as a method to identify patients at increased risk for recurrent disease. 相似文献
47.
48.
Anneli Eerola Eero Jokinen Talvikki Boldt Ilkka P. Mattila Jaana I. Pihkala 《Scandinavian cardiovascular journal : SCJ》2013,47(6):370-377
Objectives. To evaluate cardiac size and function in patients with coarctation of the aorta (CoA) before and after treatment. Design. Ventricular size and function were examined by 2- and 3-dimensional echocardiography, and concentrations of natriuretic peptides measured in 15 paediatric patients before repair, and one, 6, and 12 months thereafter. Controls comprised 15 children. Results. Before repair, mitral inflow velocities and left ventricular (LV) size and wall thickness were higher in patients. Thicknesses of interventricular septum and LV posterior wall decreased after repair but increased to initial level one year thereafter. The LV end-diastolic diameter remained larger than in controls despite successful repair. The size of right ventricle increased and levels of natriuretic peptides decreased during follow-up. Levels of natriuretic peptides correlated with the smallest diameter of CoA segment and diastolic indices of LV function. Conclusion. LV hypertrophy persists and LV size remains larger than in controls after successful repair even in normotensive patients with normal growth of CoA segment. This may be due to remodelling of ventricles and the aorta caused by CoA. 相似文献
49.
50.
Dimitra Zannidi Kalliopi Karatzi Eva Karaglani Stavros Liatis Greet Cardon Violeta Iotova Kaloyan Tsochev Nevyana Chakarova Luis A. Moreno Paloma Flores-Barrantes Sándorné Radó Imre Rurik Jaana Lindström Konstantinos Makrilakis Yannis Manios the FeelDiabetes Study Group 《Journal of human nutrition and dietetics》2023,36(1):62-74