全文获取类型
收费全文 | 455篇 |
免费 | 28篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 7篇 |
妇产科学 | 7篇 |
基础医学 | 40篇 |
口腔科学 | 27篇 |
临床医学 | 46篇 |
内科学 | 147篇 |
皮肤病学 | 4篇 |
神经病学 | 32篇 |
特种医学 | 1篇 |
外科学 | 43篇 |
预防医学 | 35篇 |
眼科学 | 17篇 |
药学 | 39篇 |
中国医学 | 5篇 |
肿瘤学 | 19篇 |
出版年
2023年 | 8篇 |
2022年 | 9篇 |
2021年 | 26篇 |
2020年 | 19篇 |
2019年 | 20篇 |
2018年 | 21篇 |
2017年 | 18篇 |
2016年 | 12篇 |
2015年 | 18篇 |
2014年 | 19篇 |
2013年 | 24篇 |
2012年 | 36篇 |
2011年 | 39篇 |
2010年 | 13篇 |
2009年 | 16篇 |
2008年 | 28篇 |
2007年 | 22篇 |
2006年 | 27篇 |
2005年 | 16篇 |
2004年 | 24篇 |
2003年 | 14篇 |
2002年 | 23篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有486条查询结果,搜索用时 0 毫秒
81.
Raimundo Barbosa‐Barros MD Andrés R. Pérez‐Riera MD PhD Kimmo Koivula MD Jairo de Carvalho Santos MD Luiz C. de Abreu PhD Kjell Nikus MD 《Annals of noninvasive electrocardiology》2018,23(5)
Aortitis is one of many possible manifestations of tertiary syphilis. Aortic disease is the most common of all cardiovascular syphilitic lesions. Aortic diseases caused by tertiary syphilis include aortitis, aortic root dilation, aneurysm formation, aortic regurgitation and coronary ostial stenosis. A less common manifestation of syphilitic aortitis is coronary artery ostial narrowing related to aortic wall thickening. We report a case of a 40‐year‐old male patient admitted with a clinical picture of acute coronary syndrome (unstable angina). He had no risk factors for coronary artery disease. The physical examination revealed nothing remarkable. The admission electrocardiogram (ECG) showed ST segment depression in the anterolateral and inferior leads (Figure 1). The coronary angiogram showed critical ostial stenosis of the right (RCA) and left main coronary artery (Figure 2a, b). Cardiac‐computed tomography showed aortic wall thickening with involvement of bilateral coronary ostia (Figure 2b, c). The patient was referred for coronary bypass surgery after treatment with two doses of penicillin G. The laboratory test was strongly positive for syphilitic infection. Postoperative treatment with benzathine penicillin, in doses recommended for tertiary syphilis, was implemented. 相似文献
82.
Redondo Beatriz Vera Jesús Molina Rubén García José Antonio Ouadi Miriam Muñoz-Hoyos Antonio Jiménez Raimundo 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2018,256(5):1023-1030
Graefe's Archive for Clinical and Experimental Ophthalmology - Attention-deficit/hyperactivity disorder (ADHD) is one of the most common paediatric neurobehavioural disorders causing multiple... 相似文献
83.
Torres MC das Chagas L Pinto F Braz-Filho R Silveira ER Pessoa OD Jorge RJ Ximenes RM Monteiro HS Monteiro Evangelista JS Diz-Filho EB Toyama MH 《Journal of natural products》2011,74(10):2168-2173
Three new solanidane alkaloids bearing a 22,23-epoxy ring (1-3) and four known compounds were isolated from leaves of Solanum campaniforme. The structures were determined using spectroscopic techniques, including 1D and 2D NMR, and HRESIMS experiments. The antiophidic activity of the alkaloids was tested against Bothrops pauloensis venom. Compounds 1-3 completely inhibited myotoxicity without inhibiting phospholipase A2 activity of the venom, while hemorrhage and skin necrosis were significantly reduced in the presence of alkaloids 1 and 2. 相似文献
84.
Francisco Y. B. Macedo Lívia T. C. Mourão Raimundo C. Palheta Jr. Davi M. Jucá Roberto C. P. Lima Jr. José de Sá C. Neto Pedro J. C. Magalhães Armênio A. Santos Marcellus H. L. P. Souza Gerly A. C. Brito Ronaldo A. Ribeiro 《Cancer chemotherapy and pharmacology》2011,67(4):935-943
Purpose
Ifosfamide (IFS) is often involved in the occurrence of hemorrhagic cystitis due to direct contact of its metabolite acrolein with uroepithelium. It has been shown that COX-2 is involved in this pathogenesis. Thus, we aimed to study the functional changes on the urinary bladder in the putative modifications induced by IFS, as well as the COX-2 role in this process.Materials and methods
IFS-treated rats were evaluated by cystometrography in absence or presence of COX inhibitors indomethacin or etoricoxib or in the presence of mesna. Experiments with isolated strips of urinary bladder obtained from animals with IFS-induced cystitis, either treated or not treated with COX inhibitors or mesna, were performed. Histological analyses, immunohistochemistry for COX-2, and measurement of plasma PGE2 were also performed.Results
IFS treatment caused severe inflammation of the bladder tissue. Cystometrography recordings of IFS-treated rats revealed bladder with increased micturition frequency and enhanced filling intravesical pressure. Contractility of the isolated smooth muscle from the rat’s bladder with IFS-induced cystitis showed decreased force development in response to KCl and CCh. Almost all effects induced by IFS were ameliorated by the use of COX inhibitors or mesna. Enzyme expression in the urinary bladder tissue was positive, and plasma concentration of PGE2 was increased in IFS-treated animals and decreased significantly in etoricoxib-treated animals.Conclusions
IFS causes important changes in the micturition physiology in rats, and the inhibition of the isoenzyme COX-2 could be an important event that could prevent the detrimental effects elicited by IFS-induced hemorrhagic cystitis. 相似文献85.
Morande PE Zanetti SR Borge M Nannini P Jancic C Bezares RF Bitsmans A González M Rodríguez AL Galmarini CM Gamberale R Giordano M 《Investigational new drugs》2012,30(5):1830-1840
Aplidin is a novel cyclic depsipeptide, currently in Phase II/III clinical trials for solid and hematologic malignancies. The aim of this study was to evaluate the effect of Aplidin in chronic lymphocytic leukemia (CLL), the most common leukemia in the adult. Although there have been considerable advances in the treatment of CLL over the last decade, drug resistance and immunosuppression limit the use of current therapy and warrant the development of novel agents. Here we report that Aplidin induced a dose- and time-dependent cytotoxicity on peripheral blood mononuclear cells (PBMC) from CLL patients. Interestingly, Aplidin effect was markedly higher on monocytes compared to T lymphocytes, NK cells or the malignant B-cell clone. Hence, we next evaluated Aplidin activity on nurse-like cells (NLC) which represent a cell subset differentiated from monocytes that favors leukemic cell progression through pro-survival signals. NLC were highly sensitive to Aplidin and, more importantly, their death indirectly decreased neoplasic clone viability. The mechanisms of Aplidin-induced cell death in monocytic cells involved activation of caspase-3 and subsequent PARP fragmentation, indicative of death via apoptosis. Aplidin also showed synergistic activity when combined with fludarabine or cyclophosphamide. Taken together, our results show that Aplidin affects the viability of leukemic cells in two different ways: inducing a direct effect on the malignant B-CLL clone; and indirectly, by modifying the microenvironment that allows tumor growth. 相似文献
86.
87.
88.
Moreira ED de Oliveira BG Neves RC Costa S Karic G Filho JO 《Journal of pediatric and adolescent gynecology》2006,19(2):81-87
STUDY OBJECTIVE: To assess knowledge and attitudes of young uninsured women toward human papillomavirus (HPV) vaccination and clinical trials. DESIGN: Cross-sectional study. SETTING: Clinic-based sample in Brazil. PARTICIPANTS: A consecutive sample of 204 women aged 16 to 23 years, attending a public outpatient gynecological clinic. INTERVENTIONS: A questionnaire administered by in-person interview. MAIN OUTCOME MEASURES: Data on knowledge and attitudes towards HPV vaccination. RESULTS: Overall, 72% of the respondents would enroll in a HPV vaccine trial, despite the fact that 69% of women were ignorant of what HPV may cause, and only 10% acknowledged that HPV might lead to cervical cancer. The need of a placebo arm (31%) and three vaccinations injections (26%) were the trial design characteristics most cited for deterring participation. Factors promoting participation were "careful/detailed consultations by the same physician" (92%), "access to more information on women's health" (84%), and "office visits on time" (79%); whereas "clinic too far from home" (36%), "fear of adverse events" (29%), and "gynecologic examination discomfort" (25%) were the most commonly reported reasons for not enrolling in a trial. Being sexually active, more than three lifetime sexual partners and perception of high risk for cervical cancer were predictors of participation in a HPV vaccine trial. CONCLUSIONS: Knowledge of HPV infection and cervical cancer is low in this urban, young population. Thus, when planning HPV vaccine trials, it is important to consider implementing educational programs to provide knowledge of the benefits of a preventive vaccine and information on the etiology of and risk factors for cervical cancer. 相似文献
89.
Land use effects in groundwater composition of an alluvial aquifer (Trussu River, Brazil) by multivariate techniques 总被引:4,自引:0,他引:4
de Andrade EM Palácio HA Souza IH de Oliveira Leão RA Guerreiro MJ 《Environmental research》2008,106(2):170-177
Multivariate statistical techniques, cluster analysis (CA) and factor analysis/principal component analysis (FA/PCA), were applied to analyze the similarities or dissimilarities among the sampling sites to identify spatial and temporal variations in water quality and sources of contamination (natural and anthropogenic). The aquifer under study is supplied by the Trussu River, which has a general direction from west to east, within Iguatu County, Ceará, Brazil. Groundwater samples were collected in four shallow wells, located at the Trussu River alluvial, from October 2002 to February 2004. The samples were analyzed for 13 parameters: pH, electrical conductivity (EC), Na, Ca, Mg, K, Cl, HCO(3), PO(4), NH(4)-N, NO(3)-N, SO(4), and sodium adsorption ratio (SAR). Two zones were very well differentiated based on cluster analysis results, and implied a relation to geographic position and time variation. One zone called UL-upland region-corresponds to upland of studied area, used mainly for irrigation and livestock activities. The other zone called DL-downland region-corresponds to the region downstream and is occupied by human settlements. These results may be used to reduce the number of samples analyzed both in space and time, without too much loss of information. Three major independent factors that define water quality in the UL region and four in DL region were identified in the PCA. At both regions, rotated component (RC) loadings identified that the variables responsible for water quality composition are mainly related to soluble salts variables (natural process) and nutrients (high loads of NO(3)-N, NH(4)-N), expressing anthropogenic activities. RC also revealed that hydrochemical processes were the major factors responsible for water quality. 相似文献
90.