全文获取类型
收费全文 | 4361篇 |
免费 | 263篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 51篇 |
妇产科学 | 73篇 |
基础医学 | 550篇 |
口腔科学 | 335篇 |
临床医学 | 370篇 |
内科学 | 1113篇 |
皮肤病学 | 94篇 |
神经病学 | 263篇 |
特种医学 | 213篇 |
外科学 | 697篇 |
综合类 | 26篇 |
预防医学 | 297篇 |
眼科学 | 19篇 |
药学 | 198篇 |
中国医学 | 14篇 |
肿瘤学 | 306篇 |
出版年
2023年 | 35篇 |
2022年 | 59篇 |
2021年 | 137篇 |
2020年 | 95篇 |
2019年 | 109篇 |
2018年 | 143篇 |
2017年 | 104篇 |
2016年 | 110篇 |
2015年 | 143篇 |
2014年 | 171篇 |
2013年 | 216篇 |
2012年 | 338篇 |
2011年 | 294篇 |
2010年 | 194篇 |
2009年 | 200篇 |
2008年 | 287篇 |
2007年 | 246篇 |
2006年 | 241篇 |
2005年 | 255篇 |
2004年 | 249篇 |
2003年 | 212篇 |
2002年 | 196篇 |
2001年 | 64篇 |
2000年 | 58篇 |
1999年 | 52篇 |
1998年 | 35篇 |
1997年 | 25篇 |
1996年 | 18篇 |
1995年 | 17篇 |
1994年 | 13篇 |
1993年 | 11篇 |
1992年 | 30篇 |
1991年 | 38篇 |
1990年 | 26篇 |
1989年 | 30篇 |
1988年 | 22篇 |
1987年 | 18篇 |
1986年 | 21篇 |
1985年 | 13篇 |
1984年 | 14篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1980年 | 15篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1971年 | 6篇 |
1969年 | 4篇 |
1968年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有4643条查询结果,搜索用时 15 毫秒
121.
Manuel R Cervetti Mariano Camporrotondo Paz Ricapito Juan C Espinoza Fernando Piccinini Mariano Vrancic Daniel Navia 《Journal of cardiac surgery》2019,34(4):214-215
A 67‐year‐old man presented with chest pain. Clinical examination revealed hypertension (160/90 mm Hg). Electrocardiogram indicated no acute coronary syndrome and cardiac enzymes were normal. Catheterization was performed owing to the patient’s continuing chest pain and ascending aortogram revealed irregular aortic wall. A computed tomography image showed the shape of penetrating ulcer. The patient was taken to the operating room and intraoperative examination confirmed the diagnosis of penetrating atherosclerotic ulcer (PAU). Coronary artery bypass graft and bovine pericardial patch repair of PAU was performed. A bovine pericardial patch was done as aortic root was heavily calcified and was easy to handle and more hemostatic. 相似文献
122.
Core-Shell Arginine-Containing Chitosan Microparticles for Enhanced Transcorneal Permeation of Drugs
Nicolò Mauro Giulia Di Prima Paola Varvarà Mariano Licciardi Gennara Cavallaro Gaetano Giammona 《Journal of pharmaceutical sciences》2019,108(2):960-969
Chitosan oligosaccharide (C) was functionalized with l-arginine (A) and short hydrocarbon chains (C8) to design an amphiphilic copolymer, henceforth CAC8, leading to microparticles (MPs) consisting of an arginine-decorated hydrophilic shell and inner hydrophobic domains allowing the encapsulation of high amount hydrophobic drugs such as sorafenib tosylate (>10% w/w). l-arginine side chains were selected in order to impart the final MPs enhanced transcorneal penetration properties, thus overcoming the typical biological barriers which hamper the absorption of drugs upon topical ocular administration. The mucoadhesive properties and drug release profile of the CAC8 MPs (CAC8-MPs) were studied, showing that CAC8-MPs can strongly interact with mucin, and thus gradually release their payload in situ to potentially improve the bioavailability of the drug after topical administration. In vitro transcorneal studies also showed that CAC8-MPs are endowed with effective permeation enhancer ability combined with negligible toxicity. 相似文献
123.
Clinical validation of the nursing diagnosis of ineffective protection in haemodialysis patients 下载免费PDF全文
Jéssica Dantas de Sá Tinôco RN MsN Maria das Graças Mariano Nunes de Paiva RN MsN Kadyjina Daiane Batista Lucio RN Maria Isabel da Conceição Dias Fernandes RN MsN Marcos Venicios de Oliveira Lopes RN MsN PhD Ana Luisa Brandão de Carvalho Lira RN MsN PhD 《Journal of clinical nursing》2018,27(1-2):e195-e202
124.
Casali G Luzi G Vicchio M della Monica PL Minardi G Musumeci F 《Asian cardiovascular & thoracic annals》2008,16(3):208-211
The aim of this study was to evaluate midterm echocardiographic results and changes in quality of life after aortic valve replacement with 17-mm St. Jude Medical Regent mechanical prostheses in patients with aortic valve stenosis. The study population was 34 women and 2 men, aged 31-83 years. Echocardiographic follow-up was 100% complete at 4.1 +/- 1.8 years. Hospital mortality was 5.6%. Actuarial 5-year survival was 88.5% +/- 0.067%. Postoperative echocardiography showed significant regression of left ventricular mass index and significant reductions of peak gradient, mean gradient and mean effective orifice area index. All survivors were interviewed using the 36-item Short Form Health Survey questionnaire. Scores obtained in 7 of the 8 domains of the test were significantly higher than preoperative values. In our experience, implantation of this prosthesis allowed regression of left ventricular mass index and improved the perceived quality of life. 相似文献
125.
Colonic tuberculosis 总被引:1,自引:0,他引:1
Villanueva Sáenz E Martínez Hernández Magro P Fernando Alvarez-Tostado Fernández J Valdés Ovalle M 《Digestive diseases and sciences》2002,47(9):2045-2048
Tubercle bacillus was discovered in 1882 by Robert Koch. With the introduction of chemotherapy for tuberculosis in the 1940s the incidence of this entity decreased. The incidence of the tuberculosis of the colon began to increase at the 1980s with the rise in numbers of patients considered as high risk for this entity, such as HIV-infected individuals, patients with chronic renal disease, and immunosuppressed patients with prolonged steroid therapy. We report on two patients with history of chronic abdominal pain and weight loss with a palpable mass in the right lower quadrant. In one patient chest radiography revealed a miliary reticulonodular pattern. In both, abdominal CT scan showed retroperitoneal lymphadenopathy and colonic wall thickness. Colonoscopic examination showed ulcerative lesions and ileocecal valve disruption. Microscopic examination of intestinal content showed evidenced M. tuberculosis. Tuberculosis of the colon should be suspected in patients suffering from chronic abdominal pain and weight loss. 相似文献
126.
Damian Craiem Mariano E. Casciaro Sebastian Graf Carolina E. Glaser Enrique P. Gurfinkel Ricardo L. Armentano 《Cardiovascular Engineering》2009,9(4):127-133
The geometry of coronary arteries affects regional atherogenic processes. Accurate images can be assessed using multislice
computer tomography (MSCT) to estimate bifurcations angles. We propose a three-dimensional (3D) method to measure true bifurcation
angles of coronary arteries and to determine possible correlations between plaque presence and angulations. The left main
(LM) coronary artery, left anterior descendent (LAD) and left circumflex artery (LCX) were imaged in 40 atherosclerotic and
35 healthy patients, using 64-rows MSCT. This Y-junction was simplified fitting a 3D cylinder to each vessel to estimate true
bifurcation angles and diameters. The method was tested in phantoms and interobserver variability was assessed. Geometrical
results were compared between groups using an unpaired t-test. The cylinders fitted reasonably well with mean distances to measured points below 0.4 mm. LAD–LCX bifurcation angles
were wider in the atherosclerotic group (p < 0.01). LAD (p < 0.01) and LCX (p < 0.05) diameters were also larger. In phantoms mean absolute difference between true and estimated angles (N = 27) was 0.44 ± 0.54°. Interobserver mean difference (N = 135) was 1.8 ± 5.8°. Simplifying coronary bifurcation with cylinders results in a reliable technique to assess coronary
artery geometry in 3D, avoiding planar projections and decreasing interobserver variability. Geometrical risk factors should
be incorporated to properly predict atherosclerosis processes. 相似文献
127.
Ruiz-Argüelles GJ López-Martínez B Valdés-Tapia P Gómez-Rangel JD Reyes-Núñez V Garcés-Eisele J 《American journal of hematology》2005,78(1):21-26
Over a 36-month period, 46 consecutive Mexican mestizos with a clinical marker associated with a primary hypercoagulable state were prospectively assessed by searching for the sticky platelet syndrome (SPS), the activated protein C resistance (aPCR) phenotype, coagulation protein C activity and antigen, coagulation protein S, antithrombin III, plasminogen, tissue-type plasminogen activator activity, plasminogen activator inhibitor activity, plasminogen activator inhibitor type 1, IgG and IgM isotypes of antiphospholipid antibodies, homocysteine levels, the factor V gene Leiden, Cambridge, Hong Kong, and Liverpool mutations, the 677 C-->T mutation in the 5,10-methylenetetrahydrofolatereductase (MTHFR), and the G20210A polymorphism in the 3'-untranslated region of the prothrombin gene. Of the 46 consecutive patients prospectively accrued in the study, only 12 (26%) were males, the median age being 38 years (range 10-63 years). In only four individuals (8%) could we not record any abnormality. In 5/42 patients with abnormal results (12%), a single abnormality was recorded, whereas in the remaining 37, two to five co-existing abnormalities were identified. We found 22 (48%) patients with the SPS, 11 (24%) with the aPCR phenotype, 5 (11%) with the factor V Leiden mutation, 7 (15%) with the prothrombin gene mutation, 29 (63%) with the MTHFR gene mutation, 11 (24%) with the factor V HR2 haplotype, 11 (24%) with antiphospholipid antibodies, 4 (9%) with PS deficiency, 6 (13%) with PC deficiency, one with the FV Hong Kong mutation, and one with AT-III deficiency. The results are consonant with the idea that most cases of thrombophilia in Mexico are multifactorial. 相似文献
128.
129.
Pablo Lozano Marta Pea Mariano Herrero-Climent Jose Vicente Rios-Santos Blanca Rios-Carrasco Aritza Brizuela Javier Gil 《Materials》2022,15(4)
The procedure generally used to remove bacterial biofilm adhering to the surface of titanium on dental implants is implantoplasty. This treatment is based on the machining of the titanium surface to remove bacterial plaque. In this study, we used 60 grade 4 titanium implants and performed the implantoplasty protocol. Using X-ray diffraction, we determined the stresses accumulated in each of the as-received, machined and debris implants. The resistance to corrosion in open circuit and potentiodynamically in physiological medium has been determined, and the corrosion potentials and intensities have been determined. Tests have been carried out to determine ion release by ICP-MS at different immersion times. The results show that the corrosion resistance and the release of titanium ions into the medium are related to the accumulated energy or the degree of deformation. The titanium debris exhibit compressive residual stresses of −202 MPa, the implant treated with implantoplasty −120 MPa, and as-received −77 MPa, with their corrosion behavior resulting in corrosion rates of 0.501, 0.77, and 0.444 mm/year, respectively. Debris is the material with the worst corrosion resistance and the one that releases the most titanium ions to the physiological medium (15.3 ppb after 21 days vs. 7 ppb for as-received samples). Pitting has been observed on the surface of the debris released into the physiological environment. This behavior should be taken into account by clinicians for the good long-term behavior of implants with implantoplasty. 相似文献
130.
Mariano Rocchi Angela Covone Giovanni Romeo Raffaella Faraonio Vittorio Colantuoni 《Somatic Cell and Molecular Genetics》1989,15(2):185-190
The human gene coding for RBP4 has been assigned to 10q2324 using a panel of somatic cell hybrids and in situ hybridization experiments. The mapping of the human RBP1, previously assigned by our group to chromosome 3 using a panel of somatic cell hybrids, was restricted to the region 3q2122 using in situ experiments and Southern blots of genomic DNA from a hybrid retaining a portion of chromosome 3.R.F. is recipient of a Research Grant from A.I.R.C. 相似文献