全文获取类型
收费全文 | 5132篇 |
免费 | 397篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 167篇 |
妇产科学 | 124篇 |
基础医学 | 742篇 |
口腔科学 | 90篇 |
临床医学 | 450篇 |
内科学 | 1158篇 |
皮肤病学 | 109篇 |
神经病学 | 495篇 |
特种医学 | 121篇 |
外科学 | 502篇 |
综合类 | 37篇 |
一般理论 | 2篇 |
预防医学 | 455篇 |
眼科学 | 130篇 |
药学 | 443篇 |
中国医学 | 12篇 |
肿瘤学 | 448篇 |
出版年
2024年 | 8篇 |
2023年 | 87篇 |
2022年 | 116篇 |
2021年 | 284篇 |
2020年 | 162篇 |
2019年 | 183篇 |
2018年 | 227篇 |
2017年 | 146篇 |
2016年 | 187篇 |
2015年 | 179篇 |
2014年 | 258篇 |
2013年 | 301篇 |
2012年 | 444篇 |
2011年 | 424篇 |
2010年 | 235篇 |
2009年 | 203篇 |
2008年 | 327篇 |
2007年 | 337篇 |
2006年 | 263篇 |
2005年 | 249篇 |
2004年 | 191篇 |
2003年 | 166篇 |
2002年 | 134篇 |
2001年 | 43篇 |
2000年 | 41篇 |
1999年 | 30篇 |
1998年 | 27篇 |
1997年 | 24篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 15篇 |
1992年 | 22篇 |
1991年 | 20篇 |
1990年 | 14篇 |
1989年 | 16篇 |
1988年 | 13篇 |
1987年 | 14篇 |
1986年 | 16篇 |
1985年 | 14篇 |
1984年 | 7篇 |
1980年 | 6篇 |
1979年 | 14篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1974年 | 13篇 |
1973年 | 9篇 |
1971年 | 5篇 |
1934年 | 5篇 |
排序方式: 共有5562条查询结果,搜索用时 31 毫秒
1.
Oliveira Gonalves Ana Sofia Panteli Dimitra Neeb Lars Kurth Tobias Aigner Annette 《The European journal of health economics》2022,23(1):47-57
The European Journal of Health Economics - The aims of this study were to assess whether there is a conceptual overlap between the questionnaires HIT-6 and EQ-5D and to develop a mapping algorithm... 相似文献
2.
3.
Jennifer Wang Jonathan G. Stine Scott L. Cornella Curtis K. Argo Steven M. Cohn 《临床与转化肝病杂志(英文版)》2015,3(4):254-259
Background and Aims: Gastric antral vascular ectasia (GAVE) is commonly found in patients with cirrhosis, but it is also associated with other diseases in the absence of cirrhosis. Whether GAVE confers a different severity of gastrointestinal (GI) bleeding between patients with and without cirrhosis remains unknown. We aim to examine whether there is a difference in clinically significant GI bleeding due to GAVE in patients with or without cirrhosis. Methods: This is a retrospective case-control study of patients who were diagnosed with GAVE between January 2000 and June 2014. Patients were categorized into cirrhosis and noncirrhosis groups, and those with an additional GI bleeding source were excluded. Univariate comparisons and multivariable models were constructed using logistic regression. Results: In total, 110 patients diagnosed with GAVE on esophagogastroduodenoscopy (EGD) were included in our analysis; 84 patients had cirrhosis (76.4%) and 26 (23.6%) did not. Active GI bleeding was more prevalent in patients without cirrhosis (63.4% vs. 32.1%, p=0.003) despite similar indications for EGD, and endoscopic treatment with argon plasma coagulation (APC) was required more often in this group, approaching statistical significance (27% vs. 10.7%, p=0.056). There was no difference in bleeding severity, as evidenced by similar re-bleeding rates, surgery, or death attributed to uncontrolled bleeding. The strongest independent risk factor for GI bleeding was the absence of cirrhosis (odds ratio (OR): 5.151 (95% confidence interval (CI): 1.08-24.48, p=0.039). Conclusions: Patients with GAVE in the absence of cirrhosis are at higher risk for active GI bleeding and require more frequent endoscopic treatment than similar patients with cirrhosis. It may be worthwhile to treat GAVE in this population even in the absence of active bleeding. 相似文献
4.
5.
Jorge Guardado Carlos Cotrim Otília Sim?es Sofia Almeida Mário Ialá Luís Lopes Hélder Pereira Manuel Carrageta 《Revista portuguesa de cardiologia》2006,25(4):409-415
INTRODUCTION: Transesophageal echocardiography (TEE) has become increasingly useful in the study of patients with suspected pulmonary thromboembolism. OBJECTIVE: The aim of this study was to prospectively evaluate the usefulness of TEE in the study of the distal part of the left pulmonary artery (LPA) as well as the influence of this procedure on total echocardiographic exam duration. METHODOLOGY: A prospective study in two groups of consecutive patients referred for TEE with a one- year interval between evaluation of Group A: 33 patients, 17 male, mean age 54 +/- 24 years, and Group B: 42 patients, 20 male, mean age 48 +/- 27 years (p = NS). The procedure was considered long when it took more than 3 min to evaluate the distal part of the LPA. RESULTS: In group A we were able to visualize the distal part of the LPA in 24 patients (73%) without significant prolongation of total exam duration in 16 patients (48% of group A). In one of the patients with suspected pulmonary thromboembolism thrombi were only observed in the distal part of the LPA. In group B we were able to visualize the distal part of the LPA in 36 patients (86%) without significant prolongation of total exam duration in 26 patients (61% of group B). CONCLUSIONS: 1. Visualization of the distal part of the LPA was possible in more patients, and with TEE time prolongation in less patients, in group B. These differences can be accounted for by the training of the operator in this technique. 2. The importance of visualization of this part of the LPA in guiding treatment in the subset of patients with pulmonary thromboembolism confirms the usefulness of this specific procedure. 相似文献
6.
Ignacio Alvarez Alvarez M.D. Pedro Sanchez Lazo Ph.D. Sofia Ramos Gonzalez Ph.D. J. Pablo Rodrigo Tapia M.D. Faustino Nunez Batalla M.D. Carlos Suarez Nieto M.D. 《American journal of otolaryngology》1997,18(6):375
Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV. 相似文献
7.
George E. Fryer PhD Curtis Stine MD Richard D. Krugman MD Thomas J. Miyoshi 《The Journal of rural health》1994,10(3):193-198
The performance of area health education center (AHEC)-stimulated programs and decentralized education for medicine is not well understood. The Statewide Education Activities for Rural Colorado's Health (SEARCH)/AHEC project at the University of Colorado School of Medicine was examined to determine if the program had an effect on the practice location of its graduates. Practice location and specialty of graduates of the University of Colorado School of Medicine (UCSOM) classes 1980-1985 were compared for students who had participated in decentralized SEARCH/AHEC experiences versus students who had not. The majority of the graduates were practicing out of state in 1990. Non-Colorado doctors were more often practicing in rural (non-metropolitan statistical area [MSA]) counties and in towns of fewer than 2,500, 5,000 and 10,000 residents, respectively. In addition, of the 251 active patient care physicians practicing in Colorado communities of fewer than 10,000 in non-MSA counties in 1986, those who precepted UCSOM students on SEARCH rotations were more likely to have remained in their same practice location in 1992 (77.8% versus 62.1% for those who had not precepted students). This analysis of both student and preceptor practice patterns documents the value of decentralized medical education in addressing the geographic and specialty maldistribution of physicians. These results have important policy implications for funding medical education programs. 相似文献
8.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献
9.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
10.
Sofia I. Andrikoula Haris S. Vasiliadis Anastasios V. Tokis Paraskevi Kosta Anna Batistatou Anastasios D. Georgoulis 《Arthroscopy》2007
Intra-articular ganglia are rare and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. We present 4 cases of intra-articular ganglion cysts associated with the anterior cruciate ligament (ACL) in 3 patients. The most commonly occurring symptoms were pain aggravated after stressing activities and limited knee range of motion. In 1 patient, ganglion cysts appeared in both knees with a time difference of 1 year. An MRI revealed typical signs of ganglion cysts in the substance of the ACL. Arthroscopy was performed for further evaluation and treatment. Histologic examination of the tissue removed revealed the presence of features consistent with ganglion cysts. Therefore, in the case of chronic knee discomfort with nonspecific clinical signs and symptoms and without a clear cause, an intra-articular ganglion cyst should be considered as causing pathology. An MRI is the most sensitive and specific method for diagnosis. However, the relatively slow progression of symptoms may delay the patient’s decision to seek medical attention. Delayed diagnosis makes arthroscopic total resection of the ganglion technically demanding or not possible at all, and extensive debridement of the ACL may be required. 相似文献