全文获取类型
收费全文 | 43654篇 |
免费 | 3405篇 |
国内免费 | 362篇 |
专业分类
耳鼻咽喉 | 544篇 |
儿科学 | 1158篇 |
妇产科学 | 1122篇 |
基础医学 | 5506篇 |
口腔科学 | 735篇 |
临床医学 | 4734篇 |
内科学 | 9089篇 |
皮肤病学 | 934篇 |
神经病学 | 3115篇 |
特种医学 | 1371篇 |
外国民族医学 | 2篇 |
外科学 | 6008篇 |
综合类 | 1300篇 |
一般理论 | 43篇 |
预防医学 | 2944篇 |
眼科学 | 1794篇 |
药学 | 3295篇 |
中国医学 | 319篇 |
肿瘤学 | 3408篇 |
出版年
2023年 | 311篇 |
2022年 | 600篇 |
2021年 | 1140篇 |
2020年 | 733篇 |
2019年 | 943篇 |
2018年 | 1162篇 |
2017年 | 887篇 |
2016年 | 1013篇 |
2015年 | 1226篇 |
2014年 | 1640篇 |
2013年 | 1970篇 |
2012年 | 2808篇 |
2011年 | 2910篇 |
2010年 | 1663篇 |
2009年 | 1470篇 |
2008年 | 2335篇 |
2007年 | 2368篇 |
2006年 | 2338篇 |
2005年 | 2294篇 |
2004年 | 1991篇 |
2003年 | 1866篇 |
2002年 | 1693篇 |
2001年 | 1319篇 |
2000年 | 1254篇 |
1999年 | 1098篇 |
1998年 | 432篇 |
1997年 | 329篇 |
1996年 | 301篇 |
1995年 | 261篇 |
1994年 | 245篇 |
1993年 | 233篇 |
1992年 | 587篇 |
1991年 | 558篇 |
1990年 | 567篇 |
1989年 | 495篇 |
1988年 | 456篇 |
1987年 | 478篇 |
1986年 | 415篇 |
1985年 | 378篇 |
1984年 | 286篇 |
1983年 | 213篇 |
1982年 | 156篇 |
1981年 | 127篇 |
1980年 | 122篇 |
1979年 | 216篇 |
1978年 | 155篇 |
1976年 | 122篇 |
1975年 | 131篇 |
1973年 | 125篇 |
1972年 | 124篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Bibhuti B Das Linda B Pauliks Ole A Knudson Scott Kirby Kak-Chen Chan Lilliam Valdes-Cruz Raul O Cayre 《Journal of the American Society of Echocardiography》2005,18(3):231-236
We identified 18 patients with double-orifice mitral valve (DOMV) and intact atrioventricular (AV) septum out of 40,179 echocardiographic studies performed between 1997 and 2002 at Children's Hospital, Denver, CO. In this study we describe (1) the anatomic characteristics of the DOMV in the absence of AV septal defect, (2) the function of the mitral valve by spectral and color Doppler flow mapping, and (3) associated lesions. The topographic location of the orifices in the leaflets suggests possible embryologic mechanisms of DOMV. In this series, DOMV was most commonly associated with left-sided obstructive lesions (in 39% of patients). Spectral and color Doppler interrogation demonstrated a normal flow profile in most cases; only 2 patients had significant mitral regurgitation or stenosis. Therefore, due to the uncertain natural history of this lesion and the potential need for endocarditis prophylaxis, careful imaging of the mitral valve is recommended, particularly in the presence of left-sided obstructive lesions. 相似文献
82.
Philip Peng FRCPC Manon Choiniere PhD Dominique Dion MD MSc Howard Intrater FRCPC Sandra LeFort PhD Mary Lynch FRCPC May Ong FRCPC Saifee Rashiq MSc DA FRCPC Gregg Tkachuk PhD Yves Veillette FRCPC 《Journal canadien d'anesthésie》2007,54(12):977-984
PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment. 相似文献
83.
This study examines how acute hand injuries affect patients in their roles as spouse, caregiver, and/or worker. Qualitative data from patient interviews were used to analyze how these life roles were affected by the individuals' hand injuries. Data were extracted from interviews of three hand patients who had one or more roles of spouse, caregiver, and/or worker affected by their injury. Data were then examined and categorized for each life role by participant. Participants' views of how hand therapy affected their recovery and resumption of occupational role performance were also examined. Results showed that the participants expressed profound degrees of change in their ability to perform satisfactorily in their various life roles. 相似文献
84.
BACKGROUND: Increased autoantibody prevalence has been described in instances of high-dose exposure to polychlorinated biphenyls (PCBs). In 1996, an equipment malfunction at the Swan Hills Treatment Centre in Alberta, Canada, caused the release of gases containing PCBs into the ambient air. In view of the immune effects of PCBs and their potential as endocrine disruptors, we assessed autoantibody prevalence and looked for correlations with PCB levels. METHODS: Fifty-seven persons living within a 100 km radius of the waste treatment facility were assessed. Autoantibodies were measured by indirect immunofluorescence, double immunodiffusion, and immunoblotting. The levels of 26 congeners of PCBs were measured by gas chromatography and mass spectrometry. Provincial health records for physician visits and hospitalizations were reviewed for diagnoses of autoimmune disease. RESULTS: The prevalence of autoantibodies was 11% in the study participants and 0% in healthy controls. There was no correlation of PCB levels with autoantibody results. There was no associated increase in autoimmune disease noted on physician visits or hospitalizations. PCB levels were comparable to background levels reported for other populations. CONCLUSION: A correlation of titers of autoantibodies in the sera of individuals at risk and the blood levels of PCBs was not found, and the prevalence of autoantibodies in the at-risk group was not statistically different (p > .05) from that of an unexposed control group. The study group had higher titers of autoantibodies and some strong reactivity with intracellular antigens, but the significance of this observation may be understood only after long-term clinical assessments and follow-up. 相似文献
85.
Feng-Yuan Liu Chien-Yu Lin Joseph T Chang Shu-Hang Ng Shy-Chyi Chin Hung-Ming Wang Chun-Ta Liao Sheng-Chieh Chan Tzu-Chen Yen 《Journal of nuclear medicine》2007,48(10):1614-1619
Conventional work-up (CWU) with chest radiography, abdominal ultrasonography, and skeletal scintigraphy has limited value in M staging of nonkeratinizing nasopharyngeal carcinoma (NPC). Our aim was to evaluate whether (18)F-FDG PET could replace CWU by comparing their diagnostic efficacies. METHODS: Patients with histologically proven nonkeratinizing NPC and no prior treatment were prospectively enrolled. All study participants underwent CWU and (18)F-FDG PET for primary M staging. Distant metastasis was considered to be present if there was any reliable evidence identified within 1 y after diagnosis. The comparative diagnostic efficacies of (18)F-FDG PET, CWU, and the combination of (18)F-FDG PET and CWU (PET+CWU) were evaluated using the areas under the receiver-operating-characteristic (ROC) curves. RESULTS: Sixty-one (20.3%) of 300 eligible patients were found to have distant metastases. On a patient-based analysis, (18)F-FDG PET was found to be more effective than CWU (P < 0.001), whereas it was equally effective with PET+CWU (P = 0.130). On region-based analyses, (18)F-FDG PET was more effective than skeletal scintigraphy and chest radiography for detecting bone metastases (P < 0.001) and chest metastases (P < 0.001), respectively. (18)F-FDG PET and abdominal ultrasound were equally effective for detecting hepatic metastases (P = 0.127). On region-based analyses, the combination of (18)F-FDG PET and CWU did not yield any noticeable increase in diagnostic efficacy. CONCLUSION: (18)F-FDG PET can replace CWU in primary M staging of nonkeratinizing NPC. 相似文献
86.
Procalcitonin as a marker of bacterial infection in the emergency department: an observational study
Yi-Ling Chan Ching-Ping Tseng Pei-Kuei Tsay Shy-Shin Chang Te-Fa Chiu Jih-Chang Chen 《Critical care (London, England)》2003,8(1):R12
Introduction
Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients; its level is related to the severity of infection. We evaluated the value of PCT as a marker of bacterial infection for emergency department patients. 相似文献87.
88.
89.
90.
Improved survival rates for patients with major burn injuries and the consistent finding of significant long-term psychologic disability among survivors of burn trauma call for a redefinition of the role of the psychiatric consultant in the care of patients with burns. In addition to the traditional functions of diagnosis and treatment of discrete psychiatric disorders in patients with burns, this expanded role includes assisting the patient's normal process of psychologic adaptation after injury, assessing and managing burn pain, and facilitating communication among all members of the burn team. The functions of the psychiatrist are most effectively carried out when the psychiatrist is able to participate on a regular basis in the care of every patient as a member of the burn team. 相似文献