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Gleeson M 《British journal of nursing (Mark Allen Publishing)》2008,17(6):376-380
Nursing is a practice-based discipline and clinical practice is considered to be an integral part of nurse education. The pivotal role that preceptors play in the socialization, teaching and assessing of student nurses, is vital in helping students to integrate theory with practice. However, some evidence suggests that there can be minimal contact between the stakeholders involved in the students' education process, namely the university lecturers and preceptors. The focus of this article is on exploring the literature on models of support for student nurses with particular emphasis on the concept of preceptorship. 相似文献
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BACKGROUND: Baseline screening for lung cancer of 2968 high-risk men and women utilizing HRCT enrolled in ELCAP (Early Lung Cancer Action Project) was performed between 1993-2002. Among them, 65 people had surgical resection of their screen-diagnosed lung cancer, 53 of them on the basis of a diagnosis of malignancy or atypical bronchioloalveolar proliferation (ABP) on fine needle aspiration (FNA) biopsy at Weill Medical College of Cornell University (WMC) prior to surgery. The authors compared the diagnosis obtained from the FNA with the subsequent diagnosis from the surgical specimen to assess the reliability of a cytologic diagnosis of lung cancer on FNA of these screen-diagnosed lung cancers. METHODS: The FNA biopsies were performed with a 22-gauge Wescott needle by 1 radiologist (D.Y.), with preliminary on-site as well as final diagnosis rendered by a cytologist (M.V., J.K.). These results were correlated with histologic diagnoses obtained as a result of consensus diagnosis by a panel of 5 expert pulmonary pathologists. RESULTS: Of the 53 cases of lung cancer resected following FNA, 4 were diagnosed as atypical bronchioloalveolar proliferation (ABP), 14 as adenocarcinoma with bronchioloalveolar features (ADC-BAC), 28 as adenocarcinoma, not otherwise specified (ADC-NOS), 1 as squamous cell carcinoma (SQCC), 4 as nonsmall-cell carcinoma (NSCC), and 2 as typical carcinoid. In the 49 cases with a malignant cytology and 4 cases of ABP, lung cancer was confirmed histologically. The tumor sizes ranged from 4 mm to 40 mm, mean size 13mm. The final expert panel histologic diagnosis was adenocarcinoma in 47 cases; of these, 42 were invasive (mixed subtype or acinar subtype), and 5 were a noninvasive (bronchioloalveolar carcinoma, BAC). Three of the 42 invasive adenocarcinoma that had a predominant BAC component and 1 case of BAC were diagnosed as ABP on FNA; all were sampled at the periphery of the tumor. Three of 4 cases of invasive adenocarcinoma of high nuclear grade were diagnosed as NSCC, and 1 was inaccurately classified as SQCC on FNA. One case of high-grade noninvasive BAC associated with a scar was diagnosed as NSCC on FNA. Two cases classified as nonkeratinizing SQCC and 2 cases of large cell neuroendocrine carcinoma on histology were misclassified as ADC-NOS by FNA. Two cases of typical carcinoid on histology were also diagnosed as typical carcinoid on FNA. CONCLUSIONS: Preoperative diagnosis of lung cancer detected by screening with HRCT could be reliably made by FNA. Difficulty in classification occurs in carcinomas of high nuclear grade with prominent nucleoli, including poorly differentiated SQCC and large cell neuroendocrine carcinoma. These are best diagnosed as NSCC on cytomorphology with further subclassification based on immunohistochemistry, which these authors generally perform on cell-block material. A diagnosis of ABP on FNA may be indicative of noninvasive BAC or an invasive adenocarcinoma with prominent BAC features, usually sampled at its periphery. 相似文献
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Ferrara LA Gordon I Coquillette M Milks R Fleischman AJ Roy S Goel VK Benzel EC 《Journal of neurosurgery. Spine》2007,7(5):542-548
OBJECT: A preliminary in vitro biomechanical study was conducted to determine if the pressure at a bone graft-mortise interface and the load transmitted along a ventral cervical plate could be used as parameters to assess fusion status. METHODS: An interbody bone graft and a ventral plate were placed at the C3-4 motion segment in six fresh cadaveric goat spines. Polymethylmethacrylate (PMMA) was used to simulate early bone fusion at the bone graft site. The loads along the plate and the simultaneous pressures induced at the graft-endplate interfaces were monitored during simulated stages of bone healing. Each specimen was nondestructively tested in compression loading while the pressures and loads at the graft site were recorded continuously. Each specimen was tested under five conditions (Disc, Graft, Plate, PMMA, and Removal). RESULTS: The pressure at the interface of the bone graft and vertebral endplate did not change significantly with the addition of the ventral plate. The interface pressure and segmental stiffness did increase following PMMA augmentation of the bone graft (simulating an intermediate phase of bone fusion). The load transmitted along the ventral plate in compression increased after the addition of the bone graft, but decreased after PMMA augmentation. Thus, there was an increase in pressure at the graft-endplate interface and a decrease in load transferred along the ventral plate after the simulation of bone fusion. Upon removal of the ventral plate, the simulated fusion bore most of the axial load, thus explaining a further increase in graft site pressure. CONCLUSIONS: These observations support the notions of load sharing and the redistribution of loads occurring during and after bone graft incorporation. In the clinical setting, these parameters may be useful in the assessment of fusion after spine surgery. Although feasibility has been demonstrated in this preliminary study, further research is needed. 相似文献
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