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81.
82.
Journal of Thrombosis and Thrombolysis - There is no strong evidence on pharmacogenetics role on the quality of INR control after the initiation phase and on the maintenance of stable INR on the...  相似文献   
83.

BACKGROUND

Malignant fibrous histiocytoma, a subtype of primary lung sarcoma is a very rare disease. It usually presents as a lung nodules and the final diagnosis is made by immunohistochemical studies.

METHODS

A 45-year-old patient presented with progressive dyspnea, dry cough and right shoulder pain. Chest X-ray revealed complete opacification of the right hemithorax. Chest computed tomography confirmed the presence of a heterogeneous lesion occupying the whole right hemithorax causing a mass effect on the trachea. Ultrasound guided biopsy was done and final pathology was suggestive of malignant fibrous histiocytoma.

CONCLUSION

Progressive dyspnea in young otherwise healthy patients should be investigated early on. In our case the presence of right shoulder pain indicates advance disease illustrated by the singular imaging findings.  相似文献   
84.
The majority of patients with temporal lobe epilepsy (TLE) experience disturbances of episodic memory from structural damage or dysfunction of the hippocampus. The objective of this study was to use functional Magnetic Resonance Imaging (fMRI) to identify regions where resting state connectivity to the left hippocampus (LH) is correlated with neuropsychological measures of verbal memory retention in TLE patients. Eleven left TLE (LTLE) patients and 15 control subjects participated in resting state fMRI scans. All LTLE patients underwent neuropsychological testing. Resting state functional connectivity maps to the LH were calculated for each patient, and subsequently used in a multiple regression analysis with verbal memory retention scores as a covariate. The analysis identified brain regions whose connectivity to the LH was linearly related to memory retention scores across the group of patients. In LTLE patients, right sided (contralateral) clusters in the precuneus and inferior parietal lobule (IPL) exhibited increased connectivity to the LH with increased memory retention score; left sided (ipsilateral) regions in the precuneus and IPL showed increased connectivity to the LH with decreased retention score. Patients with high memory retention scores had greater connectivity between the LH–right parietal clusters than between the LH–left parietal clusters; in contrast, control subjects had significantly and consistently greater LH–left hemisphere than LH–right hemisphere connectivity. Our results suggest that increased connectivity in contralateral hippocampal functional pathways within the episodic verbal memory network represents a strengthening of alternative pathways in LTLE patients with strong verbal memory retention abilities. Hum Brain Mapp 35:735–744, 2014. © 2012 Wiley Periodicals, Inc.  相似文献   
85.
We recruited 103 families from Jordan with neurodevelopmental disorders (NDD) and patterns of inheritance mostly suggestive of autosomal recessive inheritance. In each family, we investigated at least one affected individual using exome sequencing and an in-house diagnostic variant interpretation pipeline including a search for copy number variation. This approach led us to identify the likely molecular defect in established disease genes in 37 families. We could identify 25 pathogenic nonsense and 11 missense variants as well as 3 pathogenic copy number variants and 1 repeat expansion. Notably, 11 of the disease-causal variants occurred de novo. In addition, we prioritized a homozygous frameshift variant in PUS3 in two sisters with intellectual disability. To our knowledge, PUS3 has been postulated only recently as a candidate disease gene for intellectual disability in a single family with three affected siblings. Our findings provide additional evidence to establish loss of PUS3 function as a cause of intellectual disability.  相似文献   
86.
87.

Introduction

Vertical root fracture is a common finding in endodontically treated teeth, notably oval roots. The aim of the present study was to determine the effect of instrumentation kinematics and the material of instrument construction of single-file systems on dentin walls and fracture resistance of oval roots.

Methods

Sixty-five roots with oval canals were allocated into a control group (n = 5) and 3 experimental groups of 20 roots each. Group WO was instrumented with the WaveOne primary file (Dentsply Maillefer, Baillagues, Switzerland), group PT-Rec was prepared with F2 ProTaper files (Dentsply Maillefer, Baillagues, Switzerland) used in a reciprocating motion, and group PT-Rot was prepared with F2 ProTaper files used in a rotation motion. For crack evaluation, half of the samples (n = 30) were embedded in acrylic resin, and the blocks were sectioned at 3, 6, and 9 mm from the apex. The sections were examined under a stereomicroscope and scored for crack presence. The other half of the specimens (n = 30) were obturated using lateral condensation of gutta-percha and AdSeal sealer (Meta Biomed Co, Ltd, Chungbuk, Korea). The specimens were then subjected to a load of 1 mm/min to determine the force required to fracture the roots.

Results

WaveOne instruments induced the least amount of cracks and exhibited greatest resistance to fracture compared with ProTaper F2 files whether used in reciprocating or rotating motions.

Conclusions

The alloy from which the material is manufactured is a more important factor determining the dentin damaging potential of single-file instruments than the motion of instrumentation.  相似文献   
88.

Objectives

of this review is to inform practitioners with the most updated information on tissue engineering and its potential applications in dentistry.

Data

The authors used “PUBMED” to find relevant literature written in English and published from the beginning of tissue engineering until today. A combination of keywords was used as the search terms e.g., “tissue engineering”, “approaches”, “strategies” “dentistry”, “dental stem cells”, “dentino-pulp complex”, “guided tissue regeneration”, “whole tooth”, “TMJ”, “condyle”, “salivary glands”, and “oral mucosa”.

Sources

Abstracts and full text articles were used to identify causes of craniofacial tissue loss, different approaches for craniofacial reconstructions, how the tissue engineering emerges, different strategies of tissue engineering, biomaterials employed for this purpose, the major attempts to engineer different dental structures, finally challenges and future of tissue engineering in dentistry.

Study selection

Only those articles that dealt with the tissue engineering in dentistry were selected.

Conclusions

There have been a recent surge in guided tissue engineering methods to manage periodontal diseases beyond the traditional approaches. However, the predictable reconstruction of the innate organisation and function of whole teeth as well as their periodontal structures remains challenging. Despite some limited progress and minor successes, there remain distinct and important challenges in the development of reproducible and clinically safe approaches for oral tissue repair and regeneration. Clearly, there is a convincing body of evidence which confirms the need for this type of treatment, and public health data worldwide indicates a more than adequate patient resource. The future of these therapies involving more biological approaches and the use of dental tissue stem cells is promising and advancing. Also there may be a significant interest of their application and wider potential to treat disorders beyond the craniofacial region.

Clinical Significance

Considering the interests of the patients who could possibly be helped by applying stem cell-based therapies should be carefully assessed against current ethical concerns regarding the moral status of the early embryo.  相似文献   
89.
In this report, we describe a case of a 43-year-old male who sustained a displaced mid chondral costal cartilage fracture along with multiple ipsilateral rib fractures following a jet ski collision. Costal cartilage fractures (CC) are commonly missed on imaging evaluation, and accordingly underreported in the literature. High-energy blunt chest trauma represents the most common mechanism for CC injuries. Computed Tomography (CT) is the modality of choice to diagnose CC fractures along with the associated cardiopulmonary and abdominal injuries in polytrauma patients. There is currently no consensus with respect to the management of CC fractures. Further research is required to explore the long-term impact of CC fractures on thoracic cage stability.  相似文献   
90.
In Lebanon and many other countries where structures are vulnerable to impact loads caused by accidental rock falls due to landslides, specifically bridges with hollow core slab, it is mandatory to develop safe and efficient design procedures to design such types of structures to withstand extreme cases of loading. The structural response of concrete members subjected to low velocity high falling weight raised the interest of researchers in the previous years. The effect of impact due to landslide falling rocks on reinforced concrete (RC) slabs has been investigated by many researchers, while very few studied the effect of impact loading on pre-stressed structures, noting that a recent study was conducted at Beirut Arab University which compared the dynamic behavior of reinforced concrete and post-tensioned slabs under impact loading from a 605 kg impactor freely dropped from a height of 20 m. Hollow core slabs are widely used in bridges and precast structures. Thus, studying their behavior due to such hazards becomes inevitable. This study focuses on these types of slabs. For a better understanding of the behavior, a full scale experimental program consists of testing a single span hollow core slab. The specimen has 6000 mm × 1200 mm × 200 mm dimensions with a 100 mm cast in a place topping slab. Successive free fall drops cases from 14 m height will be investigated on the prescribed slab having a span of 6000 m. This series of impacts will be held by hitting the single span hollow core slab at three different locations: center, edge, and near the support. The data from the testing program were used to assess the structural response in terms of experimental observations, maximum impact and inertia forces, structural damage/failure: type and pattern, acceleration response, and structural design recommendations. This research showed that the hollow core slab has a different dynamic behavior compared to the post tensioned and reinforced concrete slabs mentioned in the literature review section.  相似文献   
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