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991.
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BACKGROUND: After ankle sprain, there can be many causes of disability, the origins of which cannot be determined using standard diagnostic tools. HYPOTHESIS: Ankle arthroscopy is a useful tool in identifying intra-articular disorders of the talocrural joint in cases of residual ankle disability after sprain. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: The authors gathered the independent diagnostic results of physical examination, standard mortise and lateral radiography, stress radiography of the talocrural joint, and magnetic resonance imaging for 72 patients with residual ankle disability lasting more than 2 months after injury (mean, 7 months after injury). They performed arthroscopic procedures and compared the double-blind results. RESULTS: In all cases, the arthroscopic results matched those of other means of diagnosis. In 14 cases, the arthroscopic approach exceeded the capabilities of the other methods. Including duplications, 39 patients (54.2%) had anterior talofibular ligament injuries, 17 patients (23.6%) had distal tibiofibular ligament injuries, 29 patients (40.3%) had osteochondral lesions, 13 patients (18%) had symptomatic os subfibulare, 3 patients (4.2%) had anterior impingement exostosis, and 3 patients (4.2%) had impingement due to abnormally fibrous bands. There were only 2 cases in which the cause of symptoms could not be detected by ankle arthroscopy, compared with 16 cases in which the cause of disability could not be detected using standard methods. In 3 cases (17.6%) of distal tibiofibular ligament injuries, 8 cases (27.6%) of osteochondral lesions, and all 3 cases (100%) of impingement of an abnormal fibrous band, ankle arthroscopy was the only method capable of diagnosing the cause of residual ankle pain after a sprain. CONCLUSION: The present results suggest that arthroscopy can be used to diagnose the cause of residual pain after an ankle sprain in most cases that are otherwise undiagnosable by clinical examination and imaging study.  相似文献   
993.
OBJECTIVE: To evaluate the in vivo therapeutic effect of pioglitazone, a peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, on the development of lesions in a guinea pig model of osteoarthritis (OA), and to determine the influence of pioglitazone on the synthesis of matrix metalloproteinase 13 (MMP-13) and interleukin-1beta (IL-1beta) in articular cartilage. METHODS: The OA model was created by partial medial meniscectomy of the right knee joint. The guinea pigs were divided into 4 treatment groups: unoperated animals that received no treatment (normal), operated animals (OA guinea pigs) that received placebo, OA guinea pigs that received oral pioglitazone at 2 mg/kg/day, and OA guinea pigs that received oral pioglitazone at 20 mg/kg/day. The animals began receiving medication 1 day after surgery and were killed 4 weeks later. Macroscopic and histologic analyses were performed on the cartilage. The levels of MMP-13 and IL-1beta in OA cartilage chondrocytes were evaluated by immunohistochemistry. RESULTS: OA guinea pigs treated with the highest dosages of pioglitazone showed a significant decrease, compared with the OA placebo group, in the surface area (size) and grade (depth) of cartilage macroscopic lesions on the tibial plateaus. The histologic severity of cartilage lesions was also reduced. A significantly higher percentage of chondrocytes in the middle and deep layers stained positive for MMP-13 and IL-1beta in cartilage from placebo-treated OA guinea pigs compared with normal controls. Guinea pigs treated with the highest dosage of pioglitazone demonstrated a significant reduction in the levels of both MMP-13 and IL-1beta in OA cartilage. CONCLUSION: This is the first in vivo study demonstrating that a PPARgamma agonist, pioglitazone, could reduce the severity of experimental OA. This effect was associated with a reduction in the levels of MMP-13 and IL-1beta, which are known to play an important role in the pathophysiology of OA lesions.  相似文献   
994.
TS-1/CPT-11 combination therapy was carried out in a case of advanced gastric cancer with liver and lymph node metastases and obstructive jaundice after percutaneous transhepatic cholangio drainage (PTCD). Regression of the primary carcinoma and reduction in size of metastases were observed. Grade 1 fatigue and grade 2 neutropenia were noted as adverse reactions to the treatment. TS-1/CPT-11 combination therapy was useful in this case of advanced gastric cancer with liver and lymph node metastases.  相似文献   
995.
Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) by positron emission tomography (PET) with oxygen-15 labelled carbon dioxide (C15O2) or 15O-labelled water (H2 15O), 15O-labelled carbon monoxide (C15O) and 15O-labelled oxygen (15O2) is useful for diagnosis and treatment planning in cases of cerebrovascular disease. The measured values theoretically depend on various factors, which may differ between PET centres. This study explored the applicability of a database of 15O-PET by examining between-centre and within-centre variation in values. Eleven PET centres participated in this multicentre study; seven used the steady-state inhalation method, one used build-up inhalation and three used bolus administration of C15O2 (or H2 15O) and 15O2. All used C15O for measurement of CBV. Subjects comprised 70 healthy volunteers (43 men and 27 women; mean age 51.8±15.1 years). Overall mean±SD values for cerebral cortical regions were: CBF=44.4±6.5 ml 100 ml–1 min–1; CBV=3.8±0.7 ml 100 ml–1; OEF=0.44±0.06; CMRO2=3.3±0.5 ml 100 ml–1 min–1. Significant between-centre variation was observed in CBV, OEF and CMRO2 by one-way analysis of variance. However, the overall inter-individual variation in CBF, CBV, OEF and CMRO2 was acceptably small. Building a database of normal cerebral haemodynamics obtained by the15O-PET methods may be practicable.  相似文献   
996.
As with other cranial nerves and many CNS neurons, primary auditory neurons degenerate as a consequence of loss of input from their target cells, the inner hair cells (IHCs). Electrical stimulation (ES) of spiral ganglion cells (SGCs) has been shown to enhance their survival. Glial cell line-derived neurotrophic factor (GDNF) has also been shown to increase survival of SGCs following IHC loss. In this study, the combined effects of the GDNF transgene delivered by adenoviral vectors (Ad-GDNF) and ES were tested on SGCs after first eliminating the IHCs. Animal groups received Ad-GDNF or ES or both. Ad-GDNF was inoculated into the cochlea of guinea pigs after deafening, to overexpress human GDNF. ES-treated animals were implanted with a cochlear implant electrode and chronically stimulated. A third group of animals received both Ad-GDNF and ES (GDNF/ES). Electrically evoked auditory brainstem responses were recorded from ES-treated animals at the start and end of the stimulation period. Animals were sacrificed 43 days after deafening and their ears prepared for evaluation of IHC survival and SGC counts. Treated ears exhibited significantly greater SGC survival than nontreated ears. The GDNF/ES combination provided significantly better preservation of SGC density than either treatment alone. Insofar as ES parameters were optimized for maximal protection (saturated effect), the further augmentation of the protection by GDNF suggests that the mechanisms of GDNF- and ES-mediated SGC protection are, at least in part, independent. We suggest that GDNF/ES combined treatment in cochlear implant recipients will improve auditory perception. These findings may have implications for the prevention and treatment of other neurodegenerative processes. .  相似文献   
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999.
TLR4 and RP105 are unique members of the Toll-like receptor (TLR) family molecules. They are associated with small molecules called MD-2 and MD-1, respectively, to form heterodimers (TLR4/MD-2 and RP105/MD-1) and function as recognition/signaling molecules of lipopolysaccharide (LPS), a membrane component of Gram-negative bacteria. Analysis of transfectant cell lines and gene-targeted mice revealed that both MD-2 and MD-1 are involved in the recognition of LPS as well as in the regulation of intracellular distribution and the surface expression of TLR4 and RP105, respectively. Since RP105 or MD-1-deficient mice show a reduced but not complete lack of LPS responsiveness, there may be functional associations between TLR4/MD-2 and RP105/MD-1. In addition, there was an increased frequency of RP105-negative B-lymphocytes in the peripheral blood in several rheumatic diseases, such as systemic lupus erythematosus, suggesting the involvement of RP105 in the pathophysiology of autoimmunity. Further analysis of the structure and function of TLR4/MD-2 and RP105/MD-1 will provide a better understanding of the pathophysiology, and a chance to develop evidence-based treatments for septic shock syndrome and autoimmunity.  相似文献   
1000.
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