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101.
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This is the first report of a patient with venous insufficiency following compressive arachnoiditis ossificans (AO). Symptoms of fluctuating monoplegia and sensory disturbance appeared monthly, lasting several weeks each time. Spinal magnetic resonance imaging (MRI) showed high T2-weighted signal intensity in the posterior portion of the column from T11 to T12 and an intradural lesion with low T2-weighted signal intensity. Neurological function and MRI improved markedly following an operation on AO. The symptoms seen in the present case were due to posterior venous insufficiency following compressive AO.  相似文献   
104.
The pattern of subchondral bone density has been considered to reflect the stress distribution that occurs under physiologic loading conditions. To determine the force distribution through the wrist joint with Kienb?ck's disease in living subjects, we applied a computed tomography osteoabsorptiometry and investigated the subchondral bone density pattern across the radio-carpal joint of 6 normal subjects and 10 patients suffering from Kienb?ck's disease (Lichtman's stage IIIA, 5 patients; stage IIIB, 5 patients). A single density maximum was found in each scaphoid and lunate fossa in all normal subjects. Among the subjects with Kienb?ck's disease, the current analysis demonstrated that the density maximum area significantly increased in the scaphoid fossa and decreased in the lunate fossa from stage IIIA to IIIB group. These findings indicate that the load is shifted away from the lunate to the scaphoid with the progression of Kienb?ck's disease in living subjects.  相似文献   
105.
Vertebral decancellation for severe scoliosis   总被引:9,自引:0,他引:9  
STUDY DESIGN: The results of staged surgery including vertebral decancellation were reviewed retrospectively for 21 patients with severe scoliosis. OBJECTIVES: To evaluate the benefits and limitations of vertebral decancellation as new anterior surgical procedure. SUMMARY OF BACKGROUND DATA: The curvatures of severe scoliosis are often very rigid, and surgical correction using the anterior or posterior approach may not achieve the desired correction. Some studies reported neurologic complications might appear due to the aggressive approach or excessive correction force. METHODS: Twenty-one patients (average age, 17.0 years) with severe scoliosis, in whom Cobb angle was over 80 degrees (average angle, 107 degrees), underwent staged anterior and posterior spinal reconstruction. Vertebral decancellation was performed as anterior procedure, and until posterior instrumentation, halo traction was carried out. The transition of curvatures in coronal and sagittal planes was assessed in this series. RESULTS: The average correction rate of lateral curvature at the final follow-up was 46%. The average loss of correction was 2.5 degrees. Kyphosis, measured between T5 and T12, changed from 41 degrees to 36 degrees. Lordosis, measured between L1 and S1, changed from 56 degrees to 45 degrees. Transient neurologic deficit was seen in one case after vertebral decancellation. CONCLUSIONS: Staged surgery including vertebral decancellation is an effective surgical method for patients with severe scoliosis, where an inflexible rigid curve or the risk of occurrence of neurologic complications due to temporary correction may exist.  相似文献   
106.
Coracoacromial arch decompression in rotator cuff surgery   总被引:1,自引:0,他引:1  
In rotator cuff surgery it is important to obtain adequate decompression of the coracoacromial arch. However, it is difficult to localize the impingement site preoperatively. Based on histological and morphological studies and the clinical findings in 45 patients and 15 cadavers, we have tried to determine the impingement site. In addition, as a part of these investigations, we assessed the clinical outcome for 100 patients. Soft tissue decompression was indicated in 12 shoulders, anterior acromioplasty in 67 and anterior acromioplasty with coracoplasty in 21. According to Neer’s criteria there were 92 satisfactory and 8 unsatisfactory results. The mean postoperative UCLA score was 33.4 points and the results were rated excellent in 78, good in 18 and fair in 4.
Résumé  Dans la chirurgie de la coiffe des rotateurs, il est important d’obtenir une décompression adéquate sous-acromiale, mais il est difficile de localiser la zone de conflit avant l’opération. A partir d’études histologiques, morphologiques et des conclusions cliniques chez 45 malades et 15 cadavres, nous avons essayé de déterminer l’emplacement du conflit. De plus, nous avons évalué le résultat clinique de 100 cas. La décompression des parties molles était indiquée dans 12 épaules, l’acromioplastie antérieure dans 67 et l’acromioplastie antérieure avec coracoplastie dans 21 cas. D’après les critères de NEER, il y avait 92 résultats satisfaisants et 8 médiocres. Le score UCLA moyen postopératoire était à 33,4 points avec 78 résultats jugés excellents, 18 jugés bons, et 4 médiocres.


Accepted: 19 March 2000  相似文献   
107.
Vascularised fibular grafts. An experience of 102 patients   总被引:6,自引:0,他引:6  
The results and complications of 104 vascularised fibular grafts in 102 patients are presented. Bony union was ultimately achieved in 97 patients, with primary union in 84 (84%). The mean time to union was 15.5 weeks (8 to 40). In 13 patients, primary union was achieved at one end of the fibula and secondary union at the other end. In these patients, the mean time to union was 31.1 weeks (24 to 40). Five patients failed to achieve union, with a resultant pseudarthrosis (3 patients) or amputation (2 patients). There were various complications. Immediate thrombosis occurred in 14 cases. In two of 23 patients with osteomyelitis, infection recurred at two and six months after surgery, respectively. Both patients had active osteomyelitis less than one month before the operation. Bony infection occurred in a patient with a synovial sarcoma of the forearm one year after surgery. In 15 patients, 19 fractures of the fibular graft occurred after bony union, all except one within one year after union. In patients in whom an external fixator had been used, fracture occurred soon after its removal. Union was difficult to achieve in cases of congenital pseudarthrosis of the tibia. Appropriate alignment of the fibular graft is an important factor in preventing stress fracture. The vascularised fibula should be protected during the first year after union. Postoperative complications at the donor site included transient palsy of the superficial peroneal nerve in three patients, contracture of flexor hallucis longus in two and valgus deformity of the ankle in three. Vascularised fibular grafts are useful in the reconstruction of massive bony defects. We believe that meticulous preoperative planning, including choosing which vessels to select in the recipient and the type of fixation devices to use, and care in the introduction of the vascularised fibula, can improve the results and prevent complications.  相似文献   
108.
109.
The mechanism underlying hypertrophy of experimentally vascularized bone grafts was studied in 15-week-old rats. The segmental ulna was grafted to the tibial defect with an external fixator. In experiment 1, 24 rats were classified into four groups to evaluate conventional (non-vascularized), cuff (periosteum-encased, non-vascularized), and vascularized bone grafts, and vascularized segmental grafts with fracture. In experiment 2, 12 rats were classified into two groups according to the presence of mechanical loading. This involved vascularized bone grafts with external fixators, and vascularized bone grafts with external fixators removed after bone union. The bone dynamics of the grafts were investigated by several methods, including roentgenographic analysis, histologic studies, and fluorochrome labeling. In experiment 1, a slight bone formation was recognized in the conventional bone graft, while irregular bone formation with creeping substitution was observed in the cuff graft. The vascularized bone graft showed significant hypertrophy; hypertrophy of the vascularized bone with fracture was greater than that without fracture. In experiment 2, markedly circumferential bone formation was observed after removal of the external fixator, while slight new bone formation was observed during the late postoperative period in bone with an external fixator. These results suggest that hypertrophy can be promoted by artificial fracture of the grafted bone, and that mechanical loading is an important factor for remodeling of grafted bone.  相似文献   
110.
BACKGROUND: Taurine, a potent antioxidant, has been reported to improve streptozotocin-induced diabetes mellitus, in which the development of diabetes results from an attack by oxygen free radicals on pancreatic beta cells. However, taurine also increases the excretion of cholesterol via conversion to bile acid and would be expected to improve insulin resistance. OBJECTIVE: The effects of taurine on insulin sensitivity were examined in a model rat of insulin resistance and type 2 diabetes-the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. DESIGN: Male OLETF rats were divided into 2 groups at the age of 16 wk: a taurine-supplemented group and an unsupplemented group. As a nondiabetic control, Long-Evans-Tokushima-Otsuka rats were used. An oral-glucose-tolerance test and hyperinsulinemic euglycemic clamp were performed at the ages of 23 and 25 wk. RESULTS: The OLETF rats had hyperglycemia and insulin resistance and they had a greater accumulation of abdominal fat than did control rats. Abdominal fat accumulation, hyperglycemia, and insulin resistance were significantly lower in the taurine-supplemented group than in the unsupplemented group. Serum and liver concentrations of triacylglycerol and cholesterol were significantly higher in the OLETF rats than in the control rats and were significantly lower in the taurine-supplemented group than in the unsupplemented group, presumably because of the increased secretion of cholesterol into bile acid. Taurine-supplemented rats also showed higher nitric oxide secretion, evidenced by increased urinary excretion of nitrite. CONCLUSION: Taurine effectively improves metabolism in OLETF rats by decreasing serum cholesterol and triacylglycerol, presumably via increased secretion of cholesterol into bile acid and decreased production of cholesterol because of increased nitric oxide production.  相似文献   
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