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91.
Osteosarcoma of the head and neck is relatively rare and accounts for less than 10 percent of all osteosarcomas in general. We report a case of osteosarcoma in which imaging and histopathology of the hard palate of an 11-year-old boy yielded atypical findings. An approximately 8×15mm lesion found in the center of the palate was hard and healthy in color. Subsequent biopsy resulted in a diagnosis of nonepithelial malignant tumor. No abnormalities were observed in the maxillary bone or tooth on panoramic or occlusal radiographs. Computed tomography images revealed a mass lesion approximately 7×9×9mm in size on the hard palate extending into the maxilla. The cortex of the maxilla adjacent to the lesion was unclear in parts. The internal structures were slightly inhomogeneous and its density was lower than that of muscle. On magnetic resonance images, the lesion was represented by low signal intensity on T1-weighted (T1W) images and high signal intensity on T2-weighted images with fat-suppression. The margin of the lesion was a little unclear and the internal structures were slightly inhomogeneous. The lesion was enhanced homogeneously on post-contrast T1W images with fat-suppression. The histopathological diagnosis was fibrogenesis-type osteosarcoma. No findings specific to osteosarcoma such as localized enlargement of the periodontal ligament space alongside the root, cortical destruction, periosteal ossification or osteogenesis were found in this case.  相似文献   
92.
The origin of the peroneal intraneural ganglion and the outcome of treatment are still controversial. We report here three cases with peroneal intraneural ganglion and discuss the appropriate treatment. In our cases, 58-, 62-, and 65-year-old patients were operated on with extraneural decompression and epineurotomy within 4 months after onset of drop foot. Two cases demonstrated intraneural ganglion connecting to the articular branch and traversing to the deep and common peroneal nerve. At the 1-year follow-up, paralyzed peroneal nerve could be recovered in all patients even with residual ganglion. We propose correct early diagnosis, simple exoneural dissection, and atraumatic epineurotomy for the successful treatment of peroneal intraneural ganglion. Disruption of the stalk in the articular branch is a key point to prevent recurrence. For early diagnosis, clinicians should be aware of the existence of this rare lesion.  相似文献   
93.

Background

In 2012, the Kidney Disease: Improving Global Outcomes (KDIGO) updated the 2002 Kidney Disease Outcomes Quality Initiative (KDOQI) clinical practice guideline for chronic kidney disease (CKD). The 2012 KDIGO guideline elaborated the identification and prognosis of CKD by combining albuminuria with estimated glomerular filtration rate (eGFR). Identification of CKD with a high risk for a poor prognosis was investigated in human immunodeficiency virus (HIV)-infected individuals by applying the new guideline.

Methods

A total of 1,447 HIV-infected patients (1,351 male, 96 female; mean age 44.4 ± 11.5 years) were classified using a combination of eGFR and dipstick proteinuria, as a convenient alternative to albuminuria. Proteinuria was classified into 3 grades—(A1) – and +/? , (A2) 1+ and 2+ , and (A3) 3+ and 4+. eGFR was classified into 6 grades—(G1) ≤90, (G2) 60–89, (G3a) 45–59, (G3b) 30–44, (G4) 15–29, and (G5) <15 mL/min/1.73 m2.

Results

Mean CD4 cell count was 487 ± 214 /μL, with 80.7 % of patients having an undetectable HIV-RNA level. The prevalence of CKD stage ≤2 and stage ≥3 classified according to KDOQI staging was 93.4 and 6.6 %, respectively. Using the new KDIGO classification, the prevalence of CKD with either a low (green) or moderately increased (yellow) risk was 96.9 %, while the prevalence for a high (orange) and very high (red) risk was 3.1 %.

Conclusion

The use of the new KDIGO classification may reduce the prevalence of HIV-infected CKD individuals who are at high risk for a poor prognosis by nearly a half.  相似文献   
94.
Both Langerhans cell histiocytosis (LCH) and nephroblastoma are rare in children. We report herein the first case of a patient with both diseases concurrently. A 2‐year‐old female presented with bone pain and swelling of the right humerus. As a result of the local incision biopsy, she was diagnosed as LCH. A nephroblastoma of the left kidney was discovered during her staging work‐up. After complete resection of the nephroblastoma, she received standard chemoradiotherapy for nephroblastoma. She is alive without relapse 14 months after initial presentation. Pediatr Blood Cancer 2009;52:662–664. © 2009 Wiley‐Liss, Inc.  相似文献   
95.
Midkine (MK) is a growth factor implicated in the development and repair of various tissues, especially neural tissues. MK acts as a reparative neurotrophic factor in damaged peripheral nerves. A postulated role of MK in the degeneration and regeneration of sciatic nerves was explored by comparing wild‐type (Mdk+/+) mice with MK‐deficient (Mdk?/?) mice after freezing injury. In the Mdk?/? mice, a regenerative delay was observed, preceded by a decelerated Wallerian degeneration (WD). The relative wet weight of the soleus muscle slowly declined, and recovery was delayed compared with that in the Mdk+/+ mice. In the regenerating nerve, unmyelinated axons were unevenly distributed, and some axons contained myelin‐like, concentrically lamellated bodies. In the endplates of soleus muscles, nerve terminals containing synaptic vesicles disappeared in both mice. In Mdk?/? mice, the appearance of nerve terminals was delayed in synaptic vesicles of terminal buttons after injury. The recovery of evoked electromyogram was delayed in Mdk?/? mice compared with Mdk+/+ mice. Our results suggested a delay in axonal degeneration and regeneration in Mdk?/? mice compared with Mdk+/+ mice, and the delayed regeneration was associated with a delayed recovery of motor function. These findings show that a lack of MK following peripheral nerve injury is a critical factor in degeneration and regeneration, and manipulation of the supply of MK may offer interesting therapeutic options for the treatment of peripheral nerve damage. © 2009 Wiley‐Liss, Inc.  相似文献   
96.
ObjectiveThis multicenter cross-sectional study aimed to investigate the clinical features and varieties of non-motor fluctuation in Parkinson's disease (PD).MethodsTo identify motor and non-motor fluctuation, we employed the wearing-off questionnaire of 19 symptoms (WOQ-19) in 464 PD patients. We compared the frequency of levodopa-related fluctuation as identified by the WOQ-19 with recognition by neurologists. We compared patients with both motor and non-motor fluctuations with those who only had motor fluctuations. Non-motor fluctuations were separated into psychiatric, autonomic, and sensory categories for further analysis.ResultsThe patients' average age was 70.8 ± 8.4 years (mean ± SD) and disease duration was 6.6 ± 5.0 years. The frequency of motor fluctuations was 69% and for non-motor fluctuation 40%. Fifty-three percent of patients with motor fluctuations also had non-motor fluctuations, whereas 93% of patients with non-motor fluctuations also had motor fluctuations. The WOQ-19 showed a sensitivity of 82% but a specificity of only 40%. The patients with both non-motor and motor fluctuations exhibited more severe motor symptoms, more non-motor symptoms and higher levodopa daily doses (p < 0.05). Patients had significantly higher fluctuation rates if they had psychiatric (49%) and sensory (45%) symptoms than patients with autonomic symptoms (32%, p < 0.01). Forty-eight percent of patients with non-motor fluctuations exhibited more than one type of non-motor fluctuation.ConclusionForty percent of PD patients presented with non-motor fluctuations, and almost half of these exhibited more than one type. Appropriate recognition of levodopa-related fluctuations, both motor and non-motor, can lead to treatment modifications in PD patients.  相似文献   
97.
Okada C 《Clinical calcium》2002,12(4):484-488
Osteoporotic fractures usually occur in elderly patients. If the patients are kept in bed due to pain or therapeutic purposes, they are likely to suffer from various complications such as suppressed physical function, pneumonia, pressure sore, dementia, and deep vein thrombosis. Such disuse syndrome is commonly observed after femoral neck fracture and spinal compression fracture in the osteoporotic patients. In order to prevent the patients from the bed ridden condition, early ambulation is mandatory in consideration of the general condition. After ambulation, the maintenance of daily physical activity and the prevention of additional fractures are essential points in the management of osteoporotic patients.  相似文献   
98.
5A11/Basigin is an immunoglobulin-like glycoprotein expressed on the surface of Müller cells, the apical and basal surfaces of the retinal pigmented epithelium, and photoreceptor cell bodies and their inner segments. Disruption of the 5A11/Basigin gene in the mouse results in photoreceptor degeneration and a corresponding decrease in electroretinogram amplitudes in mature mice. The purpose of this study was to examine the electrophysiology of the 5A11/Basigin null mouse retina at earlier ages than previously examined. Although the architecture of the 5A11/Basigin null mouse retina appears normal, the ERG amplitudes are severely depressed at eye opening, indicating failure in retinal maturation.  相似文献   
99.
Parkinson's disease is the second most common neurodegenerative disorder after Alzheimer's disease. This disease is mainly characterized by tremor, bradykinesia, rigidity and postural instability that results primarily from a loss of dopaminergic neurons of the nigrostriatal pathway. MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is well known to damage the nigrostriatal dopaminergic pathway, as seen in Parkinson's disease. Recent evidence shows that glial-related response plays a key role in the MPTP neurotoxic process, and the blockade of glial activation may be a new therapeutic approach to treating Parkinson's disease. In view of these new insights, this article suggests that the overexpression of S100beta protein secreted by glial cells may be an exacerbating factor in the neurodegeneration of dopaminergic cells in MPTP-treated animals. (c) 2002 Prous Science. All rights reserved.  相似文献   
100.
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