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101.
Death certificates may lack accuracy and misclassify the cause of death. The validity of proxy-reported cause of death is not well established. The authors examined death records on 336 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study, a national cohort study of 30,239 community-dwelling US adults (2003-2010). Trained experts used study data, medical records, death certificates, and proxy reports to adjudicate causes of death. The authors computed agreement on cause of death from the death certificate, proxy, and adjudication, as well as sensitivity and specificity for certain diseases. Adjudicated cause of death had a higher rate of agreement with proxy reports (73%; Cohen's kappa (κ) statistic = 0.69) than with death certificates (61%; κ = 0.54). The agreement between proxy reports and adjudicators was better than agreement with death certificates for all disease-specific causes of death. Using the adjudicator assessments as the "gold standard," for disease-specific causes of death, proxy reports had similar or higher specificity and higher sensitivity (sensitivity = 50%-89%) than death certificates (sensitivity = 31%-81%). Proxy reports may be more concordant with adjudicated causes of death than with the causes of death listed on death certificates. In many settings, proxy reports may represent a better strategy for determining cause of death than reliance on death certificates.  相似文献   
102.
Craniofacial osteosarcoma is a relatively rare entity comprising about 6.5–7% of all osteosarcomas, whereas it is reported to be one of the most common malignancies of long bones. We present a case of chondroblastic variant of osteosarcoma (COS) of the maxilla in an 18 year-old-girl. She was treated with a subtotal maxillectomy and later referred for adjuvant chemotherapy. The relevant review of literature with regard to clinical, radiographic findings, histopathological similarities to Chondrosarcoma (CS), role of Immunohistochemistry (IHC) and management modalities of Osteosarcoma of jaw bones (OSJ) in comparison with Osteosarcoma of the long bones (OSL) are being presented in this report.  相似文献   
103.
104.
Inflammatory pseudotumor.   总被引:15,自引:0,他引:15  
Inflammatory pseudotumor is a quasineoplastic lesion that most commonly involves the lung and the orbit, but it has been reported to occur in nearly every site in the body. The pathogenesis, natural history, clinical presentation, imaging findings, and treatment options for inflammatory pseudotumor in the lung, heart, gastrointestinal tract, adrenal gland, iliopsoas muscle, orbit, and central nervous system are discussed. Because inflammatory pseudotumors mimic malignant tumors both clinically and radiologically, the radiologist should be familiar with this entity and help avoid unnecessary radical surgery when possible.  相似文献   
105.
106.
A recombinant baculovirus expressing membrane bound form of hemagglutinin–neuraminidase (HN) protein of peste des petits ruminants virus (PPRV) was employed to generate monoclonal antibodies (mAbs) against PPRV-HN protein. Four different mAbs were employed for mapping of regions on HN carrying B-cell epitopes using deletion mutants of PPRV-HN and RPV-H proteins expressed in Escherichia coli as well as PPRV-HN deletion proteins expressed transiently in mammalian cells. The immuno-reactivity pattern indicated that all mAbs bind to two discontinuous regions of amino acid sequence 263–368 and 538–609 and hence the epitopes identified are conformation-dependent. The binding regions for three mAbs were shown to be immunodominant employing competitive ELISA with vaccinated sheep sera. Delineation of functional domains on PPRV-HN was carried out by assessing the ability of these mAbs to inhibit neuramindase activity and hemagglutination activity. Two mAbs inhibited NA activity by more than 63% with substrate N-acetyl neuraminolactose, while with Fetuin one mAb showed inhibition of NA activity (95%). Of the three antigenic sites identified based on competitive inhibition assay, site 2 could be antigenically separated into 2a and 2b based on inhibition properties. All the four mAbs are virus neutralizing and recognized PPRV-HN in immunofluorescence assay.  相似文献   
107.
A multiplex amplification and detection platform for the diagnosis of Mycobacterium bovis and Brucella abortus infection simultaneously in bovine milk and nasal secretions was developed. This system (designated the bovine pathogen detection assay [BPDA]-PCR) consists of duplex amplification of species-specific targets (a region of the BCSP31K gene of B. abortus and a repeat-sequence region in the hsp65 gene of M. bovis, respectively). This is followed by a solid-phase probe capture hybridization of amplicons for detection. On the basis of spiking experiments with normal milk, the analytical sensitivity of the assay was 800 CFU equivalents/ml of milk for B. abortus and as low as 4 CFU equivalents per ml of milk for M. bovis. BPDA-PCR was validated with 45 liver samples from lemmings experimentally infected with B. abortus. The assay sensitivity, based on culture status as a "gold standard," was 93.9%. In this experiment, BPDA-PCR also identified five culture-negative liver samples as positive (41.7%). Field studies for the evaluation of BPDA-PCR were performed with samples from dairy animals from geographically distinct regions (India, Mexico, and Argentina). A high prevalence of shedding of B. abortus (samples from India) and M. bovis (samples from Mexico) was identified by BPDA-PCR. In samples from India, B. abortus shedding was identified in 86% of milk ring test-positive animals (n = 15) and 80% of milk ring test-negative cows (n = 5). In samples from Mexico, M. bovis was identified by PCR in 32.6% of pools (n = 46) of milk that each contained milk from 10 animals and in 56.2% of nasal swabs (n = 121) from cattle from tuberculin test-positive herds. In contrast, the Argentine cattle (n = 70) had a modest prevalence of M. bovis shedding in nasal swabs (2.9%) and milk (1.4%) and of B. abortus in milk (11.4%). On the basis of these analyses, we identify BPDA-PCR as an optimal tool for both screening of herds and testing of individual animals in a disease eradication program. A combination of the duplex assay, screening of milk samples in pools, and the proposed algorithm provides a highly sensitive, cost-effective, and economically viable alternative to serological testing.  相似文献   
108.
A total of 160 White Leghorns of 20 wk age were divided randomly into eight groups. Groups 1, 3, 4 and 5 were fed basal feed and the rest were fed 5% vanaspati supplemented feed until 42 wk of age. From 42 to 54 wk, groups 3, 4 and 5 were fed 1% ferrous sulfate, 100 ppm chlorpyrifos (CPS) and 100 ppm cadmium, respectively, along with basal feed and groups 6, 7 and 8 were fed similar stressors, respectively, along with 5% vanaspati. Groups 1 and 2 served as controls for basal feed and 5% vanaspati feed. Alkaline phosphatase (ALP), alanine transaminase (ALT), total protein, albumin, globulin, A/G ratio, total cholesterol, high density cholesterol (HDL), triglycerides, creatinine, hemagglutination inhibition (HI) titer, and phytohemagglutination (PHA) index were studied. Supplementation of vanaspati resulted in a significant reduction in PHA, cholesterol, albumin and HI titer. Cadmium significantly increased ALP, AST, creatinine and paradoxically increased HDL cholesterol and HI titers. Vanaspati along with cadmium showed similar effects. Administration of CPS lowered PHA index, whereas supplementation along with vanaspati decreased the HI titers and increased the PHA index. Supplementation of vanaspati alone and in combination revealed harmful effects and aggravated the toxicities of CPS and cadmium. Hence, it is concluded that consumption of vanaspati could be harmful.  相似文献   
109.
K Sampathkumar  C Rajasekhar  M J Robson 《Spine》2001,26(10):E213-E215
STUDY DESIGN: A case report of nerve root entrapment due to pigmented villonodular synovitis of lumbar facet joint is reported for which excision was performed. OBJECTIVE: To report a rare cause for nerve root claudication. SUMMARY OF BACKGROUND DATA: Pigmented villonodular synovitis is an uncommon synovial abnormality with an estimated incidence of 1.8 cases per million. Large joints, such as knee and hip, are commonly affected. Involvement of the facet joint is very rare. In our case a high index of suspicion from CT and MRI helped us in the appropriate management. METHODS: A 71-year-old man presented with severe back pain and right-sided L5 sciatica. CT and MRI scans showed a cystic lesion arising from the L5-S1 facet joint. Excision and adequate decompression in the form of undercutting facetectomy were done. RESULTS: The patient had symptomatic improvement with surgery, and at the 3-year follow-up he showed no signs of recurrence. CONCLUSION: Unless pigmented villonodular synovitis is considered in the differential diagnosis of tumors of the vertebral column causing nerve root claudication, it may be overlooked.  相似文献   
110.
A case of closed medial dislocation of the ankle without any associated fracture in a 36 year old man is reported. He was treated by closed reduction under intravenous sedation and plaster application. Two years after injury patient is asymptomatic and had returned to full activities. This case represents a relatively rare and unusual pattern of ankle injury.  相似文献   
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