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981.
The etiology and pathogenesis of portal vein thrombosis are unclear. Portal venous thrombosis presentation differs in cirrhotic and tumor-related versus non-cirrhotic and non-tumoral extrahepatic portal venous obstruction (EHPVO). Non-cirrhotic and non-tumoral EHPVO patients are young and present with well tolerated bleeding.Cirrhosis and tumor-related portal vein thrombosis patients are older and have a grim prognosis. Among the 118 patients with portal vein thrombosis, 15.3% had cirrhosis, 42.4% had liver malignancy (primary or metastatic), 6% had pancreatitis (acute or chronic), 5% had hypercoagulable state and 31.3% had idiopathy,12% had hypercoagulable state in the EHPVO group.  相似文献   
982.
983.
Connections of representations of the teeth and tongue in primary somatosensory cortex (area 3b) and adjoining cortex were revealed in owl, squirrel, and marmoset monkeys with injections of fluorescent tracers. Injection sites were identified by microelectrode recordings from neurons responsive to touch on the teeth or tongue. Patterns of cortical label were related to myeloarchitecture in sections cut parallel to the surface of flattened cortex, and to coronal sections of the thalamus processed for cytochrome oxidase (CO). Cortical sections revealed a caudorostral series of myelin dense ovals (O1-O4) in area 3b that represent the periodontal receptors of the contralateral teeth, the contralateral tongue, the ipsilateral teeth, and the ipsilateral tongue. The ventroposterior medial subnucleus, VPM, and the ventroposterior medial parvicellular nucleus for taste, VPMpc, were identified in the thalamic sections. Injections placed in the O1 oval representing teeth labeled neurons in VPM, while injections in O2 representing the tongue labeled neurons in both VPMpc and VPM. These injections also labeled adjacent part of areas 3a and 1, and locations in the lateral sulcus and frontal lobe. Callosally, connections of the ovals were most dense with corresponding ovals. Injections in the area 1 representation of the tongue labeled neurons in VPMpc and VPM, and ipsilateral area 3b ovals, area 3a, opercular cortex, and cortex in the lateral sulcus. Contralaterally, labeled neurons were mostly in area 1. The results implicate portions of areas 3b, 3a, and 1 in the processing of tactile information from the teeth and tongue, and possibly taste information from the tongue.  相似文献   
984.
Imaging features of central nervous system fungal infections   总被引:3,自引:0,他引:3  
Fungal infections of the central nervous system (CNS) are rare in the general population and are invariably secondary to primary focus elsewhere, usually in the lung or intestine. Except for people with longstanding diabetes, they are most frequently encountered in immunocompromised patients such as those with acquired immunodeficiency syndrome or after organ transplantation. Due to the lack of inflammatory response, neuroradiological findings are often nonspecific and are frequently mistaken for tuberculous meningitis, pyogenic abscess or brain tumor. Intracranial fungal infections are being identified more frequently due to the increased incidence of AIDS patients, better radiological investigations, more sensitive microbiological techniques and better critical care of moribund patients. Although almost any fungus may cause encephalitis, cryptococcal meningoencephalitis is most frequently seen, followed by aspergillosis and candidiasis. The biology, epidemiology and imaging features of the common fungal infections of the CNS will be reviewed. The radiographic appearance alone is often not specific, but the combination of the appropriate clinical setting along with computed tomography or magnetic resonance may help to suggest the correct diagnosis.  相似文献   
985.
BACKGROUND: Multi-minicore disease is a rare form of myopathy characterized by slowly progressive or nonprogressive muscle weakness and characteristic multiple cores within the muscle fibers. To the best of our knowledge, this is first documentation of the clinicopathological features of this rare entity from India. MATERIALS AND METHODS: A ll cases of multi-minicore disease diagnosed in our laboratory were retrieved. Clinical and pathological features were reviewed. RESULT: During a period of two years (January 2004 to December 2005), we received 985 muscle biopsies for various reasons. Of which, 15 were diagnosed as myopathies and four of which were of multi-minicore disease. Thus, multi-minicore disease comprises 0.40% of all muscle diseases and 26.6% of all myopathies. All were male and presented in early childhood (first decade of life) with generalized hypotonia and muscle weakness. All of them had dysmorphic facies and three had high arched palate. CPK levels were normal and EMG was myopathic except in one patient. Microscopic examination revealed minimal changes with Type I fibers' predominance but characteristic multiple cores in the myofibers. Ultrastructural examination showed both structured and unstructured cores. CONCLUSIONS: Multi-minicore disease, although a rare form of myopathies, should be suspected in children who present with generalized hypotonia and slowly progressive muscle weakness along with dysmorphic facies.  相似文献   
986.
Background: The occipitocervical contoured rod (CR) stabilization for use in craniovertebral junction (CVJ) pathologies is an effective and economical technique of posterior fusion (PF). Aims: The various indications for CR in CVJ pathologies are discussed. Settings and Design: Retrospective analysis. Materials and Methods: Fifty-four patients (mean age: 31.02 +/- 13.44 years; male: female ratio=5.75:1) who underwent CR stabilization are included. The majority had congenital atlantoaxial dislocation (AAD; n=50); two had CVJ tuberculosis; one each had rheumatoid arthritis and C2-3 listhesis, respectively. The indications for CR fusion in congenital AAD were associated Chiari 1 malformation (C1M) (n=29); occipitalized C1 arch and/or malformed or deficient C1 or C2 posterior elements (n=9); hypermobile AAD (n=2); and, rotatory AAD (n=3). Contoured rod as a revision procedure was also performed in seven patients. Most patients were in poor grade (18 in Grade III [partial dependence for daily needs] and 15 in Grade IV [total dependence]); 15 patients were in Grade II [independent except for minor deficits] and six in Grade I [no weakness except hyperreflexia or neck pain]. Results: Twenty-four patients improved, 18 stabilized and six deteriorated at a mean follow-up (FU) of 17.78 +/- 19.75 (2-84) months. Six patients were lost to FU. In 37 patients with a FU of at least three months, stability and bony union could be assessed. Thirty-one of them achieved a bony fusion/ stable construct. Conclusions: Contoured rod is especially useful for PF in cases of congenital AAD with coexisting CIM, cervical scoliosis, sub-axial instability and/or asymmetrical facet joints. In acquired pathologies with three-column instability, inclusion of joints one level above the affected one by using CR, especially enhances stability.  相似文献   
987.
988.
989.
OBJECTIVE: This study compared the psychometric properties of the Children's Depression Rating Scale-Revised (CDRS-R) and the Montgomery-Asberg Depression Rating Scale (MADRS) in children with major depressive disorder. METHOD: Children (N = 96; ages 8 to 11 years inclusive) with nonpsychotic major depressive disorder were enrolled. Participants were part of a multisite, outpatient, randomized, placebo-controlled, 9-week trial of fluoxetine (10 mg/day for the first week and 20 mg/day thereafter). The CDRS-R and MADRS were completed based on clinician interviews with both parents and children. Classic test theory and item response theory analyses were conducted. RESULTS: The MADRS and CDRS-R total scores were correlated at baseline (r = 0.51) and at study exit (r = 0.85). Cronbach's alpha was .86 (CDRS-R) and .82 (MADRS) at exit. The effect sizes for change from baseline to exit between the fluoxetine and placebo groups were 0.78 (CDRS-R) and 0.61 (MADRS). There was agreement between the CDRS-R and MADRS in the declaration of treatment response (50% improvement from baseline to exit) in 84.2% of children. Test information function favored the CDRS-R. CONCLUSIONS: The CDRS-R showed greater effect size for differentiating drug and placebo and better test information than the MADRS in this study of depressed children.  相似文献   
990.
A simple, specific, accurate and stability-indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of mephenesin and diclofenac diethylamine, using a Spheri-5-RP-18 column and a mobile phase composed of methanol: water (70:30, v/v), pH 3.0 adjusted with o-phosphoric acid. The retention times of mephenesin and diclofenac diethylamine were found to be 3.9 min and 14.5 min, respectively. Linearity was established for mephenesin and diclofenac diethylamine in the range of 50-300 μg/ml and 10-60 μg/ml, respectively. The percentage recoveries of mephenesin and diclofenac diethylamine were found to be in the range of 99.06-100.60% and 98.95-99.98%, respectively. Both the drugs were subjected to acid, alkali and neutral hydrolysis, oxidation, dry heat, photolytic and UV degradation. The degradation studies indicated, mephenesin to be susceptible to neutral hydrolysis, while diclofenac diethylamine showed degradation in acid, H2O2, photolytic and in presence of UV radiation. The degradation products of diclofenac diethylamine in acidic and photolytic conditions were well resolved from the pure drug with significant differences in their retention time values. This method can be successfully employed for simultaneous quantitative analysis of mephenesin and diclofenac diethylamine in bulk drugs and formulations.  相似文献   
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