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1.
Because IL-6 has been involved in the pathogenesis of acute monoblastic leukemia, we investigated thein vitro anti-proliferative effect and thein vivo anti-tumoral effect of an anti-IL-6 murine monoclonal antibody (mAb) in a patient with MSB type acute leukemia. In the current study, we clearly show the IL-6 dependence of monoblastic cell viability and proliferationin vitro in short-term cultures of malignant cells and the clinical activity of the anti-IL-6 murine mAb. The complete neutralization of IL-6in vivo was associated with a transient but complete disappearance of malignant monoblastic cells in the peripheral blood, with improvement or even normalization of several other biological parameters of disease activity, No immunization against the anti-IL-6 murine mAb was observed.  相似文献   
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Central diabetes insipidus (DI) is extremely rare during the neonatal period. Most cases of central DI are secondary to a known aetiology. Substitutive treatment with desmopressin is effective with nasal or oral preparation, but doses are variable and must be tailored individually. We report on a case in a very low birth weight infant with an idiopathic central DI during the first month of life. He was successfully treated with oral desmopressin. The treatment was maintained after discharge with low doses desmospressin.  相似文献   
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Nosocomial infections are a preoccupation in a pediatric hospital mainly during the winter with bronchiolitis and gastroenteritis epidemics. We have examined the risk factors of nosocomial infections. MATERIAL AND METHODS: A prospective study was conducted between November, 1999 and March, 2000 in the infants units of the Le Havre hospital. We systematically listed the admissions and contacted the family after their discharge by phone. A geographic information system was implemented to display the epidemiological data; this software is able to illustrate the sectors at risk. RESULTS: During the study, 687 infants were hospitalized of whom 458 for bronchiolitis and community-acquired gastroenteritis. Mean age was 5.4 months old. No nosocomial bronchiolitis occurred. Prevalence of nosocomial gastroenteritis was 10% (68 cases including nine after discharge). Infants with nosocomial infection were younger than those with community-acquired infection (6.6 months vs. 11.2 months, P < 0.01). The mean length of stay was longer in nosocomial infection (7.7 vs. 4.1 days, P < 0.05). Among the infants with bronchiolitis, 16% have developed nosocomial intestinal infections (RR = 2.65, IC: 1.59-4.4; P < 0.01). The geographic analysis pointed the area with nosocomial risk (bedroom without water, nearness of nurse office and games room). CONCLUSION: Geographic information system is a part of the quality control system and may have some interaction effect on final decision making. Incidence of nosocomial infections showed the need for a prevention strategy in a pediatric hospital.  相似文献   
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AIDS Subacute Encephalitis: Identification of HIV-Infected Cells   总被引:21,自引:6,他引:21       下载免费PDF全文
Human immunodeficiency virus (HIV) RNA and proteins were detected in the brains of several AIDS patients with subacute encephalitis, by in situ hybridization and immunohistology. The majority of infected cells were mononucleated and bore processes. Using single and double immunohistologic procedures, the authors identified these cells as macrophages. The majority of them had the phenotype of microglial cells (Leu-M3-, CD4-), others were labeled with markers of circulating macrophages (Leu-M3+, CD4+/-). The presence of HIV RNA and proteins in CD4- cells could be explained by depressed CD4 antigen expression, as a result of infection or macrophage tissue differentiation.  相似文献   
6.
Extracellular superoxide dismutase (EC-SOD) controls the availability of extracellular superoxide (O 2 - ), which is important for a variety of physiological pathways, including the primary means of inactivating nitric oxide (NO). The role of EC-SOD in neurobehavioral function has been until now unexplored. In the current studies, the phenotypic expression of genotypic alterations of EC-SOD production in mice were characterized for spatial learning and memory. Dramatic impairments in spatial learning in the win-shift 8-arm radial maze were seen in both EC-SOD knockout mice and EC-SOD overexpressing mice. The EC-SOD overexpressing mice were further characterized as having significant deficits in a repeated acquisition task in the radial-arm maze, which permitted the dissociation of long and short-term learning. Long-term learning was significantly impaired by EC-SOD overexpression, whereas short-term learning was not significantly affected by EC-SOD overexpression. NO systems have been shown to be importantly involved in learning and memory. This may be important in the current studies because EC-SOD has primary control over the inactivation of NO. We found that EC-SOD overexpressing mice were resistant to the cognitive effects of L-NAME (NG-nitro-L-arginine methyl ester hydrochloride), an NO synthase inhibitor. Decreased NO catabolism in these mice may have served to counter the effects of NOS inhibition by L-NAME. The current finding that EC-SOD levels that were either higher or lower than controls impaired learning demonstrates that the proper control of brain extracellular (O 2 - ) may be more vital than merely reduction of brain extracelluar (O 2 - ) in maintaining adequate learning function.  相似文献   
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Calcium plays a fundamental role in many essential for life functions. Ionized calcium (Ca(++) ) represents free fraction and 50% of the total calcium in the plasma is accepted as its physiologically active form. On almost all laboratories, only total calcium is routinely measured, and ionized calcium concentration is calculated based on calcium, protein or albumin concentrations for many plasma sample or with others parameters like pH. Since 1935, the literature was abounted with "correction" formulae of varying degree of sophistication. Many laboratories routinely use correction formulae to either calculate an "adjusted" or "corrected" total calcium, or "ionized" fraction is calculated,but these determinations lack of accuracy or precision. Errors associated with the measurement of the other variables contribuate to the difficulty in producing a useful correction formulae. Direct measurement of ionized calcium by potentiometry is the method of choice for this assay. Improvements in ion selective electrodes (ISE) technology make possible the routine clinical measurement of Ca(++). However this technology implies several obligations for its use, particulary in blood ampling, storage and transport. In this review, characteristics of different available analysers are described. We think that Ca(++) should be systematically performed and not calculated in pathological situations where an possible alteration of the calcium metabolism is found especially in multiple myeloma in which paraprotein may bind calcium.  相似文献   
10.
A basic issue in neurosciences is to look for possible relationships between brain architecture and cognitive models. The lack of architectural information in magnetic resonance images, however, has led the neuroimaging community to develop brain mapping strategies based on various coordinate systems without accurate architectural content. Therefore, the relationships between architectural and functional brain organizations are difficult to study when analyzing neuroimaging experiments. This paper advocates that the design of new brain image analysis methods inspired by the structural strategies often used in computer vision may provide better ways to address these relationships. The key point underlying this new framework is the conversion of the raw images into structural representations before analysis. These representations are made up of data-driven elementary features like activated clusters, cortical folds or fiber bundles. Two classes of methods are introduced. Inference of structural models via matching across a set of individuals is described first. This inference problem is illustrated by the group analysis of functional statistical parametric maps (SPMs). Then, the matching of new individual data with a priori known structural models is described, using the recognition of the cortical sulci as a prototypical example.  相似文献   
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