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11.
12.
Although the haemagglutination inhibition assay is considered the "gold standard" for antigenic characterisation of influenza viruses, some limitations of this technique are well known. A new microneutralisation assay, as a tool for antigenic characterisation of influenza B viruses, has been standardised and its performance evaluated in comparison with the haemagglutination inhibition test in the light of molecular characterisation of the haemagglutinin. Twelve B viruses belonging to the two lineages and the four sub-lineages discriminated by phylogenetic analysis of HA were tested. The microneutralisation assay clearly distinguishes viruses belonging to different lineages and, in addition, discriminates strains belonging to different sub-lineages that are poorly or not discriminated using the haemagglutination inhibition test. This new microneutralisation assay could provide a useful tool for antigenic characterisation of circulating influenza viruses and contribute, together with the haemagglutination inhibition test and sequence analysis of the haemagglutinin and neuraminidase, in the choice of the strain for use in vaccine composition.  相似文献   
13.
Chromosome investigations were carried out in 7 patients with Fanconi's anemia, type Estren-Dameshek. The frequency and types of chromosome instability found in cultured lymphocytes were in accord with those detected in individuals with classical Fanconi's anemia. The break-point distribution indicates a significant excess of breaks in chromosomes No. 1, 2, and 7 and a deficit in No. 18 and X and Y chromosomes. There was a clear clustering of breaks at certain locations in chromosomes No. 1, 2, 3, 7, 9, and 14. The location of the breaks with respect to the bands demonstrated an almost exclusive involvement of the lighter bands, regardless of the banding method used. These results suggest that most breaks take place in the interbands between the G and R bands. In all patients, chromosome instability was less frequent in direct bone marrow preparations than in lymphocyte cultures. However, cultured bone marrow cells showed a significant increase of chromosome aberrations. On the whole, the chromosome data derived from this series of patients are in agreement with those obtained in individuals with classical Fanconi's anemia and give no support to the idea of cytogenetic heterogeneity between subjects affected by these two forms of childhood aplastic anemia.  相似文献   
14.
A fast and simple extraction procedure was developed for simultaneous determination in bovine liver of two veterinary drugs, widely used as growth promoters in meat production: dexamethasone (a synthetic corticosteroid drug) and clenbuterol (a beta2‐adrenergic agonist drug). Liver samples were extracted by acetonitrile, without any clean‐up step. Two different ELISAs, specific for the two classes of drugs, were used to determine the residue concentration in the extracts. The intra‐ and inter‐extraction variability was determined at different concentrations: the intra‐extraction coefficients of variation (CVs) were between 2.5 and 17.7% for dexamethasone and between 0.9 and 9.8% for clenbuterol; the inter‐extraction CVs were between 2.0 and 16.8% for dexamethasone and between 0.5 and 10.8% for clenbuterol. Recovery ranged from 92 to 154% for dexamethasone and from 78 to 105% for clenbuterol. The limit of detection was 1.43 ng g?1 and 0.43 ng g?1, respectively. The limit of quantification for dexamethasone was 2.09 ng g?1 and for clenbuterol was 0.72 ng g?1. The combination of the new extraction procedure with an ELISA detection permitted the rapid semi‐quantitative determination of both dexamethasone at its maximum residue level (MRL: 2.5 ng g?1 in liver tissue), and clenbuterol at low concentration level.  相似文献   
15.
The cirrhotic condition is characterized by a series of changes in physiological functions and of subclinical alterations that imply an abnormal and fragile adaptive pattern with reduced resistance to superimposed distress. In the care of the critically ill cirrhotic patient, the supportive measures aimed at maintaining physiological stability through the control of such debilitating factors have a key role and are not secondary in importance to the more obvious measures needed to treat clinically evident and specific alterations or complications. The relationship between hepatic malfunction and the development of these physiological abnormalities is not fully understood. Our knowledge of the problem, however, has been recently improved and the need for supportive measures motivated by a series of notions on cardiorespiratory and metabolic abnormalities and interactions in hepatic decompensation.
Resumen La condición cirrótica se caracteriza por una serie de cambios en las funciones fisiológicas y por alteraciones subclinicas que implican un patrón de adaptación anormal y fragil de resistencia reducida al estrés. Estas incluyen disfunción respiratoria con tendencia a la hipoxemia arterial en presencia de elevados indices cardiacos, una situatión crónica de hiperdinamismo cardiovascular pero con precaria eficacia miocárdica y latente riesgo de falla de alto débito, y cambios metabólicos que se traducen en un estado de fallas multisistémicas interrelacionadas características del cirrótico. En el cuidado del paciente cirrótico en estado crítico, las medidas de soporte orientadas al mantenimiento de la estabilidad fisiológica mediante el control de tales factores debilitantes tienen una importancia capital y no son secundarias frente a aquellas muy obvias que se requieren para tratar alteraciones o complicaciones específicas y clínicamente evidentes. La relación entre la disfunción hepática y el desarrollo de las mencionadas anormalidades fisiológicas no está totalmente aclarada, sin embargo, el estado de nuestro conocimiento sobre el problema ha sido enriquecido recientemente y se ha fortalecido la necesidad de establecer medidas de soporte por una serie de nociones relativas a las anormalidades e interacciones cardiorrespiratorias y metabólicas de la descompensación hepática.

Résumé La cirrhose est caractérisée par des séries de variations des fonctions physiologiques et de modifications cliniques qui impliquent des modalités d'adaptation anormale et fragile se traduisant par une résistance réduite à l'état de détresse ou peut se trouver le cirrhotique. Des mesures appropriées pour maintenir la stabilité physiologique ont un rôle principal en présence de ces facteurs défavorables. Elles ne doivent pas être considérées comme moins importantes que les mesures essentielles qui sont nécessaires pour traiter les complications et les modifications cliniques spécifiques. La relation entre l'altération des fonctions du foie et le développement des anomalies physiologiques précitées n'est pas parfaitement élucidée, cependant, nos connaissances de ce problème ont été récemment améliorées et le besoin de mesures adéquates de soutien est devenu manifeste en raison de séries acquises de notions concernant les anomalies cardio-respiratoires et métaboliques ainsi que les interactions de la décompensation hépatique.
  相似文献   
16.
The removal of oil from water is a worldwide challenge that must be faced to avoid irreversible marine habitat destruction. A novel fast and simple technique to obtain polydimethylsiloxane (PDMS) membranes is developed using the photopolymerization technique. The high reactivity of the acrylated PDMS formulation toward photo-induced free radical polymerization is assessed via the differential scanning photo-calorimetry (photo-DSC) technique. Two different membranes dense or porous are developed and investigated. Porous membranes, having 100–200 µm as pore size, are obtained using a low-cost environmentally friendly sodium chloride template. Thanks to the hydrophobic/oleophilic intrinsic characteristic of PDMS, the UV-cured membranes can selectively remove dodecane, selected as the target oil, from water. The dodecane sorption capability of both membranes is investigated and compared. Moreover, the membranes can be easily reused since the adsorbed oil can be recovered by simply compressing the membrane. Those PDMS sorbents show high mechanical stability after five adsorption/desorption cycles.  相似文献   
17.
· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
18.
PURPOSE: Stroma cells play a relevant role in tumor development and progression. We investigated the activity of herceptin (HER), a humanized monoclonal antibody widely used for the treatment of HER2-overexpressing epithelial cancer, toward stroma cell lines L87/4 and L88/5. EXPERIMENTAL DESIGN: We studied the antiproliferative potential of HER and role of human serum in HER activity. We also investigated the ability of HER to alter ancillary functions of L87/4 and L88/5, such as support to long-term hematopoiesis, growth factor production, breast cancer cell adhesion, and proliferation. RESULTS: Flow cytometry showed that HER2 membrane expression in L87/4 and L88/5 stroma cells was intermediate between the expression in HER2-negative/dim MCF-7 breast cancer cells and HER2-bright SK-BC3 breast cancer cells. HER2 gene amplification was not detected by fluorescence in situ hybridization in either stromal cell lines. HER significantly inhibited L87/4 and L88/5 proliferation. Mean ID(50)s were found to be 2000 and 1700 micro g/ml for L87/4 and L88/5, respectively, after 3-day exposure and 800 micro g/ml for both cell lines after 9-day exposure. The presence of 10% human serum in the culture increased HER inhibitory activity. IC(50) of stroma cells was found to be intermediate between HER2-bright breast cancer cells (SK-BC3) and HER2-negative/dim breast cancer cells (MCF-7). The drug did not significantly affect the ability of stroma cells to support long-term hematopoiesis in the cobblestone area forming cell assay. In contrast, in coculture assay, MCF7 cells demonstrated a worse adhesion and growth capability on HER-treated stroma layers when compared with untreated stroma. Moreover, HER significantly reduced vascular endothelial growth factor production by L88/5 cells. CONCLUSIONS: Our data support the novel finding that HER may have a relevant activity against stroma cells.  相似文献   
19.
Long-term central venous catheters (CVCs) have considerably improved the management of cancer patients because they facilitate chemotherapy, transfusions, parenteral nutrition, and blood sampling. However, the use of long-term CVCs, especially for chemotherapy, has been associated with the occurrence of upper-limb deep venous thrombosis (UL-DVT). The incidence of clinically overt UL-DVT related to CVCs has been reported to vary between 0.3% and 28.3%. The incidence of CVC-related UL-DVT screened by venography reportedly varies between 27% and 66%. The incidence of clinically overt pulmonary embolism (PE) in patients with CVC-related UL-DVT ranges from 15% to 25%, but an autopsy-proven PE rate of up to 50% has been reported. Vessel injury caused by the procedure of CVC insertion, venous stasis caused by the indwelling CVC, and cancer-related hypercoagulability are the main pathogenetic factors for CVC-related venous thromboembolism (VTE). Several studies have assessed the benefit of the prophylaxis of UL-DVT after CVC insertion in cancer patients. According to the results of these studies, prophylaxis with low molecular weight heparin or a low fixed dose of warfarin has been recently proposed. However, the limitations of the experimental design of the prophylactic studies do not allow definitive recommendations. The recommended therapy for UL-DVT associated with CVC is based on anticoagulant therapy with or without catheter removal. This review focuses on the epidemiology, pathogenesis, diagnosis, prevention, and treatment of VTE in cancer patients with long-term CVC.  相似文献   
20.
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.  相似文献   
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