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61.
Surveillance System. A network of 32 Spanish hospitals, serving approximately 9.6 million persons, submitted antimicrobial-susceptibility data on 7,098 invasive Escherichia coli species (2001-2003). Resistance to ampicillin, cotrimoxazole, ciprofloxacin, gentamicin, and tobramycin was found at rates of 59.9%, 32.6%, 19.3%, 6.8%, and 5.3%, respectively. Resistance to multiple drugs increased from 13.8% in 2001 to 20.6% in 2003 (p <0.0001). Antimicrobial consumption data were obtained from the Spanish National Health System. In spite of decreased cephalosporin and beta-lactam use, overall extended-spectrum beta-lactamase production increased from 1.6% (2001) to 4.1% (2003) (p <0.0001), mainly due to the rising prevalence of cefotaximases. Resistance to ciprofloxacin significantly increased, mostly in community-onset infections, which coincided with a rise in community quinolone use. Cotrimoxazole resistance remained stable at approximately 30%, even though its use was dramatically reduced.  相似文献   
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OBJECTIVE: The present work evaluated the effects of conjugated linoleic acid (CLA) on various aspects of triacylglycerol metabolism in skeletal muscle to determine the potential involvement of this tissue in the effect of CLA to decrease body fat. METHODS: Animals were randomized to three groups that were fed atherogenic diets that provided different amounts of trans-10,cis-12 CLA (0%, 0.5%, or 1%) for 6 wk. Muscle triacylglycerol, protein, water, glycogen, and DNA contents and fatty acid profile in triacylglycerols were analyzed. Lipoprotein lipase and carnitine palmitoyltransferase-I (CPT-I) activities were assessed. Triacylglycerol, glucose, and insulin concentrations were evaluated in serum. RESULTS: The high dose of CLA increased food efficiency and gastrocnemius muscle weight. CLA feeding resulted in decreased muscle triacylglycerol content without changes in protein, water, glycogen, and DNA contents or in cell size (protein/DNA ratio) and produced decreased lipoprotein lipase activity and increased CPT-I activity. No differences were found between CLA doses. CLA feeding led to the saturation of stored triacylglycerols. CONCLUSIONS: Decreased fatty acid uptake and increased fatty acid oxidation can contribute to the decreased muscle triacylglycerol content observed in hamsters fed the CLA diets. The increase in muscle fatty acid beta-oxidation might ultimately prevent storage of triacylglycerols in adipose tissue. Nevertheless, the lack of matching of lipoprotein lipase and CPT-I modifications makes it difficult to ensure that skeletal muscle is responsible, at least in part, for the effect of CLA on decreasing body fat; thus, further research is needed.  相似文献   
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In non-small cell lung cancer, EGFR gene mutations identify a patient sub-population with different clinical characteristics and treatment responses than those who do not present these mutations. There are mutations that lead to increased sensitivity to EGFR-targeted therapy, as well as mutations that result in resistance. The determination of EGFR mutations involves a change in the therapeutic approach to lung cancer patients in current clinical practice. In this article we present a case of a patient suffering from a metastatic lung adenocarcinoma with an activating mutation on diagnosis, initially responding to treatment with erlotinib, who subsequently developed a secondary resistance due to acquiring the T790M mutation in exon 20 of the EGFR gene.  相似文献   
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A pilot study has been designed in order to determine the tolerance and effectiveness of recombinant interferon gamma (rIFN-gamma) in chronic hepatitis B virus (HBV) infection. Eight HBsAg, HBeAg, HBV-DNAp and HBV-DNA-positive patients were randomly assigned to one of two groups. In group 1, 0.25 mg of rIFN-gamma/m2 body surface was administered daily for 28 days to 4 patients. In group 2, 0.10 mg of rIFN-gamma was administered to 4 patients under the same conditions. All the patients concluded the treatment and were observed over 11 more months. During treatment, 6 out of 8 patients showed decreased levels of HBV-DNA and HBV-DNAp. In addition, by the 8th month of follow-up, six patients became negative for HBV-DNAp and 2 for HBcAg; all patients remained positive for HBV-DNA. At the end of the study, only 2 patients remained negative for HBV-DNAp, 4 for HBcAg and one became negative for HBV-DNA. No differences in antiviral effect were observed between the two groups. Furthermore, the T4/T8 lymphocytes ratio increased during therapy. In conclusion, rIFN-gamma may play a role in the treatment of chronic HBV infection.  相似文献   
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Sucrose synthase (SUS) catalyzes the reversible conversion of sucrose and a nucleoside diphosphate into the corresponding nucleoside diphosphate-glucose and fructose. In Arabidopsis, a multigene family encodes six SUS (SUS1-6) isoforms. The involvement of SUS in the synthesis of UDP-glucose and ADP-glucose linked to Arabidopsis cellulose and starch biosynthesis, respectively, has been questioned by Barratt et al. [(2009) Proc Natl Acad Sci USA 106:13124-13129], who showed that (i) SUS activity in wild type (WT) leaves is too low to account for normal rate of starch accumulation in Arabidopsis, and (ii) different organs of the sus1/sus2/sus3/sus4 SUS mutant impaired in SUS activity accumulate WT levels of ADP-glucose, UDP-glucose, cellulose and starch. However, these authors assayed SUS activity under unfavorable pH conditions for the reaction. By using favorable pH conditions for assaying SUS activity, in this work we show that SUS activity in the cleavage direction is sufficient to support normal rate of starch accumulation in WT leaves. We also demonstrate that sus1/sus2/sus3/sus4 leaves display WT SUS5 and SUS6 expression levels, whereas leaves of the sus5/sus6 mutant display WT SUS1-4 expression levels. Furthermore, we show that SUS activity in leaves and stems of the sus1/sus2/sus3/sus4 and sus5/sus6 plants is ~85% of that of WT leaves, which can support normal cellulose and starch biosynthesis. The overall data disprove Barratt et al. (2009) claims, and are consistent with the possible involvement of SUS in cellulose and starch biosynthesis in Arabidopsis.  相似文献   
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Background  

Patients with high-grade glioma can be treated with carmustine wafers or following the Stupp protocol. As far as we are aware, no scientific evidence has been published comparing the two treatments. The primary objective of this study was to analyse the survival of groups of patients with each of these treatment modalities. The secondary objective was to assess the influence of the usual prognostic factors on the patients in our hospital.  相似文献   
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