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991.
We report a case of drug-related toxicity after liver transplantation for hepatocellular carcinoma in a HIV-HCV co-infected patient. Before transplant the patient was on a triple antiretroviral therapy (zidovudine and lamivudine and efavirenz) with a stable CD4+ cell count >500 cells/microL. Liver transplantation was performed with a liver graft showing a 10% of macrosteatosis and with a graft-to-recipient body weight ratio of 1.3. Immunosuppression was achieved with tacrolimus, azathioprine and steroids. The antiretroviral therapy was resumed in the first postoperative day as the early graft function was in the normal range. After a few hours the patient showed myoglobinuria, rhabdomyolysis and a fast-deteriorating graft function. All drugs were withdrawn except steroids and an empiric therapy with riboflavin and glutathione was maintained for five days until myoglobinuria ended. Nevertheless the serum levels of tacrolimus remained in the therapeutic range for six days when it was reintroduced at a reduced dosage (0.01 mg/kg/die). The postoperative course was complicated by tense ascites and severe hyperbilirubinemia without any rejection episodes. The patient was discharged 48 days post-transplantation with a good liver function. During the following year no signs of aggressive HCV-HIV recurrences were observed and the patient is maintaining a CD4+ cells count >400 without antiretroviral therapy.  相似文献   
992.
OBJECTIVE: To assess possible differences in the activity of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, and their inhibitors, the tissue inhibitors of MMPs, TIMP-1 and TIMP-2, in follicular fluid (FF) of women undergoing in vitro fertilization (IVF) treatment and of normally ovulating women. DESIGN: Prospective study. METHODS: MMP-2 and MMP-9 activity was analyzed by gelatin zymography and MMP-2, MMP-9, TIMP-2, TIMP-1 and 17beta-estradiol levels were measured in FF by ELISA. RESULTS: We found significantly reduced MMP levels in FF of women undergoing IVF treatment when compared with those of normally ovulating women. In contrast, the TIMP-1 levels were found significantly increased in FF from IVF patients vs normally ovulating women. No significant differences were found for TIMP-2 between the two groups. CONCLUSIONS: These findings underline a marked difference in MMPs and their inhibitors in the IVF women and the control group. Therefore we assume MMPs depend on hormonal steroidogenesis modulation induced by the gonadotropin protocol for IVF treatment.  相似文献   
993.
Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor involved in such cellular processes as adipogenesis, inflammation, atherosclerosis, cell cycle control, apoptosis, and carcinogenesis. PPAR gamma gene mutations have been found in 4 of 55 sporadic colon cancers, and a chimeric PAX8-PPAR gamma 1 gene frequently generates a chromosomal translocation in thyroid follicular carcinomas, implicating PPAR gamma in tumor suppression. We investigated whether PPAR gamma is involved in the growth regulation of normal and tumor thyroid cells. We found no mutations in PPAR gamma exons 3 and 5 in human thyroid carcinoma cell lines and tissues. Moreover, 1 cell line (NPA) of 6 analyzed did not express PPAR gamma. Treatment of NPA with PPAR gamma agonists did not induce any inhibitory effect. Conversely, PPAR gamma agonists and PPAR gamma overexpression led to a drastic reduction of the cell growth rate in PPAR gamma-expressing thyroid carcinoma cells. Restoration of PPAR gamma expression in NPA cells induced cell growth inhibition; PPAR gamma agonists induced further inhibition. Growth inhibition induced by PPAR gamma agonists or by PPAR gamma gene overexpression in thyroid carcinoma cells was associated with increased p27 protein levels and apoptotic cell death. Should these data be confirmed, PPAR gamma could be a novel target for innovative therapy of thyroid carcinoma, particularly anaplastic carcinomas, which represent one of the most aggressive tumors in mankind and are unresponsive to conventional therapy.  相似文献   
994.
995.
Purpose: Bacterial resistance toward the most used antibiotics is increasing in Helicobacter pylori strains worldwide. Emergence of multidrug resistance significantly affects the efficacy of standard therapy regimens. Therefore, monitoring for primary antimicrobial resistance is essential for H. pylori management in clinical practice.

Methodology: H. pylori isolates obtained from patients consecutively observed in a single center were tested for primary resistance by using E-test method. Bacterial strains showing MIC values?>0.5,?>8 and?>1?mg/L toward clarithromycin, metronidazole and levofloxacin, respectively, were considered resistant. The trend of antibiotic prevalence, either single or combined, during 2010–2016 was assessed.

Results: Antibiotic susceptibility data were available in 1424 (82.3%) out of 1730 tested patients. The overall resistance for all the three antibiotics showed an increasing trend from 2010 to 2013 (clarithromycin: from 19% to 35.6%; metronidazole: from 33.6% to 45.3%; levofloxacin: from 19% to 29.7%; p?<?.001), when a plateau until 2016 was observed (clarithromycin: 35.9%; metronidazole: 40.2%; levofloxacin: 29.3%). A similar trend occurred for clarithromycin-metronidazole combined resistance rate (2010: 11.4%; 2013: 28.2%; 2016: 21.9%).

Conclusion: Our data suggest that prevalence of primary resistance in H. pylori isolates toward the most frequently used antibiotics probably reached a plateau in the last years.  相似文献   
996.
997.
Phylogenetic analysis of influenza viruses collected during December 2009–February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.  相似文献   
998.
999.
1000.

Background

Usefulness of iron chelation therapy in myelodysplastic patients is still under debate but many authors suggest its possible role in improving survival of low-risk myelodysplastic patients. Several reports have described an unexpected effect of iron chelators, such as an improvement in hemoglobin levels, in patients affected by myelodysplastic syndromes. Furthermore, the novel chelator deferasirox induces a similar improvement more rapidly. Nuclear factor-κB is a key regulator of many cellular processes and its impaired activity has been described in different myeloid malignancies including myelodysplastic syndromes.

Design and Methods

We evaluated deferasirox activity on nuclear factor-κB in myelodysplastic syndromes as a possible mechanism involved in hemoglobin improvement during in vivo treatment. Forty peripheral blood samples collected from myelodysplastic syndrome patients were incubated with 50 μM deferasirox for 18h.

Results

Nuclear factor-κB activity dramatically decreased in samples showing high basal activity as well as in cell lines, whereas no similar behavior was observed with other iron chelators despite a similar reduction in reactive oxygen species levels. Additionally, ferric hydroxyquinoline incubation did not decrease deferasirox activity in K562 cells suggesting the mechanism of action of the drug is independent from cell iron deprivation by chelation. Finally, incubation with both etoposide and deferasirox induced an increase in K562 apoptotic rate.

Conclusions

Nuclear factor-κB inhibition by deferasirox is not seen from other chelators and is iron and reactive oxygen species scavenging independent. This could explain the hemoglobin improvement after in vivo treatment, such that our hypothesis needs to be validated in further prospective studies.  相似文献   
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