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31.
Witold Kycler Bronisława Szarzyńska Cezary Łoziński Konstanty Korski Katarzyna Lamperska 《Reports of Practical Oncology and Radiotherapy》2012,17(1):13-18
Background/aimThe aim of our study was to check how MGMT methylation status together with known factors influenced the risk of colon cancer development.Materials and methodsWe examined patients with colon polyps. Information concerning gender, age, lifestyle, diet, anthropometry and medical information, including cancer and family history of cancer, was analyzed. Polymorphism variety of MGMT gene was investigated in another study. Genetic analysis for MGMT methylation assessment was performed for polyp tissue samples from 143 patients.ResultsPositive methylation MGMT status was found in 55 patients. There was no correlation between gender and MGMT methylation status (p = 0.43). We did not find correlation between patients younger and older than 60 (p = 0.87). There was no correlation between smoking and MGMT methylation status (p = 0.36). We did not find correlation between BMI and MGMT methylation status (p = 0.86). We did not find correlation between MGMT methylation status and colon cancer in familial history (p = 0.45).ConclusionOur study showed no correlations between methylation status of MGMT polymorphisms and clinical features like age, gender, polyp localization, smoking status, or obesity. It has been shown previously that MGMT methylation status may show nonspecific methylation in colon polyps. Gene methylation status in adenoma tissues has also been associated by other authors with the adenoma's size, histology, and degree of atypia. In our study, we evaluated the gene methylation status in colon polyps and found no association with adenoma characteristics. The present study showed no correlation for MGMT methylation in polyps in different regions of colon. 相似文献
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Łukasz Jaremko Mariusz Jaremko Paweł Pasikowski Marek Cebrat Piotr Stefanowicz Marek Lisowski Jolanta Artym Michał Zimecki Igor Zhukov Zbigniew Szewczuk 《Biopolymers》2009,91(6):423-431
Recently, ubiquitin was suggested as a promising anti‐inflammatory protein therapeutic. We found that a peptide fragment corresponding to the ubiquitin50–59 sequence (LEDGRTLSDY) possessed the immunosuppressive activity comparable with that of ubiquitin. CD and NMR spectroscopies were used to determine the conformational preferences of LEDGRTLSDY in solution. The peptide mixture, obtained by pepsin digestion of ubiquitin, was even more potent than the intact protein. Although the peptide exhibited a well‐defined conformation in methanol, its structure was distinct from the corresponding 50–59 fragment in the native ubiquitin molecule. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 423–431, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com 相似文献
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M. Parczewski M. Leszczyszyn-Pynka M. Kaczmarczyk G. Adler A. Bińczak-Kuleta B. Łoniewska A. Boroń-Kaczmarska A. Ciechanowicz 《Journal of applied genetics》2009,50(2):159-166
Genetic susceptibility to HIV infection was previously proven to be influenced by some chemokine receptor polymorphisms clustering
on chromosome 3p21. Here the influence of 5 genetic variants was studied: Δ32CCR5, G(-2459)ACCR5, G190ACCR2, G744ACX3CR1 and C838TCX3CR1. They were screened in a cohort of 168 HIV-1 positive adults [HIV(+) group] and 151 newborns [control group] from northwestern
Poland. PCR-RFLP was performed to screen for the variants (except for A32CCR5 polymorphism, where PCR fragment size was sufficient to identify the alleles) and then electrophoresed on agarose gel to
determine fragment size. Distribution of genotypes and alleles was not significantly different between the groups except for
theCCR5 polymorphisms, with the A32 allele and the (-2459)ACCR5 allele more frequent among neonates than in the HIV(+) group. No Δ32/Δ32 homozygotes were found in the HIV(+) group, but
16.1% were Δ32/wt heterozygotes. In the control group, 1.3% were Δ32/Δ32 homozygotes and 26.0% were Δ32/wt heterozygotes.
Linkage between the chemokine polymorphisms was calculated using the most informative loci for haplotype reconstruction. Haplotypes
containing Δ32 CCR5,190GCCR2 and 744ACX3CR1 were found to be significantly more common in the control group. This suggests an association between these haplotypes and
resistance to HIV-1 infection. 相似文献
35.
Dorota Łażewska Kamil Kuder Xavier Ligneau Jean-Claude Camelin Walter Schunack Holger Stark Katarzyna Kieć-Kononowicz 《Bioorganic & medicinal chemistry》2009,17(8):3037-3042
Synthesis and biological activities of a series of homo- or substituted piperidine unsymmetrical diethers are described. The novel compounds were evaluated for histamine H3 receptor binding affinities at recombinant human H3 receptor stably expressed in HEK-293 cells. All diethers showed in vitro affinities in nanomolar concentration range. The most potent compounds are 1-[3-(3-(4-chlorophenoxy)propoxy)propyl]-3-methylpiperidine 11 (Ki = 3.2 nM) and 1-[3-(3-(4-chlorophenoxy)propoxy)propyl]azepane 13 (Ki = 3.5 nM). 相似文献
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