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291.
The pear (Pyrus communis L.) is a fruit species grown in many temperate regions of the world. Turkey harbours a rich and ancient pear germplasm adapted to diverse ecological regions of the country. The aim of this study was to genetically characterise locally grown Anatolian pear germplasm. We have analysed large numbers (228) of pear accessions originated from six eco‐geographically diverse regions using 18 simple sequence repeat (SSR) markers and identified 308 SSR alleles. Genetic similarities among the accessions examined were generally below 80%. The highest heterozygosity rate was obtained for the SSR locus ‘CH02D11’ derived from apples and ‘KA16’ and ‘NH0021a’ derived from pears. No identical or synonymous genotypes were found, while five homonymous genotypes were identified. Factorial correspondence analysis could not clearly separate different pear accession groups studied, suggesting that Anatolian pear accessions were intermixed possibly due to gene flow and/or germplasm movements between different eco‐geographical regions. However, most pear accessions were grouped according to their collection sites in structure analyses. The SSR data reported here for Anatolian pear accessions will be valuable for future germplasm management efforts as well as for comparative studies that investigate genetic relationships of pears from Anatolia and the surrounding regions.  相似文献   
292.
The origin of the turtle plastron is not well understood, andthese nine bones have been homologized to the exoskeletal componentsof the clavicles, the interclavicular bone, and gastralia. Earlierdata from our laboratory showed that the plastral bone-formingcells stained positively for HNK-1 and PDGFR, two markers ofskeletogenic neural crest cells. We have now shown that theHNK-1+ cells are also positive for p75 and FoxD3, affirmingtheir neural crest identity. These cells originate from thedorsal neural tube of stage-17 turtle embryos, several daysafter the original wave of neural crest cells have migratedand differentiated. Moreover, we have demonstrated the existenceof a staging area, above the neural tube and vertebrae, wherethese late-emigrating neural crest cells collect. After residingin the carapacial staging area, these cells migrate to formthe plastral bones. We also demonstrate that one bone of thecarapace, the nuchal bone, also stains with HNK-1 and with antibodiesto PDGFR. The nuchal bone shares several other properties withthe plastral bones, suggesting that it, too, is derived fromneural crest cells. Alligator gastralia stain for HNK-1, whiletheir ribs do not, thus suggesting that the gastralial precursormay also be derived from neural crest cells.  相似文献   
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Selenium, an essential biological trace element present in both prokaryotic and eukaryotic cells, exerts its regulatory effect in a variety of cellular events, including cell growth, survival, and death. Selenium compunds have been shown in different cell lines to inhibit apoptosis by several mechanisms. Serine/threonine phosphatases (STPs) are potentially important in selenite-induced apoptosis because of their role in regulation of diverse set of cellular processes. In this study, the regulatory role of STPs in selenite-induced apoptosis has been implied by the use of two specific inhibitors: ocadaic acid and calyculin A. Our results show a decrease in cell density in HepG2 cells under selenite treatment. Resulting specific enzyme activities showed a concentration-dependent increase in all three phosphatase activities after 24 h in cells treated with 5 μM selenite and these activities decreased at 48 and 72 h. However, in cells treated with 10μM selenite, PP2A and PP2B decreased at 48 h, whereas PP2C activity did not change at this dose. In cells treated with 25μM, there was not a significant change in PP2C activity. These data suggest that the most specific response to selenite treatment was in PP2A and PP2B activities in a dose-dependent manner. Our results with OA and Cal-A further support the view that PP1 and PP2A might act as negative regulators of growth. With these data, we have first demonstrated the role of serine/threonine protein phosphatases in the signaling pathway of selenite-induced apoptosis and resulting cytotoxicity  相似文献   
295.
The aim of this study was to investigate the possible association of serotonin 2A receptor gene (HTR2A) -1438 G/A polymorphism and CYP1A2 gene 163C/A polymorphism with tardive dyskinesia (TD) in a Turkish population. A total of 47 patients with persistent TD, 80 patients who were consistently without TD, and 100 healthy controls were included in this study. The polymorphic regions of -1438 G/A polymorphism of HTR2A receptor gene (rs6311) and 163C/A of CYP1A2 (rs762551) gene were amplified using polymerase chain reaction (PCR), followed by digestion with restriction enzymes MspI and Bsp1201. Genotype and allele frequencies were calculated by the chi(2)-test. Crude and adjusted odds ratios (ORs) were estimated, and 95% confidence intervals (CIs) were computed by multivariate logistic regression analysis. The genotype and allele frequencies of HTR2A and CYP1A2 gene were similar in schizophrenia with TD, schizophrenia without TD, and healthy controls. The logistic regression analysis showed that cumulative exposure to antipsychotic drugs for every year (p = 0.003; OR = 1.15; CI = 1.07-1.23), and AA genotype of HTR2A gene (p = 0.0258; OR = 4.34; CI = 1.19-15.81) are risk factors for TD. The same logistic regression model showed no association between CYP1A2 polymorphism and TD. The results of the present study seem to indicate that HTR2A gene polymorphism influences the tendency to express TD following prolonged antipsychotic drug exposure in Turkish schizophrenia patients.  相似文献   
296.
Molecular Biology Reports - Congenital adrenal hyperplasia (CAH) is an autosomal recessive genetic disorder due to presence of mutations in the genes involved in the metabolism of steroid hormones...  相似文献   
297.
Göksel  Ş.  Akçelik  N.  Özdemir  C.  Akçelik  M. 《Microbiology》2022,91(3):278-285
Microbiology - The anti-biofilm effects of the following probiotic LAB strains: Lactobacillus plantarum M16 (producer of plantarisin), Lactobacillus sake M17 (producer of sakacin), Pediococcus...  相似文献   
298.
International Microbiology - Gallbladder and biliary tract infections are diseases with high mortality rates if they are not treated properly. Microbiological evaluation of perioperatively...  相似文献   
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300.
RON belongs to the c-MET family of receptor tyrosine kinases. As its well-known family member MET, RON and its ligand macrophage-stimulating protein have been implicated in the progression and metastasis of tumors and have been shown to be overexpressed in cancer. We generated and tested a large number of human monoclonal antibodies (mAbs) against human RON. Our screening yielded three high-affinity antibodies that efficiently block ligand-dependent intracellular AKT and MAPK signaling. This effect correlates with the strong reduction of ligand-activated migration of T47D breast cancer cell line. By cross-competition experiments, we showed that the antagonistic antibodies fall into three distinct epitope regions of the RON extracellular Sema domain. Notably, no inhibition of tumor growth was observed in different epithelial tumor xenografts in nude mice with any of the antibodies. These results suggest that distinct properties beside ligand antagonism are required for anti-RON mAbs to exert antitumor effects in vivo.  相似文献   
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