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221.
Seyedeh Laili Mohebbi-Nozar Wan Ruslan Ismail Mohamad Pauzi Zakaria Mohammad Seddiq Mortazavi Mohammad Ali Zahed Ali Jahanlu 《人类与生态风险评估》2014,20(5):1164-1176
Levels of polychlorinated biphenyls (PCBs) congeners and dichlorodiphenyltrichloroethane and its metabolites (DDTs) were measured in 18 species of fish, crab, shrimp, and bivalve samples collected from the northern region of the Persian Gulf in Iran. The levels of ∑PCBs varied from 259.92 ± 31.04 ng/g to 1648.88 ± 176.96 ng/g in lipid weight. CB118 showed the highest concentration. ∑DDT variations ranged from ND to 570.45 ± 806.74 ng/g in lipid weight. Health risk was assessed by estimating both dietary intakes and screening values (SVs). Daily intake levels were much lower than the Food and Agriculture Organization (FAO)/World Health Organization (WHO) standards for PCBs and DDTs. Based on an average bodyweight of 73 kg and consumption rates of 0.055 kg/person. day, the SVs for the carcinogen and non-carcinogen effects of PCB and DDT were calculated. Average concentrations of PCBs and DDTs showed that the levels of PCBs exceeded the established SV for carcinogens. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory. 相似文献
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TRIM retrotransposons occur in apple and are polymorphic between varieties but not sports 总被引:8,自引:0,他引:8
Antonius-Klemola K Kalendar R Schulman AH 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(6):999-1008
Retrotransposon markers have been demonstrated to be powerful tools for investigating linkage, evolution and genetics diversity
in plants. In the present study, we identified and cloned three full-size TRIM (terminal-repeat retrotransposon in miniature)
group retrotransposon elements from apple (Malus domestica) cv. ‘Antonovka’, the first from the Rosaceae. To investigate their utility as markers, we designed primers to match the
long terminal repeats (LTRs) of the apple TRIM sequences. We found that PCR reactions with even a single primer produced multiple
bands, suggesting that the copy number of these TRIM elements is relatively high, and that they may be locally clustered or
nested in the genome. Furthermore, the apple TRIM primers employed in IRAP (inter-retrotransposon amplified polymorphism)
or REMAP (retrotransposon-microsatellite amplified polymorphism) analyses produced unique, reproducible profiles for 12 standard
apple cultivars. On the other hand, all seven of the sport mutations in this study were identical to their mother cultivar.
Genetic similarity values calculated from the IRAP/REMAP analyses or the STMS (sequence tagged microsatellite sites) analysis
were generally comparable. PAUP cluster analysis based on IRAP and REMAP markers in apple and Japanese quince generated an
NJ tree that is in good accordance with both a tree based on SMTS markers and the origin of the studied samples. Our results
demonstrate that, although they do not encode the proteins necessary to carry out a life cycle and are thereby non-autonomous,
TRIMs are at least as polymorphic in their insertion patterns as conventional complete retrotransposons.
Kristiina Antonius-Klemola, Ruslan Kalendar are the first two authors contributed equally to this work 相似文献
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226.
Casutt MS Nedielkov R Wendelspiess S Vossler S Gerken U Murai M Miyoshi H Möller HM Steuber J 《The Journal of biological chemistry》2011,286(46):40075-40082
Na(+) is the second major coupling ion at membranes after protons, and many pathogenic bacteria use the sodium-motive force to their advantage. A prominent example is Vibrio cholerae, which relies on the Na(+)-pumping NADH:quinone oxidoreductase (Na(+)-NQR) as the first complex in its respiratory chain. The Na(+)-NQR is a multisubunit, membrane-embedded NADH dehydrogenase that oxidizes NADH and reduces quinone to quinol. Existing models describing redox-driven Na(+) translocation by the Na(+)-NQR are based on the assumption that the pump contains four flavins and one FeS cluster. Here we show that the large, peripheral NqrA subunit of the Na(+)-NQR binds one molecule of ubiquinone-8. Investigations of the dynamic interaction of NqrA with quinones by surface plasmon resonance and saturation transfer difference NMR reveal a high affinity, which is determined by the methoxy groups at the C-2 and C-3 positions of the quinone headgroup. Using photoactivatable quinone derivatives, it is demonstrated that ubiquinone-8 bound to NqrA occupies a functional site. A novel scheme of electron transfer in Na(+)-NQR is proposed that is initiated by NADH oxidation on subunit NqrF and leads to quinol formation on subunit NqrA. 相似文献
227.
Boilard E Larabee K Shnayder R Jacobs K Farndale RW Ware J Lee DM 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(7):4361-4366
In addition to the well-described role of platelets in thrombosis, a growing body of evidence implicates platelets in diverse inflammatory responses. We recently showed platelets can contribute to the pathophysiology of inflammatory arthritis via IL-1- containing microparticles. In this study, we demonstrate that platelets, and not platelet microparticles, actively contribute to synovitis via production of proinflammatory prostacyclin in an autoimmune arthritis model. Using both genetic and pharmacologic approaches, we establish that paracrine production of prostacyclin proceeds in the absence of cyclooxygenase-2. Furthermore, we also demonstrate that prostacyclin generation can arise via transcellular collaboration between platelets and fibroblast-like synoviocytes. In addition to shedding light on an unappreciated pathway of lipid synthesis in arthritis, we further delineate a novel effector activity by which platelets can contribute to inflammatory disease. 相似文献
228.
Hlushchuk R Makanya AN Djonov V 《The International journal of developmental biology》2011,55(4-5):563-567
Inhibitors of angiogenesis and radiation induce compensatory changes in the tumor vasculature both during and after cessation of treatment. In numerous preclinical studies, angiogenesis inhibitors were shown to be efficient in the treatment of many pathological conditions, including solid cancers. In most clinical trials, however, this approach turned out to have no significant effect, especially if applied as monotherapy. Recovery of tumors after therapy is a major problem in the management of cancer patients. The mechanisms underlying tumor recovery (or therapy resistance) have not yet been explicitly elucidated. This review deals with the transient switch from sprouting to intussusceptive angiogenesis, which may be an adaptive response of tumor vasculature to cancer therapy that allows the vasculature to maintain its functional properties. Potential candidates for molecular targeting of this angioadaptive mechanism are yet to be elucidated in order to improve the currently poor efficacy of contemporary antiangiogenic therapies. 相似文献
229.
Dynamic changes in the copy number of pluripotency and cell proliferation genes in human ESCs and iPSCs during reprogramming and time in culture 总被引:2,自引:0,他引:2
Laurent LC Ulitsky I Slavin I Tran H Schork A Morey R Lynch C Harness JV Lee S Barrero MJ Ku S Martynova M Semechkin R Galat V Gottesfeld J Izpisua Belmonte JC Murry C Keirstead HS Park HS Schmidt U Laslett AL Muller FJ Nievergelt CM Shamir R Loring JF 《Cell Stem Cell》2011,8(1):106-118
Genomic stability is critical for the clinical use of human embryonic and induced pluripotent stem cells. We performed high-resolution SNP (single-nucleotide polymorphism) analysis on 186 pluripotent and 119 nonpluripotent samples. We report a higher frequency of subchromosomal copy number variations in pluripotent samples compared to nonpluripotent samples, with variations enriched in specific genomic regions. The distribution of these variations differed between hESCs and hiPSCs, characterized by large numbers of duplications found in a few hESC samples and moderate numbers of deletions distributed across many hiPSC samples. For hiPSCs, the reprogramming process was associated with deletions of tumor-suppressor genes, whereas time in culture was associated with duplications of oncogenic genes. We also observed duplications that arose during a differentiation protocol. Our results illustrate the dynamic nature of genomic abnormalities in pluripotent stem cells and the need for frequent genomic monitoring to assure phenotypic stability and clinical safety. 相似文献
230.