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101.
HYUK JE LEE ELIZABETH G. BOULDING 《Biological journal of the Linnean Society. Linnean Society of London》2010,100(3):494-505
Natural populations of widely‐distributed animals often exhibit clinal variation in phenotypic traits or in allele frequencies of a particular gene over their geographical range. A planktotrophic intertidal snail, Littorina keenae is broadly distributed along the north‐eastern Pacific coast through a large latitudinal range (24°50′N–43°18′N). We tested for latitudinal clines in two complex phenotypic traits – thermal tolerance and body size – and one single locus trait – heat shock cognate 70 (HSC70) – in L. keenae along almost its entire geographical range. We found only weak evidence for a latitudinal cline in the thermal tolerance and no evidence for a cline in allele frequencies at HSC70. However, as predicted by Bergmann's rule, we detected a strong latitudinal cline that accounted for 60% of the variance in body size (R2 = 0.598; P < 0.001). In contrast, body size did not significantly affect thermal tolerance. HSC70 showed no genetic differentiation among the populations, supporting our previous mitochondrial gene‐based estimate of high gene flow during this snail's free‐swimming larval stage. Given that L. keenae experiences panmixia along its species range, the observed size cline may be partially or entirely caused by a phenotypically plastic response to local thermal environments rather than by genetic divergence in body size among populations in response to locally optimizing natural selection. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 494–505. 相似文献
102.
Adams DR Bentley JM Benwell KR Bickerdike MJ Bodkin CD Cliffe IA Dourish CT George AR Kennett GA Knight AR Malcolm CS Mansell HL Misra A Quirk K Roffey JR Vickers SP 《Bioorganic & medicinal chemistry letters》2006,16(3):677-680
A series of 1-(1-pyrrolo(iso)quinolinyl)-2-propylamines was synthesised and evaluated as 5-HT(2C) receptor agonists for the treatment of obesity. The general methods of synthesis of the precursor indoles are described. The functional efficacy and radioligand binding data for the compounds at 5-HT(2) receptor subtypes are reported. The analogue which showed the highest 5-HT(2C) binding affinity (27, 1.6nM) was found to be successful in reducing food intake in rats. 相似文献
103.
Torres AM Tsampazi M Tsampazi C Kennett EC Belov K Geraghty DP Bansal PS Alewood PF Kuchel PW 《FEBS letters》2006,580(6):1587-1591
The presence of d-amino-acid-containing polypeptides, defensin-like peptide (DLP)-2 and Ornithorhyncus venom C-type natriuretic peptide (OvCNP)b, in platypus venom suggested the existence of a mammalian d-amino-acid-residue isomerase(s) responsible for the modification of the all-l-amino acid precursors. We show here that this enzyme(s) is present in the venom gland extract and is responsible for the creation of DLP-2 from DLP-4 and OvCNPb from OvCNPa. The isomerisation reaction is freely reversible and under well defined laboratory conditions catalyses the interconversion of the DLPs to full equilibration. The isomerase is approximately 50-60 kDa and is inhibited by methanol and the peptidase inhibitor amastatin. This is the first known l-to-d-amino-acid-residue isomerase in a mammal. 相似文献
104.
Laboratory bioassays of overwintering field populations of the California red scale parasitoidAphytis melinus DeBach showed a shift in sex ratio of F1 progeny after prolonged exposure to winter temperatures in Tulare County, California. In 7 of 8 tests, short-term winter
field exposure (<75 days) did not result in a significant male bias in sex ratios of F1 progeny when compared to sex ratios observed in laboratory cultures maintained at 27°C. Long term exposure (109–139 days),
however, resulted in significantly (P<0.05) higher male bias in F1 sex ratios in 5 of 6 tests. These results from field populations ofA. melinus agree with conclusions of low temperature laboratory tests onAphytis species (lingnanensis, melinus) by other workers.
Mention of a proprietary or commercial product in this paper does not constitute an endorsement of this product by the University
of California. 相似文献
105.
106.
107.
Modulation of the redox state of tubulin by the glutathione/glutaredoxin reductase system 总被引:7,自引:0,他引:7
Landino LM Moynihan KL Todd JV Kennett KL 《Biochemical and biophysical research communications》2004,314(2):555-560
Alterations in the redox status of proteins have been implicated in the pathology of several neurodegenerative diseases. We report that peroxynitrite-induced disulfides in porcine brain tubulin are repaired by the glutaredoxin reductase system composed of glutathione reductase, human or Escherichia coli glutaredoxin, reduced glutathione, and NADPH. Reduction of disulfide bonds between the alpha- and beta-tubulin subunits by the glutathione reductase system was assessed by Western blot. Tubulin cysteine oxidation and reduction was quantitated by monitoring the incorporation of 5-iodoacetamido-fluorescein, a thiol-specific labeling reagent. Tubulin disulfide bond reduction by the glutaredoxin reductase system restored tubulin polymerization activity that was lost following peroxynitrite addition. In support of redox modulations of tubulin by glutathione, thiol-disulfide exchange between tubulin and oxidized glutathione was detected and quantitated by HPLC. In addition, glutathionylation of tubulin was detected by dot blot using an anti-GSH antibody. 相似文献
108.
W H Cooke I V Ames JE A A Crossman J F Cox T A Kuusela K U Tahvanainen L B Moon J Drescher F J Baisch T Mano B D Levine C G Blomqvist D L Eckberg 《Journal of applied physiology》2000,89(3):1039-1045
We studied three Russian cosmonauts to better understand how long-term exposure to microgravity affects autonomic cardiovascular control. We recorded the electrocardiogram, finger photoplethysmographic pressure, and respiratory flow before, during, and after two 9-mo missions to the Russian space station Mir. Measurements were made during four modes of breathing: 1) uncontrolled spontaneous breathing; 2) stepwise breathing at six different frequencies; 3) fixed-frequency breathing; and 4) random-frequency breathing. R wave-to-R wave (R-R) interval standard deviations decreased in all and respiratory frequency R-R interval spectral power decreased in two cosmonauts in space. Two weeks after the cosmonauts returned to Earth, R-R interval spectral power was decreased, and systolic pressure spectral power was increased in all. The transfer function between systolic pressures and R-R intervals was reduced in-flight, was reduced further the day after landing, and had not returned to preflight levels by 14 days after landing. Our results suggest that long-duration spaceflight reduces vagal-cardiac nerve traffic and decreases vagal baroreflex gain and that these changes may persist as long as 2 wk after return to Earth. 相似文献
109.
Roberto De Pascalis Lara Mittereder Alicia Y. Chou Nikki J. Kennett Karen L. Elkins 《PloS one》2015,10(5)
In the last decade several new vaccines against Francisella tularensis, which causes tularemia, have been characterized in animal models. Whereas many of these vaccine candidates showed promise, it remains critical to bridge the preclinical studies to human subjects, ideally by taking advantage of correlates of protection. By combining in vitro intramacrophage LVS replication with gene expression data through multivariate analysis, we previously identified and quantified correlative T cell immune responses that discriminate vaccines of different efficacy. Further, using C57BL/6J mice, we demonstrated that the relative levels of gene expression vary according to vaccination route and between cell types from different organs. Here, we extended our studies to the analysis of T cell functions of BALB/cByJ mice to evaluate whether our approach to identify correlates of protection also applies to a Th2 dominant mouse strain. BALB/cByJ mice had higher survival rates than C57BL/6J mice when they were immunized with suboptimal vaccines and challenged. However, splenocytes derived from differentially vaccinated BALB/cByJ mice controlled LVS intramacrophage replication in vitro in a pattern that reflected the hierarchy of protection observed in C57BL/6J mice. In addition, gene expression of selected potential correlates revealed similar patterns in splenocytes of BALB/cByJ and C57BL/6J mice. The different survival patterns were related to B cell functions, not necessarily to specific antibody production, which played an important protective role in BALB/cByJ mice when vaccinated with suboptimal vaccines. Our studies therefore demonstrate the range of mechanisms that operate in the most common mouse strains used for characterization of vaccines against F. tularensis, and illustrate the complexity necessary to define a comprehensive set of correlates. 相似文献
110.
Michaël C Fontaine Stuart JE Baird Sylvain Piry Nicolas Ray Krystal A Tolley Sarah Duke Alexei Birkun Jr Marisa Ferreira Thierry Jauniaux Ángela Llavona Bayram Öztürk Ayaka A Öztürk Vincent Ridoux Emer Rogan Marina Sequeira Ursula Siebert Gísli A Vikingsson Jean-Marie Bouquegneau Johan R Michaux 《BMC biology》2007,5(1):1-16