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71.
Anukulkitch C Rao A Dunshea FR Blache D Lincoln GA Clarke IJ 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(1):R242-R252
We studied the effects of photoperiod on metabolic profiles, adiposity, and gene expression of hypothalamic appetite-regulating peptides in gonad-intact and castrated Soay rams. Groups of five to six animals were studied 6, 18, or 30 wk after switching from long photoperiod (LP: 16 h of light) to short photoperiod (SP: 8 h of light). Reproductive and metabolic indexes were measured in blood plasma. Expression of neuropeptide Y (NPY), proopiomelanocortin (POMC), and leptin receptor (ObRb) in the arcuate nucleus was measured using in situ hybridization. Testosterone levels of intact animals were low under LP, increased to a peak at 16 wk under SP, and then declined. Voluntary food intake (VFI) was high under LP in both intact and castrated animals, decreased to a nadir at 12-16 wk under SP, and then recovered, but only in intact rams as the reproductive axis became photorefractory to SP. NPY gene expression varied positively and POMC expression varied negatively with the cycle in VFI, with differences between intact and castrate rams in the refractory phase. ObRb expression decreased under SP, unrelated to changes in VFI. Visceral fat weight also varied between the intact and castrated animals across the cycle. We conclude that 1) photoperiodic changes in VFI reflect changes in NPY and POMC gene expression, 2) changes in ObRb gene expression are not necessarily determinants of changes in VFI, 3) gonadal status affects the pattern of VFI that changes with photoperiod, and 4) in the absence of gonadal factors, animals can eat less but gain adiposity. 相似文献
72.
Simulation and experiment have been used to establish that significant artifacts can be generated in X-pulse CPMG relaxation dispersion experiments recorded on heteronuclear ABX spin-systems, such as 13C
i
–13C
j
–1H, where 13C
i
and 13C
j
are strongly coupled. A qualitative explanation of the origin of these artifacts is presented along with a simple method
to significantly reduce them. An application to the measurement of 1H CPMG relaxation dispersion profiles in an HIV-2 TAR RNA molecule where all ribose sugars are protonated at the 2′ position,
deuterated at all other sugar positions and 13C labeled at all sugar carbons is presented to illustrate the problems that strong 13C–13C coupling introduces and a simple solution is proposed. 相似文献
73.
Amit G Deshwar Shankar Vembu Christina K Yung Gun Ho Jang Lincoln Stein Quaid Morris 《Genome biology》2015,16(1)
Tumors often contain multiple subpopulations of cancerous cells defined by distinct somatic mutations. We describe a new method, PhyloWGS, which can be applied to whole-genome sequencing data from one or more tumor samples to reconstruct complete genotypes of these subpopulations based on variant allele frequencies (VAFs) of point mutations and population frequencies of structural variations. We introduce a principled phylogenic correction for VAFs in loci affected by copy number alterations and we show that this correction greatly improves subclonal reconstruction compared to existing methods. PhyloWGS is free, open-source software, available at https://github.com/morrislab/phylowgs.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0602-8) contains supplementary material, which is available to authorized users. 相似文献74.
Kittilson JD Slagter BJ Martin LE Sheridan MA 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2011,160(2):237-244
In this study, cDNA for a somatostatin receptor variant (somatostatin receptor subtype 2, SSTR 2) was isolated, cloned, and sequenced from rainbow trout. A 1821-nt cDNA was isolated and found to contain a single initiation site 387-nt from the most 5' end, an open reading frame of 1116-nt, and a single putative polyadenylation site 189-nt from the most 3' end. The encoded protein contains 372 amino acids and contains seven membrane-spanning domains. Based on structural analysis, the protein was identified as a subtype 2 SSTR. These data support the emergence of a multigenic SSTR family early in the course of vertebrate evolution, concomitant with or perhaps prior to the divergence of boney fish. The distribution of SSTR 2 mRNA in tissues was determined by quantitative real time-PCR (QRT-PCR). SSTR 2 was most abundant in the brain (where it was detected in the telencephalon, optic tectum, and hypothalamus), skeletal muscle, and liver, but it also was present in the endocrine pancreas (Brockmann body) and various regions of the gastrointestinal tract (esophagus, stomach, intestine). SSTR 2 mRNA was most abundant in the brain, muscle, and liver. In vitro the Brockmann body and liver with increasing concentrations of glucose (1, 4, 10mM) resulted in increased expression of SSTR 2 mRNA. These findings contribute to the understanding of the evolution of the SSTR family and provide insight into the roles of SSTR 2 in fish. 相似文献
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79.
D. C. R. Lincoln 《Journal of Zoology》1965,145(1):9-17
Eggs of Culex pipiens L. are laid in rafts on the surface of still or slow moving water, whereas those of Mansonia africana (Theobold) are deposited beneath tho surface of the water on the undersides of floating leaves (Laurence & Smith 1958; Laurence 1959). The eggs of both species are surrounded by air, those of Culex pipiens are in direct contact with the external atmosphere, whereas those of Mansonia africana are partially surrounded by a bubble of air trapped between them. The anterior onds of the eggs of Mansonia africana project through the bubble of air into the surrounding water. This bubble of air is only found around living eggs and disappears if tho eggs die and shortly before they hatch. Iyengar (1935) has shown that the eggs of Ficalba minima Theo. although often deposited on the same leaf as those of Mansonioides , are laid above the water line and resemble in structure those of Culex and Coquillettidia . The structure of the egg-shell of both Culez pipiens and Mansonia africana is described and discussed. 相似文献
80.