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91.
Generation of a wheat leaf rust, Puccinia triticina, EST database from stage-specific cDNA libraries
92.
CROSS has reported1, 2 chromosome complements in rodents ranging up to 2n=84 (in the North American geomyid Geomys breviceps) and 2n=86 (in the heteromyid Dipodomys merriami). Matthey has contested3 this claim; he maintained that in Geomys bursarius 2n =70 or 72 and he doubted whether a higher number had been confirmed. Numbers in the 2n=70 to 80 range have since been reported4 in several genera of Canidae and Ursidae. In general, rodent chromosomes fall into the lower group numbers but, among murines, Lophuromys aquillus is reported to have a chromosome complement of 70 (ref. 5) and Cricetomys gambianus one of 78 (ref, 6). In the gerbilline, Meriones shawii, the number can vary up to 78 (ref. 7). 相似文献
93.
The polyoma-induced transplantation antigen is virus specific and its presence on polyoma transformed but not normal cells suggested that at least part of the polyoma genome is maintained in tumour cells. Studies reported here indicate that malignancy is not maintained solely by the presence of this transplantation antigen. 相似文献
94.
SV40 virus DNA transcribes differently in vitro from in vivo. In a series of parallel experiments, the in vitro and in vivo single-stranded DNAs are shown to differ in structure. 相似文献
95.
“Spontaneous” Release of Type C Viruses from Clonal Lines of “Spontaneously” Transformed Balb/3T3 Cells 总被引:19,自引:0,他引:19
GEORGE J. TODARO 《Nature: New biology》1972,240(100):157-160
I wish to report that clonal lines of spontaneously transformed Balb/c 3T3 cells can spontaneously release high titres of type C virus in conditions where the untransformed cells do not release type C virus. Further, the spontaneously transformed clones of random-bred Swiss cells, such as 3T6 and 3T12 and an SV40 transformed 3T3 clone have inducible type C viruses, while in the same conditions complete virus production is not detected in the untransformed 3T3 cells. The results suggest that the control of endogenous type C virus information is altered in transformed cells. 相似文献
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ANGELOS ALEXANDROU IOANNIS PAPAEVRIPIDOU KYRIAKOS TSANGARAS IOANNA ALEXANDROU MARIOS TRYFONIDIS VIOLETTA CHRISTOPHIDOU-ANASTASIADOU ELENI ZAMBA-PAPANICOLAOU GEORGE KOUMBARIS VASSOS NEOCLEOUS LEONIDAS A. PHYLACTOU NICOS SKORDIS GEORGE A. TANTELES CAROLINA SISMANI 《Journal of genetics》2016,95(4):839-845
Haploinsufficiency of the short stature homeobox contaning SHOX gene has been shown to result in a spectrum of phenotypes ranging from Leri–Weill dyschondrosteosis (LWD) at the more severe end to SHOX-related short stature at the milder end of the spectrum. Most alterations are whole gene deletions, point mutations within the coding region, or microdeletions in its flanking sequences. Here, we present the clinical and molecular data as well as the potential molecular mechanism underlying a novel microdeletion, causing a variable SHOX-related haploinsufficiency disorder in a three-generation family. The phenotype resembles that of LWD in females, in males, however, the phenotypic expression is milder. The 15523-bp SHOX intragenic deletion, encompassing exons 3–6, was initially detected by array-CGH, followed by MLPA analysis. Sequencing of the breakpoints indicated an Alu recombination-mediated deletion (ARMD) as the potential causative mechanism. 相似文献
99.
CHRISTOPHER GRAHAM LAING TIMOTHY GEORGE SHREEVE DEBORAH MARIE ELIZABETH PEARCE 《Global Change Biology》2008,14(4):916-924
The quantification of greenhouse gas sources and sinks is important to understanding the impact of climate change. Methane (CH4) is a potent greenhouse gas, which, on a global scale, is released largely as a product of anaerobic microbial decomposition and predominantly from wetlands. A zone of intense CH4 production just below the water table is thought to contribute significantly to the overall flux from peat bogs. We describe the use of membrane inlet quadrupole mass spectrometry (QMS) to confirm the existence of bubbles, their gaseous concentrations and their localization at a fine spatial resolution within intact peat cores. We use the distribution of the noble gas argon (Ar) and the distinct QMS responses to dissolved and gaseous (bubble) phases to identify trapped bubbles with a resolution of 0.6 mm. Bubbles with CH4 concentrations of up to 20 kPa were widely distributed in the upper 300 mm of the cores with ~11% of all profiles comprising bubbles. The dissolved concentrations responsible for the bubbles were on average 83±80 μm , indicating lower concentrations relative to other QMS studies. We suggest that if the distinction between dissolved and gaseous phases is not made in studies of CH4 within peat profiles then the prominence of bubbles is likely to result in overestimates of dissolved CH4 concentrations. Fluxes of CH4 from peat as a result of drawdown or other perturbation are likely to be large, rapid and short lived because of bubble burst, and also larger than from peat without bubbles. We suggest that the dynamics of fluxes need to be modelled taking into account both gaseous and dissolved phases. Estimates of potential fluxes that assume CH4 is dissolved are likely to overestimate fluxes if the gaseous phase has not been taken into account. 相似文献
100.
Abstract Human induced alterations to rivers and steams have resulted in significant changes to the structure and diversity of riparian and aquatic plant communities. These changes will impact on the dynamics of riverine carbon cycles and food web structure and function. Here we investigate the principal sources of organic carbon supporting local shredder communities across a gradient in different levels of anthropogenic development along riverine reaches, in South Australia. In forested/wooded reaches with minimum to limited development, semi‐emergent macrophytes were the principal sources of organic carbon supporting the local shredder communities. However, in developed reaches, course particulate organic matter and filamentous algae were the principal food sources. The C:N ratios of the food sources in developed reaches were higher than those of their consumers indicating a stoichiometric mismatch. This imbalanced consumer‐resource nutrient ratio in those developed reaches is likely to impose constraints on the growth and reproduction of their aquatic shredder communities with probable knock‐on effects to higher trophic levels. 相似文献