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991.
992.
Raffaella Di Lisi Anne Picard Simonetta Ausoni Stefano Schiaffino 《BMC molecular biology》2007,8(1):78
Background
We reported previously that the cardiac troponin I (cTnI) promoter drives cardiac-specific expression of reporter genes in cardiac muscle cells and in transgenic mice, and that disruption of GATA elements inactivates the cTnI promoter in cultured cardiomyocytes. We have now examined the role of cTnI promoter GATA elements in skeletal muscle cells. 相似文献993.
Cinzia Comino Sergio Lanteri Ezio Portis Alberto Acquadro Annalisa Romani Alain Hehn Romain Larbat Frédéric Bourgaud 《BMC plant biology》2007,7(1):14
Background
Cynara cardunculus L. is an edible plant of pharmaceutical interest, in particular with respect to the polyphenolic content of its leaves. It includes three taxa: globe artichoke, cultivated cardoon, and wild cardoon. The dominating phenolics are the di-caffeoylquinic acids (such as cynarin), which are largely restricted to Cynara species, along with their precursor, chlorogenic acid (CGA). The scope of this study is to better understand CGA synthesis in this plant. 相似文献994.
Balhorn R 《Genome biology》2007,8(9):227
The protamines are a diverse family of small arginine-rich proteins that are synthesized in the late-stage spermatids of many
animals and plants and bind to DNA, condensing the spermatid genome into a genetically inactive state. Vertebrates have from
one to 15 protamine genes per haploid genome, which are clustered together on the same chromosome. Comparison of protamine
gene and amino-acid sequences suggests that the family evolved from specialized histones through protamine-like proteins to
the true protamines. Structural elements present in all true protamines are a series of arginine-rich DNA-anchoring domains
(often containing a mixture of arginine and lysine residues in non-mammalian protamines) and multiple phosphorylation sites.
The two protamines found in mammals, P1 and P2, are the most widely studied. P1 packages sperm DNA in all mammals, whereas
protamine P2 is present only in the sperm of primates, many rodents and a subset of other placental mammals. P2, but not P1,
is synthesized as a precursor that undergoes proteolytic processing after binding to DNA and also binds a zinc atom, the function
of which is not known. P1 and P2 are phosphorylated soon after their synthesis, but after binding to DNA most of the phosphate
groups are removed and cysteine residues are oxidized, forming disulfide bridges that link the protamines together. Both P1
and P2 have been shown to be required for normal sperm function in primates and many rodents. 相似文献
995.
996.
Debra L Fisk Leigh C LattaIV Roland A Knapp Michael E Pfrender 《BMC evolutionary biology》2007,7(1):22
Background
Introduced species can have profound effects on native species, communities, and ecosystems, and have caused extinctions or declines in native species globally. We examined the evolutionary response of native zooplankton populations to the introduction of non-native salmonids in alpine lakes in the Sierra Nevada of California, USA. We compared morphological and life-history traits in populations of Daphnia with a known history of introduced salmonids and populations that have no history of salmonid introductions. 相似文献997.
The effect of abatacept, a selective T-cell co-stimulation modulator, on vaccination has not been previously investigated.
In this open-label, single-dose, randomized, parallel-group, controlled study, the effect of a single 750 mg infusion of abatacept
on the antibody response to the intramuscular tetanus toxoid vaccine (primarily a memory response to a T-cell-dependent peptide
antigen) and the intramuscular 23-valent pneumococcal vaccine (a less T-cell-dependent response to a polysaccharide antigen)
was measured in 80 normal healthy volunteers. Subjects were uniformly randomized to receive one of four treatments: Group
A (control group), subjects received vaccines on day 1 only; Group B, subjects received vaccines 2 weeks before abatacept;
Group C, subjects received vaccines 2 weeks after abatacept; and Group D, subjects received vaccines 8 weeks after abatacept.
Anti-tetanus and anti-pneumococcal (Danish serotypes 2, 6B, 8, 9V, 14, 19F and 23F) antibody titers were measured 14 and 28
days after vaccination. While there were no statistically significant differences between the dosing groups, geometric mean
titers following tetanus or pneumococcal vaccination were generally lower in subjects who were vaccinated 2 weeks after receiving
abatacept, compared with control subjects. A positive response (defined as a twofold increase in antibody titer from baseline)
to tetanus vaccination at 28 days was seen, however, in ≥ 60% of subjects across all treatment groups versus 75% of control
subjects. Similarly, over 70% of abatacept-treated subjects versus all control subjects (100%) responded to at least three
pneumococcal serotypes, and approximately 25–30% of abatacept-treated subjects versus 45% of control subjects responded to
at least six serotypes. 相似文献
998.
Background
Enzymes involved in DNA metabolic events of the highly radioresistant bacterium Deinococcus radiodurans are currently examined to understand the mechanisms that protect and repair the Deinococcus radiodurans genome after extremely high doses of γ-irradiation. Although several Deinococcus radiodurans DNA repair enzymes have been characterised, no biochemical data is available for DNA ligation and DNA endhealing enzymes of Deinococcus radiodurans so far. DNA ligases are necessary to seal broken DNA backbones during replication, repair and recombination. In addition, ionizing radiation frequently leaves DNA strand-breaks that are not feasible for ligation and thus require end-healing by a 5'-polynucleotide kinase or a 3'-phosphatase. We expect that DNA ligases and end-processing enzymes play an important role in Deinococcus radiodurans DNA strand-break repair. 相似文献999.
Cédric MessaoudiI Thomas Boudier Carlos Oscar Sanchez Sorzano Sergio Marco 《BMC bioinformatics》2007,8(1):288
Background
Transmission electron tomography is an increasingly common three-dimensional electron microscopy approach that can provide new insights into the structure of subcellular components. Transmission electron tomography fills the gap between high resolution structural methods (X-ray diffraction or nuclear magnetic resonance) and optical microscopy. We developed new software for transmission electron tomography, TomoJ. TomoJ is a plug-in for the now standard image analysis and processing software for optical microscopy, ImageJ. 相似文献1000.
The sequencing of the genome of a female rhesus macaque (Macaca mulatta) of Indian origin will provide us with biomedical and evolutionary insights into both humans and Old World monkeys. 相似文献