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101.
Tsukamoto H Yokoyama Y Suzuki T Mizuta S Yoshinaka R 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,148(3):225-230
In teleosts, two distinct types of TIMP-2s occur, TIMP-2a and TIMP-2b, but little is known about their locations and quantitative expressions. Here, we examined pufferfish (Takifugu rubripes) TIMP-2a (fgTIMP-2a) and TIMP-2b (fgTIMP-2b) quantities and locations in fugu adult tissues and embryos. To compare the quantitative expression of fgTIMP-2s, we performed a quantitative real-time PCR (qPCR). FgTIMP-2a mRNA was constitutively expressed and significant differences in expression were not observed among adult tissues. Whereas, fgTIMP-2b mRNA was significantly differently expressed in ordinary muscle and gill compared to the expression level in whole blood (P<0.05). Although significant difference was not observed between brain and other tissues, both fgTIMP-2s mRNAs were abundant in the brain. In addition, we examined embryos during development using qPCR. Both fgTIMP-2s mRNAs gradually increased during embryonic development from 48 hpf. However, fgTIMP-2b mRNA was obviously abundant compared to fgTIMP-2a mRNA in embryos. We also examined the specific mRNA distribution in embryos. The fgTIMP-2s mRNAs showed the same distribution during development. Both fgTIMP-2s are expressed in adult fugu tissues and embryos but their expression levels clearly differ, suggesting that there is a predominance of fgTIMP-2b over fgTIMP-2a in vivo. 相似文献
102.
103.
Early‐shared Mycobacterium bovis bacillus Calmette–Guérin sub‐strains induce Th1 cytokine production in vivo 下载免费PDF全文
Keiichi Taniguchi Yuuji Miyatake Daisuke Hayashi Atsuro Takami Saotomo Itoh Saburo Yamamoto Shigeaki Hida Kikuo Onozaki Takemasa Takii 《Microbiology and immunology》2015,59(11):684-689
104.
105.
N-Methylimidazolium chloride is found to catalyze a coupling reaction between monophosphates and activated phosphorous-nitrogen intermediates such as a phosphorimidazolide and phosphoromorpholidate to form biologically important unsymmetrical pyrophosphate diesters. The catalyst is much more active, cheaper, and less explosive than 1H-tetrazole, known as the best catalyst for the pyrophosphate formation over a decade. The mild and neutral reaction conditions are compatible with allylic pyrophosphate formation in Lipid I syntheisis. 31P NMR experiments suggest that the catalyst acts not only as an acid but also as a nucleophile to form cationic and electrophilic phosphor-N-methylimidazolide intermediates in the pyrophosphate formation. 相似文献
106.
107.
Orihara K Yamazaki T Shinkyo R Sakaki T Inouye K Tsukamoto A Sugiura J Shishido K 《Applied microbiology and biotechnology》2005,69(1):22-28
Rat cytochrome P450, CYP1A1, has been reported to play an important role in the metabolism of mono-trichlorodibenzo-p-dioxins (M-TriCDDs). To breed lignin (and M-TetraCDDs)-degrading basidiomycete Coriolus hirsutus strains producing rat CYP1A1, an expression cassette [C. hirsutus gpd promoter-C. hirsutus gpd 5′ portion (224-bp of 1st exon–8th base of 4th exon)-rat cyp1a1 cDNA-Lentinula edodes priA terminator] was constructed and inserted into pUCR1 carrying the C. hirsutus arg1 gene. The resulting recombinant plasmid, MIp5-(cyp1a1 + arg1) was introduced into protoplasts of C. hirsutus monokaryotic strain OJ1078 (Arg−, Leu−), obtaining three good Arg+ transformants. These transformants [ChTF5-2(CYP1A1), ChTF5-4(CYP1A1), and ChTF5-6(CYP1A1)] were estimated to carry nine, six, and seven copies of the expression cassette on their chromosomes, respectively. Immunoblot analysis revealed that the three transformants produce similar amounts of rat CYP1A1 enzyme. ChTF5-2(CYP1A1), ChTF5-4(CYP1A1), ChTF5-6(CYP1A1) and recipient OJ1078 were cultivated in a liquid medium containing 2,7/2,8(at a ratio of 1:1)-dichlorodibenzo-p-dioxins (2,7/2,8-DCDDs) and the amount of intra- and extracellular 2,7/2,8-DCDDs remaining was measured. The results showed that all three transformants efficiently transform 2,7/2,8-DCDDs through the action of the recombinant rat CYP1A1 enzyme. 相似文献
108.
Unprecedented intraspecific diversity of the MHC class I region of a teleost medaka, Oryzias latipes
Tsukamoto K Hayashi S Matsuo MY Nonaka MI Kondo M Shima A Asakawa S Shimizu N Nonaka M 《Immunogenetics》2005,57(6):420-431
The major histocompatibility complex (MHC) is present at a single chromosomal locus of all jawed vertebrate analyzed so far,
from sharks to mammals, except for teleosts whose orthologs of the mammalian MHC-encoded genes are dispersed at several chromosomal
loci. Even in teleosts, several class IA genes and those genes directly involved in class I antigen presentation preserve
their linkage, defining the teleost MHC class I region. We determined the complete nucleotide sequence of the MHC class I
region of the inbred HNI strain of medaka, Oryzias latipes (northern Japan population-derived), from four overlapping bacterial artificial chromosome (BAC) clones spanning 540,982 bp,
and compared it with the published sequence of the corresponding region of the inbred Hd-rR strain of medaka (425,935 bp,
southern Japan population-derived) as the first extensive study of intraspecies polymorphisms of the ectotherm MHC regions.
A segment of about 100 kb in the middle of the compared sequences encompassing two class Ia genes and two immunoproteasome
subunit genes, PSMB8 and PSMB10, was so divergent between these two inbred strains that a reliable sequence alignment could not be made. The rest of the
compared region (about 320 kb) showed a fair correspondence, and an approximately 96% nucleotide identity was observed upon
gap-free segmental alignment. These results indicate that the medaka MHC class I region contains an ∼100-kb polymorphic core,
which is most probably evolving adaptively by accumulation of point mutations and extensive genetic rearrangements such as
insertions, deletions and duplications.
The nucleotide sequence data of HNI MHC class I region reported in this paper have been submitted to the DDBJ/EMBL/GenBank
and were assigned the accession number AB183488. 相似文献
109.
Control of mRNA translation preserves endoplasmic reticulum function in beta cells and maintains glucose homeostasis 总被引:18,自引:0,他引:18
Scheuner D Vander Mierde D Song B Flamez D Creemers JW Tsukamoto K Ribick M Schuit FC Kaufman RJ 《Nature medicine》2005,11(7):757-764
Type 2 diabetes is a disorder of hyperglycemia resulting from failure of beta cells to produce adequate insulin to accommodate an increased metabolic demand. Here we show that regulation of mRNA translation through phosphorylation of eukaryotic initiation factor 2 (eIF2alpha) is essential to preserve the integrity of the endoplasmic reticulum (ER) and to increase insulin production to meet the demand imposed by a high-fat diet. Accumulation of unfolded proteins in the ER activates phosphorylation of eIF2alpha at Ser51 and inhibits translation. To elucidate the role of this pathway in beta-cell function we studied glucose homeostasis in Eif2s1(tm1Rjk) mutant mice, which have an alanine substitution at Ser51. Heterozygous (Eif2s1(+/tm1Rjk)) mice became obese and diabetic on a high-fat diet. Profound glucose intolerance resulted from reduced insulin secretion accompanied by abnormal distension of the ER lumen, defective trafficking of proinsulin, and a reduced number of insulin granules in beta cells. We propose that translational control couples insulin synthesis with folding capacity to maintain ER integrity and that this signal is essential to prevent diet-induced type 2 diabetes. 相似文献
110.
Role of Helicobacter pylori in gastric carcinogenesis: the origin of gastric cancers and heterotopic proliferative glands in Mongolian gerbils 总被引:7,自引:0,他引:7
Helicobacter pylori infection is well accepted to be a very important factor for the development of gastric carcinogenesis in the human stomach. In Mongolian gerbils treated with chemical carcinogens, H. pylori infection enhances glandular stomach carcinogenesis, and eradication of infection and results in curtailment of enhancing effects, particularly at early stages of associated inflammation. A high-salt diet exacerbates the effects of H. pylori infection on gastric carcinogenesis, and these two factors act synergistically to promote the development of gastric cancers in this animal model. However, the bacterium exerts the greater effects. Early acquisition significantly increases gastric chemical carcinogenesis in Mongolian gerbils, as compared to later infection. While heterotopic proliferative glands, hyperplastic and dilated glands localized beneath the muscularis mucosae, frequently develop with H. pylori infection alone in this animal model, they obviously regress on eradication, suggesting a relation to severe gastritis, rather than a malignant character. Furthermore, endocrine cells, positive for chromogranin A, are observed in the heterotopic proliferative glands, in contrast to cancerous lesions which lack endocrine elements. In conclusion, H. pylori is not an initiator, but rather a strong promoter of gastric carcinogenesis, whose eradication, together with reduction in salt intake, might effectively prevent gastric cancer development. 相似文献