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51.
Hada N Shida Y Shimamura H Sonoda Y Kasahara T Sugita M Takeda T 《Carbohydrate research》2008,343(13):2221-2228
Two types of amphoteric glycosphingolipid found in the earthworm Pheretima hilgendorfi, PC(-->6)-beta-d-Galp-(1-->6)-beta-d-Galp-(1-->1)Cer (1) and PC(-->6)-beta-d-Galp-(1-->6)-beta-d-Galp-(1-->6)-beta-d-Galp-(1-->1)Cer (2), and their derivatives (4, 5) were synthesized. These were examined for their ability to enhance production of interleukin-8 (IL-8), a potent inflammatory cytokine involved in neutrophil chemotaxis, in a TNFalpha-stimulated granulocytic HL-60 cells. Compounds 1 and 2 were found to be potent enhancers of IL-8 production. 相似文献
52.
Itonori S Yamawaki S Aoki K Yamamoto K Hada N Takeda T Dulaney JT Sugita M 《Glycobiology》2008,18(7):540-548
Edible fungi, mushrooms, are a popular food in Japan and over 15 cultured mushroom species are available at the food markets. Recently, constituents or ingredients of edible mushrooms have drawn attention because possibilities have been seen for their medical usage. Mycoglycolipids (basidiolipids) of higher mushrooms have been characterized as glycosylinositolphosphoceramides, having a common core structure of Manalpha1-2Ins1-[PO(4)]-Cer and extensions of Man, Gal, and/or Fuc sugar moieties. Seven mycoglycolipids were purified from the edible mushroom Hypsizygus marmoreus by successive column chromatography on ion exchange Sephadex (DEAE-Sephadex) and silicic acid (Iatrobeads). Their structures were characterized to be Ins1-[PO(4)]-Cer (AGL0), Manalpha1-2Ins1-[PO(4)]-Cer (AGL1), Galbeta1-6Manalpha1-2Ins1-[PO(4)]-Cer (AGL2), Fucalpha1- 2Galbeta1-6Manalpha1-2Ins1-[PO(4)]-Cer (AGL3), Galalpha1-3(Fucalpha1-2)Galbeta1-6Manalpha1-2Ins1-[PO(4)]-Cer (AGL4), Galalpha1-2Galalpha1-3(Fucalpha1-2)Galbeta1-6Manalpha1-2Ins1-[PO(4)]-Cer (AGL5), and Galalpha1-2Galalpha1-2Galalpha1-3(Fucalpha1-2)Galbeta1-6Manalpha1-2Ins1-[PO(4)]-Cer (AGL6) by sugar compositional analysis, methylation analysis, periodate oxidation, partial acid hydrolysis, enzymatic hydrolysis, immunochemical analysis, gas-liquid chromatography (GC), gas chromatography-mass spectrometry (GC-MS), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), and (1)H-nuclear magnetic resonance spectroscopy (NMR). Ceramide constituents of their mycoglycolipids were composed of phytosphingosine as the sole sphingoid, and mainly 2-hydroxy C22:0 and C24:0 acids as the fatty acids. By immunochemical detection, the terminal structure of AGL4, Galalpha1-3(Fucalpha1-2)Galbeta-, was shown to have blood group type B activity. Galalpha1-2 and its repeating sequence in AGL5 and AGL6 are novel structures on the nonreducing sugar end in mycoglycolipids. These two mycoglycolipids in H. marmoreus distinguish it from other basidiomycetes. 相似文献
53.
The Japenese eel, Anguilla japonica, is generally assumed to be composed of a single population with wide distribution range, and some genetic studies using allozyme or mitochondrial DNA methods supported this population model. However, one genetic study suggested the existence of multiple populations in this species, and thus, more detailed studies on the population structure is needed. Here we characterized a total of 11 microsatellite markers of the Japanese eel. These will serve as powerful tools for detailed population study for the Japanese eel, though two of them showed the significant departure from the Hardy–Weinberg expectations. 相似文献
54.
Hiroyasu Miyazaki Mutsumi Yoshida Keiji Samura Hiroyoshi Matsumoto Fumihiko Ikemoto Masahiro Tagawa 《Experimental Animals》2002,51(1):95-98
Ranges in diurnal variation and the patterns of body temperature (T), blood pressure (BP), heart rate (HR) and locomotor activity (LA) in 61 laboratory beagle dogs were analyzed using a telemetry system. Body temperature, BP, HR and LA increased remarkably at feeding time. Locomotor activity increased sporadically during the other periods. Body temperature was maintained at the higher value after feeding but had decreased by 0.2 C by early the next morning. Blood pressure fell to a lower value after feeding but had increased by 2.8% by early the next morning. Heart rate decreased progressively after feeding and was 14.5% lower the next morning. This study determined that in laboratory beagles the ranges of diurnal variation and patterns of T, BP and HR are significantly different from those reported in humans and rodents, and that over 24 hr these physiological changes were associated with their sporadic wake-sleep cycles of the dogs. 相似文献
55.
For the first step toward resolution of the higher-level relationships of the order Aulopiformes (Teleostei: Eurypterygii)
using longer DNA sequences, we determined the complete mitochondrial DNA sequence for Aulopus japonicus (Aulopodidae). The entire genome was purified by gene amplification using a long PCR technique, and the products were subsequently
used as templates for PCR with 63 fish-versatile and 3 species-specific primers that amplify contiguous, overlapping segments
of the entire genome. Direct sequencing of the PCR products demonstrated that the genome (16 653 base pairs [bp]) contained
the same 37 mitochondrial genes (2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) as found in other vertebrates,
with the gene order identical to that in typical vertebrates. Maximum-parsimony analysis using nucleotide sequences from the
concatenated 12 protein-coding genes (no third codon positions and excluding the ND6 gene) plus 22 tRNA genes (stem regions
only) from eight teleosts placed A. japonicus in a reasonable phylogenetic position; those from individual protein-coding genes and the concatenated 22 tRNA genes alone,
however, did not reproduce the expected phylogeny with few exceptions, probably owing to insufficient phylogenetic information
in these smaller data sets. This result suggests that further taxonomic sampling and sequencing efforts may clarify limits
and intra- and interrelationships of this morphologically and ecologically diverse group of fishes using mitochondrial genomic
(mitogenomic) data.
Received: August 31, 2000 / Revised: December 20, 2000 / Accepted: January 23, 2001 相似文献
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59.
Heme synthase (ferrochelatase) catalyzes the removal of iron from heme and demetalation of metalloporphyrins 总被引:2,自引:0,他引:2
Taketani S Ishigaki M Mizutani A Uebayashi M Numata M Ohgari Y Kitajima S 《Biochemistry》2007,46(51):15054-15061
The red pigments in meat products, including cooked cured ham, arise from the reaction of myoglobin with nitric oxide generated from exogenous nitrite. Since carcinogenic nitrosoamines may be generated by the treatment of meats with nitrite, the production of nitrite-free meat products is an attractive alternative. Raw dry-cured (Parma) hams are produced by the treatment of meats with salts other than nitrite. Analysis of pigments in raw dry-cured hams reveals that the main pigment is zinc protoporphyrin, suggesting that the conversion of heme to zinc protoporphyrin occurs via an iron-removal reaction from myoglobin heme during the processing of raw hams. Purification of the iron-removal enzyme showed that it was identical to ferrochelatase. Recombinant ferrochelatase in combination with NADH-cytochrome b5 reductase catalyzed NADH-dependent iron-removal reaction from hemin and hemoproteins. Metal ions such as zinc and cobalt were also removed from the corresponding metalloporphyrins. The addition of zinc ions led to the formation of zinc protoporphyrin. In cultured cells, the conversion of zinc mesoporphyrin to mesoheme was observed to be dependent on ferrochelatase and could be markedly induced during erythroid differentiation. This is the first demonstration of a new enzyme reaction, the reverse reaction of ferrochelatase, which may contribute to a new route of the recycling of protoporphyrin and heme in cells. 相似文献
60.
We determined the complete nucleotide sequence of the mitochondrial genome (except for a portion of the putative control
region) for a deep-sea fish, Gonostoma gracile. The entire mitochondrial genome was purified by gene amplification using long polymerase chain reaction (long PCR), and the
products were subsequently used as templates for PCR with 30 sets of newly designed, fish-universal primers that amplify contiguous,
overlapping segments of the entire genome. Direct sequencing of the PCR products showed that the genome contained the same
37 mitochondrial structural genes as found in other vertebrates (two ribosomal RNA, 22 transfer RNA, and 13 protein-coding
genes), with the order of all rRNA and protein-coding genes, and 19 tRNA genes being identical to that in typical vertebrates.
The gene order of the three tRNAs (tRNAGlu, tRNAThr, and tRNAPro) relative to cytochrome b, however, differed from that determined in other vertebrates. Two steps of tandem duplication of gene regions, each followed
by deletions of genes, can be invoked as mechanisms generating such rearrangements of tRNAs. This is the first example of
tRNA gene rearrangements in a bony fish mitochondrial genome.
Received August 5, 1998; accepted February 19, 1999. 相似文献