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91.
Yuasa K Hagiwara Y Ando M Nakamura A Takeda S Hijikata T 《Cell structure and function》2008,33(2):163-169
miR-1, miR-133a, and miR-206 are muscle-specific microRNAs expressed in skeletal muscles and have been shown to contribute to muscle development. To gain insight into the pathophysiological roles of these three microRNAs in dystrophin-deficient muscular dystrophy, their expression in the tibialis anterior (TA) muscles of mdx mice and CXMD(J) dogs were evaluated by semiquantitative RT-PCR and in situ hybridization. Their temporal and spatial expression patterns were also analyzed in C2C12 cells during muscle differentiation and in cardiotoxin (CTX)-injured TA muscles to examine how muscle degeneration and regeneration affect their expression. In dystrophic TA muscles of mdx mice, miR-206 expression was significantly elevated as compared to that in control TA muscles of age-matched B10 mice, whereas there were no differences in miR-1 or miR-133a expression between B10 and mdx TA muscles. On in situ hybridization analysis, intense signals for miR-206 probes were localized in newly formed myotubes with centralized nuclei, or regenerating muscle fibers, but not in intact pre-degenerated fibers or numerous small mononucleated cells, possibly proliferating myoblasts and inflammatory infiltrates. Similar increased expression of miR-206 was also found in C2C12 differentiation and CTX-induced regeneration, in which differentiated myotubes or regenerating fibers showed abundant expression of miR-206. However, CXMD(J) TA muscles contained smaller amounts of miR-206, miR-1, and miR-133a than controls. They exhibited more severe and more progressive degenerative alterations than mdx TA muscles. Taken together, these observations indicated that newly formed myotubes showed markedly increased expression of miR-206, which might reflect active regeneration and efficient maturation of skeletal muscle fibers. 相似文献
92.
Kinoshita M Kobayashi N Nagashima S Ishino M Otokozawa S Mise K Sumi A Tsutsumi H Uehara N Watanabe N Endo M 《Microbiology and immunology》2008,52(7):334-348
Staphylocoagulase (SC) is a major phenotypic determinant of Staphylococcus aureus. Serotype of SC (coagulase type) is used as an epidemiological marker and 10 types (I-X) have been discriminated so far. To clarify genetic diversity of SC within a single and among different serotype(s), we determined approximately 1500 bp-nucleotide sequences of SC gene encoding D1, D2, and central regions (N-terminal half and central regions of SC; SC(NC)) for a total of 33 S. aureus strains comprising two to three strains from individual coagulase types (I-VIII, X) and 10 strains which were not determined as previously known SC serotypes (ND-strains). Amino acid sequence identities of SC(NC) among strains with a single coagulase type of II, III, IV, V, VI and X were extremely high (more than 99%), whereas lower identity (56-87%) was observed among different types. In contrast, within a single coagulase type of I, VII, or VIII, sequence divergence was found (lowest identity; 82%). SC(NC) sequences from the ND-strains were discriminated into two genetic groups with an identity of 71% to each other (tentatively assigned to genotypes [XI] and [XII]), and exhibited less than 86% sequence identities to those of most known coagulase types. All the types [XI] and [XII] strains were methicillin susceptible and belonged to different sequence types from those of coagulase types I-X strains reported so far by multilocus sequence typing. These findings indicated genetic heterogeneity of SC in coagulase types I, VII, and VIII strains, and the presence of two novel SC genotypes related to antigenicity of SC serotypes. 相似文献
93.
Ying Xiong Chaitanya Raj Adhikari Hidetaka Kawakita Keisuke Ohto Katsutoshi Inoue Hiroyuki Harada 《Bioresource technology》2009,100(18):4083-4089
Persimmon waste was chemically modified with dimethylamine (DMA) to obtain a tertiary-amine-type gel, named DMA persimmon waste gel (DMA-PW). It was found to be effective for the adsorption of Au(III), Pd(II), and Pt(IV) in hydrochloric acid medium. In contrast, base metals such as Cu(II), Zn(II), Fe(III), and Ni(II) were not practically adsorbed. The formation of ion pairs of the metal chloro complex anions with the protonated adsorption gels was proposed as the main adsorption process. The gel exhibited selectivity only for precious metals with a remarkably high capacity for Au(III), i.e., 5.63 mol/kg dry gel and comparable capacities, i.e., 0.42 and 0.28 mol/kg for Pd(II) and Pt(IV), respectively. According to the kinetic and electrochemical studies, the adsorption rate of Au(III) was greatly enhanced by the chemical modification. Also, its excellent adsorption characteristics for the precious metals were confirmed by adsorption and elution tests using a column packed with the DMA-PW gel. 相似文献
94.
Artificial cross between two genetically different populations of Japanese Misgurnus loach was made to examine the reproductive capacity of the artificial inter-populational hybrid females. Ploidy status and
microsatellite genotypes of the eggs laid by these hybrids were inferred from those determined in progenies developed by normal
fertilization with haploid loach sperm, induced gynogenesis with UV-irradiated goldfish sperm and/or hybridization with intact
goldfish sperm. Some hybrid females laid unreduced diploid eggs genetically identical to the mother. However, these diploid
eggs could not develop by spontaneous gynogenesis, but grow to triploid by incorporation of a sperm nucleus. Other hybrid
females laid haploid eggs together with diploid eggs and/or various aneuploid and polyploid eggs. Thus, a disruption of normal
meiosis occurred in inter-populational hybrid females. The results suggested that the two populations should be so distant
as to give rise to atypical formation of unreduced and other unusual eggs in their hybrids. 相似文献
95.
Kazuhiko Mochida Katsutoshi Ito Hiroya Harino Hiroyuki Tanaka Toshimitsu Onduka Akira Kakuno Kazunori Fujii 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2009,149(4):624-630
In a previous study, we demonstrated that exposure to an antifouling biocide, copper pyrithione (CuPT), early during life induced vertebral deformity in the larvae of a marine fish, the mummichog (Fundulus heteroclitus). Skeletal deformities may be caused by inhibition by of acetylcholiensterase (AChE) activity, and to elucidate the mechanism underlying the CuPT-associated vertebral deformity, we first examined whether CuPT, zinc pyrithione (ZnPT), and their degradation products could inhibit AChE activity in the fish. Two of the degradation products, 2,2′-dipyridyldisulfide [(PS)2] and 2,2′-dithiobispyridine-N-oxide [(PT)2], but neither CuPT nor ZnPT, exhibited prominent AChE-inhibiting activity. Secondly, thin-layer chromatography revealed that mummichog hepatic microsomes metabolized CuPT to produce (PS)2 in a microsome-dependent manner. The AChE inhibition induced in CuPT-exposed fish is likely due to (PS)2 that was produced through metabolism of acquired CuPT. (PS)2 may cause therefore skeletal deformity in CuPT-exposed fish by means of its neuromuscular blocking properties, through a mechanism similar to that proposed for animals exposed to organophosphorous pesticides. 相似文献
96.
Twelve dinucleotide markers were successfully isolated and characterized from a microsatellite‐enriched genomic library obtained for the gudgeon Squalidus chankaensis biwae. These markers were also available for the congeners S. c. tsuchigae and S. japonicus from Japan, which had five to 46 alleles and an expected heterozygosity ranging from zero to 0.946. Linkage equilibrium was observed at all loci, and most loci did not show significant deviation from Hardy–Weinberg equilibrium. The isolated microsatellite markers will be useful for genetic diversity studies of Squalidus populations. 相似文献
97.
Ya-Juan Li Yi Tian Ming-Zhao Zhang Ping-Ping Tian Zhuo Yu Syuiti Abe Katsutoshi Arai 《Ichthyological Research》2010,57(4):358-366
The chromosomes of the diploid and tetraploid loach Misgurnus anguillicaudatus were analyzed by staining with Ag, chromomycin A3 (CMA3)/distamycin A (DA), and DA/4′,6-diamidino-2-phenylindole (DAPI), and using fluorescence in situ hybridization (FISH) with
5.8S + 28S rDNA as a probe. Nucleolus organizer regions (NORs) were mapped to the telomeric region of the short arms of the
largest (first) metacentric chromosome pair in the diploid loach with 2n = 50 and the homologous quartet in the tetraploid loach with 4n = 100. The NORs were positive at the same region of the first metacentric chromosome for Ag and CMA3/DA stainings, but negative for DA/DAPI staining. Four signals at the homologs within the same quartet suggest the duplication
of the entire genome from diploid to tetraploid status. However, a size difference was detected between the rDNA signals by
FISH and CMA3 banding. 相似文献
98.
Byoung-In Sang Won-Kwon Lee Katsutoshi Hori Hajime Unno 《World journal of microbiology & biotechnology》2006,22(1):51-57
Summary Poly(3-hydroxybutyrate) [P(3HB)] depolymerase was purified from a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)]-degrading fungus, Paecilomyces lilacinus F4-5 by hydrophobic and ion exchange column chromatography, and showed a molecular mass of 45 kDa. The optimum temperature
and pH of the P(3HB) depolymerase were 50 °C and 7.0, respectively. The enzyme was stable for at least 30 min at temperatures
below 40 °C, while the activity abruptly decreased over 55 °C. Enzymatic P(3HB-co-3HV) degradation showed a similar degradation pattern to that of film overlaid by fungal hyphae. It reflects that the fungal
degradation of P(3HB-co-3HV) in soil is mainly caused by extracellular depolymerases. 相似文献
99.
Matsuda H Yoshida K Miyagawa K Nemoto Y Asao Y Yoshikawa M 《Bioorganic & medicinal chemistry letters》2006,16(6):1567-1573
The methanolic extract and its alkaloid fraction from the rhizomes of Nuphar pumilum showed cytotoxic effects on human leukemia cell (U937), mouse melanoma cell (B16F10), and human fibroblast (HT1080). Dimeric sesquiterpene thioalkaloids with the 6-hydroxyl group (6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B) showed substantial cytotoxic activity at a concentration of 10 microM, but dimeric sesquiterpene thioalkaloids lacking the 6-hydroxyl group (thiobinupharidine, thionuphlutine B, 6'-hydroxythionuphlutine B, neothiobinupharidine, thionuphlutine B beta-sulfoxide, and neothiobinupharidine beta-sulfoxide) and monomeric sesquiterpene alkaloids (nupharidine, 7-epideoxynupharidine, and nupharolutine) showed weak activity. Next, apoptosis-inducing activity of a principal active constituent, 6-hydroxythiobinupharidine, on U937 was examined using morphological observation and DNA fragmentation assay (TUNEL method). Apoptosis of U937 was immediately observed within 1 h after treatment of 6-hydroxythiobinupharidine at 2.5-10 microM. 相似文献
100.
Production of Transgenic-clone Pigs by the Combination of ICSI-mediated Gene Transfer with Somatic Cell Nuclear Transfer 总被引:5,自引:0,他引:5
The objective of this study was to examine whether the ICSI-mediated gene transfer method using in vitro matured oocytes and frozen sperm head could actually produce transgenic pigs. We also aimed at examining whether transgenic
pigs can be cloned from somatic cells of a transgenic pig generated by the ICSI-mediated method. A bicistronic gene constituted
of the human albumin (hALB) and enhanced green fluorescent protein (EGFP) genes was introduced into pig oocytes by the ICSI-mediated
method. Transfer of 702 embryos produced by the ICSI-mediated method into five gilts resulted in 4 pregnancies. When three
of the recipients, which had received total 312 of the embryos were autopsied, 32 including 1 transgenic fetuses were obtained.
One of the recipients gave birth to three live piglets including one transgenic pig, showing a strong green fluorescence in
the eyeballs, oral mucous membrane and subcutaneous tissues. Fluorescent microscopy revealed uniform GFP expression in all
cell lines established from kidney, lung and muscle of the founder transgenic pig obtained. Nuclear transfer of these cells
resulted in stable in vitro development of cloned embryos into the blastocyst stage, ranging from 12.9 to 19.8%. When 767 of the nuclear transfer embryos
were transferred to 5 recipients, all became pregnant and gave birth to a total of six live transgenic-clones. The transgene
copy number and integrity in the founder pig were maintained in the primary culture cells established from the founder as
well as in the clones produced from these cells. Our study demonstrates that the ICSI-mediated gene transfer is an efficient
and practical method to produce transgenic pigs, using frozen sperm heads and in vitro matured oocytes. It was also shown that combination of ICSI-mediated transgenesis and nuclear transfer is a feasible technology
of great potential in transgenic pig production. 相似文献