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941.
Regenerating adult chicken skeletal muscle and satellite cell cultures express embryonic patterns of myosin and tropomyosin isoforms 总被引:11,自引:0,他引:11
Regenerating areas of adult chicken fast muscle (pectoralis major) and slow muscle (anterior latissimus dorsi) were examined in order to determine synthesis patterns of myosin light chains, heavy chains and tropomyosin. In addition, these patterns were also examined in muscle cultures derived from satellite cells of adult fast and slow muscle. One week after cold-injury the regenerating fast muscle showed a pattern of synthesis that was predominately embryonic. These muscles synthesized the embryonic myosin heavy chain, beta-tropomyosin and reduced amounts of myosin fast light chain-3 which are characteristic of embryonic fast muscle but synthesized very little myosin slow light chains. The regenerating slow muscle, however, showed a nearly complete array of embryonic peptides including embryonic myosin heavy chain, fast and slow myosin light chains and both alpha-fast and slow tropomyosins. Peptide map analysis of the embryonic myosin heavy chains synthesized by regenerating fast and slow muscles showed them to be identical. Thus, in both muscles there is a return to embryonic patterns during regeneration but this return appears to be incomplete in the pectoralis major. By 4 weeks postinjury both regenerating fast and slow muscles had stopped synthesizing embryonic isoforms of myosin and tropomyosin and had returned to a normal adult pattern of synthesis. Adult fast and slow muscles yielded a satellite cell population that formed muscle fibers in culture. Fibers derived from either population synthesized the embryonic myosin heavy chain in addition to alpha-fast and beta-tropomyosin. Thus, muscle fibers derived in culture from satellite cells of fast and slow muscles synthesized a predominately embryonic pattern of myosin heavy chains and tropomyosin. In addition, however, the satellite cell-derived myotubes from fast muscle synthesized only fast myosin light chains while the myotubes derived from slow muscle satellite cells synthesized both fast and slow myosin light chains. Thus, while both kinds of satellite cells produced embryonic type myotubes in culture the overall patterns were not identical. Satellite cells of fast and slow muscle appear therefore to have diverged from each other in their commitment during maturation in vivo. 相似文献
942.
Mohd A. Hassan Mohammed A. Ahmad Farid Yoshihito Shirai Hidayah Ariffin Mohd R. Othman Mohd H. Samsudin Mohamad Y. Hasan 《Biotechnology journal》2019,14(6)
Oil palm biomass is widely known for its potential as a renewable resource for various value‐added products due to its lignocellulosic content and availability. Oil palm biomass biorefinery is an industry that comes with sociopolitical benefits through job opportunities, as well as potential environmental benefits. Many studies have been conducted on the technological advancements of oil‐palm biomass‐derived renewable materials, which are discussed comprehensively in this review. Recent technological developments have made it possible to bring new and innovative technologies to commercialization, such as compost, biocharcoal, biocomposites, and bioplastics. 相似文献
943.
Ryoichi Nakajima Tadayuki Imanaka Shuichi Aiba 《Applied microbiology and biotechnology》1986,23(5):355-360
Summary A comparison was made of the amino acid sequences of 11 different -amylases. The 6 animal -amylases tested were found to be highly homologous (about 80 to 90%, depending on the species compared). Amino acid sequence of Bacillus stearothermophilus -amylase was fairly homologous (about 60%) with that of a thermostable -amylase from Bacillus amyloliquefaciens. Homology was least among the thermolabile amylases from Bacillus subtilis, Aspergillus oryzae, plants and animals. Nevertheless, four highly homologous regions were found in the amino acid sequences of all the enzymes, despite their widely different origins. It was inferred that these four homologous regions were likely to be the active and/or substrate-binding sites. 相似文献
944.
The analysis of fatty acid composition of plasma and tissue is important as a method for studying lipid nutrition. We investigated the possibility of direct methylation of fatty acids by BF(3)-methanol from plasma and from liver and brain homogenates without lipid extraction. There were no ghost peaks in the chromatogram produced by the direct methylation method. The 18:0 percentages were significantly higher in the direct methylation method than in the lipid extraction method. There were not remarkable differences in fatty acid composition in the direct methylation and methylation after lyophilization methods. Furthermore, the recovery ratio of the internal standard in the direct methylation method was higher than that in the lipid extraction method. The difference of fatty acid composition with lipid extraction may be caused by the change of lipid class extraction. Therefore, the direct methylation method without lipid extraction is the most suitable for determining fatty acid composition in plasma and tissue. 相似文献
945.
Preparation for flight: pre‐fledging exercise time is correlated with growth and fledging age in burrow‐nesting seabirds 下载免费PDF全文
Ken Yoda Tatsuya Shiozaki Masaki Shirai Sakiko Matsumoto Maki Yamamoto 《Journal of avian biology》2017,48(6):881-886
Chicks of many burrow‐nesting seabirds are known to repeatedly emerge from their nests (these trips being termed ‘excursions’) and exercise their wings prior to fledging, but this behavior is poorly documented in the literature, and thus the relationship between growth and exercise remains unclear. Here, we used infrared video cameras placed in front of streaked shearwater Calonectris leucomelas nests during the chick‐emergence period to examine correlations between chick excursions and parameters known to be important for juvenile survival after fledging. In addition, we also attached acceleration‐temperature loggers to several chicks in order to evaluate the relationship between excursion time and time spent exercising the wing muscles (i.e. flapping). Chicks that undertook longer excursions exhibited more rapid increases in wing length and larger body masses at fledging, and also fledged earlier. Correlations between fitness‐related parameters and excursion time indicate that excursions during the emergence period might offer insights into the various relationships between growth and behavior and/or the mechanisms underlying offspring survival following fledging. 相似文献
946.
p38 Mitogen-Activated Protein Kinase Functionally Contributes to Chondrogenesis Induced by Growth/Differentiation Factor-5 in ATDC5 Cells 总被引:15,自引:0,他引:15
Koji Nakamura Takuhiro Shirai Setsuo Morishita Sanae Uchida Kazuko Saeki-Miura Fusao Makishima 《Experimental cell research》1999,250(2):351-363
Recent studies of intracellular signal transduction mechanisms for the transforming growth factor-beta (TGF-beta) superfamily have focused on Smad proteins, but have paid little attention to mitogen-activated protein (MAP) kinase cascades. Here we demonstrate that growth/differentiation factor-5 (GDF-5), but neither bone morphogenetic protein-2 (BMP-2) nor TGF-beta1, fully promotes the early phase of the chondrogenic response by inducing cellular condensation followed by cartilage nodule formation in a mouse chondrogenic cell line, ATDC5. We investigated which, if any, of the three major types of MAP kinase plays a functional role in the promotion of chondrogenesis induced by GDF-5. GDF-5 induced phosphorylation of p38 MAP kinase and extracellular signal-regulated kinase (ERK) but not that of c-Jun N-terminal kinase (JNK). The phosphorylation of p38 MAP kinase was also induced by BMP-2 and TGF-beta1. An inhibitor of p38 and p38 beta MAP kinase, SB202190, showed complete inhibition of cartilage nodule formation but failed to affect alkaline phosphatase (ALP) activity induced by GDF-5. Expression of the type II collagen gene, a hallmark of chondrogenesis in vertebrates, was also induced by GDF-5 treatment and strongly suppressed by SB202190. On the other hand, although an inhibitor of MAP/ERK kinase, PD98059, inhibited the rapid phosphorylation of ERK by GDF-5, it inhibited neither ALP activity nor cartilage nodule formation induced by GDF-5. These results strongly suggest that the p38 MAP kinase cascade is involved in GDF-5 signaling pathways and that a role of the p38 MAP kinase pathway is necessary over a longer period to promote chondrogenesis in ATDC5 cells. 相似文献
947.
Phylogeny and historical demography of endemic fishes in Lake Biwa: the ancient lake as a promoter of evolution and diversification of freshwater fishes in western Japan 下载免费PDF全文
Ryoichi Tabata Ryo Kakioka Koji Tominaga Takefumi Komiya Katsutoshi Watanabe 《Ecology and evolution》2016,6(8):2601-2623
To elucidate the origins of the endemic fish of Lake Biwa, an ancient lake in Japan, and the role of the lake in the diversification of freshwater fish in western Japan, we established a molecular phylogenetic framework with an absolute time scale and inferred the historical demography of a large set of fish species in and around the lake. We used mtDNA sequences obtained from a total of 190 specimens, including 11 endemic species of Lake Biwa and their related species, for phylogenetic analyses with divergence time estimations and from a total of 2319 specimens of 42 species (including 14 endemics) occurring in the lake for population genetic analyses. Phylogenetic analysis suggested that some of the endemic species diverged from their closest relatives earlier (1.3–13.0 Ma) than the period in which the present environmental characteristics of the lake started to develop (ca. 0.4 Ma), whereas others diverged more recently (after 0.4 Ma). In contrast, historical demographic parameters suggested that almost all species, including endemic and nonendemic ones, expanded their populations after the development of the present lake environment. In phylogeographic analyses, common or very close haplotypes of some species were obtained from Lake Biwa and other regions of western Japan. The phylogenetic and historical demographic evidence suggests that there was a time lag between phylogenetic divergence and population establishment and that phenotypic adaptation of some endemic species to the limnetic environment occurred much later than the divergences of those endemic lineages. Population structure and phylogeographic patterns suggest that Lake Biwa has functioned not only as the center of adaptive evolution but also as a reservoir for fish diversity in western Japan. 相似文献
948.
949.
950.
Haruki Momma Kaijun Niu Yoritoshi Kobayashi Cong Huang Atsushi Otomo Masahiko Chujo Hiroko Tadaura Ryoichi Nagatomi 《PloS one》2014,9(4)