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91.
Hanamura S Kiyono M Lukasik-Braum M Mlengeya T Fujimoto M Nakamura M Nishida T 《Primates; journal of primatology》2008,49(1):77-80
A flu-like disease spread among chimpanzees (Pan troglodytes schweinfurthii) of the M group at Mahale Mountains National Park, Tanzania, from June to July 2006. This epizootic or epidemic killed up
to 12 chimpanzees. The obvious evidence of their deaths came from finding the bodies of three infants who had previously shown
some symptoms of the disease. At least one of these infants died of pneumonia. In addition, nine chimpanzees were missing
after the outbreak. These individuals were assumed to have been killed by this epizootic because most of them had contact
with the infected individuals on the last days they were observed. We also found two dead bodies during this period, which
were thought to be those of two missing individuals. We confirmed 23 (35.4%) of 65 individuals of the M group showed some
symptoms of the disease, although most of them (20/23) did not die. More than half of them (14/23) had kin showing symptoms.
Since this epizootic may have been caused by contact with humans, it will be necessary to establish and follow appropriate
protocols for researchers, tourists, and park staff to observe chimpanzees, and to explore the mechanism of disease transmission
from humans to chimpanzees and among chimpanzees. 相似文献
92.
Hanya G Matsubara M Hayaishi S Zamma K Yoshihiro S Kanaoka MM Sugaya S Kiyono M Nagai M Tsuriya Y Hayakawa S Suzuki M Yokota T Kondo D Takahata Y 《Primates; journal of primatology》2008,49(2):116-125
Feeding conditions, competitive regime, and female social relationships of Japanese macaques (Macaca fuscata) on Yakushima were compared between the two habitats at two different altitudes (coniferous forest, 1,000–1,200 m and coastal
forest, 0–200 m). Fruit availability was higher in the coastal forest. There was no consistent difference in the frequency
of agonistic interactions within a group during feeding between the two habitats. The coastal forest evoked stronger inter-group
contest competition compared to the coniferous forest as evidenced by a higher inter-group encounter rate and a higher proportion
of aggressive encounters to non-aggressive ones. Birth rate was higher in larger groups compared to smaller ones in the coastal
forest, but did not differ in the coniferous forest. In spite of these differences in competitive regime, no variation in
female social relationships was observed, such as direction and concentration on particular individuals in grooming, linearity
in dominance rank, counter-attack, and support of juvenile kin during agonistic interactions. The present results indicate
that the female social relationships of Japanese macaques are robust and do not change according to changes in the current
environment. 相似文献
93.
Chiaki Ogino Shunichi Kuroda Shinji Tokuyama Akihiko Kondo Nobuaki Shimizu Katsuyuki Tanizawa Hideki Fukuda 《Journal of Molecular Catalysis .B, Enzymatic》2003,23(2-6):107-115
This review is focusing on an industrially important enzyme, phospholipase D (PLD), exhibiting both transphosphatidylation and hydrolytic activities for various phospholipids. The transphosphatidylation activity of PLD is particularly useful for converting phosphatidylcholine (PC) into other phospholipids. During the last decade, the genes coding for PLD have been identified from various species including mammals, plants, yeast, and bacteria. However, detailed basic and applied enzymological studies on PLD have been hampered by the low productivity in these organisms. Efficient production of a recombinant PLD has also been unsuccessful so far. We recently isolated and characterized the PLD gene from Streptoverticillium cinnamoneum, producing a secretory PLD. Furthermore, we constructed an overexpression system for the secretory enzyme in an active and soluble form using Streptomyces lividans as a host for transformation of the PLD gene. The Stv. cinnamoneum PLD was proven to be useful for the continuous and efficient production of phosphatidylethanolamine (PE) from phosphatidylcholine. Thus, the secretory PLD is a promising catalyst for synthesizing new phospholipids possessing various polar head groups that show versatile physiological functions and may be utilized in food and pharmaceutical industries. 相似文献
94.
LST‐03 lipase from an organic solvent‐tolerant Pseudomonas aeruginosa LST‐03 has high stability and activity in the presence of various organic solvents. In this research, enhancement of organic solvent‐stability of LST‐03 lipase was attempted by directed evolution. The structural gene of the LST‐03 lipase was amplified by the error prone‐PCR method. Organic solvent‐stability of the mutated lipases was assayed by formation of a clear zone of agar which contained dimethyl sulfoxide (DMSO) and tri‐n‐butyrin and which overlaid a plate medium. And the organic solvent‐stability was also confirmed by measuring the half‐life of activity in the presence of DMSO. Four mutated enzymes were selected on the basis of their high organic solvent‐stability in the presence of DMSO. The organic solvent‐stabilities of mutated LST‐03 lipase in the presence of various organic solvents were measured and their mutated amino acid residues were identified. The half‐lives of the LST‐03‐R65 lipase in the presence of cyclohexane and n‐decane were about 9 to 11‐fold longer than those of the wild‐type lipase, respectively. Some substituted amino acid residues of mutated LST‐03 lipases have been located at the surface of the enzyme molecules, while some other amino acid residues have been changed from neutral to basic residues. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
95.
Ken Horii Takashi Adachi Tetsuya Matsuda Tsutomu Tanaka Hiroshi Sahara Seiji Shibasaki Chiaki Ogino Yoji Hata Mitsuyoshi Ueda Akihiko Kondo 《Journal of Molecular Catalysis .B, Enzymatic》2009,59(4):297-301
β-Glucosidase (BGL1) from Aspergillus oryzae was efficiently produced in recombinant A. oryzae using sodM promoter-mediated expression system. The yield of BGL1 was 960 mg/l in liquid culture, which is 20-fold higher than the yield of BGL1 produced using the yeast Saccharomyces cerevisiae. Recombinant BGL1 converted isoflavone glycosides into isoflavone aglycones more efficiently than β-glucosidase from almond. In addition, BGL1 produced isoflavone aglycones even in the presence of the insoluble form of isoflavone glycosides. 相似文献
96.
Nao Odajima Tomoko Betsuyaku Katsura Nagai Chinatsu Moriyama Da-Hong Wang Tomoko Takigawa Keiki Ogino Masaharu Nishimura 《Respiratory research》2010,11(1):183
Background
Catalase is preferentially expressed in bronchiolar and alveolar epithelial cells, and acts as an endogenous antioxidant enzyme in normal lungs. We thus postulated epithelial damage would be associated with a functional deficiency of catalase during the development of lung fibrosis.Methods
The present study evaluates the expression of catalase mRNA and protein in human interstitial pneumonias and in mouse bleomycin-induced lung injury. We examined the degree of bleomycin-induced inflammation and fibrosis in the mice with lowered catalase activity.Results
In humans, catalase was decreased at the levels of activity, protein content and mRNA expression in fibrotic lungs (n = 12) compared to control lungs (n = 10). Immunohistochemistry revealed a decrease in catalase in bronchiolar epithelium and abnormal re-epithelialization in fibrotic areas. In C57BL/6J mice, catalase activity was suppressed along with downregulation of catalase mRNA in whole lung homogenates after bleomycin administration. In acatalasemic mice, neutrophilic inflammation was prolonged until 14 days, and there was a higher degree of lung fibrosis in association with a higher level of transforming growth factor-β expression and total collagen content following bleomycin treatment compared to wild-type mice.Conclusions
Taken together, these findings demonstrate diminished catalase expression and activity in human pulmonary fibrosis and suggest the protective role of catalase against bleomycin-induced inflammation and subsequent fibrosis. 相似文献97.
Azuma H Miyasaka K Yokotani T Tachibana T Kojima-Yuasa A Matsui-Yuasa I Ogino K 《Bioorganic & medicinal chemistry》2006,14(6):1811-1818
Structure-activity relationships of 1'-acetoxychavicol acetate (ACA) for apoptotic activity against human leukemia HL-60 cells were investigated using optically active ACA and various racemic ACA analogues. Natural-type (or with different acyl group) ACA showed a high apoptotic activity, but the ortho or meta isomers, 4-deacetoxy analogue, and the 2'-3' dehydrogenated derivative had no effect, or a weak activity. Optically active (R)- and (S)-ACA were prepared by a lipase-catalyzed esterification. Using a mixture of vinyl acetate-tetrahydrofuran (1:1 v/v) as a solvent at refluxing temperature, optically pure (R)- and (S)-ACA were obtained (99.7% ee and 99.1% ee, respectively). The apoptosis-inducing effects of both enantiomers were compared by means of an MTT assay and the detection of typical apoptotic phenomena (DNA fragmentation, caspase-3 activation, and PARP cleavage) and these two activities were almost equal. These results indicate that the essential moieties of ACA for apoptotic activity against HL-60 cells are both the presence of a 4-acetoxyl group and an unsaturated double bond between C-2' and C-3', and that the configuration at the 1'-position is unrelated to activity. 相似文献
98.
The dependency on depleting natural resources is a challenge for energy security that can be potentially answered by bioenergy. Bioenergy is derived from starchy and lignocellulosic biomass in the form of bioethanol or from vegetable oils in the form of biodiesel fuel. The acid and enzymatic methods have been developed for the hydrolysis of biomass and for transesterifiaction of plant oils. However, acid hydrolysis results in the production of unnatural compounds which has adverse effects on yeast fermentation. Recent advancements in the yeast cell surface engineering developed strategies to genetically immobilize amylolytic, cellulolytic and xylanolytic enzymes on yeast cell surface for the production of fuel ethanol from biomass. This review gives an insight in to the recent technological developments in the production of bioenergy, i.e, bioethanol using surface engineered yeast. 相似文献
99.
Hanya G Ménard N Qarro M Ibn Tattou M Fuse M Vallet D Yamada A Go M Takafumi H Tsujino R Agetsuma N Wada K 《Primates; journal of primatology》2011,52(2):187-198
Habitat, diet and leaf chemistry are compared between Japanese and Barbary macaques to reveal the similarities and differences in dietary adaptations of temperate primates living at the eastern and western extremes of the genus Macaca. Tree species diversity and proportion of fleshy-fruited species are much higher in Japan than in North Africa. Both species spend considerable annual feeding time on leaves. Japanese macaques prefer fruits and seeds over leaves, and Barbary macaques prefer seeds. These characteristics are adaptive in temperate regions where fruit availability varies considerably with season, since animals can survive during the lean period by relying on leaf and other vegetative foods. The two species are different with respect to the higher consumption of herbs by Barbary macaques, and the leaves consumed contain high condensed and hydrolysable tannin for Barbary but not for Japanese macaques. Barbary macaques supplement less diverse tree foods with herbs. Because of the low species diversity and high tannin content of the dominant tree species, Barbary macaques may have developed the capacity to cope with tannin. This supports the idea that digestion of leaves is indispensable to survive in temperate regions where fruit and seed foods are not available for a prolonged period during each year. 相似文献
100.
Yasuda M Kunieda H Ono K Ogino H Iwasaki T Hiramoto M Glomm WR Hirabayashi Y Aizawa S 《Tissue & cell》2011,43(2):115-124
In this study, we synthesized a new cell immobilization support having poly(glycidyl methacrylate) as a graft polymer chain and used this support for cell cultivation. Base polymer particle was synthesized by suspension polymerization and epoxy polymer chain was extended from particle surface on graft polymerization. Produced polymer particles had broad particle size distribution ranging from 20 to 1000 μm and the degree of polymerization of grafted polymer chain was ranged from 500 to 1000. The effects of various factors, such as grafted polymer chain length and its surface density, composition of base polymer network and graft polymer chain, on the cell growth of murine fibroblast cell line (MS-5 cell) on polymer particle were studied. This polymer particle could cultivate not only fibroblast cell line but also epidermal cell line (HeLa cell), osteoblast cell line (MC3T3E1 cell), and chondrocyte cell line (ch-8 cell) on its surface. Growth rate is almost the same as that of cells using poly(styrene) tissue culture dish. To apply this cell cultivation system for examination of cell co-culture, HeLa cell immobilized on 100 μm of polymer particle was successfully co-cultured with MS-5 cell immobilized on 300 μm of polymer particle for four weeks. 相似文献