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141.
142.
Tatsunobu Matsui Yukie Yamada Hideki Mitsuya Yasushi Shigeri Yasukazu Yoshida Yoshiro Saito Hiroshi Matsui Kunihiko Watanabe 《Applied microbiology and biotechnology》2009,82(5):941-950
The sustainable and practical degradation of intact chicken feathers by a newly isolated thermophilic bacterium Meiothermus ruber H328 was presented with extensive data. Aerobic cultivation with moderately thermophilic strain H328 at 55°C for 6 days led
to the apparently complete decay of the truly intact feathers and provided 1.89 mmol free amino acids and 7.32 mmol acid-hydrolyzed
amino acids from 50 ml of culture containing 3% (w/v) intact chicken feathers. The amino acid components in the soluble fraction of the culture conspicuously agreed with those
calculated from the intact feathers. This demonstrated that more than 55% of total keratin proteins were solubilized from
the intact chicken feathers into the culture in the forms of free amino acid and/or soluble oligopeptide, and most of them
are directly derived from the intact feathers by proteolytic digestion. Feather degradation by strain H328 surpasses that
by any other microorganisms with regard to degradation efficiency, absence of requirement for pretreatment of the feathers,
and product fidelity in the amino acid component. Furthermore, the culture containing the degradative products from the intact
feathers was subjected to matrix-assisted laser desorption ionization mass spectrometry-time-of-flight analysis, and it was
revealed that the molecular masses of the solubilized products, oligopeptides, were less than 1,000. This result allows us
to investigate the bioactivities of oligopeptides derived from the degradation of chicken feathers by cultivation with strain
H328 as well as the production of amino acids for feedstuffs. 相似文献
143.
Long-term cryopreservation of mouse sperm 总被引:2,自引:0,他引:2
The objective was to determine if mouse sperm can maintain their fertilizing ability after being frozen for >10 y and whether the offspring derived from these sperm had normal fertilizing ability and phenotype. We cryopreserved sperm from six strains of mice (C57BL/6J, DBA/2N, BALB/cA, C3H/HeJ, B6D2F1 and B6C3F1) in a solution containing 18% (w/v) raffinose and 3% (w/v) skim milk, and preserved them in liquid nitrogen for >10 y. To assess the normality and fertilizing ability of these sperms, they were thawed and used for in vitro fertilization of oocytes of the same strains. Fertilization rates for C57BL/6J, DBA/2N, BALB/cA, C3H/HeJ, B6D2F1 and B6C3F1 were 66.4, 92.3, 72.8, 32.9, 60.3 and 53.7%, respectively. Furthermore, 38.3, 15.0, 43.3, 26.1, 38.3 and 16.7% of the embryos transferred to pseudopregnant females developed and produced live offspring that had normal phenotype and fertility. 相似文献
144.
Since insects are unable to biosynthesize sterols de novo, sterols must be obtained from dietary sources. Although it has been reported that beta-sitosterol is crucial for larval growth in the silkworm, Bombyx mori, little has been investigated concerning the dietary selection of sterols by Bombyx larvae. Here, we demonstrate that Bombyx larvae have the following sterol preference: beta-sitosterol > ergosterol > cholesterol = stigmasterol. Interestingly, Bombyx larvae preferred ergosterol, an inhibitory sterol on larval growth, indicating that sterol selection following first contact of the diet with the mouth part might be different from the sterol recognition mechanism present in sterol metabolism. 相似文献
145.
Toru Takeo Yukie Haruguchi Hiromi Machida Yoshiko Nakagawa Toyokazu Matsuguma Norihiko Shimizu Motohito Goto Masayuki Anzai Koji Nomaru 《Cryobiology》2009,58(2):196-202
Cryopreservation of 2-cell embryos is an effective technology for storage of genetically engineered mouse strains. Transport of genetically engineered mice between laboratories has frequently been performed using such cryopreserved 2-cell embryos. However, the receiving laboratory requires proficient skills and special instruments to obtain live young from cryopreserved and transported embryos. Therefore, in this study, we tried to address the storage and transport of vitrified/warmed 2-cell embryos at a cold temperature. In cold storage experiments, the development rates of 2-cell embryos stored in M2 medium for 24, 48 and 72 h into blastocysts were relatively high (83%, 63% and 43%, respectively). Although, 2-cell embryos stored in PB1 and mWM maintained the developmental potency for 24 h, the rates were markedly decreased to low levels after 48 h (PB1: 0%; mWM: 5%). In transport experiments, many pups were obtained from vitrified/warmed 2-cell embryos transported at a cold temperature in all receiving laboratories (incidence of successful development: 49%; 249/511). In summary, short-term storage and transport of vitrified/warmed 2-cell embryos in M2 medium at a cold temperature can maintain their ability to develop into live young. 相似文献
146.
Mitsuru Tsuge Kozo Yasui Takashi Ichiyawa Yukie Saito Yoshiharu Nagaoka Masato Yashiro Nobuko Yamashita Tsuneo Morishima 《Microbiology and immunology》2010,54(7):417-424
Increases of cytokine in the blood play important roles in the pathogenesis of influenza‐associated encephalopathy. TNF‐α was administered intravenously to wild‐type mice, after which blood, CSF and brain tissue were obtained, and changes in BBB permeability, the amounts of MMP‐9 and TIMP‐1, and the localization of activated MMP were assessed. There was a significant increase in BBB permeability after 6 and 12 hr. MMP‐9 was increased after 3 hr in the brain and cerebrospinal fluid, which was earlier than in the serum. TIMP‐1 protein in the brain increased significantly after MMP‐9 had increased. Activation of MMP‐9 was observed in neurons in the cerebral cortex and hippocampus, and in vascular endothelial cells. These findings suggest that an increase in blood TNF‐α promotes activation of MMP‐9 in the brain, and may also induce an increase in permeability of the BBB. Early activation of MMP‐9 in the brain may contribute to an early onset of neurological disorders and brain edema prior to multiple organ failure in those inflammatory diseases associated with highly increased concentrations of TNF‐α in the blood, such as sepsis, burns, trauma and influenza‐associated encephalopathy. 相似文献
147.
Sexual size dimorphism (SSD) is a common phenomenon in animals. In many species females are substantially larger than males.
Because body size plays a central role in modulating the body temperature (T
b) of ectotherms, intersexual differences in body size may lead to important intersexual differences in thermoregulation. In
addition, because SSD is realized by differences in growth rate and because growth rate is strongly temperature dependent
in ectotherms, a conflict between male reproductive behaviour and thermoregulation may affect the expression of SSD. In this
study, we investigated the thermal implications of SSD in a reptile exhibiting spectacular female-biased SSD: the northern
map turtle (Graptemys geographica). Over three seasons, we collected >150,000 measurements of T
b in free-ranging adult and juvenile northern map turtles using surgically implanted miniature temperature loggers. Northern
map turtles exhibited seasonal patterns of thermoregulation typical of reptiles in northern latitudes, but we found that large
adult females experienced a lower daily maximum T
b and a narrower daily range of T
b than adult males and small juvenile females. In addition, despite more time spent basking, large adult females were not able
to thermoregulate as accurately as small turtles. Our findings strongly suggest that body size limits the ability to thermoregulate
accurately in large females. By comparing thermoregulatory patterns between adult males and juvenile females of similar body
size, we found no evidence that male reproductive behaviours are an impediment to thermoregulation. We also quantified the
thermal significance of basking behaviour. We found, contrary to previous findings, that aerial basking allows northern map
turtles to raise their T
b substantially above water temperature, indicating that basking behaviour likely plays an important role in thermoregulation. 相似文献
148.
Eguchi M Sekiya Y Kikuchi Y Takaya A Yamamoto T Matsui H 《FEMS immunology and medical microbiology》2007,50(3):411-420
ATP-dependent Lon protease-deficient Salmonella enterica serovar Typhimurium (strain CS2022) appeared to invade successfully the mesenteric lymph nodes (MLN) and Peyer's patches (PP) of BALB/c mice and appeared to be easily eradicated by the host after oral immunization. As detected by flow cytometry, the population of major histocompatibility complex class I (MHC-I)-expressing macrophages and dendritic cells (DCs) was increased in the PP of mice immunized with CS2022 on day 6 after immunization. Thereafter, the population of splenic surface CD69(+) T lymphocytes prepared from mice immunized with CS2022 6 weeks prior to measurement increased as a result of the administration of the extracellular vesicles of RAW264.7 macrophage-like cells derived by Salmonella challenge. In addition, the proliferation of CD8(+) and even of CD4(+)T cells isolated from mouse spleens immunized with CS2022 was enhanced after cocultivation with naive DCs in the presence of the extracellular vesicles. These findings indicate that the extracellular vesicles prepared from the Salmonella-challenged macrophages carried salmonellae antigens to bystander DCs, thereby stimulating T-cell responses. Therefore, as antigen presentation after phagocytosis should be a central process in the T-cell activation that occurs in response to Salmonella infection, an oral immunization with CS2022 sufficiently induces T cell-mediated immunity in mice. 相似文献
149.
Moe Matsuo Tetsuhiro Shimodaira Takashi Kasama Yukie Hata Ayumi Echigo Masaki Okabe Kazuya Arai Yasutaka Makino Shin-Ichiro Niwa Hideyuki Saya Toshihiko Kishimoto 《PloS one》2013,8(11)
The completion of cytokinesis is crucial for mitotic cell division. Cleavage furrow ingression is followed by the breaking and resealing of the intercellular bridge, but the detailed mechanism underlying this phenomenon remains unknown. Katanin is a microtubule-severing protein comprised of an AAA ATPase subunit and an accessory subunit designated as p60 and p80, respectively. Localization of katanin p60 was observed at the midzone to midbody from anaphase to cytokinesis in rat cells, and showed a ring-shaped distribution in the gap between the inside of the contractile ring and the central spindle bundle in telophase. Katanin p60 did not bind with p80 at the midzone or midbody, and localization was shown to be dependent on microtubules. At the central spindle and the midbody, no microtubule growth plus termini were seen with katanin p60, and microtubule density was inversely correlated with katanin p60 density in the region of katanin p60 localization that seemed to lead to microtubule destabilization at the midbody. Inhibition of katanin p60 resulted in incomplete cytokinesis by regression and thus caused the appearance of binucleate cells. These results suggest that katanin p60 contributes to microtubule instability at the midzone and midbody and facilitates cytokinesis in rat cells. 相似文献
150.
The two forms of Stigmaeopsis miscanthi (Saito) (called LW and HG) differ in their levels of male-to-male aggression, differ in their diapause attributes, and morphologically in the male leg I armor. Furthermore, a type of reproductive isolation exists between the forms, although some one-way compatibility is maintained. Here we looked for any differences in life history traits between the two forms under experimental conditions. The intrinsic rate of natural increase (r m ) of the LW form was lower than that of the HG form, the difference seemingly caused by the developmental speed of the latter. Although the developmental speeds of HG under several temperature regimens were significantly higher than those of LW, the low development threshold temperatures of the two forms were almost identical. This study addresses why a significant difference in r m exists in relation to other behavior and physiological (diapause) adaptations. 相似文献