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The characterization of 66 kDa protein molecule, a major protein component which is produced from femoral-diaphyseal tissues with fracture healing (Igarashi and Yamaguchi [2002] Int. J. Mol. Med. 9:503-508), was investigated. Weaning rats were killed at 7 and 14 days after femoral fracture. When the femoral-diaphyseal tissues with fracture healing were cultured for 48 h in a serum-free medium, many proteins in the bone tissues were released into the medium. Analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that a protein molecule of approximately 66 kDa was markedly increased in culture medium from bone tissues with fracture healing. N-terminal sequencing of 66 kDa protein indicated that its N-terminus was identical to that of rat albumin. Western blot analysis of medium 66 kDa protein showed expression of albumin. This expression was significantly enhanced by fracture healing. The expression of albumin was seen in the diaphyseal (cortical bone) and metaphyseal (trabecular bone) tissues of rat femur. When the femoral-diaphyseal tissues obtained at 7 days after femoral fracture were cultured in a serum-free medium containing either vehicle, parathyroid hormone (1-34) (10(-7) M), insulin-like growth factor-I (10(-8) M) or zinc acexamate (10(-4) M), medium albumin was significantly increased in the presence of those bone-stimulating factors. The addition of albumin (0.5 or 1.0 mg/ml of medium) caused a significant increase in calcium and deoxyribonucleic acid contents in the femoral-diaphyseal and -metaphyseal tissues obtained from normal rats in vitro. The present study demonstrates that fracture healing induces a remarkable production of albumin which is a major protein component produced from femoral-diaphyseal tissues of rats, and that albumin has an anabolic effect on bone components. 相似文献
33.
The so-called Glires hypothesis postulates a sister-group relationship between Rodentia (e.g., rat and mouse) and Lagomorpha (e.g., rabbit). Recent molecular phylogenetic analyses have yielded incongruent results, and either supported or refuted the Glires grouping. In order to study this inconsistency we have reconstructed phylogenetic trees based on data sets of 20 orthologous nuclear protein coding genes (6441 aa, sites) and 12 mitochondrial protein coding genes (3559 aa sites). The size of the nuclear data set is considerably larger than any comparable data set hitherto used to study the Glires concept. Analysis of the nuclear data strongly supported the phylogenetic tree (frog, chicken, ((rat, mouse), (rabbit, (human, (cattle, dog))))), while the mt data could not conclusively resolve the position of rabbit relative to that of human. This result was supported by all methods. Thus, the Glires hypothesis was rejected by this study. 相似文献
34.
Inoue H Tsukita K Iwasato T Suzuki Y Tomioka M Tateno M Nagao M Kawata A Saido TC Miura M Misawa H Itohara S Takahashi R 《The EMBO journal》2003,22(24):6665-6674
Mutant copper/zinc superoxide dismutase (SOD1)-overexpressing transgenic mice, a mouse model for familial amyotrophic lateral sclerosis (ALS), provides an excellent resource for developing novel therapies for ALS. Several observations suggest that mitochondria-dependent apoptotic signaling, including caspase-9 activation, may play an important role in mutant SOD1-related neurodegeneration. To elucidate the role of caspase-9 in ALS, we examined the effects of an inhibitor of X chromosome-linked inhibitor of apoptosis (XIAP), a mammalian inhibitor of caspase-3, -7 and -9, and p35, a baculoviral broad caspase inhibitor that does not inhibit caspase-9. When expressed in spinal motor neurons of mutant SOD1 mice using transgenic techniques, XIAP attenuated disease progression without delaying onset. In contrast, p35 delayed onset without slowing disease progression. Moreover, caspase-9 was activated in spinal motor neurons of human ALS subjects. These data strongly suggest that caspase-9 plays a crucial role in disease progression of ALS and constitutes a promising therapeutic target. 相似文献
35.
Shibata H Hanazono Y Ageyama N Nagashima T Ueda Y Hasegawa M Ozawa K Yoshikawa Y Terao K 《American journal of primatology》2003,61(1):3-12
Previous studies have shown that hematopoietic progenitor cells can be isolated from human or nonhuman primate bone marrow (BM) cells. In the present study, we studied the cross-reactivity of 13 anti-human CD34, two anti-human c-Kit, and one anti-human CD133 monoclonal antibodies (mAbs) with cynomolgus macaque (Macaca fascicularis) BM cells, using flow cytometric analysis, cell enrichment, and clonogenic assay. Among the 13 anti-human CD34 mAbs assessed, six cross-reacted as previously reported by other groups. However, only three of these six mAbs (clones 561, 563, and 12.8) recognized cynomolgus CD34+ cells that formed progenitor colonies when grown in methylcellulose culture. Similarly, of the two anti-human c-Kit mAbs (clones NU-c-kit and 95C3) that were previously reported to cross-react with cynomolgus BM cells, only one (clone NU-c-kit) resulted in a similar outcome. The anti-human CD133 mAb (clone AC133) also cross-reacted with cynomolgus BM cells, although these cells did not give rise to colonies when grown in culture. These results suggest that antibodies that cross-react with nonhuman primate cells may not identify the hematopoietic cells of interest. In addition, while the CD34 mAb (clone 561) results in the selection of hematopoietic progenitor cells of all lineages when assessed in methylcellulose culture, the c-Kit(high) fraction (NU-c-kit) exclusively identifies erythroid-specific progenitor cells after growth in culture. It is important to consider these findings when selecting cross-reacting mAbs to identify cells of hematopoietic lineages in macaque species. 相似文献
36.
Elevation of the provitamin A content of transgenic tomato plants 总被引:31,自引:0,他引:31
Römer S Fraser PD Kiano JW Shipton CA Misawa N Schuch W Bramley PM 《Nature biotechnology》2000,18(6):666-669
Tomato products are the principal dietary sources of lycopene and major source of beta-carotene, both of which have been shown to benefit human health. To enhance the carotenoid content and profile of tomato fruit, we have produced transgenic lines containing a bacterial carotenoid gene (crtI) encoding the enzyme phytoene desaturase, which converts phytoene into lycopene. Expression of this gene in transgenic tomatoes did not elevate total carotenoid levels. However, the beta-carotene content increased about threefold, up to 45% of the total carotenoid content. Endogenous carotenoid genes were concurrently upregulated, except for phytoene synthase, which was repressed. The alteration in carotenoid content of these plants did not affect growth and development. Levels of noncarotenoid isoprenoids were unchanged in the transformants. The phenotype has been found to be stable and reproducible over at least four generations. 相似文献
37.
Production of the Carotenoids Lycopene, β-Carotene, and Astaxanthin in the Food Yeast Candida utilis 下载免费PDF全文
Yutaka Miura Keiji Kondo Toshiko Saito Hiroshi Shimada Paul D. Fraser Norihiko Misawa 《Applied microbiology》1998,64(4):1226-1229
The food-grade yeast Candida utilis has been engineered to confer a novel biosynthetic pathway for the production of carotenoids such as lycopene, β-carotene, and astaxanthin. The exogenous carotenoid biosynthesis genes were derived from the epiphytic bacterium Erwinia uredovora and the marine bacterium Agrobacterium aurantiacum. The carotenoid biosynthesis genes were individually modified based on the codon usage of the C. utilis glyceraldehyde 3-phosphate dehydrogenase gene and expressed in C. utilis under the control of the constitutive promoters and terminators derived from C. utilis. The resultant yeast strains accumulated lycopene, β-carotene, and astaxanthin in the cells at 1.1, 0.4, and 0.4 mg per g (dry weight) of cells, respectively. This was considered to be a result of the carbon flow into ergosterol biosynthesis being partially redirected to the nonendogenous pathway for carotenoid production. 相似文献
38.
Identification and Characterization of a Constitutively Active STAT5 Mutant That Promotes Cell Proliferation 总被引:26,自引:2,他引:24 下载免费PDF全文
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40.
Yasuhiro Moriwaki Kiyoko Takada Toshinori Nagasaki Natsuki Kubo Tomohiro Ishii Kazuaki Kose Taihei Kageyama Shoutaro Tsuji Koichiro Kawashima Hidemi Misawa 《PloS one》2015,10(10)