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991.
Yoshiki Shimatsu Wataru Horii Tetsuo Nunoya Akira Iwata Jianglin Fan Masayuki Ozawa 《Experimental Animals》2016,65(1):37-43
Most cases of ischemic heart disease and stroke occur as a result of atherosclerosis. The
purpose of this study was to produce a new Nippon Institute for Biological Science (NIBS)
miniature pig model by somatic cell nuclear transfer (SCNT) for studying atherosclerosis.
The human apolipoprotein(a) (apo(a)) genes were transfected into kidney epithelial cells
derived from a male and a female piglet. Male cells were used as donors initially, and 275
embryos were transferred to surrogates. Three offspring were delivered, and the production
efficiency was 1.1% (3/275). Serial female cells were injected into 937 enucleated
oocytes. Eight offspring were delivered (production efficiency: 0.9%) from surrogates. One
male and 2 female transgenic miniature pigs matured well. Lipoprotein(a) was found in the
male and one of the female transgenic animals. These results demonstrate successful
production of human apo(a) transgenic NIBS miniature pigs by SCNT. Our goal is to
establish a human apo(a) transgenic NIBS miniature pig colony for studying
atherosclerosis. 相似文献
992.
Yuichi Yashiro Yoshiaki Nomura Mikimoto Kanazashi Koji Noda Nobuhiro Hanada Yoshiki Nakamura 《PloS one》2014,9(5)
The periodontal ligament (PDL) is one of the connective tissues located between the tooth and bone. It is characterized by rapid turnover. Periodontal ligament fibroblasts (PDLFs) play major roles in the rapid turnover of the PDL. Microarray analysis of human PDLFs (HPDLFs) and human dermal fibroblasts (HDFs) demonstrated markedly high expression of chemokine (CXC motif) ligand 12 (CXCL12) in the HPDLFs. CXCL12 plays an important role in the migration of mesenchymal stem cells (MSCs). The function of CXCL12 in the periodontal ligament was investigated in HPDLFs. Expression of CXCL12 in HPDLFs and HDFs was examined by RT-PCR, qRT-PCR and ELISA. Chemotactic ability of CXCL12 was evaluated in both PDLFs and HDFs by migration assay of MSCs. CXCL12 was also immunohistochemically examined in the PDL in vivo. Expression of CXCL12 in the HPDLFs was much higher than that in HDFs in vitro. Migration assay demonstrated that the number of migrated MSCs by HPDLFs was significantly higher than that by HDFs. In addition, the migrated MSCs also expressed CXCL12 and several genes that are familiar to fibroblasts. CXCL12 was immunohistochemically localized in the fibroblasts in the PDL of rat molars. The results suggest that PDLFs synthesize and secrete CXCL12 protein and that CXCL12 induces migration of MSCs in the PDL in order to maintain rapid turnover of the PDL. 相似文献
993.
994.
Yoshikazu Izumi Hiroshi Morita Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(3):519-520
Several genes that may be involved in embryogenesis have been isolated from somatic embryos of carrot by many workers. However, the function of these genes has not been discovered yet. As the first step toward finding the function of these genes, we established a rapid and efficient method for transformation of carrot by using direct embryogenesis from hypocotyl segments treated with 2,4-dichlorophenoxyacetic acid (2,4-D) for a short period. 相似文献
995.
Motohiro Matsuura Nobuyuki Karai Yoshiki Tani Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(8):1717-1724
The intracellular concentration of vitamin B6 (B6) of a wild type strain (WG1) of Escherichia coli B remained almost constant (0.25 to 0.35 nmol per mg cells) when different amounts of B6 were extracellularly added. However, B6-requiring mutants were strongly affected by extracellular B6.Activities of tryptophanase in a B6-requiring mutant, strain WG3, grown under various conditions were measured. A clear correlation between intracellular B6 concentration and the ratio of holo-tryptophanase activity (i.e., holo-activity/total activity) was observed.Tryptophanase of strain WG3 grown under B6-deficient conditions and the enzyme of strain WG1 were purified and their properties compared. The purified enzymes of both strains WG3 and WG1 showed similar characteristics, but a difference was observed in the antigen activities. 相似文献
996.
997.
Effect of heating, freeze-drying, frozen storage and coagulation by chymosin on the exchangeability of colloidal calcium with soluble calcium in milk was investigated by the radioisotopic method previously reported. Heating at 100°C for 30 min caused a slight decrease of the exchangeability. Frozen storage at ?20°C for 120 days resulted in a marked decrease of the exchangeability accompanying a decrease of soluble calcium. Coagulation by chymosin gave no significant effect on the amount of soluble calcium or on the exchangeability of colloidal calcium. 相似文献
998.
Yoshiki Tsuchida Sakurako Kimura Nobuaki Suzuki Masayuki Inui Hideaki Yukawa 《Applied microbiology and biotechnology》2010,87(5):1855-1866
A 24-kb plasmid with 21 open reading frames (ORFs) was newly isolated from Corynebacterium glutamicum ATCC 14997 and named pCGR2. Three of its ORFs were indispensable for stable autonomous replication of pCGR2 in C. glutamicum: in the absence of selective pressure, deletion derivatives of pCGR2 containing the three ORFs showed stability in C. glutamicum for over 50 generations. The first of these ORFs encoded replicase repA whose gene product revealed high amino acid sequence similarity to corresponding gene products of C. glutamicum pCG1-family plasmids in general, and to that of pTET3 plasmid repA in particular. The other two ORFs were located upstream of repA and exhibited high sequence similarity to pTET3 parA and parB, respectively. Interestingly, plasmids based on the pCGR2 were compatible not only with those based on different family plasmids
(pBL1, pCASE1) but also with those based on pCG1-family plasmid. Plasmids comprising pCGR2 repA showed a copy number of four in C. glutamicum. The number increased to 240 upon introduction of a mutation within the repA origin of the putative promoter for counter-transcribed RNA. This 60-fold increase in copy number should immensely contribute
towards enhanced expression of desired genes in C. glutamicum. 相似文献
999.
1000.