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991.
Masayoshi Saito Takao Yamaguchi Tetsuya Kawata Hisao Ito Takao Kanai Masaru Terada Makoto Yokosuka Toru R Saito 《Experimental Animals》2006,55(5):477-481
As a model for studying methamphetamine (MAP) abuse, which has become a social problem in Japan, we investigated the changes in serum cortisone, NK cell activity and mitogenic response of T-lymphocytes after a single injection of MAP (3.0 mg/kg) in female cynomolgus monkeys. Serum cortisol concentration was significantly elevated to 2.66 times pre-injection levels at 6 h post-injection, and the effect was still observed 24 h later. NK cell activity was significantly elevated at 6 h after MAP injection, but at 24 h after injection had dropped markedly to 49.5% of baseline. Mitogen (PHA) response of lymphocytes was elevated when MAP was injected, and this increased level continued up to 24 h. We speculate that the transient increase in NK cell activity followed by a distinct drop, as well as the changes in T-lymphocytes, may be strongly related to the cortisone concentration. 相似文献
992.
Shin Ohtani Yusuke Shinkai Akio Horibe Kentaro Katayama Takehito Tsuji Yoshibumi Matsushima Masayoshi Tachibana Tetsuo Kunieda 《Experimental Animals》2006,55(5):491-495
The WS4 mouse is an animal model for human Waardenburg syndrome type 4 (WS4), showing pigmentation anomalies, deafness and megacolon, which are caused by defects of neural crest-derived cells. We have previously reported that the gene responsible for the WS4 mouse is an allele of the piebald mutations of the endothelin B receptor gene (Ednrb). In this study, we examined the genomic sequence of the Ednrb gene in WS4 mice and found a 598-bp deletion in the gene. The deleted region contains the entire region of exon 2 and the 5' part of exon 3 and is flanked by inverted repeat sequences which are suggested to trigger the deletion. We concluded that the deletion in the Ednrb gene is the causative mutation for the phenotype of WS4 mice. 相似文献
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994.
995.
Veillonellophage N2 adsorbed to polysaccharides (PSs) on Veillonella rodentium ATCC 17743 cell wall, and the bacteriophage receptor contained only glucosamine. D(+)-glucosamine hydrochloride (Sigma) also adsorbed the veillonellophage N2. These results therefore indicate that the receptor to the veillonellophage N2 is cell wall PSs. The PSs of the host cells as receptor have been characterized. Glucosamine accounted for approximately 100% of the weight of the PSs. The PSs which were partially resolved by Sephadex G-75 chromatography comprised approximately four glucosamine units. Their primary structure was determined by 400 MHz n.m.r. spectroscopy. One- and two-dimensional 1H-nmr experiments showed the PS to be a branched polymer. Glucosamine linkage was detected in one of the branches. 相似文献
996.
997.
A Yongsiri T Goto B S Ku H Takeuchi M Namba 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1986,85(1):233-238
Morphological and pharmacological investigations were made of two giant neurons, RPeNLN (right pedal nerve large neuron) and LPeNLN (left pedal nerve large neuron), situated symmetrically on the anterior surface of the pedal ganglia of an African giant snail (Achatina fulica Férussac). The two neurons (about 250-300 microns in diameter) were the largest ones identified in the ganglia of the snail species. The axonal pathways of the two neurons were symmetrical; of their four main axonal branches, the three main branches innervated the ipsilateral pedal nerves, whereas the last main branch projected to the contralateral pedal nerves. The pharmacological features of the two neurons were very similar. Both were inhibited markedly by dopamine [minimum effective concentrations (MECs): 3 X 10(-6)-10(-5) M], DL-octopamine (MECs: 2 X 10(-6)-2 X 10(-5) M), 5-hydroxytryptamine (MEC: 3 X 10(-6) M), GABA (MEC: 3 X 10(-4) M), L-homocysteic acid (MECs: 3 X 10(-5)-10(-4) M) and erythro-beta-hydroxy-L-glutamic acid (MEC: 3 X 10(-5) M). Acetylcholine showed varied effects, either excitatory or inhibitory, on the two neurons examined. No substances were found to have any marked excitatory effects on the neurons. 相似文献
998.
Masayoshi Nakayama Hisakazu Yamane Isomaro Yamaguchi Noboru Murofushi Nobutaka Takahashi Masayuki Katsumi 《Journal of Plant Growth Regulation》1989,8(3):237-247
Endogenous gibberellins (GAs) in the shoots of normal- (cv. Yomaki, YO) and bush-type (cv. Spacemaster, SP) cultivars of cucumber
(Cucumis sativus L.) grown under natural conditions were analyzed. From both YO and SP grown for 40 days, after sowing, a series of C-13-H
GAs including GA4, GA9, GA15, GA24, GA25, GA34, and GA51 were identified by gas chromatography-mass spectrometry (GC-MS; full scan). In addition to the above GAs, GA12 and GA70 were similarly identified from both YO and SP grown for 61 days after sowing. The endogenous levels of GA4 and GA9, which are highly active in promoting cucumber hypocotyl elongation, were quantified by GC-selected ion monitoring (GC-SIM)
using [2H2]GA4 and [2H4]GA9 as internal standards. No remarkable difference in terms of endogenous levels of GA4/9 was observed between YO and SP in both growth stages (40 and 61 days after sowing). 相似文献
999.
Transforming growth factor beta 1 (1 ng/ml) caused death of serum-free mouse embryo cells cultured in a medium consisting of a 1:1 mixture of Dulbecco's Modified Eagle's medium and Ham's F12 medium supplemented with fibronectin, insulin, transferrin, epidermal growth factor, and high density lipoprotein. Cell death occurred in the presence of polyunsaturated fatty acids including linoleic acid in the absence of selenium. The death could be reversed by adding -tocopherol to the culture indicating a mechanism involving fatty acid peroxidation. Butylated hydroxytoluene was a poor suppressor of cell death in contrast to -tocopherol. High density lipoprotein and fatty acid-free albumin also suppressed cell death at the level of 20 g/ml and 1 mg/ml, respectively. Transforming growth factor 1 also caused a low rate of cell growth after heat treatment of the cells at 45°C.Abbreviations HDL
high density lipoprotein
- SFME cell
serum-free mouse embryo cell
- TGF1
transforming growth factor 1 相似文献
1000.
Toshihiro Fujimoto Kazuhiko Omote Masayoshi Mai Shunnosuke Natsuume-Sakai 《Biotherapy》1992,5(2):153-163
Peripheral blood lymphocytes (PBL) of gastric cancer patients in advanced stages showed lymphokine activated killer (LAK) activities comparable to those of healthy donors, suggesting potential applicability of LAK cells induced from PBL stimulated with recombinant interleukin-2 (rIL-2) in adoptive immunotherapy (AIT) for gastric cancer. In order to generate a large number of LAK cells from PBL, lymphocytes were cultured with both rIL-2 and phytohemagglutinin (PHA). In this culture, the numbers of cells increased to a greater extent than those in culture with rIL-2 alone but cytotoxic activity did not augment, thus suggesting that this procedure would not afford sufficient clinical effects. On the other hand, a large number of LAK cells with high anti-tumor activities were efficiently induced from spleen cells of the patients by culture of rIL-2; hence clinical usefulness of these LAK cells is anticipated. In regional lymph node lymphocytes (RLNL) cultured with rIL-2, the cytotoxic activities were lower than in those induced in PBL, and a characteristic increase of CD8 + CD11 + suppressor T cells was observed after incubation with rIL-2. Nevertheless, an increase of CD4 + 4B4+ helper inducer T cells was also observed in RLNL after the culture with rIL-2. Furthermore, high cytotoxic activities were induced in RLNL in some cases in which metastasis to the regional lymph nodes was not detected. When gastric cancer patients were pretreated with biological response modifiers (BRM), especially with Lentinan, LAK cells from PBL showed higher NK and LAK activities as compared with those of patients without BRM pretreatment.This work was partly supported by a grant from Hokkoku Cancer Research Foundation. 相似文献