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71.
The quantity of translatable mRNA of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ 1-oxidoreductase, EC 1.1.1.49) in primary cultures of adult rat hepatocytes subjected to different hormonal conditions was determined with a reticulocyte-lysate, cell-free system. The level of glucose-6-phosphate dehydrogenase mRNA was about 5-fold higher in the presence of insulin than in its absence. This increase of glucose-6-phosphate dehydrogenase mRNA reached a maximum 12 h after the addition of insulin. The maximum level of induction of glucose-6-phosphate dehydrogenase mRNA required 10(-8) M insulin. Glucagon and triiodothyronine had no effect on the glucose-6-phosphate dehydrogenase mRNA level. The increase of glucose-6-phosphate dehydrogenase activity correlated with the increase in level of mRNA of this enzyme. This suggests that the changes in glucose-6-phosphate dehydrogenase activity in response to the above hormonal changes are primarily due to changes in the amount of mRNA coding for this enzyme. 相似文献
72.
Jun Kikuchi Misato Hashizume Yuko Kaneko Keiko Yoshimoto Naoshi Nishina Tsutomu Takeuchi 《Arthritis research & therapy》2015,17(1)
IntroductionTocilizumab (TCZ), an anti-interleukin-6 receptor antibody, is clinically effective against rheumatoid arthritis (RA), and several reports have indicated how TCZ influences a number of mechanisms underlying RA pathogenesis. However, it is still unclear whether TCZ affects inflammatory cells in peripheral blood and whether any such changes are associated with clinical response. We evaluated associations between proportions of subsets of peripheral immune cells and clinical response in patients with RA treated with TCZ.MethodsThirty-nine consecutive patients with RA who started to receive TCZ as their first biologic between March 2010 and April 2012 were enrolled. The proportions of several subsets of peripheral cells with their levels of expression of differentiation markers, activation markers and costimulatory molecules were measured sequentially from baseline to week 52 by flow cytometry analysis.ResultsClinical Disease Activity Index (CDAI) remission was achieved in 53.8% of patients at week 52 of TCZ therapy. The proportions of CD4+CD25+CD127low regulatory T cells (Treg) and HLA-DR+ activated Treg cells significantly increased with TCZ therapy (P < 0.001 and P < 0.001, respectively), whereas proportions of CD3+CD4+CXCR3−CCR6+CD161+ T helper 17 cells did not change over the 52 weeks. The proportions of CD20+CD27+ memory B cells, HLA-DR+CD14+ and CD69+CD14+ activated monocytes, and CD16+CD14+ monocytes significantly decreased (P < 0.001, P < 0.001, P < 0.001 and P < 0.001, respectively). Among them, only the change in Treg cells was inversely correlated with the change in CDAI score (ρ = −0.40, P = 0.011). The most dynamic increase in Treg cells was observed in the CDAI remission group (P < 0.001).ConclusionThis study demonstrates that TCZ affected proportions of circulating immune cells in patients with RA. The proportion of Treg cells among CD4+ cells correlated well with clinical response.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0526-4) contains supplementary material, which is available to authorized users. 相似文献73.
Yoshimoto Tadashi Nakanishi Toshihiro Fukumoto Juichiro Tsuru Daisuke 《Bioscience, biotechnology, and biochemistry》2013,77(11):1775-1782
About 100 soil samples were subjected to screening for microorganisms which were capable of producing lytic enzyme toward Staphylococcus aureus. A strain belonging to Streptomyces was isolated and found to produce lytic enzyme(s) noninduciblly, when grown aerobically at 37°C for 25 hr in a medium containing 7.5% soybean cake extract, 2% dextrin, 0.6% K2HPO4, 0.02% each of MgSO4·7H2O and KCl, pH 7.0. The crude enzyme preparation was active at pH values of 8.5 and 5.8 toward S. aureus, B. subtilis, L. bulgaricus and Str. faecalis but was completely inert against M. lysodeikticus, indicating the enzyme(s) to be distinguished from other bacteriolytic enzymes of Streptomyces so far reported. 相似文献
74.
Proline specific endo- and exopeptidases 总被引:12,自引:0,他引:12
Roderich Walter William H. Simmons Tadashi Yoshimoto 《Molecular and cellular biochemistry》1980,30(2):111-127
Summary Peptidases which are specific for proline residues have been described and include endopeptidases (post-proline cleaving enzyme and proline specific endopeptidase), N-terminal exopeptidases (post-proline dipeptidyl aminopeptidase, proline iminopeptidase, aminopeptidase P), C-terminal exopeptidases (prolylcarboxypeptidase, and carboxypeptidase P) and dipeptidases (prolyl dipeptidase and proline dipeptidase). The properties, distinguishing characteristics, and possible significance of these proline specific endo- and exopeptidases are discussed. In addition, reference is made to a series of enzymes which can hydrolyze proline containing peptide bonds, but which are not specific for proline. 相似文献
75.
Yoshimoto T. Takahashi K. Nishimura H. Ajima A. Tamaura Y. Inada Y. 《Biotechnology letters》1984,6(6):337-340
Summary Lipoprotein lipase modified with polyethylene glycol dissolved in benzene, and catalyzed various reactions of ester synthesis, ester exchange and aminolysis. This modified enzyme had a high stability; 50% of the initial enzymic activity were retained after about 3 months-storage in benzene at room temperature. We can repeatedly re-use the enzyme by recovering from benzene solution; the enzyme precipitates upon addition of n-hexane(or petroleum ether). 相似文献
76.
Summary Two separate segments of plasmodial strands (Physarum polycephalum) generally contract and relax with different periods, but if the two are bridged with another small strand segment to make into a single system, the contraction cycles of the two previously separate segments become gradually unified under isometric as well as isotonic conditions. To clarify the possible role of the streaming endoplasm as the information carrier for synchronization, we stopped the streaming between two halves of a single strand either by cutting it or by using the double-chamber method without cutting it. When the endoplasm is prevented from flowing between the two halves of the same continuous system, which had been in good synchrony, their contraction-relaxation rhythms become out of phase with each other. After the endoplasm in the strand is allowed to stream freely again, the synchrony of their cyclic contraction is reestablished. It was concluded that endoplasm flowing back and forth in a plasmodial strand must carry a factor(s) which coordinates the period and phase of the contraction-relaxation cycle but does not control the amplitude of the cycle.The present work was supported in part by grants-in-aid from the Mitsubishi Foundation and the Japanese Ministry of Education, Science, and Culture. 相似文献
77.
Li SL Yamamoto T Yoshimoto T Uchihi R Mizutani M Kurimoto Y Tokunaga K Jin F Katsumata Y Saitou N 《Human genetics》2006,118(6):695-707
We have analyzed 105 autosomal polymorphic short tandem repeat (STR) loci for nine East and South-eastern Asian populations
(two Japanese, five Han Chinese, Thai, and Burmese populations) and a Caucasian population using a multiplex PCR typing system.
All the STR loci are genomewide tetranucleotide repeat markers of which the total number of observed alleles and the observed
heterozygosity were 756 and 0.743, respectively, for Japanese populations. Phylogenetic analysis for these allele frequency
data suggested that the Japanese populations are more closely related with southern Chinese populations than central and/or
northern ones. STRUCTURE program analysis revealed the almost clearly divided and accountable population structure at K=2–6, that the two Japanese populations always formed one group separated from the other populations and never belong to different
groups at K≥3. Furthermore, our new allele frequency data for 91 loci were analyzed with those for 52 worldwide populations published
by previous studies. Phylogenetic and multidimensional scaling (MDS) analyses indicated that Asian populations with large
population size (six Han Chinese, three Japanese, two Southeast Asia) formed one distinct cluster and are closer to each other
than other ethnic minorities in east and Southeast Asia. This pattern may be the caviar of comparing populations with greatly
differing population sizes when STR loci were analyzed. 相似文献
78.
The thermal stability of formaldehyde dehydrogenase (FaDH) from Pseudomonas sp. was examined and controlled by encapsulation in liposomes with β-reduced nicotinamide adenine dinucleotide (NADH). The activity of 4.8 μg/mL free FaDH at pH 8.5 in catalyzing the oxidation of 50 mM formaldehyde was highly dependent on temperature so that the activity at 60 °C was 27 times larger than that at 25 °C. Thermal stability of the FaDH activity was examined with and without liposomes composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). Rapid deactivation of free FaDH was observed at 60 °C because of its dissociation into two subunits. The rate of dissociative deactivation of POPC liposome-encapsulated FaDH was smaller than that of the free enzyme. The liposomal FaDH was however progressively deactivated for the incubation period of 60 min eventually leading to complete loss of its activity. The free FaDH and NADH molecules were revealed to form the thermostable binary complex. The thermal stability of POPC liposome-encapsulated FaDH and NADH system was significantly higher than the liposomal enzyme without cofactor. The above results clearly show that NADH is a key molecule that controls the activity and stability of FaDH in liposomes at high temperatures. 相似文献
79.
Tetsuya Fukui Akio Yoshimoto Mamoru Matsumoto Shunji Hosokawa Terumi Saito Hiroko Nishikawa Kenkichi Tomita 《Archives of microbiology》1976,110(2-3):149-156
The enzyme activity synthesizing poly--hydroxybutyrate (PHB) was mainly localized in the PHB-containing particulate fraction ofZoogloea ramigera I-16-M, when it grew flocculatedly in a medium supplemented with glucose. On the other hand, the enzyme activity remained in the soluble fraction, when the bacterium grew dispersedly in a glucose-starved medium.The soluble PHB synthase activity became associated with the particulate fraction as PHB synthesis was initiated on the addition of glucose to the dispersed culture. Conversely, the enzyme activity was released from the PHB-containing granules to the soluble fraction when the flocculated culture was kept incubated without supplementing the medium with glucose.PHB synthase was also incorporated into the newly formed PHB fraction when partially purified soluble PHB synthase was incubated withd(-)--hydroxybutyryl CoA in vitro.Although attempts to solubilize the particulate enzyme were unsuccessful, and the soluble enzyme became extremely unstable in advanced stages of purification, both PHB synthases had the same strict substrate specificity ford(-)--hydroxybutyryl CoA, and showed the same pH optimum at 7.0.Non-Standard Abbreviations PHB
poly--hydroxybutyrate 相似文献
80.
M Yamaguchi K Koike Y Yoshimoto H Ikegami A Miyake O Tanizawa 《Endocrinologia japonica》1991,38(4):357-361
The effects of human recombinant interleukin-1 beta and -6 and tumor necrosis factor-alpha (TNF-alpha) on the releases of PRL and dopamine were examined using monolayer cultures of rat pituitary cells and hypothalamic cells. The release of PRL from rat pituitary cells in 30 min was increased about 2-fold (p less than 0.05) by 10(5) U/l interleukin-1 beta, 10(5) U/l interleukin-6 or 100 micrograms/l TNF-alpha. TNF-alpha at 100 micrograms/l significantly increased PRL release within 5 min incubation and this effect continued throughout the next 30 min of incubation. Incubation for 5 min with TNF-alpha caused dose-dependent stimulation of PRL release. These cytokines did not modulate [3H]-dopamine release from primary cultures of hypothalamic cells. These results suggest that these cytokines stimulate PRL release directly at the pituitary gland, without modifying the release of dopamine from the hypothalamus. 相似文献