全文获取类型
收费全文 | 135篇 |
免费 | 2篇 |
国内免费 | 1篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 8篇 |
2013年 | 3篇 |
2012年 | 5篇 |
2011年 | 8篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 7篇 |
2007年 | 5篇 |
2006年 | 1篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有138条查询结果,搜索用时 31 毫秒
31.
A. M. Makarova T. S. Zamolodchikova L. D. Rumsh S. M. Strukova 《Russian Journal of Bioorganic Chemistry》2007,33(5):482-487
It was found that duodenase, a serine protease from the bovine duodenum, activates rat peritoneal mast cells (PMC) in vitro presumably via protease-activated receptors (PARs). Like thrombin (a serine protease from the blood coagulation system) and the PAR1 agonist peptide (PAR1-AP), duodenase was shown to accelerate the secretion of β-hexosaminidase (a marker of cell degranulation) by PMC in a dose-dependent manner. The blockage of the proteolytic activity of duodenase toward the substrate Tos-Gly-Pro-Lys-pNA by the soybean Bauman-Birk protease inhibitor substantially reduced (by 40%) the ability of duodenase to stimulate the secretory activity of PMC. Pretreatment of PMC with duodenase decreased the β-hexosaminidase secretion induced by thrombin and PAR1-AP by 35 and 41.7 %, respectively, and abolished the antiinflammatory effect of activated protein C. At the same time, pretreatment of PMC with duodenase did not affect the secretion of β-hexosaminidase induced by compound 48/80, a nonspecific degranulator of mast cells. Duodenase, unlike PAR1-AP (30–100 μM), in a broad concentration range (10–100 nM) did not induce aggregation of human platelets, but suppressed the platelet aggregation elicited by PAR1-AP. 相似文献
32.
Muhammad Toyabur Rahman SM Sohel Rana Md Salauddin Pukar Maharjan Trilochan Bhatta Jae Yeong Park 《Liver Transplantation》2020,10(12)
The fast growth of smart electronics requires novel solutions to power them sustainably. Portable power sources capable of harvesting biomechanical energy are a promising modern approach to reduce battery dependency. Herein, a novel elastic impact‐based nonresonant hybridized generator (EINR‐HG) is reported to effectively harvest biomechanical energy from diverse human activities outdoors. Through the rational integration of a nonlinear electromagnetic generator with two contact‐mode triboelectric nanogenerators, the proposed EINR‐HG generates hybrid electrical output simultaneously under the same mechanical excitations. By introducing a flux‐concentrator with a nanowire‐nanofiber surface modification, significant improvement in the energy harvesting efficiency of the EINR‐HG is achieved. After optimizing using simulations and vibration tests, the as‐fabricated EINR‐HG delivers an outstanding normalized power density of 3.13 mW cm?3 g?2 across a matching resistance of 1.5 kΩ at 6 Hz under 1 g acceleration. Under human motion testing, the EINR‐HG generates an optimal output power of 131.4 mW with horizontal handshaking. With a customized power management circuit, the EINR‐HG serves as a universal power source that successfully drives commercial smart electronics, including smart bands and smartphones. This work shows the massive potential of biomechanical energy‐driven hybridized generators for powering personal electronics and portable healthcare monitoring devices. 相似文献
33.
To assess the potential risks of using the artificial nanostructures the structural state of the human lymphocyte membrane and lipid peroxidation under the influence of multi-walled carbon nanotubes with metal impurities was studied. The ability of carbon nanotubes to induce the formation of reactive oxygen species in cells was examined. A dose-dependent increase in reactive oxygen species formation in lymphocytes, which was not registered in cells pre-incubated with N-acetylcystein, after exposure to carbon nanotubes was shown. The addition of iron chelator deferoxamine to carbon nanotubes has also resulted in a decrease of reactive oxygen species. The mechanism of the activation of lipid peroxidation under the influence of carbon nanotubes and a structural modification of human lymphocyte membranes were discussed. 相似文献
34.
Claire SM Kwan Rafael P Vázquez-Manrique Sung Ly Kshamata Goyal Howard A Baylis 《BMC physiology》2008,8(1):11
Background
Ultradian rhythms, rhythms with a period of less than 24 hours, are a widespread and fundamental aspect of life. The mechanisms underlying the control of such rhythms remain only partially understood. Defecation in C. elegans is a very tightly controlled rhythmic process. Underlying the defecation motor programme is an oscillator which functions in the intestinal cells of the animal. This mechanism includes periodic calcium release and subsequent intercellular calcium waves which in turn regulate the muscle contractions that make up the defecation motor programme. Here we investigate the role of TRPM cation channels in this process. 相似文献35.
Control of nematode parasites with reduced reliance on the use of anthelmintics was studied in 16 ewes with suckling twin
lambs on contaminated pasture in Denmark. Ewes and lambs were treated with albendazole at turn-out 3 May. Ewes were removed
from the groups on 26 July, and lambs were slaughtered on 11 October. The animals were allocated to 4 groups of 8 lambs and
their 4 ewes. Group TS was treated with albendazole at weeks 3, 6 and 8 after turnout and set-stocked; group TM was similarly
treated but moved to clean pasture in conjunction with the last drenching; group US was untreated and set-stocked, and group
UM was left untreated but moved to clean pasture week 8 after turn-out. Supplementary feed was offered in June and August
due to scarcity of pasture. Strategic treatments of ewes and lambs weeks 3, 6 and 8 after turn-out, with or without a move
to clean pasture, were highly effective in controlling nematode infections for most of the season. This was reflected in better
weight gains and carcass characteristics in the treated compared to untreated lambs, resulting in an average increase in the
value of the product by 36%. The effect of moving without treatment (UM) on faecal egg counts was limited but peak pasture
infectivity was reduced to less than 10% compared to the set-stocked group and weight gains of lambs were significantly better
despite poor feed availability in late season. The study showed that under set-stocked conditions repeated anthelmintic treatments
of both ewes and lambs in early season may ensure sufficient nematode control whereas moving animals to clean pasture without
dosing was less efficient. The latter may, however, still be a viable option in organic and other production systems where
routine use of anthelmintics is banned, particularly if weaning and moving are combined or a second move is performed. 相似文献
36.
Sequence of a cDNA for mouse thymidylate synthase reveals striking similarity with the prokaryotic enzyme 总被引:11,自引:0,他引:11
Perryman SM; Rossana C; Deng TL; Vanin EF; Johnson LF 《Molecular biology and evolution》1986,3(4):313-321
We report the nucleotide sequence of a cloned cDNA, pMTS-3, that contains a
1-kb insert corresponding to mouse thymidylate synthase (E.C. 2.1.1.45).
The open reading frame of 921 nucleotides from the first AUG to the
termination codon specifies a protein with a molecular mass of 34,962
daltons. The predicted amino acid sequence is 90% identical with that of
the human enzyme. The mouse sequence also has an extremely high degree of
similarity (as much as 55% identity) with prokaryotic thymidylate synthase
sequences, indicating that thymidylate synthase is among the most highly
conserved proteins studied to date. The similarity is especially pronounced
(as much as 80% identity) in the 44-amino-acid region encompassing the
binding site for deoxyuridylic acid. The cDNA sequence also suggests that
mouse thymidylate synthase mRNA lacks a 3' untranslated region, since the
termination codon, UAA, is followed immediately by a poly(A) segment.
相似文献
37.
38.
Karyagina Anna S. Gromov Alexander V. Grunina Tatyana M. Lyaschuk Alexander M. Poponova Maria S. Kleymenov Denis A. Strukova Natalia V. Generalova Maria S. Ryazanova Anna V. Galushkina Zoya M. Dobrynina Olga Yu. Bolshakova Tatyana N. Sergeeva Maria V. Romanovskaya-Romanko Ekaterina A. Krasilnikov Igor V. Subbotina Marina E. Lunin Vladimir G. 《Biochemistry. Biokhimii?a》2022,87(4):319-330
Biochemistry (Moscow) - Based on the previously developed approach, hybrid recombinant proteins containing short conformational epitopes (a.a. 144-153, 337-346, 414-425, 496-507) of the... 相似文献
39.
40.