首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   74篇
  免费   9篇
  83篇
  2021年   1篇
  2019年   2篇
  2016年   3篇
  2015年   3篇
  2014年   2篇
  2013年   4篇
  2012年   5篇
  2011年   5篇
  2010年   4篇
  2008年   1篇
  2007年   4篇
  2006年   1篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   1篇
  2001年   1篇
  2000年   3篇
  1999年   5篇
  1998年   6篇
  1994年   2篇
  1993年   2篇
  1992年   1篇
  1991年   3篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1984年   1篇
  1982年   2篇
  1981年   1篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1975年   4篇
  1974年   3篇
  1971年   2篇
  1968年   1篇
排序方式: 共有83条查询结果,搜索用时 15 毫秒
1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
2.
The results of liposome drug encapsulation of aclarubicin (aclacinomycin A), an antitumor antibiotic, are presented. The method of flow detergent dialysis was applied. Conditions providing maximum encapsulation of aclarubicin (the ratio of lipid components and the lipid/detergent ratio), as well as conditions providing stability of liposomal emulsion (the presence of antioxidants, stearic acid and cholesterol) were defined.  相似文献   
3.
4.
A total of 351 auxotrophic mutants with different antibiotic activity, including several mutants with activity higher than that of the parent prototrophic strains were obtained under the effect of gamma-rays from 3 prototrophic strains of Act. coeruleorubidus. It was shown that most of the auxotrophic mutants did not preserve the property of biochemical insufficiency on passages on complete media. A mutant strain 1059-32 with activity 2 times higher than that of the prototrophic strain 2-39 and the parent auxotrophic culture was obtained from the revertants. Requirements in 29 growth factors including 17 amino acids, 4 nitrous bases, 8 vitamins and coenzymes were determined in 46 stable auxotrophic mutants isolated. The effect of the specific and non-specific growth factors on the culture antibiotic production was studied.  相似文献   
5.
The aim of this study was to assess the involvement of eosinophil cationic protein, a marker of eosinophil activation, in the development of in-stent restenosis after drug-eluting stent implantation. Follow-up angiography at 6 to 12?months was performed in 32 patients who were treated with percutaneous coronary intervention and implantation of sirolimus-eluting stents. Blood plasma levels of eosinophil cationic protein (ECP) and total immunoglobulin E (IgE) were measured by enzyme-linked immunosorbent assay and the level of C-reactive protein (hs-CRP) by high-sensitivity nephelometry. According to angiography data, in-stent restenosis occurred in 13 patients, while 19 patients did not develop it. There were no differences between the hs-CRP and IgE levels in patients with or without restenosis. In contrast, ECP level was higher in patients with restenosis compared with that in patients without restenosis [17.7?ng/mL (11.2-24.0) vs. 9.0?ng/mL (6.4-12.9), p?= 0.017]. The incidence of in-stent restenoses was 63% in patients with ECP level higher than or equal to 11?ng/mL, and 19% in patients with an ECP level lower than 11?ng/mL (p?= 0.019). These findings suggest that elevated eosinophil activation may play an important role in the pathogenesis of in-stent restenosis after implantation of drug-eluting stents.  相似文献   
6.
7.
The composition and distribution of the main unicellular eukaryotic groups (diatom algae, ciliates, dinoflagellates (DF), other phototrophic (PF) and heterotrophic flagellates (HF)) were investigated in sandy sediments at five stations allocated across the tidal sheltered beach of the White Sea. Overall, 75 diatoms, 98 ciliates, 16 DF, 3 PF and 34 HF species were identified; some are new records for the White Sea. Common species for each group are illustrated. Diatoms and ciliates showed high alpha-diversity (species richness per sample), whereas flagellates were characterized by high beta-diversity (species turnover across the intertidal flat). Each group demonstrated its own spatial pattern that was best matched with its own subset of abiotic variables, reflecting group-specific responses to environmental gradients. Species richness increased from the upper intertidal zone seaward for ciliates but decreased for HF, whereas autotrophs showed a relatively uniform pattern with a slight peak at the mid-intertidal zone. Across the littoral zone, all groups showed distinct compositional changes; however, the position of the boundary between “upper” and “lower” intertidal communities varied among groups. Most of the species found at Ryazhkov Island are known from many other regions worldwide, indicating a wide geographic distribution of microbial eukaryotic species.  相似文献   
8.
9.
Encapsulation of enzymes (lactate dehydrogenase and urease) in polyelectrolyte shells was assessed with a view to designing enzymic microdiagnostics for low-molecular compounds in native biological fluids. Polyelectrolyte microcapsules were prepared with two polyanions [poly(styrenesulfonate) PSS and dextran sulfate DS] and two polycations [poly(allylamine) PAA and poly(diallyldimethylammonium) PDADMA]; calcium carbonate microspherulites with embedded enzymes served as “cores.” It was demonstrated that the main problem in making such a biosensor is to select a pair of oppositely charged polyelectrolytes that would be optimal for enzyme functioning. The best pairs were PAA/DS and PAA/PSS for lactate dehydrogenase, and PSS/PAA and PSS/PDADMA for urease. We designed and prepared enzyme-containing microcapsules differing in polyelectrolyte composition and number of layers, and investigated their properties.  相似文献   
10.
A new thecate, photosynthetic, sand‐dwelling marine dinoflagellate, Laciniporus arabicus gen. et sp. nov., is described from the subtidal sediments of the Omani coast in the Arabian Sea, northern Indian Ocean, based on detailed morphological and molecular data. Cells of L. arabicus are small (16.2–30.1 μm long and 13.1–23.2 μm wide), dorsoventrally compressed, with a small apical flap‐shaped projection pointing to the left. The thecal plate pattern is distinguished by minute first precingular plate and sulcus, which extends into the epitheca, with large anterior and right sulcal plates. The Kofoidian thecal tabulation is Po, X, 4′, 2a, 7′′, 6c, 6s, 5′′′, 2′′′′. Morphologically, the revealed plate pattern has an affinity to the Peridiniales, and LSU rDNA based phylogenetic analyses placed L. arabicus within the Thoracosphaeraceae, close to calcareous‐cyst producing scrippsielloids, predatory pfiesteriaceans, and photosynthetic freshwater peridinioids Chimonodinium lomnickii and Apocalathium spp. However, the thecal plate arrangement of L. arabicus differs noticeably from any currently described dinoflagellates, and the species stands out from closely related taxa by extensive differences in physiology and ecology.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号