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   24篇
  免费   1篇
化学工业   14篇
机械仪表   2篇
水利工程   1篇
一般工业技术   6篇
冶金工业   1篇
自动化技术   1篇
  2022年   2篇
  2021年   2篇
  2020年   1篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2013年   2篇
  2012年   3篇
  2011年   2篇
  2010年   2篇
  1998年   1篇
  1997年   3篇
  1991年   1篇
  1986年   1篇
  1984年   1篇
排序方式: 共有25条查询结果,搜索用时 31 毫秒
1.
Human red blood cells (RBCs) are unique cells with the remarkable ability to deform, which is crucial for their oxygen transport function, and which can be significantly altered under pathophysiological conditions. Here we performed ultrastructural analysis of RBCs as a peripheral cell model, looking for specific signatures of the neurodegenerative pathologies (NDDs)—Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD), utilizing atomic force (AFM) and conventional optical (OM) microscopy. We found significant differences in the morphology and stiffness of RBCs isolated from patients with the selected NDDs and those from healthy individuals. Neurodegenerative pathologies’ RBCs are characterized by a reduced abundance of biconcave discoid shape, lower surface roughness and a higher Young’s modulus, compared to healthy cells. Although reduced, the biconcave is still the predominant shape in ALS and AD cells, while the morphology of PD is dominated by crenate cells. The features of RBCs underwent a marked aging-induced transformation, which followed different aging pathways for NDDs and normal healthy states. It was found that the diameter, height and volume of the different cell shape types have different values for NDDs and healthy cells. Common and specific morphological signatures of the NDDs were identified.  相似文献   
2.
The subject of this research is the thermodynamics of the adsorption equilibrium of three types of bleached pulp in water solutions of aliphatic amidpolyamine—Lamid-1, (L-1) in concentrations from 0.03 to 0.50 g/L in a temperature interval of 0–60°C and the influence of pH of the environment on the adsorption process. It was established that with the increase of temperature the quantity of adsorbed L-1 decreases. The values of the heat of adsorption are negative, do not depend on the quantity of adsorbed L-1, and are of the order 111.7–14.7 kJ/mol. The values of the entropy of the entropy of adsorption are also negative and are of the order of 76.8 ÷ 84.5 J/mol?K. Adsorption equilibrium is described by ther adsorption isotherm of Langmuir. Optimum pH for lower concentrations of the solution is from 5 to 7. When the concentrations of the solution are higher (C ≧ 0.15 g/L) the process can also take place very satisfactorily in an alkaline environment.  相似文献   
3.
One of the most widely used and important groups of functional dyes are the styryl dyes and a review of this functional dye class has not been published for more than 15 years. In this review article, we describe the new trends in the synthesis of a range of novel intermediates and styryl dyes and include the most interesting examples of their high‐tech applications. However, this review is not intended to be comprehensive because of the large number of styryl dye studies that have been carried out in this time. Styryl cyanine dyes are widely used in optical recording media in laser discs, as flexible dyes, laser dyes, as optical sensitisers and in various other fields, for example dye‐sensitised solar cells and dyes with non‐linear optical properties. Additionally, the most important applications for these dyes are in bio‐labelling and in medicinal analysis.  相似文献   
4.
5.
This study will evaluate the safety and efficacy of allogenic donor lymphocyte infusions in patients who have relapsed hematologic malignancies after allogeneic bone marrow transplantation (BMT). Donor lymphocyte transfusions have resulted in the cure of some patients with relapsed leukemia or lymphoproliferative disorder after allogeneic BMT, but has been complicated by the development of graft versus host disease (GvHD). We hypothesize that a retroviral vector containing the Herpes simplex thymidine kinase (HStk) gene will allow for retention of the anti-leukemia response of transfused donor lymphocytes while allowing for the adverse effects of GVHD to be mitigated. Patients with relapsed hematologic malignancies after allogeneic BMT will be infused with ex vivo gene modified donor lymphocytes. The Herpes Simplex thymidine kinase (HStk) gene will be transduced into the cells ex vivo using LTKOSN. 1 vector supernate. Insertion of the HStk gene into lymphocytes confers a sensitivity to the anti-herpes drug ganciclovir (GCV). This selective destruction of donor lymphocytes in situ will be used to abrogate the effect of graft versus host disease, if it develops.  相似文献   
6.
This paper introduces a linear array for spelling correction using 15 processors. Many architectures have been proposed to solve similar string correction problems such as speech recognition or nucleic acid sequence computation. It is known that the hypercube, de Bruijn and grid networks contain a Hamiltonian path, a path which contains all the vertices of the network. The execution time of spelling correction on all of these networks is equal. © 1997 John Wiley & Sons, Ltd.  相似文献   
7.
We prove that an automorphism of order 3 of a putative binary self-dual $[120, 60, 24]$ [ 120 , 60 , 24 ] code $C$ C has no fixed points. Moreover, the order of the automorphism group of $C$ C divides $2^a\cdot 3 \cdot 5\cdot 7\cdot 19\cdot 23\cdot 29$ 2 a · 3 · 5 · 7 · 19 · 23 · 29 with $a\in \mathbb N _0$ a ∈ N 0 . Automorphisms of odd composite order $r$ r may occur only for $r=15, 57$ r = 15 , 57 or $r=115$ r = 115 with corresponding cycle structures $3 \cdot 5$ 3 · 5 - $(0,0,8;0), 3\cdot 19$ ( 0 , 0 , 8 ; 0 ) , 3 · 19 - $(2,0,2;0)$ ( 2 , 0 , 2 ; 0 ) or $5 \cdot 23$ 5 · 23 - $(1,0,1;0)$ ( 1 , 0 , 1 ; 0 ) respectively. In case that all involutions act fixed point freely we have $|\mathrm{Aut}(C)| \le 920$ | Aut ( C ) | ≤ 920 , and $\mathrm{Aut}(C)$ Aut ( C ) is solvable if it contains an element of prime order $p \ge 7$ p ≥ 7 . Moreover, the alternating group $\mathrm{A}_5$ A 5 is the only non-abelian composition factor which may occur in $\mathrm{Aut}(C)$ Aut ( C ) .  相似文献   
8.
The dependence of the fluorescence intensity of Cs vapor irradiated by elliptically polarized light resonant with the F = 4 ?? F = 5 transition on the scanned magnetic field has a complex shape ?? a narrow dip against the background of a broad peak. It is found experimentally that the dip is due to the small component of the magnetic field orthogonal to the direction of the laser beam. A two-level atom model with degenerate angular-momentum states predicts an order of magnitude lower contrast of this dip. The experimentally observed contrast of the dip can be explained by assuming that due to the low buffer-gas pressure in the optical cell, part of the resonant atoms is able to return to the laser beam without thermalized collisions with the wall of the cell, increasing the contrast. In addition, accounting for all optical transitions of the D 2-line and the optical pumping of the hyperfine-structure components of the ground state is a fundamental point for the interpretation of the experimental results.  相似文献   
9.
The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic acid, were also found in V. alginolyticus. The alga contained 43% saturated fatty acids, and 28% C16–C20 polyunsaturated fatty acids of the n−3 and n−6 families.  相似文献   
10.
Single-walled carbon nanotubes (SWCNTs) emerge as promising novel carbon-based nanoparticles for use in biomedicine, pharmacology and precision agriculture. They were shown to penetrate cell walls and membranes and to physically interact and exchange electrons with photosynthetic complexes in vitro. Here, for the first time, we studied the concentration-dependent effect of foliar application of copolymer-grafted SWCNTs on the structural and functional characteristics of intact pea plants. The lowest used concentration of 10 mg L−1 did not cause any harmful effects on the studied leaf characteristics, while abundant epicuticular wax generation on both leaf surfaces was observed after 300 mg L−1 treatment. Swelling of both the granal and the stromal regions of thylakoid membranes was detected after application of 100 mg L−1 and was most pronounced after 300 mg L−1. Higher SWCNT doses lead to impaired photosynthesis in terms of lower proton motive force generation, slower generation of non-photochemical quenching and reduced zeaxanthin content; however, the photosystem II function was largely preserved. Our results clearly indicate that SWCNTs affect the photosynthetic apparatus in a concentration-dependent manner. Low doses (10 mg L−1) of SWCNTs appear to be a safe suitable object for future development of nanocarriers for substances that are beneficial for plant growth.  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