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   25篇
  免费   1篇
  2021年   1篇
  2013年   1篇
  2008年   1篇
  2007年   2篇
  2005年   1篇
  2004年   1篇
  2001年   2篇
  1999年   1篇
  1995年   1篇
  1993年   2篇
  1992年   3篇
  1991年   1篇
  1979年   1篇
  1978年   1篇
  1975年   1篇
  1974年   2篇
  1972年   2篇
  1970年   2篇
排序方式: 共有26条查询结果,搜索用时 31 毫秒
1.
For many years, membrane potential (Vm) and input resistance have been used to characterize the electrophysiological nature of a seal (barrier) that forms at the cut end of a transected axon or other extended cytoplasmic structure. Data from a mathematical and an analog model of a transected axon and other theoretical considerations show that steady-state values of Vm and input resistance measured from any cable-like structure provide a very equivocal assessment of the electrical barrier (seal) at the cut end. Extracellular assessments of injury currents almost certainly provide a better electrophysiological measure of the status of plasma membrane sealing because measurements of these currents do not depend on the cable properties of extended cytoplasmic processes after transection.  相似文献   
2.
The effectiveness and safety of the immunization of children with adsorbed DT toxoid with reduced component with disturbances in the reactivity of the body, caused by immunosuppressive therapy, are evaluated. The group under study included 53 children with glomerulonephritis, malignant tumors and acute lymphoblast leucosis, formerly receiving immunosuppressive drugs. The control group consisted of 24 patients with pyelonephritis who had not received such therapy. In the postvaccinal period no exacerbation of the main disease was registered in children. The manifestation and frequence of postvaccinal reactions did not differ from those observed in healthy children after the injection of adsorbed DT toxoid with reduced antigen content. Control serological testing demonstrated the presence of pronounced immune response in the vaccinees.  相似文献   
3.
The Kinetic approach to the problem of the RNA structure prediction based on the analysis of the molecule self-formation is proposed. Re-structurization that occurs during processing is described in terms of Markov processes. A new formalism designating nucleotides by complex numbers is proposed, leading to the complex unitary space of nucleic vectors. Properties of structure and transition matrices are discussed in relation to the analysis of RNA structural formation processes. The non-linear dynamic behavior of secondary structure transitions is analyzed. Soliton-like oscillations of RNA and DNA tertiary structures are predicted. The Monte-Carlo simulation of the RNA structure self-formation is used to calculate the ensemble of the secondary structures of the tRNAAla precursor from Bombix mori formed during processing.  相似文献   
4.
5.
As shown recently, the set of electronic configurations of all chemical elements in the subshell partitioning has a four-dimensional structure. Hence, all elements can be subdivided into cycles and supercycles rather than into periods of the conventional Periodic Table. Moreover, in the plane of the principal and orbital quantum numbers there is an obvious symmetry between the hydrogen-atom spectrum (one-electron problem) and the electronic configurations of all atoms (multi-electron problem). In order to explain these phenomena, it is hypothesized that between shell electrons and nuclei protons there exists a reversible quantum-field interaction (electron + proton ↔ neutron + neutrino resonance). Even if this interaction were a rare event, it can explain the existence of 4D symmetries mentioned above. However, the model considered here is based on frequent epn interactions, taking place more often than 1015 times per second. In this case, epn resonance and resonance between such resonances are supposed to underlie the structure of all atoms and molecules. In particular, the functioning of all biological molecules, including electron transfer and enzymatic activity, is determined by resonance, resonance between resonances, hierarchy of resonances, and networks of resonances. The text was submittred by the author in english.  相似文献   
6.
7.
A particulate enzyme preparation from Bacillus stearothermophilus synthesized 1,3-poly(glycerol phosphage) from CDPglycerol at an optimum pH of 8.0 and the reaction was stimulated by divalent cations. Km for CDPglycerol was 0.18 mM. The synthesis was inhibited by CMP, CDP, and CTP and by concentrations of CDP-glycerol above 0.49 mM. The reaction was irreversible, The product had an average chain length of 8 glycerol units. About two thirds of the polymers were synthesized in entirety while the ramainder were attached to some acceptor by their phosphate end. The enzome was able to synthesize only a limited amount of polymer.  相似文献   
8.
Y. Magarshak 《Bio Systems》1993,30(1-3):21-29
A quaternion representation of nucleotides is proposed, with representation of RNA sequences by vectors whose elements are quaternions. Structure and transition matrices in quaternion representation are defined. Correspondence between diagrammatic technique in complex-number and quaternion representation of nucleotides is delineated.  相似文献   
9.

Background  

Nitric oxide and prostaglandin E2 (PGE2play pivotal roles in both the pathogenesis of osteoarthritis and catabolic processes in articular cartilage. These mediators are influenced by both IL-1β and mechanical loading, and involve alterations in the inducible nitric oxide synthase (iNOS) and cyclo-oxygenase (COX)-2 enzymes. To identify the specific interactions that are activated by both types of stimuli, we examined the effects of dynamic compression on levels of expression of iNOS and COX-2 and involvement of the p38 mitogen-activated protein kinase (MAPK) pathway.  相似文献   
10.
The results of the determination of the level of antitoxic antibodies (Ab) to diphtheria and tetanus toxoids in children with glomerulonephritis and pyelonephritis are presented. The influence of the form of the disease and the kind of medicinal therapy on level of specific Ab has been studied. As shown in this study, the injection of adsorbed DT toxoid with reduced antigen content leads to the formation of the protective titers of antidiphtheria and antitetanus Ab, but a lower level than after the injection of adsorbed DPT vaccine.  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