共查询到20条相似文献,搜索用时 15 毫秒
1.
A method of informational decomposition has been developed, allowing one to reveal hidden periodicity in any symbol sequence. The informational decomposition is calculated without conversion of a symbol sequence into a numerical one, which facilitates finding periodicities in a symbol sequence. The method permits introducing an analog of the autocorrelation function of a symbol sequence. The method developed by us has been applied to reveal hidden periodicities in nucleotide and amino acid sequences, as well as in different poetical texts. Hidden periodicity has been detected in various genes, testifying to their quantum structure. The functional and structural role of hidden periodicity is discussed. 相似文献
2.
Method of informational decomposition has been developed, allowing one to reveal hidden periodicity in any symbol sequences. The informational decomposition is calculated without conversion of a symbol sequence into the numerical one, which facilitates finding periodicities in a symbol sequence. The method permits introducing an analog of the autocorrelation function of a symbol sequence. The method developed by us has been applied to reveal hidden periodicities in nucleotide and amino acid sequences, as well as in different poetical texts. Hidden periodicity has been detected in various genes, testifying to their quantum structure. The functional and structural role of hidden periodicity is discussed. 相似文献
3.
Memory problems are the most common cognitive deficits in dementia. In order to help these patients with their everyday activities and to increase their quality of life, a number of memory aids have been developed. This paper focuses on the efficacy and the applicability of three different types of external memory aids. The findings suggest that environmental adjustment is an easy and low-priced method. It is beneficial even for patients in the most severe stages of dementia, since only a limited amount of training is necessary. The non-electronic aids are also relatively cheap and easy to learn. The electronic aids are more expensive and, at this point, only a few studies have investigated the efficacy of this memory aid on the memory problems of patients with dementia. However, most published studies only investigated small samples. Hence, the current results should be interpreted with caution. 相似文献
4.
William T. Duggan 《The Western journal of medicine》1949,70(3):198-201
Recently the problems of the hard-of-hearing have been receiving more attention. Laboratories for proper treatment and diagnosis are being developed. The Army and Navy rehabilitation centers have made great strides in the advancement of the problems of selecting hearing aids and training in their use. Hearing aids have improved greatly since the advent of the midget vacuum tube. Newer and better models are continually being produced. Fitting of aids to an audiogram is not practical as yet. Bone conduction oscillators are inefficient and seldom indicated. The conduction type of hearing impairment does not usually present much of a problem as far as selection of an aid is concerned.Anyone who has difficulty in hearing ordinary conversation should think seriously of wearing an aid. 相似文献
5.
艾滋病是全球流行的一种严重传染病,严重损害机体免疫系统,病死率高,至今仍无治愈手段。该病以破环细胞免疫功能为主,因此,认识疾病病程的免疫状态对于进一步探索治疗艾滋病的方法意义重大。CD4+CD25+调节性T细胞在感染性疾病、移植耐受、自身免疫等疾病中的免疫作用是近年来研究热点。在艾滋病中,CD4+CD25+调节性T细胞发挥着重要的免疫作用,研究在不同疾病阶段该细胞亚群所起作用将有助于我们揭示疾病免疫机制。本文概述了CD4+CD25+调节性T细胞频率与艾滋病疾病进展的关系。 相似文献
6.
Prolonged immobilization results in several physiological problems. It has been demonstrated that standing exercises can ameliorate many of these problems. Standing exercises can be performed efficiently with the help of functional electrical stimulation (FES). A novel robotic mechanism which aids the unsupported standing of paraplegics, providing balancing exercise has been developed. The balancing strategy is based on voluntary activity of the paraplegic's upper body and artificially controlled stiffness in the ankles. 相似文献
7.
Fundamental research in enzymology have remarkably developed during the past thirty years. However, the actual application of enzymes has been rather limited for several technical and economical reasons. Such limiting factors are now being overcome year after year. Immobilized enzyme and cell technology might be a kind of break-through in this field. From the industrial view-point, enzyme technology is now coming into its real developmental stage. Enzyme technology has recently been finding several directions for its development. These directions may be classified as follows : (1) new industrial catalysts, (2) Tools for food production and processing, (3) pharmaceutical uses, (4) analytical and measurement tools, (5) aids for screening new physiologically active substances, and (6) aids for creation of new sources of energy and raw materials. The authors wish to demonstrate such directions of enzyme technology using actual examples studied and/or operated mainly in Japan. 相似文献
8.
DUISENBERG CE 《California medicine》1949,70(3):182-188
A rapid cassette changer developed at Stanford University Hospital has been successfully used to record, radiographically, swift vascular flow and intrinsic motion of other hollow organs. This aids diagnosis of disease and study of normal physiologic motion. 相似文献
9.
Charles E. Duisenberg 《The Western journal of medicine》1949,70(3):182-188
A rapid cassette changer developed at Stanford University Hospital has been successfully used to record, radiographically, swift vascular flow and intrinsic motion of other hollow organs. This aids diagnosis of disease and study of normal physiologic motion. 相似文献
10.
Latent Periodicity of Serine/Threonine and Tyrosine Protein Kinases and Other Protein Families 总被引:1,自引:0,他引:1
A method of noise decomposition has been developed. This method allows for the identification of a latent periodicity with symbol insertions and deletions that is specific for all or most amino acid sequences belonging to the same protein family or protein domain. The latent periodicity has been identified in catalytic domains of 85% of serine/threonine and tyrosine protein kinases. Similar results have been obtained for 22 other protein families. The possible role of latent periodicity in protein families is discussed.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 3, 2005, pp. 420–436.Original Russian Text Copyright © 2005 by Laskin, Kudryashov, Skryabin, Korotkov. 相似文献
11.
A computer assisted method for the determination of restriction enzyme recognifion sites. 总被引:13,自引:10,他引:3
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A computer program has been developed which aids in the determination of restriction enzyme recognition sequences. This is achieved by cleaving DNAs of known sequence with a restriction endonuclease and comparing the fragmentation pattern with a computer-generated set of patterns. The feasibility of this approach has been tested using fragmentation patterns of 0X174 DNA produced by enzymes of both known and unknown specificity. Recognition sequences are predicted for two restriction endonucleases (BbvI and SfaNI) using this method. In addition, recognition sequences are predicted for two other new enzymes (PvuI and MstI) using another computer-assisted method. 相似文献
12.
Kornakova EE 《Parazitologiia》2002,36(2):96-107
Ultrastructure of the epithelium of adult and juvenile Urastoma cyprinae has been studied. The epithelium of both adult and juvenile worms is cellular, ciliated and bears numerous microvilli. The cytoplasm is rich in large, numerous epitheliosomes of two types--electron-dense and with fibrillated content (fig. 1, a, [symbol: see text]; 2, a-[symbol: see text]). Besides large secrete granules small membrane-bounded vesicles were observed (fig. 2, a-[symbol: see text]). In juvenile worms the dense epitheliosomes are less abundant and the fibrillated content in the second type of granules has a different structure: the fibrils are very thin and more densely packed forming the structures of the less electron density (fig. 3, a, [symbol: see text], [symbol: see text] 1). The membrane-bounded vesicles in the epithelium of juvenile worms were not observed. All types of secrete are ejected by exocytosis (fig. 2, [symbol: see text]; 3, [symbol: see text], [symbol: see text]). The ultrastructure of the epithelium in juvenile U. cyprinae is strongly similar to that in parasitic turbellarian Kronborgia, especially to the epithelium in a male and a larva. The basal lamina consists of tree layers and forms numerous deep infoldings into the epithelium (fig. 1, a; 2, a; 3, a, [symbol: see text], [symbol: see text]). The basement membrane projects deep and numerous invaginations into the epithelium which may almost reach the apical membrane (fig. 1, a; 2, a, [symbol: see text], [symbol: see text]; 3, [symbol: see text]). Mitochondria are large and situated mainly near the projections of the basement membrane (fig. 2, [symbol: see text]-[symbol: see text]; 3, [symbol: see text]). Such ultrastructure implies an intensive process of the transmembrane transfer of the dissolved organic substances from the sea water. The same structures were found in the epithelium of Kronborgia. Uptake of organic compounds through the epithelium in the common ancestors of Urastoma and Kronborgia could be the preadaptation to the endoparasitic mode of life in Fecampiida. The differencies in ultrastructure of epithelium in U. cyprinae from the White Sea and from Mediterranean Sea (Noury-Sra?ri e. a., 1990) may be explained by the differences in the method of fixation or by the parasitizing the another host--the mollusk Mytilus galloprovincialis. The ciliary receptors of five types were revealed in U. cyprinae (fig. 3, e, [symbol: see text]; 4; 5; 6). They differ in the shape and length of the ciliary rootlets and in the content of the nerve processes. All receptors lack of the real collars typical for the receptors of Neodermata. Urastoma is most close to the Neodermata amond parasitic turbellarians studied thus far, and the absence of collars in receptors of this species testifies that the collars are the veritable synapomorphy of the Neodermata. The diversity in the ultrastructure and possible functions of receptors correspond to the complicated adaptations of this species. The modern molecular data as well as the ultrastructural evidence attest that parasitic turbellarians of the genera Urastoma, Genostoma and Ichthyophaga are relatives and cannot be included in any turbellarian order known. Therefore Urastoma, Genostoma and Ichthyophaga have been erected in the separate order Urastomida ord. nov. The diagnosis of the new order is given. 相似文献
13.
Ramazzotti M Degl'Innocenti D Manao G Ramponi G 《The Italian journal of biochemistry》2004,53(1):16-22
Amino acid sequence alignment is an extremely useful tool in protein family analysis. Most family characteristics, such as the localization of functional residues, structural constraints and evolutionary relationships may be retrieved through the observation of the conservation pattern highlighted by the alignments. A quantitative score for the conservation in the alignment allows different stages of an alignment to be compared and consequently the alignment information to be efficiently exploited. Many scoring methods have been proposed during the last three decades. Claude Shannon's theory of communication (1948) paved the way for a consistent scoring of protein alignments by considering the residue (or symbol) frequency. A number of modifications have been proposed since that time, but the core statistical approach is still considered one of the best. By combining many database managing tools for treatment of protein sequences, a ClustalW software integration, a flexible symbols treatment and gap normalization functions, Entropy Calculator software has been developed. This new tool provides a global and optimal approach to multiple sequence alignment scoring by offering an easy graphic interface and a series of modification options that help in interpreting alignments and allow conservation pattern inferences to be performed. 相似文献
14.
Melford E. Spiro 《American anthropologist》1979,81(1):5-13
There has been a strong tendency in structural and symbolic anthropology to assume that sex and aggression are of no concern to cultural symbol systems. Even when cultural beliefs, myths, or rituals are explicitly and preponderantly sexual or aggressive in content, they are typically interpreted as metaphors for social structural themes. This thesis is illustrated with respect to aggression by an analysis of Lévi-Strauss' interpretation of a Bororo myth, after which the assumptions that structural theory makes concerning the place of aggression in cultural symbol systems are contrasted with the opposing assumptions of psychoanalytic theory. [structuralism, psychoanalysis, cultural symbol systems, myth] 相似文献
15.
In a previous project, we screened the American mink Bacterial Artificial Chromosome library, CHORI‐231, for genes potentially involved in various coat colour phenotypes in the American mink. Subsequently, we 454 sequenced the inserts containing these genes and developed microsatellite markers for each of these genes. Here, we describe a lack of association between three different ‘roan‐type' phenotypes represented by Cross, Stardust and Cinnamon in American mink and six different genes that we considered to be potentially linked to these phenotypes. Thus, c‐KIT (HUGO‐approved symbol KIT), ATOH‐1 (HUGO‐approved symbol ATOH1) and POMC were excluded as potential candidates for these three phenotypes. In addition, MITF and SLC24A5 were excluded for Cross and Cinnamon, and KITL (HUGO‐approved symbol KITLG) for Cross and Stardust. Although most of these genes have been implicated as the cause of similar phenotypes in other mammals, including horses, pigs, cows, dogs, cats, mice and humans, they do not appear to be responsible for comparable phenotypes found in American mink. 相似文献
16.
A method has been developed for constructing a tree source model for genetic text generation. Model visualisation in the form of suffix (context) trees provides a new way of context analysis of symbol sequences. Estimation of the stochastic complexity of the data in the frame of the model serves as a criterion for the model's ascertainment. The model and complexity values are used for analysis of genetic texts. The software realisation of this algorithm enables to reveal statistical properties of genetic sequences based on an information measure. The program developed is available via Internet at http://wwwmgs.bionet.nsc.ru/mgs/programs/complexity/. 相似文献
17.
Goldsworthy R Kaplan B 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(6):453-460
BACKGROUND: Previous research has noted potential inadequacies in the warning labels and symbols used with some teratogenic medications. A clear teratogen warning symbol represents an important component of risk mitigation for accidental teratogen exposure. METHODS: Several teratogen warning symbols were developed through rapid prototyping and focus groups. A nationally distributed field trial (n = 300) examined the relative effectiveness of 6 candidate symbols, including the symbol in use at the time of the study. Measures included open-ended interpretation, closed-ended preference, and demographic surveys. Each participant was shown a single symbol and asked what it meant, to whom it applied, and what that person should do. Text statements were added to the symbol and participants were asked to reinterpret the warning. Participants were told the intended message of the warning, shown all 6 symbols, and asked to choose the most effective symbol. RESULTS: Four of 6 symbols achieved levels of correct interpretation close to or exceeding the American National Standards Institute (ANSI) benchmark of 85% and none exceeded the ANSI limit of 5% critical confusion. Symbols elicited varying conceptual responses. Respondents considered 1 symbol to be the most effective, by a 4 to 1 margin. Several outcomes varied by age and by ethnicity. CONCLUSIONS: Several symbols emerged as viable alternatives to the current symbol; however, no 1 symbol was clearly found to be the most effective. Instead, the symbol considered "best" depends on the messages that are considered most essential to the warning. Additionally, it appears a symbol without the addition of text can convey most, but possibly not all, of the meaning required of the warning label. Next steps should include further symbol refinement, closer examination of text additions to symbols, and validation of the candidate symbols and warnings through a large-scale field trial. 相似文献
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植被图通常采用不同的颜色并结合符号来区分不同的植被类型, 以期更加直观、清晰地将植被类型信息传达给读者。如何通过色彩和符号的合理搭配来区分不同的植被类型是植被制图中的关键步骤, 尤其是对于植被类型较丰富的区域, 植被图的色彩和符号设计更为复杂。植被图图例系统建立在植被分类系统之上, 近10余年来我国的植被分类系统得到了进一步的发展和完善, 因此, 非常有必要在最新的植被分类系统基础上, 提出一套植被制图色彩和符号设计方案, 用以指导当前的植被制图工作。该研究整理了地图学、植被图以及其他专题地图色彩和符号设计的要求, 提出了植被制图的色彩和符号设计原则。在最新的植被分类系统基础上, 采用颜色三属性(色调、明度、饱和度)及符号的基本视觉变量(形状、尺寸、方向、色彩、密度、亮度)的变化及其组合, 依据色彩和符号设计的系统性、科学性、象征性等原则, 对中国植被分类系统高级分类单位中的植被亚型, 进行了标准化配色和符号设计, 旨在为植被制图工作者及新一代1:50万植被图编研提供理论依据和参考, 提升植被制图的效率和质量。 相似文献
20.
That smooth muscles dilate and contract rhythmically has been known for a long time and the phenomenon has been studied for nearly as long. However, the causes and effects of smooth muscle oscillation (termed vasomotion) are far from clear. It is thought that vasomotion aids the delivery of oxygen to tissues surrounding capillary beds. On the other hand, unregulated vasomotion might participate in the development and maintenance of pathophysiological states. Nilsson and Aalkjaer review what is known about vasomotion and its consequences. 相似文献