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961.
962.
Lee  Raymond L. M. 《Dreaming》2010,20(4):288
Why are dreams easily forgotten or difficult to remember? Dream memory is usually attributed to stored fantasies and imaginations in sleep that have distant or no relevance to waking consciousness. Lack of dream recall suggests the modern emphasis on the significance of waking realities at the expense of oneiric experiences. Yet, in the ancient West and many contemporary non-Western societies, dreaming constitutes an unbroken chain of memory to the organization of everyday life. However, reenchantment in the modern context has given new importance to dream consciousness as vital to the development of the creative self. Emphasis on dream practices or dreamwork as leading to various forms of dream control suggests a quest for mastery of inner space. In this regard, training and motivation in dream recall provide an essential tool for advancing the self's well-being. Dreams are not treated as forgotten fantasies but dynamic pathways to new meanings of the self. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
963.
Water-protein interactions drive protein folding, stabilize the folded structure, and influence molecular recognition and catalysis. We analyzed the closest protein contacts of 10,837 water molecules in crystallographic structures to define a specific hydrophilicity scale reflecting specific rather than bulk solvent interactions. The tendencies of different atom and residue types to be the nearest protein neighbors of bound water molecules correlated with other hydrophobicity scales, verified the relevance of crystallographically determined water positions, and provided a direct experimental measure of water affinity in the context of the folded protein. This specific hydrophilicity was highly correlated with hydrogen-bonding capacity, and correlated better with experimental than computationally derived measures of partitioning between aqueous and organic phases. Atoms with related chemistry clustered with respect to the number of bound water molecules. Neutral and negatively charged oxygen atoms were the most hydrophilic, followed by positively-charged then neutral nitrogen atoms, followed by carbon and sulfur atoms. Agreement between observed side-chain specific hydrophilicity values and values derived from the atomic hydrophilicity scale showed that hydrophilicity values can be synthesized for different functional groups, such as unusual side or main chains, discontinuous epitopes, and drug molecules. Two methods of atomic hydrophilicity analysis provided a measure of complementarity in the interfaces of trypsin:pancreatic trypsin inhibitor and HIV protease:U-75875 inhibitor complexes. © 1995 Wiley-Liss, Inc.  相似文献   
964.
965.
Sewage sludge from the Upper Silesia Region of Poland were surveyed for keratinolytic fungi. Out of 100 Petri dishes examined, 89 were positive for these micro-organisms. Altogether, 185 fungal appearances belonging to 10 species were observed. Trichophyton terrestre with its teleomorph Arthroderma quadrifidum, T. ajelloi with A. uncinatum, Microsporum gypseum with Arthroderma sp., and Chrysosporium keratinophilum with Aphanoascus keratinophilus prevailed in the sludges. The sewage treatment technologies together with the sludge structure, humidity and pH were found to be critical factors determining the occurrence of keratinolytic fungi in the sludge environment. The qualitative and quantitative composition of keratinolytic fungi could be a useful tool in evaluation of sludge treatment processes.  相似文献   
966.
Summary The decision of whether or not to use QTLassociated markers in breeding programs needs further information about the magnitude of the additive and dominance effects that can be estimated. The objectives of this paper are (1) to apply some of the Moreno-Gonzalez (1993) genetic models to backcross simulation data generated by the Monte Carlo method, and (2) to get simulation information about the number of testing progenies and mapping density in relation to the magnitude of gene effect estimates. Results of the Monte Carlo study show that the stepwise regression analysis was able to detect relatively small additive and dominance effects when the QTL are independently segregating. When testing selfed families derived from backcross individuals, dominance effects had a larger error standard deviation and were estimated at a lower frequency. Linked QTL require a higher marker mapping density on the genome and a larger number of progenies to detect small genetic effects. Reduction of the environmental error variance by evaluating selfed backcross families in replicate experiments increased the power of the test. Expressions of the number of progenies for detecting significant additive effects were developed for some genetic situations. The ratio of the within-backcross genetic variance to the square of a gene effect estimate is a function of the number of progenies, the heritability of the trait, the marker map density and the portion of the genetic variance explained by the model. Different values (from 0 to 1) assigned to (relative position of the QTL in the marker segment) did not cause a large shift in the residual mean square of the model.  相似文献   
967.
IntroductionThe relationship between demographic and biochemical characteristics, including several established coronary risk factors, and serum copper and zinc was assessed in a large Iranian population sample.Materials and methodsA group of 2233 individuals, 15–65 years of age [1106 (49.5%) males and 1127 (50.5%) females] was recruited from residents of the Greater Khorasan province in northeast of Iran. Demographic data were collected using questionnaires. Coronary risk factors were determined using standard protocols, and trace elements were measured in serum using atomic absorption spectroscopy.ResultsDegree of glucose tolerance and smoking habit were not associated with serum zinc and copper levels. Serum copper levels were significantly higher in obese and hypertensive than in normal subjects (p<0.001). In the whole group and for the female subgroup, serum zinc (p<0.01) and copper (p<0.001) were both significantly lower in individuals with normal versus high levels of low-density lipoprotein cholesterol.A strong positive correlation was found between serum copper and body mass index (BMI) (r=0.85, p<0.001). Weaker positive associations were found between serum copper and calculated 10 years’ coronary risk (r=0.11, p<0.001). Serum zinc/copper ratio was strongly inversely associated with calculated 10 years’ coronary risk (r=?0.10, p<0.001). The partial Eta squared (PES) values for factors determining serum zinc were hypertension (0.007, p=0.01) and BMI (0.004, p=0.01); and for serum copper, they were gender (0.02, p=0.001), hypertension (0.004, p=0.009), and 10 years’ coronary risk for men (0.003, p=0.03) and women (0.002, p=0.07).ConclusionSignificant associations between serum trace element concentrations and several coronary risk factors, including calculated 10 years’ coronary risk scores, were found.  相似文献   
968.
Development of first instar larvae of Gonia cinerascens, which rest in the muscles of host caterpillars, is triggered by the release of the host's ecdysteroids when the juvenile hormone is absent. Ecdysteroids act on the parasitoid directly and at the same time induce physiological and biochemical changes in the host, which are indispensable for the parasitoid's development. These changes do not occur when metamorphosis of the host is suppressed with the juvenile hormone. Normally the parasitoids initiate development at the larval-pupal transformation of the host, but under experimental conditions, they do so whenever a high ecdysteroid titre is coupled with the proper internal environment in the host, that is in decapitated caterpillars, isolated host abdomens, and when implanted into host pupae. Activated parasitoids moult into the second instar and migrate to the exuvial space of the host; this migratory behaviour is also triggered by ecdysteroids and may be induced experimentally in the first instar parasitoids. Unknown clues direct the migrating parasitoids under the wings and appendages of the host pharate pupal stage. The second instar parasitoids, which anchor to the integument of the host pupae, apparently develop independently of the host's hormones: they can produce third instar larvae, pupae, and adult flies when cultured in vitro.  相似文献   
969.
This is the first comprehensive analysis of vascular plant diversity patterns in the Aleutian Islands to identify and quantify the impact of Aleutian Island distance dispersal barriers, geographical, ecological and anthropogenic factors. Data from public Open Access databases, printed floristic accounts, and from collections made by the primary author were used to develop an Aleutian floristic database. The most common plant distribution pattern was “an eastern origin community”, though it compared similarly to the “Western” and “Widespread” distribution pattern. We established an ecological plant community composition class for each island, based on clustering species assemblage dissimilarity measurements (Jaccard Index), and a measurement of phylogenetic dissimilarity (UniFrac). We modelled these composition classes and species richness values in non‐parametric algorithmic models and concepts (data cloning using machine learning, stochastic boosting‐ TreeNet) based on classic and Aleutians‐specific island biogeography hypotheses. Plant species richness is strongly associated with the equilibrium model variables of area and island isolation, as well as distance to the Alaska Peninsula, and island total stream length. Species composition is strongly associated with the landmass groups during the last glacial maximum, maximum island elevation, island isolation and island area. Phylogenetic composition is associated with island area, distance from the islands to the Chukotka Peninsula, maximum island elevation, island geologic age, and island isolation. This study extends the equilibrium theory of island biogeography by including additional drivers of diversity during the Anthropocene, such as the landmass during the LGM, as well as factors that may be related to anthropogenic extinction rate.  相似文献   
970.
植物叶片衰老机理的几种假说   总被引:28,自引:0,他引:28  
关于植物叶片衰老已有很多工作,对于衰老的机理提出了许多假说。本文汇总、介绍了其中几种主要假说。  相似文献   
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