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1.
The dissimilarities between 107 British plant families with respect to the insect and mite species which feed on them were analysed using a principal co-ordinates analysis. The relationships between the plant families were strongly influenced by the plant life forms. Major groups were woody plants (trees and shrubs), aquatic plants and herbs. A wet to dry gradient was distinguished, as were evergreen plants, and early successional plant families with weeds and annuals. Taxonomically, plant families of the same order were closer together if they were predominantly of the same life form. Fagales and several orders of monocotyledons formed particularly clear groups. The three 'nearest neighbours' of each plant family based on the dissimilarities measures were listed. These provide some interesting, but conjectural, data on evolutionary aspects of plant families. This was illustrated briefly by the Cornaceae and Euphorbiaceae. The underlying progressive evolution of plants from woody species and wetter areas to herbs and annual plants of dry and cold places may be reflected by insect and mite food plant family associations.  相似文献   

2.
目的:探讨术前心理准备对肺癌患者胸腔镜术后生存质量的影响。方法:随机将100例胸腔镜肺叶切除术加淋巴结清扫术后肺癌患者分为两组,实验组患者及其家属术前接受行腔镜手术的健康教育与宣讲,并观看相应手术视频和手术室及监护室环境的图片,对照组患者及其家属术前只接受传统的的口头和文字叙述为主的术前宣教方式。采用欧洲癌症治疗与研究组织癌症生存量表核心量表(QLQ-C30)中文版评估和比较两组患者术前及术后1、3、6和12个月的生活质量。结果:1)术后12个月,实验组的角色、情绪和认知评分明显高于对照组,有统计学差异(P0.05);2)术后1个月,实验组的疲劳、疼痛和呼吸困难评分明显低于对照组,有统计学差异(P0.05)。结论:术前视觉化的护理干预可明显提高肺癌患者胸腔镜术后的生存质量。  相似文献   

3.
Despite evidence of the importance of value similarity in predicting parent-adult child relations, little attention has been given to the unique role of religious similarity. Using 1,407 dyads nested within 390 families, we examine whether religious similarity predicts the quality of mother-child relations in later life, and whether the strength of this association differs by race. Consistent with our hypotheses, religious similarity was found to be an important factor in predicting both closeness and conflict, particularly in Black families. These findings suggest that it may be important to give greater attention to religion when studying patterns of interaction and support in the later years, especially among Black families.  相似文献   

4.
5.
New directions in biology are being driven by the complete sequencing of genomes, which has given us the protein repertoires of diverse organisms from all kingdoms of life. In tandem with this accumulation of sequence data, worldwide structural genomics initiatives, advanced by the development of improved technologies in X-ray crystallography and NMR, are expanding our knowledge of structural families and increasing our fold libraries. Methods for detecting remote sequence similarities have also been made more sensitive and this means that we can map domains from these structural families onto genome sequences to understand how these families are distributed throughout the genomes and reveal how they might influence the functional repertoires and biological complexities of the organisms. We have used robust protocols to assign sequences from completed genomes to domain structures in the CATH database, allowing up to 60% of domain sequences in these genomes, depending on the organism, to be assigned to a domain family of known structure. Analysis of the distribution of these families throughout bacterial genomes identified more than 300 universal families, some of which had expanded significantly in proportion to genome size. These highly expanded families are primarily involved in metabolism and regulation and appear to make major contributions to the functional repertoire and complexity of bacterial organisms. When comparisons are made across all kingdoms of life, we find a smaller set of universal domain families (approx. 140), of which families involved in protein biosynthesis are the largest conserved component. Analysis of the behaviour of other families reveals that some (e.g. those involved in metabolism, regulation) have remained highly innovative during evolution, making it harder to trace their evolutionary ancestry. Structural analyses of metabolic families provide some insights into the mechanisms of functional innovation, which include changes in domain partnerships and significant structural embellishments leading to modulation of active sites and protein interactions.  相似文献   

6.
A Brack  G Spach 《Bio Systems》1987,20(1):95-98
One of the main characteristics of terrestrial life is the role of optically active organic substances. Thus a search for chiral compounds and optical activity on an extraterrestrial body may give an indication of the presence of life, either fossilized or still in existence. If only abiotic conditions are prevailing the same search may still provide interesting information on the possible origins of homochiral families of biomolecules on Earth (e.g. the amino acids). In this respect, Saturn's satellite Titan is exemplary. A list of some of the most simple chiral derivatives devoid of oxygen atoms possibly present on Titan is presented. The interest of an investigation of optical activity is discussed taking into account some significant parameters. This raises numerous difficult technical problems which once solved may be helpful for further exploration of other planets.  相似文献   

7.
There has been among family therapists a widespread belief that anthropology is at least useful if not kindred to their field. The belief springs from the assumption that families in different cultural milieus have different ways of expressing their experience of intimacy in everyday life. If this is true, family organization transcends culture, and the latter is a mere language or mode of expression of the more basic pillar of family organization. However, the assumption is also strong that different cultural contexts produce different types of families, and the natural consequence of this hypothesis is that family therapy as developed in the United States would be restricted to dealing with American families, while the problems of family life elsewhere should be meted by the local cultural ways. These two hypotheses, namely that of family universality and that of cultural relativism, are far ends of a continuum. The more interesting and real cases lie somewhere in the middle.In the following argument I will discuss this subject by presenting a brief overview of family therapy's theories and practices for those readers who know nothing about it, by reviewing a recent book that makes the claim that family therapists will benefit from some kind of anthropological knowledge, and finally by turning the question on its head and addressing the interest family therapy may have for anthropologists.  相似文献   

8.
目的:探讨同步实施家属健康教育对甲状腺癌手术患者生活质量的影响,为改善甲状腺癌手术患者的生活质量提供可能的途径。方法:选择78例甲状腺癌手术患者及其家属作为研究对象,并将其随机分为对照组和干预组,每组39例,对照组给予常规治疗、护理及健康教育;干预组在接受常规治疗、护理及健康教育的同时,同步对其家属实施健康教育。分别于健康教育干预前、干预1个月、6个月后采用生活质量问卷(QL-Index)及抑郁自评量表(SDS)评价和比较两组患者的生活质量评分和抑郁症状评分。结果:健康教育干预1个月、6个月后,干预组的角色功能、社会功能、情绪功能、总体生活质量得分均显著高于干预前(P<0.05),且高于同时点的对照组(P<0.05);干预组的抑郁症状评分均显著低于干预前(P<0.05),且明显低于同时点的对照组(P<0.05)。结论:同步实施家属健康教育可以显著提高甲状腺癌手术患者的生活质量,并降低患者的抑郁水平。  相似文献   

9.
Why do some avian families contain so many more species than other families? We use comparisons between sister taxa to test predictions arising from six explanations to this puzzle: that differences between families are due to chance, body size, life history, sexual selection, intrinsic ecological factors or extrinsic abiotic factors, respectively. In agreement with previous analyses, we find no support for the idea that differences in species richness are simply due to chance. However, contrary to most previous work, we also find no support for the hypotheses that high species richness is correlated with small body size and fast life history. Rather, high species diversity is strongly associated with pronounced plumage dichromatism, generalist feeding habits and good dispersal capabilities as well as large and fragmented geographical ranges. In addition, all of these relationships are robust to the removal of the two most speciose avian lineages, the Ciconiiformes and the Passeriformes. The supposed relationships between species richness and both body size and life history are, however, due to phylogenetic non-independence. Together with previous work showing that differences between avian lineages in extinction risk are associated with variation in body size and life history, these results indicate that extinction rates and speciation rates are not necessarily determined by the same factors. Hence, high extinction rates are not inevitably associated with low speciation rates. Extinction-prone lineages may, in fact, have a high rate of speciation. In such lineages a high proportion of ''vulnerable'' species would be a natural, ongoing phenomenon.  相似文献   

10.
There are at least 86 species of troglomorphic fishes belonging to 18 families. Some of those families are characterized by features that can be labeled as preadaptations to the hypogean life; others are not. The level of structural reduction in eye development and pigmentation is highly variable, even within some populations. Reduction in number and complexity of scales does occur but has yet to be fully documented. Reduction in the size and structure of the swim(gas)bladder may be another troglomorphic feature. There is considerable doubt on the taxonomic position of many species of troglomorphic fishes given that a number of them have been described solely on the basis of morphology while genetically they may be very closely correlated to genera different from those they have been assigned to. Geographically speaking there are no evident patterns since many of those species are not found in karstic areas but in phreatic waters. These fishes represent an excellent example of convergent evolution.  相似文献   

11.
Herbivory has many effects on plants, ranging from shifts in primary processes such as photosynthesis, growth, and phenology to effects on defense against subsequent herbivores and other species interactions. In this study, I investigated the effects of herbivory on seed and seedling characteristics of several families of wild radish (Raphanus raphanistrum) to test the hypothesis that herbivory may affect the quality of offspring and the resistance of offspring to plant parasites. Transgenerational effects of herbivory may represent adaptive maternal effects or factors that constrain or amplify natural selection on progeny. Caterpillar (Pieris rapae) herbivory to greenhouse-grown plants caused plants in some families to produce smaller seeds and those in other families to produce larger seeds compared with undamaged controls. Seed mass was positively associated with probability of emergence in the field. The number of setose trichomes, a putative plant defense, was higher in the progeny of damaged plants in some families and lower in the progeny of damaged plants in other families. In a field experiment, plant families varied in their resistance to several herbivores and pathogens as well as in growth rate and time to flowering. Seeds from damaged parent plants were more likely to become infested with a plant virus. Although herbivory on maternal plants did not directly affect interactions of offspring with other plant parasites, seed mass influenced plant resistance to several attackers. Thus, herbivory affected seed characters, which mediated interactions between plants and their parasites. Finally, irrespective of seed mass, herbivory on maternal plants influenced components of progeny fitness, which was dependent on plant family. Natural selection may act on plant responses to herbivory that affect seedling-parasite interactions and, ultimately, fitness.  相似文献   

12.
Most studies of the association between family structure and risky sexual behaviour among adolescents and young adults have employed a risk perspective which assumes that, compared with other types, two-parent families are protective. Drawing from a positive-oriented approach in this study, it is hypothesized that within each family type some influential factors may mitigate such anticipated deleterious effects of non-intact families and decrease sexual risk-taking. The paper examines specifically the effects of risk and protective factors with an emphasis on family processes associated with resilience, using data from a pooled sample of 1025 females and males aged 12-24 years from Bandjoun (West Cameroon). Findings show that the quality of parent/guardian-youth relationships significantly decreases the odds of risky sexual behaviour by 36%, 65% and 50% in neither-, one- and two-parent families, respectively. For two-parent families only, parental control acts as a significant protective factor; it decreased by 41% the odds of risky sexual behaviour. Programmatically, protective family factors such as parent/guardian-youth interactions need to be promoted to improve the efficiency of reproductive health and HIV interventions in sub-Saharan Africa.  相似文献   

13.
The purpose of this paper is to show some aspects of music therapy application in cancer care and to present the integration of music therapy program into a continuous supportive cancer care for inpatients. A cancer diagnosis is one of the most feared and serious life events that causes stress in individuals and families. Cancer disrupts social, physical and emotional well-being and results in a range of emotions, including anger, fear, sadness, guilt, embarrassment and shame. Music therapy is a part of a complementary medicine program in supportive cancer care which accompanies medical treatment. There are many benefits of music therapy for cancer patients—interactive music therapy techniques (instrumental improvisation, singing) as well as receptive music therapy techniques (listening to recorded or live music, music and imaginary) can be used to improve mood, decrease stress, pain, anxiety level and enhance relaxation. Music therapy is an effective form of supporting cancer care for patients during the treatment process. It may be also basic for planning effective programs of rehabilitation to promote wellness, improve physical and emotional well-being and the quality of life.  相似文献   

14.
Type II DNA topoisomerases (Topo II) are essential enzymes implicated in key nuclear processes. The recent discovery of a novel kind of Topo II (DNA topoisomerase VI) in Archaea led to a division of these enzymes into two non-homologous families, (Topo IIA and Topo IIB) and to the identification of the eukaryotic protein that initiates meiotic recombination, Spo11. In the present report, we have updated the distribution of all Topo II in the three domains of life by a phylogenomic approach. Both families exhibit an atypical distribution by comparison with other informational proteins, with predominance of Topo IIA in Bacteria, Eukarya and viruses, and Topo IIB in Archaea. However, plants and some Archaea contain Topo II from both families. We confront this atypical distribution with current hypotheses on the evolution of the three domains of life and origin of DNA genomes.  相似文献   

15.
An ability to tolerate airborne saltwater spray is critical for plant populations in coastal environments. The opportunity for continued microevolution for improved salt tolerance can exist if there is variation in the response of genetic families to saltwater spray. Our objective was to determine whether or not there was differentiation among subpopulations near (15 m) and far (80 m) from shore and among families within subpopulations in relation to the effects of salt spray on life history traits in a population of the dunegrass Triplasis purpurea. In this annual, most seeds are matured in cleistogamous spikelets on axillary, leaf-sheath enclosed panicles and show poor dispersal capacity. Plants were reared in the greenhouse from seeds of 13 and 11 families from the near and far subpopulations, respectively. Fifty percent of plants in a family were subjected to 6 seawater sprays/wk, resulting in weekly salt deposition of 213 μg/cm(2); the others were sprayed with distilled water. Data were recorded on life span, tiller numbers, root and shoot dry mass, and seed production. There was no effect of subpopulation on any measured trait and, hence, no evidence for local adaptation to salt spray. Final tiller numbers, but not dry mass or seed production, were reduced by salt spray. However, for most traits there were significant family (within subpopulation) effects, indicating genetic substructuring. Life span and mean seed mass showed a significant family by treatment interaction, indicating genetic variation in phenotypic responses to salt spray. Life span and mean seed mass were reduced by salt spray in some, but not all, families. Path analysis revealed that an increase in life span or tiller number indirectly increased seed production via direct effects on vegetative mass. For this relatively salt-tolerant T. purpurea population on the south shore of Staten Island, New York, USA, salt sprays may not be a significant agent of natural selection. However, there are pronounced phenotypic differences among inbred family groups and opportunity for genetic substructuring within these subpopulations. Variable effects of salt spray among families could result in microevolutionary changes in life span and mean seed mass, both of which impact annual fitness in this dunegrass.  相似文献   

16.
Abstract. Within many phylogenetic assemblages, a pattern of domination has been observed: one or a few clades have had many more speciation events or fewer extinctions than other clades in a particular assemblage. We investigated this phenomenon in the polychaete annelids. Polychaetes comprise ∼9000 described species classified in over 70 families and exhibit a great variety of life history strategies. Our goal was to test whether diverse polychaete families are characterized by species with short generation times, high reproductive output, small body size, or with planktotrophic larval development. Each of these factors has been advanced as cause for high diversity in other taxonomic assemblages. Here, we establish that the diversification pattern of polychaete families is non-random, but the data collected show no significant correlations between familial diversity and several life history traits including age at first reproduction, life span, body size, fecundity, and egg size. Pairwise comparisons of sister families do not reveal any trends between familial diversity and any of the life history traits. The great variability of life history traits within polychaete families may explain the lack of significant results; perhaps no trends are seen because polychaete life history traits cannot be generalized at the family level.  相似文献   

17.
Background Halophytes are rare, with only 0·25 % of angiosperm species able to complete their life cycle in saline conditions. This could be interpreted as evidence that salt tolerance is difficult to evolve. However, consideration of the phylogenetic distribution of halophytes paints a different picture: salt tolerance has evolved independently in many different lineages, and halophytes are widely distributed across angiosperm families. In this Viewpoint, I will consider what phylogenetic analysis of halophytes can tell us about the macroevolution of salt tolerance.Hypothesis Phylogenetic analyses of salt tolerance have shown contrasting patterns in different families. In some families, such as chenopods, salt tolerance evolved early in the lineage and has been retained in many lineages. But in other families, including grasses, there have been a surprisingly large number of independent origins of salt tolerance, most of which are relatively recent and result in only one or a few salt-tolerant species. This pattern of many recent origins implies either a high transition rate (salt tolerance is gained and lost often) or a high extinction rate (salt-tolerant lineages do not tend to persist over macroevolutionary timescales). While salt tolerance can evolve in a wide range of genetic backgrounds, some lineages are more likely to produce halophytes than others. This may be due to enabling traits that act as stepping stones to developing salt tolerance. The ability to tolerate environmental salt may increase tolerance of other stresses or vice versa.Conclusions Phylogenetic analyses suggest that enabling traits and cross-tolerances may make some lineages more likely to adapt to increasing salinization, a finding that may prove useful in assessing the probable impact of rapid environmental change on vegetation communities, and in selecting taxa to develop for use in landscape rehabilitation and agriculture.  相似文献   

18.
The warming climate has enabled a rapid expansion of many forest pests. The adaptation potential of the invaders affects largely on how well the invasive species can spread to new areas and in what extent can they have an impact on the invaded ecosystem. To measure the adaptation potential of an invasive (winter moth) and a potentially invasive defoliating moth species (scarce umber moth), we examined life history parameters in two environments on a set of genetically diverse host trees and compared the traits with those of a resident moth species (autumnal moth). In addition, variations in life history parameters due to host genotype were calculated and compared. The bioassay was executed by rearing moth larvae on 11 half‐sib families of the host tree in two large tree line gardens. The use of half‐sib families allowed us to calculate the variances due to tree genotype and also to examine if the new arrivals can affect the selection pressure on the genetic population structure of the host. According to our results, the natural genetic variation in host plant quality and small environmental differences are not sufficiently effective to restrict the spread of the already established invasive species. The invading moth species may even be better at adapting to variation in food quality than the resident moth species. The overall effect of the natural variation in tree quality was similar for all three moth species. Therefore, the newcomers are likely to only inflict a quantitative rather than qualitative change in the selection pressure on the host.  相似文献   

19.
Children and youth with type 1 diabetes show an enhanced prevalence of psychiatric disorders, especially depression and eating disorders. Their parents suffer from constant vigilance, fear of hypoglycaemia and worries about their child’s future. Children’s quality of life corresponds largely to the quality of life of healthy peers, but is influenced by glycemic control and family conflicts. Illness related family conflicts increase in adolescence, when parental supervision of diabetes therapy run contrary to adolescents’ needs of autonomy. A stepwise transfer of treatment responsibility, which is adjusted to the child’s developmental status, should begin in adolescence at the earliest. The psychosocial care of patient families from diagnosis on should be an integral part of treatment and include patient education programs as well as psychological single case and group intervention.  相似文献   

20.
Germination phenology data have been collected from 75 winter annuals, 49 summer annuals, 28 monocarpic perennials, and 122 polycarpic perennials, and experimental investigations of dormancy breaking and germination requirements have been conducted on 56 winter annuals, 32 summer annuals, 18 monocarpic perennials, and 73 polycarpic perennials. The purpose of these studies was to determine if there are correlations between the dormancy breaking and germination requirements of seeds and the germination phenology, life cycle type, habitat requirements, range of geographical distribution, and phylogenetic relationships of the species. Germination phenology is highly correlated with the responses of seeds to the yearly temperature cycle. Species with winter and summer annual life cycles have predictable germination characteristics, but monocarpic and polycarpic perennials do not. Several dormancy types may be found in a given habitat, and narrowly endemic and widely-distributed species in the same genus may have similar germination characteristics. Within some families there is a tendency for a particular type of seed-temperature response to be very important, but frequently this is related to the predominance of a given life cycle type in the family.  相似文献   

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