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1.
Interaction of gene wellhaarig (we) with genes waved alopecia (wal) and hairless (hr) was studied in mice. The mutant gene we is responsible for the development of a specific waved coat in homozygotes. Homozygous mice carrying mutant gene wal also have a wavy coat, though a partial alopecia develops with time in these animals. In homozygotes for the hr gene, hair loss is observed beginning from the age of ten days. A series of crosses we/we and wal/wal yielded animals with we/+wal/wal and we/we wal/wal genotypes. In mice we/+wal/wal carrying gene we at a single dose, alopecia is accelerated significantly as compared to the single-dose homozygotes +/+wal/wal. In we/we wal/wal mice, alopecia starts earlier than in we/+wal/wal mice; by the age of one month, the double homozygotes are almost hairless except for small body areas covered with a sparse coat. In addition, curliness of the first-generation hair in mice we/we wal/wal is much more expressed than in +/+wal/wal and we/we+/+ mice. The obtained evidence suggests that the we gene is a modifier of the wal gene because the former enhances the effects of the wal gene, which is confirmed by the earlier onset of alopecia and progression of the latter in mice having the we/+wal/wal genotype and especially in we/we wal/wal animals. The we/we hr/+ mice do not differ in coat from we/we+/+ mice; in both cases, the coat is wavy. The coat of double homozygotes we/we hr/hr, is similar to that of we/we+/+ mice until ten days of age, when the signs of alopecia appear. By the age of 21 days, mice we/we hr/hr have lost their coat completely like mice +/+ hr/hr. Hence, the we gene is a modifier of the wal gene though it does not interact with hr gene during the coat formation.  相似文献   

2.
In this paper, we establish a new global phenomenological model of ischemic stroke. It takes into account local ischemia, energy reduction, propagation of spreading depressions (SD), damages to the cells and cellular death by apoptosis or necrosis. The spatial diffusion of the ions in the extracellular space which triggers the propagation of SD is a central point here. First we expose the various biological hypotheses that we have made in this model, and then we explain how to determine the parameters and solve the system of equations that we obtain. Next we present some results of this model: we simulate a KCl injection and then a local ischemia. Finally we discuss results and propose some improvements for this model.  相似文献   

3.
J. Fayn  N. Vuillerme 《IRBM》2013,34(1):18-20
In this paper, we briefly describe the eHealth theme of GdR STIC-Santé we created in January 2011, then we summarize the main contributions to the promotion, development, organization and diffusion of research, innovation, education and training initiatives in the field of eHealth we provided in 2011–2012, and we finally draw some perspectives for future works for the coming years.  相似文献   

4.
"国际生物多样性观察年"(IBOY)介绍   总被引:2,自引:1,他引:1  
任毅  赵士洞  李云 《生物多样性》2000,8(1):126-129
“国际生物多样性观察年”(IBOY)是由DIVERSITAS所筹划的旨在对全球生物多样性现状从不同层次进行综合研究的一项计划。该计划的主要目标包括:促进公众对生物多样性现状和未来的了解、促进生物多样性学科的发展和完善以及为政府决策过程提供科学依据。DIVERSITAS试图通过该项计划,了解我们所面临的全球性生物多样性现状、全球生物多样性丧失的程度及其原因、生物多样性的丧失给人类生活所带来的威胁、我们怎样保护和发展生物多样性这一人类共同的财富以及探索评估全球生物多样性现状的手段等方面的问题。本文同时还对实施“国际生物多样性观察年”计划所提出的一些提议进行了简要介绍。  相似文献   

5.
Computer-based remote monitoring of our environment is increasingly based on combining data derived from in-situ-sensors with data derived from remote sources, such as satellite images or CCTV. In such deployments it is necessary to continuously monitor the accuracy of each of the sensor data streams so that we can account for sudden failures of sensors, or errors due to calibration drive or biofouling. In multimedia information retrieval (MMIR), we search through archives of multimedia artefacts like video programs, by implementing several independent retrieval systems or agents, and we combine the outputs of each retrieval agent in order to generate an overall ranking. In this paper we draw parallels between these seemingly very different applications and show how they share several similarities. In the case of environmental monitoring we also need some mechanism by which we can establish the trust and reputation of each contributing sensor, though this is something we do not need in MMIR. In this paper we present an outline of a trust and reputation framework we have developed and deployed for monitoring the performance of sensors in a heterogeneous sensor network.  相似文献   

6.
Robert R. Dunn 《Biotropica》2010,42(5):555-557
Increasingly, we view nature through a utilitarian lens that leads us to attempt to measure and manage the services that species, habitats and ecosystems provide. Surprisingly, we have tended to consider only the positive values of ecosystems, their ecosystem services. In addition to providing our food and water, Nature also kills us, primarily through disease. If we are to effectively manage the terrestrial Earth, we need to also manage species, habitats and ecosystems so as to minimize such ‘ecosystem disservices’. I consider what we know about the spatial pattern of one disservice, pathogen prevalence and how changes in habitat influence it. I consider the effects of habitat changes on pathogen prevalence and, consequently, ecosystem disservices. In the end, we need to weigh both the costs and the benefits of particular ecosystems, habitats and species – to consider the bad with the good. Doing so requires that we learn much more about the biota than we currently know.  相似文献   

7.
From presence to consciousness through virtual reality   总被引:1,自引:0,他引:1  
Immersive virtual environments can break the deep, everyday connection between where our senses tell us we are and where we are actually located and whom we are with. The concept of 'presence' refers to the phenomenon of behaving and feeling as if we are in the virtual world created by computer displays. In this article, we argue that presence is worthy of study by neuroscientists, and that it might aid the study of perception and consciousness.  相似文献   

8.
Most cancer researchers regularly practice the responsible conduct of research (RCR) without consciously considering it. As professional scientists, we simply do what we are trained to do. However, as we train a new generation of cancer researchers in our laboratories, we must be vigilant against undue complacency. In an age when misconduct in research is receiving more media attention than ever before, we should periodically take a moment of pause and reflect upon the meaning and practice of responsibly conducting research. Rather than meeting minimum standards in a compliance-driven manner, we should practice forethought and periodically consider how we can improve. We, as leaders in cancer research, must then push our peers to do the same. By embedding RCR into the culture of cancer research through a multilayer approach, including regular assessment at the levels of individual research groups, departmentally, and institutionally, we will become a model discipline in the responsible conduct of research.  相似文献   

9.
Improving our health care procedures is ideally a collaborative and ongoing process, yet it takes time we may not feel we can easily afford. If we can consider how we might make even one change to improve our procedures, we might also be able to help improve not only the capabilities and skills of each member of our health care teams but also the ability of our patients to engage in effective diabetes self-care.  相似文献   

10.
We examined the in vitro and in vivo effects of paraquat on the cell cycle. After we exposed paraquat to the cultured cell (MDCK), we examined cell kinetics by flow cytometry with BrdU-PI double staining. And we administered paraquat intravenously to the rats, we collected and separated rat's liver and pulmonary cells, and we examined the cell kinetics by same method. Consequently our study found that the cells in the S-phase were noted to be abundant, and we suggested that paraquat apparently arrested the cell cycle at S time, and that DNA damage was importance in the mechanism of paraquat toxicity.  相似文献   

11.
Emotions like regret and envy share a common origin: they are motivated by the counterfactual thinking of what would have happened had we made a different choice. When we contemplate the outcome of a choice we made, we may use the information on the outcome of a choice we did not make. Regret is the purely private comparison between two choices that we could have taken, envy adds to this the information on outcome of choices of others. However, envy has a distinct social component, in that it adds the change in the social ranking that follows a difference in the outcomes. We study the theoretical foundation and the experimental test of this view.  相似文献   

12.
Martynova MIu  Isaev DA  Koniukhov BV 《Genetika》2002,38(11):1511-1517
The mutant gene wellhaaring (we) confers the waved coat in mice, which is most pronounced in homozygotes at 10 to 21 days of postnatal development. Abnormal hair growth and structure in the we/we mutant mice results from defective cell differentiation in the inner root sheath of a hair follicle. To localize the site of the we gene action, we obtained ten chimeric mice by aggregation of the early C57BL/6-2we/we and BALB/c embryos. The chimera coat was waved, shaggy, or almost normal depending on the percentage of the mutant component. In the we/we +/+ chimeric animals of the first generation (G1) aged 21 days, both mutant and normal hair phenotypes were observed, which was especially discernible in zigzag hair. Note that none of the chimeras exhibited the alternating patterns of transversely oriented stripes or patches of either mutant or normal hair; i.e., they had a mixed parental hair phenotype. We also did not observe the animals with an intermediate phenotype, which suggests a discontinuous hair formation in chimeras according to the "all or nothing" principle. The data obtained indicate that the dermal papilla cells of a hair follicle are the sites for the we gene action. During the embryonic development, dermal cells are strongly mixed, which accounts for the lack of the clear-cut transverse stripes of either mutant or normal hair. The mutant gene we is probably responsible for a disrupted induction signal from the dermal papilla towards ectodermal cells of a hair follicle.  相似文献   

13.
Both medicine and the history of medicine have seen many changes in the last four decades. The way we tell the story of medical developments no longer concentrates on the important doctors and their ideas. The influences of social history in the 1960s and 1970s and cultural history in the 1980s and 1990s have broadened and enriched the interpretations of our medical past. The social historians have helped us to include politics, economics, and the leading ideas of any period we wanted to study; the cultural approach has added ethnography as well as an emphasis on language or discourse.Today there is a new history of medicine, one far more willing to cross disciplinary boundaries to ask questions about how we know what we know and why we do what we do.This article highlights some of the work in the adjoining fields of medical anthropology and of literature and medicine to demonstrate new interests, new questions, and new methods of inquiry. However, although we have cast our nets far more widely in the process of professionalizing the history of medicine, there is a question about whether we have lost the appeal to one of our core constituencies: medical students and physicians. We need to welcome some of the new changes in medical history as in medicine itself; the common goal is to achieve a better understanding of what we have done and what we are doing.  相似文献   

14.
Interaction of gene wellhaarig (we) with genes waved alopecia(wal) and hairless (hr) was studied in mice. The mutant gene weis responsible for the development of a specific waved coat in homozygotes. Homozygous mice carrying mutant gene walalso have a wavy coat, though a partial alopecia develops with time in these animals. In homozygotes for thehr gene, hair loss is observed beginning from the age of ten days. A series of crosses we/weand wal/wal yielded animals with we/+wal/wal and we/we wal/wal genotypes. In micewe/+wal/wal carrying gene we at a single dose, alopecia is accelerated significantly as compared to the single-dose homozygotes +/+wal/wal. In we/we wal/wal mice, alopecia starts earlier than in we/+wal/wal mice; by the age of one month, the double homozygotes are almost hairless except for small body areas covered with a sparse coat. In addition, curliness of the first-generation hair in mice we/we wal/wal is much more expressed than in +/+wal/wal and we/we+/+ mice. The obtained evidence suggests that the wegene is a modifier of the wal gene because the former enhances the effects of the walgene, which is confirmed by the earlier onset of alopecia and progression of the latter in mice having the we/+wal/wal genotype and especially in we/we wal/wal animals. The we/we hr/+ mice do not differ in coat from we/we+/+ mice; in both cases, the coat is wavy. The coat of double homozygotes we/we hr/hr, is similar to that of we/we+/+ mice until ten days of age, when the signs of alopecia appear. By the age of 21 days, mice we/we hr/hr have lost their coat completely like mice +/+ hr/hr. Hence, the we gene is a modifier of the walgene though it does not interact with hrgene during the coat formation.  相似文献   

15.
In this general, strongly pro-animal, and somewhat utopian and personal essay, I argue that we owe aquatic animals respect and moral consideration just as we owe respect and moral consideration to all other animal beings, regardless of the taxonomic group to which they belong. In many ways it is more difficult to convince some people of our ethical obligations to numerous aquatic animals because we do not identify or empathize with them as we do with animals with whom we are more familiar or to whom we are more closely related, including those species (usually terrestrial) to whom we refer as charismatic megafauna. Many of my examples come from animals that are more well studied but they can be used as models for aquatic animals. I follow Darwinian notions of evolutionary continuity to argue that if we feel pain, then so too do many other animals, including those that live in aquatic environs. Recent scientific data ('science sense') show clearly that many aquatic organisms, much to some people's surprise, likely suffer at our hands and feel their own sorts of pain. Throughout I discuss how cognitive ethology (the study of animal minds) is the unifying science for understanding the subjective, emotional, empathic, and moral lives of animals because it is essential to know what animals do, think, and feel as they go about their daily routines. Lastly, I argue that when we are uncertain if we are inflicting pain due to our incessant, annoying, and frequently unnecessary intrusions into the lives of other animals as we go about 'redecorating nature' (removing animals or moving them from place to place), we should err on the side of the animals and stop engaging in activities that cause pain and suffering.  相似文献   

16.
The most important epistemological problem in psychiatry is the detection of malingering. This is a consequence of the fact that there is no objective way to confirm any psychiatric diagnosis. Psychiatric diagnosis is based on subjective complaints. The discovery of objective markers for psychiatric diagnosis is problematic because it presupposes we can tell valid from faked subjective symptoms. But this is the difficulty. If we use pervasive irrationality as a sign of mental illness, we encounter the problem of identifying pervasive irrationality. To understand someone's behaviour, we have to assume it is largely rational. This precludes us from using behaviour to separate genuine from faked mental illness. There are a number of strategies used to solve any epistemological problem, and the most successful is the hypothetico-deductive method. If we use this, we can solve our epistemological problem. Genuine mental illness can be identified when it is the best explanation of the person's overall behaviour. Consilience of inductions is critical in supporting the validity of such explanations. This implies that it is merely a hypothesis that mental illness exists, and that we might discover that many mental illnesses, perhaps all, do not exist. We must embrace this possibility--only if we take a risk will we gain any knowledge.  相似文献   

17.
研究可交换条件下多维结构回归模型中总体平均处理效应的混杂因子的控制和排序问题,利用矩阵的迹定义混杂因子的控制效率,通过控制效率来控制混杂因子,并给出混杂因子的排序,同时给出一个应用实例。  相似文献   

18.
In this paper we present an axiomatic theory of evolution which is inspired by the reading of a paper written by G.V. Schiaparelli in 1898. Schiaparelli was a famous astronomer, but he also studied the Darwinian ideas. We propose five axioms which can characterize the theory of evolution. We have also written these axioms using the language of the logic of predicates of first order with some constant monadic and dyadic predicates and appropriate functionals. But we can use other types of logic. So we can examine the concepts of species and of speciation. Then we introduce the interesting notion of generation distance. Moreover we give a theorem which establishes a geometrical model of our theory. If we analyze further the fourth axiom (which concerns the notion of generation distance) we can propose an elementary dynamical model by which we can represent possible evolutionary dynamics. These dynamics partially depend on random quantities.  相似文献   

19.
Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This eighth installment of Explorations in Statistics explores permutation methods, empiric procedures we can use to assess an experimental result-to test a null hypothesis-when we are reluctant to trust statistical theory alone. Permutation methods operate on the observations-the data-we get from an experiment. A permutation procedure answers this question: out of all the possible ways we can rearrange the observations we got, in what proportion of those arrangements is the sample statistic we care about at least as extreme as the one we got? The answer to that question is the P value.  相似文献   

20.
In recent years, progress has been made on in both micro- and nano-sized materials. At the same time, the advances in biology, specifically in genomics, have provided us with a wealth of information that can now be put into research applications and hopefully clinical practice. In our research center in Niskayuna, NY, we have been working on advanced technologies and novel approaches in both areas. Here we show several examples of how we have addressed different topics in our research. In addition, we will show, how we are combining nanotechnology with advanced biology. In particular, we will show examples of using nanoparticles for different applications in vitro and in vivo. We will also show the context for both technology areas and the applications of strategic importance.  相似文献   

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