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A chronological review of the history of research in canine behavioral genetics is presented. Prior to the work of Scott and Fuller, many studies attempted to describe observed results in simple Mendelian terms. More recently, a quantitative mode of inheritance has been ascribed to many behavioral traits, and heritabilities have been calculated in different populations. Studies of behavioral traits are complicated by the effects of learning, which may well explain the reports of low heritability of behavioral traits measured on adults. Both genotype and environment have been shown to play major roles in the expression of behavioral traits. Maternal effects and the sex of an individual have important effects on behavior scores. Breeders usually select for both physical and behavioral traits in the same individuals, and this review includes a summary of reported research on the relationships between physical and mental traits.  相似文献   

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This paper reviews the interactions of insects with food packaging, and measures which may be taken to limit damage.  相似文献   

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In 1898 the U. S. Department of Agriculture be?an importation of economically important plants for possible cultivation and utilization in the United States. Since then nearly a quarter million introductions have been made, including the hard winter wheats which today are ?rown annually on some 27 million acres, and soybeans which now support a billion-dollar industry.  相似文献   

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Equilibrative nucleoside transporters (ENTs) are polytopic integral membrane proteins that mediate the transport of nucleosides, nucleobases, and therapeutic analogs. The best-characterized ENTs are the human transporters hENT1 and hENT2. However, non-mammalian eukaryotic ENTs have also been studied (e.g., yeast, parasitic protozoa). ENTs are major pharmaceutical targets responsible for modulating the efficacy of more than 30 approved drugs. However, the molecular mechanisms and chemical determinants of ENT-mediated substrate recognition, binding, inhibition, and transport are poorly understood. This review highlights findings on the characterization of ENTs by surveying studies on genetics, permeant and inhibitor interactions, mutagenesis, and structural models of ENT function.  相似文献   

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Conservation management recommendations for saproxylic invertebrates advocate the continuous provision of the dead and decaying wood microhabitats that they require for survival. Accepted site-based management practices include leaving fallen dead and decaying wood in situ, providing supplementary coarse woody material (CWM), inducing decay in mature trees and strategic planting in order to maintain a balanced age structure of trees in both space and time. Here we examine the empirical evidence regarding the effectiveness of such interventions using rigorous systematic review methodology. Systematic searching yielded 27 studies containing pertinent information. The evidence presently available is insufficient to critically appraise the utility of any specific intervention for conserving saproxylic species, or assemblages, in the long-term. However, there are a range of studies, conducted over relatively short periods of time, which do describe changes in saproxylic fauna in response to management practices. In the absence of robust, high quality evidence, recommendations relating to the use of specific site-based conservation interventions should only be regarded as speculative. Nonetheless, general proposals for the maintenance of suitable microhabitats, such as the protection of veteran trees within the landscape, are based on sound ecological principles and should be encouraged even though experimentally controlled and replicated evidence is lacking. Further primary research and long-term monitoring are required to fill the gaps in our ecological knowledge that potentially weaken the case for the effectiveness of current saproxylic invertebrate conservation action and would enable practitioners to make better informed decisions with regard to dead wood protection and provision.  相似文献   

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Vancomycin belongs to the vancomycin-ristocetin family of glycopeptides, and is a subclass of linear sugar containing peptides composed of seven amino acids. Its stereochemical configuration forms the basis of a particular mode of action, though its complexation with the D-alanyl-D-alanine terminus of peptidoglycon monomer. The glycosylated hexapeptide chain consists of chloro-β-hydroxytyrosines, p-hydroxyphenylglycines, N-methylleucine and aspartic acid forms a rigid molecular frame work and gives the difficulty in the analysis. Vancomycin in the serum samples is usually estimated by liquid chromatography and the bacterial sensitivity was genereally tested by the microbiological assay. The present review deals with the qualitative, quantitative, microbiological and immunological assays and the comparison of the quantitative methods. Clinical implications of vancomycin have also been cited in the review.  相似文献   

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Summary Mental retardation, in particular the X-linked type, has interested geneticists for many years. An increasing number of affected families have been to genetic counselling centres, and an effort is being made to find clinical and cytogenetic methods so a reliable diagnosis can be made. This would enable the detection of carriers and the opportunity to offer prenatal diagnosis. Many questions remain regarding X-linked mental retardation, its causes, diagnosis, and prevention. In this article we try to give an overview about the status of our present knowledge and the questions to be answered in the future.  相似文献   

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Agrobacterium rhizogenes transfers a segment of its plasmid to the plant genome. The transferred DNA contains genes which are involved in the synthesis of plant hormones. These genes express in the plant cell and give rise to rooty-tumors at the infection site. Transgenic plants can be readily regenerated from the rooty-tumors and the transferred DNA is transmitted to progeny plants. High regeneration potential and sustained maintenance of transferred DNA makes the bacterium a suitable vector for plant genetic engineering. DNA sequences homologous to the transferred DNA ofAgrobacterium rhizogenes were detected in some untransformed plant species suggesting a past infection byAgrobacterium rhizogenes during evolution of some genera, notably Nicotiana.  相似文献   

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Traditional human communities have a wide knowledge of their environment. Collection of animals in estuarine and coastal areas are directly influenced by tidal cycles. The aim of this study is to evaluate the understanding of the tides associated with the lunar cycle held by people who gather crustaceans and molluscs in the State of Paraiba. The empirical knowledge of 20 crab gatherers and 30 mollusc gatherers was recorded through open interviews and structured questionnaires. The results showed that the gatherers have an accurate comprehension of tidal phenomenon based on their exploitation of natural resources, which perpetuates through generations.  相似文献   

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Coral reefs are among the most biologically diverse and economically important ecosystems on the planet. The deposition of massive calcium carbonate skeletons (biomineralization or calcification) by scleractinian corals forms the coral reef framework/architecture that serves as habitat for a large diversity of organisms. This process would not be possible without the intimate symbiosis between corals and photosynthetic dinoflagellates, commonly called zooxanthellae. Carbonic anhydrases play major roles in those two essential processes of coral’s physiology: they are involved in the carbon supply for calcium carbonate precipitation as well as in carbon-concentrating mechanisms for symbiont photosynthesis. Here, we review the current understanding of diversity and function of carbonic anhydrases in corals and discuss the perspective of theses enzymes as a key to understanding impacts of environmental changes on coral reefs.  相似文献   

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What happens to the DNA vaccine in fish? A review of current knowledge   总被引:1,自引:0,他引:1  
The primary function of DNA vaccines, a bacterial plasmid DNA containing a construct for a given protective antigen, is to establish specific and long-lasting protective immunity against diseases where conventional vaccines fail to induce protection. It is acknowledged that less effort has been made to study the fate, in terms of cellular uptake, persistence and degradation, of DNA vaccines after in vivo administration. However, during the last year some papers have given new insights into the fate of DNA vaccines in fish. By comparing the newly acquired information in fish with similar knowledge from studies in mammals, similarities with regard to transport, blood clearance, cellular uptake and degradation of DNA vaccines have been found. But the amount of DNA vaccine redistributed from the administration site after intramuscular administration seems to differ between fish and mammals. This review presents up-to-date and in-depth knowledge concerning the fate of DNA vaccines with emphasis on tissue distribution, cellular uptake and uptake mechanism(s) before finally describing the intracellular hurdles that DNA vaccines need to overcome in order to produce their gene product.  相似文献   

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Any experiment involving living organisms requires justification of the need and moral defensibleness of the study. Statistical planning, design, and sample size calculation of the experiment are no less important review criteria than general medical and ethical points to consider. Errors made in the statistical planning and data evaluation phase can have severe consequences on both results and conclusions. They might proliferate and thus impact future trials—an unintended outcome of fundamental research with profound ethical consequences. Unified statistical standards are currently missing for animal review boards in Germany. In order to accompany, we developed a biometric form to be filled and handed in with the proposal at the concerned local authority on animal welfare. It addresses relevant points to consider for biostatistical planning of animal experiments and can help both the applicants and the reviewers in overseeing the entire experiment(s) planned. Furthermore, the form might also aid in meeting the current standards set by the 3+3R's principle of animal experimentation: Replacement, Reduction, Refinement as well as Robustness, Registration, and Reporting. The form has already been in use by the concerned local authority of animal welfare in Berlin, Germany. In addition, we provide reference to our user guide giving more detailed explanation and examples for each section of the biometric form. Unifying the set of biostatistical aspects will help both the applicants and the reviewers to equal standards and increase quality of preclinical research projects, also for translational, multicenter, or international studies.  相似文献   

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Pollen as food and medicine—A review   总被引:2,自引:0,他引:2  
Pollen, the male gametophyte of flowering plants, is a high energy material, which is collected by insects and stored as food reserve. Pollen has been used traditionally by humans for religious purposes and as supplementary food. Pollen is a concentrated, energy and vitamin rich food that in contemporary times is not only consumed as a dietary component, but also is used in alternative medical treatments. Pollen has potential imporiance as a supplementary and survival food, and for conditioning of athletes. Pollen has been used medically in prostatitis, bleeding stomach ulcers and some infectious diseases, although such use has been questioned by the medical profession. Pollen may also be used for treatment and prevention of the high-altitude-sickness syndrome. Because some individuals are allergic to pollen, and various pollen species contain specific allergens, individual sensitivities must be tested before pollen is used as a treatment or as a supplementary food.  相似文献   

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Summary Methionine dependence is a defect found in many cancer cell lines that inhibits their growth in culture when methionine is replaced by its immediate precursor, homocysteine, in the culture medium. Normal cultured cells do not have this defect. This report lists the diverse and large number of animal and human cancer lines that are methionine-dependent, and critically reviews the cell biology and methionine biochemistry of the phenomenon. This work was supported by Grant CA27564 from the National Institutes of Health; The Council for Tobacco Research-USA, Inc.; The United Cancer Council, Inc.; The Cancer Research Coordinating Committee of the University of California; Grants from the Academic Senate, University of California, San Diego; and a Special Fellowship to R. M. H. from the Leukemia Society of America. An erratum to this article is available at .  相似文献   

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《Process Biochemistry》2014,49(5):872-881
Ionic liquids (ILs) have attracted much attention in both academics and industries as promising solvents for a diverse range of applications. However, there were little industrial processes employing ILs as current time due to the economical and efficient use of ILs. The economic efficiency can be improved by recycling and reuse of ILs. In the last few decades, several attempts have been made, by the researchers, for recovery and recycling of ILs. This review is intended to present a comprehensive summary on the methods used for recovery and recycling of ILs.  相似文献   

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