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971.
R N Sarma  L Fish  B S Gill  J W Snape 《Génome》2000,43(1):191-198
The wheat homoeologous Group 5 chromosomes were characterized physically in terms of rice linkage blocks using a deletion mapping approach. All three chromosomes, 5A, 5B, and 5D, were shown to have a similar structure, apart from the 4A-5A translocation on the distal end of chromosome arm 5AL. The physical mapping of rice markers on the deletion lines revealed that the whole of rice chromosome 9 is syntenous to a large block, proximal to the centromere, on the long arm. Likewise, a small segment of the distal end of the long arm showed conserved synteny with the distal one-third end of the long arm of rice chromosome 3. In between those conserved regions, there is a region on the long arm of the Group 5 chromosomes which shows broken synteny. The proximal part of the short arms of the Group 5 chromosomes showed conserved synteny with a segment of the short arm of rice chromosome 11 and the distal ends showed conserved synteny with a segment of rice chromosome 12. The physical locations of flowering time genes (Vrn and earliness per se) and the gene for grain hardness (Ha) on the Group 5 chromosomes were determined. These results indicate that comparative mapping using the deletion mapping approach is useful in the study of genome relationships, the physical location of genes, and can determine the appropriate gene cloning strategy.  相似文献   
972.
Introduction     
This introduction contextualises the papers in the Special Issue by briefly reviewing anthropological interest in dance to date, and by providing a challenge to received wisdom regarding the significance of expressive cultural forms. We theorise dance practices as domains of lived experience, and position movement as a performative moment of social interchange that is not merely reflective of prior political, personal, social and cosmological relations, but also constitutive of them. We argue that a renegotiation of the relationship between dance and anthropology is required so that dance is given full recognition as an active, fraught and dynamic force in human social life.  相似文献   
973.
This paper argues that indigenous dance is a poetic politics of cross‐cultural encounter that engages Aboriginal identities with those of the Australian nation. I question the nature of this encounter in terms of a performative dialogue that is both musically and kinesically presented by indigenous communities and ‘translated’ into political discourse by the government. The sentiments of ‘translation’ raise questions as to how local ritual expressions of Aboriginal dance can mediate dialogue when presented as national spectacle. What is being meditated? What is happening in the process of evocation? In this performative nexus, I focus specifically on the poetic politics of Yolngu ritual as spectacle; the nature of performative dialogue in terms of shared dance forms between indigenous communities; the problem of the authentication of dance identities; and how corporeal dispositions of indigenous dance genres influence national sentiment by their symbolic power. I pursue these issues through an analysis of how ancestral dances have been repositioned in national performance venues, such as concerts, cultural centres and ritual arenas, as a means of asserting performative statements about indigenous positioning within the nation‐state. The nature of this dialogue raises questions of authenticity and processes of authentication. It highlights indigenous concerns to control representations of indigeneity as national event, as well as a desire to convey something of the sentiment and sentience embodied in the poetics of their ancestral performances.  相似文献   
974.
In this Perspective, Fiona Bragg and Zhengming Chen discuss the burden of diabetes in the Chinese Population.

The worldwide epidemic of diabetes continues to grow [1]. In China, the rise in prevalence has been notably rapid; about 12% of the adult population has diabetes [2], accounting for almost one quarter of cases worldwide [1] and representing a 10-fold increase over the last 3 to 4 decades. It is appropriate, therefore, that diabetes—both prevention and management—is a major focus of current health policy initiatives in China [3,4], and their success depends on reliable quantification of the burden of diabetes. Commonly used measures such as prevalence and incidence fail to capture excess mortality risks or differences in life expectancy in diabetes [5]. Moreover, they may be less easily interpreted by policy makers and affected individuals. Estimates of lifetime risks and life years spent living with diabetes in an accompanying study by Luk and colleagues provide a valuable new perspective on the burden of diabetes in the Chinese population [6].The study used Hong Kong territory-wide electronic health records data for 2.6 million adults. Using a Markov chain model and Monte-Carlo simulations, Luk and colleagues estimated age- and sex-specific lifetime risks of diabetes (incorporating both clinically diagnosed and undiagnosed diabetes) and remaining life years spent with diabetes. Their findings showed a lifetime risk of 65.9% and 12.7 years of life living with diabetes for an average 20-year old with normoglycaemia. For an average 20-year old with prediabetes the corresponding estimates were 88.0% and 32.5 years, respectively. In other words, 6 out of 10 20-year olds with normoglycaemia and 9 out of 10 with prediabetes would be expected to develop diabetes in their lifetime. The estimated lifetime risks declined with increasing age and were higher among women than men at all ages, likely reflecting women’s higher life expectancy.These estimated lifetime risks are striking and concerning. Moreover, they are notably higher than western population estimates [710], including those considering both diagnosed and undiagnosed diabetes [9,10]. An Australian study estimated that 38% of 25-year olds would develop diabetes in their lifetime [10]. Another study in the Netherlands reported 31.3% and 74.0% probabilities of developing diabetes in the remaining lifetime for individuals aged 45 years without diabetes and with prediabetes, respectively [9]. Diabetes incidence and overall mortality influence population lifetime risks. Differences in the glycaemic indicators used to identify undiagnosed diabetes may have contributed to differences between studies in diabetes incidence. In the study by Luk and colleagues, a combination of fasting plasma glucose (FPG), HbA1c levels and oral glucose tolerance testing (OGTT) was used, while in the Australian [10] and the Netherlands [9] studies, they used FPG/OGTT and mainly FPG, respectively. However, it is unlikely these differences would fully account for the large disparities seen in lifetime risk. Similarly, differences between life expectancy in Hong Kong (84.8 years), Australia (83.4 years), and the Netherlands (82.2 years) are too small to explain the differences. Interestingly, the high lifetime risks observed in Hong Kong were more comparable to those in the Indian population, estimated at 55.5% and 64.6%, respectively, among 20-year-old men and women [11]. The typical type 2 diabetes (T2D) phenotype in these Asian populations may partly explain their higher estimated lifetime risks. More specifically, T2D in both Chinese and Indian populations is characterised by onset among younger and less adipose individuals than typically observed in western populations, exacerbated by rapid urbanisation and associated unhealthy lifestyles [12].However, aspects of Luk and colleagues’ study design may have overestimated lifetime diabetes risks. Chief among these is the data source used and associated selection bias. The Hong Kong Diabetes Surveillance Database includes only individuals who have ever had a plasma glucose or HbA1c measurement undertaken in a local health authority facility. Since measurement of glycaemic indicators is more likely among individuals at greater current or future risk of dysglycaemic states, this will have inflated estimates of lifetime risk and life years spent with diabetes. Although replication was undertaken by the study authors to address this bias in the smaller China Health and Retirement Longitudinal Survey (CHARLS) cohort, it does not fully allay these concerns, with modestly lower estimated lifetime diabetes risks in the CHARLS cohort, even after accounting for its higher mortality. A further limitation is their consideration of transition to dysglycaemic states as irreversible. Although data on long-term transition between glycaemic states are lacking, reversion from prediabetes (and less commonly diabetes) to normoglycaemia is well recognised, e.g., through lifestyle interventions [13].Large-scale population-based cohort studies could valuably address many of the limitations described [14]. Furthermore, lifetime risks are, by definition, population-based and represent the risk of an average person in the population, limiting their value for communicating long-term disease risks to specific individuals. However, the extensive phenotyping (e.g., adiposity) characteristic of many large contemporary cohorts [14] would facilitate incorporation of risk factors into lifetime risk estimates, enhancing their relevance to individuals. Previous studies have found greater lifetime risks of diabetes associated with adiposity [9,11], and this approach could be extended to incorporate other established, as well as more novel (e.g., genetic), risk factors. This is arguably of particular relevance to later-onset chronic conditions, such as T2D, in which changes in risk factors during middle age can influence lifetime risks. A valuable extension of Luk and colleagues’ study will be estimation of risk factor specific lifetime diabetes risks for the Chinese population.Importantly, the limitations described do not detract from the enormity and importance of the challenge diabetes poses for China, including Hong Kong, and the estimates presented by Luk and colleagues provide valuable impetus for action. The disease burden insights can inform treatment programmes and enhance understanding of current and future impacts of diabetes and associated complications on the healthcare system. Moreover, T2D is preventable, and arguably, the greatest value of these estimated lifetime risks is in highlighting the need for, and informing the planning and provision of, diabetes primary prevention programmes. This includes identification of high-risk individuals, such as those with prediabetes, who are most likely to benefit from prevention interventions. However, the magnitude of the estimated lifetime diabetes risks, including among the large proportion of the population in a normoglycaemic state, additionally demonstrates the need for population-level prevention approaches, including environmental, structural, and fiscal strategies. Without such actions, the individual and societal consequences of diabetes for present and future generations in Hong Kong, as well as mainland China, will be immense.  相似文献   
975.
In migratory systems, variation in individual phenology can arise through differences in individual migratory behaviors, and this may be particularly apparent in partial migrant systems, where migrant and resident individuals are present within the same population. Links between breeding phenology and migratory behavior or success are generally investigated at the individual level. However, for breeding phenology in particular, the migratory behaviors of each member of the pair may need to be considered simultaneously, as breeding phenology will likely be constrained by timing of the pair member that arrives last, and carryover effects on breeding success may vary depending on whether pair members share the same migratory behavior or not. We used tracking of marked individuals and monitoring of breeding success from a partially migrant population of Eurasian oystercatchers (Haematopus ostralegus) breeding in Iceland to test whether (a) breeding phenology varied with pair migratory behavior; (b) within‐pair consistency in timing of laying differed among pair migratory behaviors; and (c) reproductive performance varied with pair migratory behavior, timing of laying, and year. We found that annual variation in timing of laying differed among pair migratory behaviors, with resident pairs being more consistent than migrant and mixed pairs, and migrant/mixed pairs breeding earlier than residents in most years but later in one (unusually cold) year. Pairs that laid early were more likely to replace their clutch after nest loss, had higher productivity and higher fledging success, independent of pair migratory behavior. Our study suggests that the links between individual migratory behavior and reproductive success can vary over time and, to a much lesser extent, with mate migratory behavior and can be mediated by differences in laying dates. Understanding these cascading effects of pair phenology on breeding success is likely to be key to predicting the impact of changing environmental conditions on migratory species.  相似文献   
976.
Global regulation of spindle-associated proteins is crucial in oocytes due to the absence of centrosomes and their very large cytoplasmic volume, but little is known about how this is achieved beyond involvement of the Ran-importin pathway. We previously uncovered a novel regulatory mechanism in Drosophila oocytes, in which the phospho-docking protein 14-3-3 suppresses microtubule binding of Kinesin-14/Ncd away from chromosomes. Here we report systematic identification of microtubule-associated proteins regulated by 14-3-3 from Drosophila oocytes. Proteins from ovary extract were co-sedimented with microtubules in the presence or absence of a 14-3-3 inhibitor. Through quantitative mass-spectrometry, we identified proteins or complexes whose ability to bind microtubules is suppressed by 14-3-3, including the chromosomal passenger complex (CPC), the centralspindlin complex and Kinesin-14/Ncd. We showed that 14-3-3 binds to the disordered region of Borealin, and this binding is regulated differentially by two phosphorylations on Borealin. Mutations at these two phospho-sites compromised normal Borealin localisation and centromere bi-orientation in oocytes, showing that phospho-regulation of 14-3-3 binding is important for Borealin localisation and function.  相似文献   
977.
A cDNA probe corresponding to the mRNA sequence for apolipoprotein E (apo E) was used to screen two independently-constructed human genomic libraries. Two recombinants (lambda E-2, and lambda E2-1), isolated using the apo E cDNA probe, also contain part or all of the apo CI gene. Hybridisation studies using both apo E and apo CI cDNA probes show that these two genes are in the same orientation and separated by 4 kb.  相似文献   
978.
979.
A set of broad-host-range vectors allowing direct selection of recombinant DNA molecules to facilitate subcloning and expression analyses of Pseudomonas genes was constructed using Bg/II lacZ alpha cassette. Controlled expression vectors pVDtac39 and pVDtac24 were shown to be useful for determination of enzymatic activities encoded by the cloned DNA fragments and Mr determination of the corresponding polypeptides. A set of Pseudomonas putida xylE gene cassettes truncated at the 5' end was constructed for translational (protein) fusion studies. A protein fusion of the Pseudomonas aeruginosa algD gene, coding for GDPmannose dehydrogenase, and the truncated xylE gene cassette was used to verify the putative coding region and translational signals predicted from the algD nucleotide sequence.  相似文献   
980.
Mutants of GAL4 protein altered in an activation function   总被引:68,自引:0,他引:68  
G Gill  M Ptashne 《Cell》1987,51(1):121-126
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