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1.
The number of "private" electrophoretic variants of enzymes controlled by 25 loci has been used to obtain estimates of mutation rate in Australian Aborigines. Three different methods yield values of 6.11 X 10(-6), 2.78 X 10(-6), and 12.86 X 10(-6)/locus per generation for the total sample of Aborigines. One tribal population of Waljbiri in central Australia gives values of 2.99 X 10(-6) and 2.04 X 10(-6) for two of the methods, the third being unapplicable. The mean mutation rate for the total Aboriginal sample of 7.25 X 10(-6) is very similar to the value obtained by Neel and his colleagues for Amerindians in South America.  相似文献   

2.
ABSTRACT: BACKGROUND: Prescribing errors are a major source of morbidity and mortality and represent a significant patient safety concern. Evidence suggests that trainee doctors are responsible for most prescribing errors. Understanding the factors that influence prescribing behavior may lead to effective interventions to reduce errors. Existing investigations of prescribing errors have been based on Human Error Theory but not on other relevant behavioral theories. The aim of this study was to apply a broad theory-based approach using the Theoretical Domains Framework (TDF) to investigate prescribing in the hospital context among a sample of trainee doctors. METHOD: Semistructured interviews, based on 12 theoretical domains, were conducted with 22 trainee doctors to explore views, opinions, and experiences of prescribing and prescribing errors. Content analysis was conducted, followed by applying relevance criteria and a novel stage of critical appraisal, to identify which theoretical domains could be targeted in interventions to improve prescribing. RESULTS: Seven theoretical domains met the criteria of relevance: "social professional role and identity," "environmental context and resources," "social influences," "knowledge," "skills," "memory, attention, and decision making," and "behavioral regulation." From critical appraisal of the interview data, "beliefs about consequences" and "beliefs about capabilities" were also identified as potentially important domains. Interrelationships between domains were evident. Additionally, the data supported theoretical elaboration of the domain behavioral regulation. CONCLUSIONS: In this investigation of hospital-based prescribing, participants' attributions about causes of errors were used to identify domains that could be targeted in interventions to improve prescribing. In a departure from previous TDF practice, critical appraisal was used to identify additional domains that should also be targeted, despite participants' perceptions that they were not relevant to prescribing errors. These were beliefs about consequences and beliefs about capabilities. Specifically, in the light of the documented high error rate, beliefs that prescribing errors were not likely to have consequences for patients and that trainee doctors are capable of prescribing without error should also be targeted in an intervention. This study is the first to suggest critical appraisal for domain identification and to use interview data to propose theoretical elaborations and interrelationships between domains.  相似文献   

3.
Methods of reviewing health care already exist in Britain, but the debate continues about how practical and acceptable such a review is. The many different terms used to describe review only confuse the issue. "Audit" is a useful term for describing the review of medical work by medical people. This can be divided into "internal audit," or peer review, and "external audit"--that is, review by organisations outside hospital and general practice. The concepts of internal and external audit have a great impact upon the attitudes held by the medical profession about audit. The shortcomings of audit by the professional standards review organisations in the United States are not inevitable in Britian.  相似文献   

4.
We are very frequently told that peasants are exploited without being told what exactly this means, whether peasant exploitation is confined to peasants, or whether the word exploitation is meant to convey different meanings for different societies. This paper discusses two meanings of exploitation, neither of which relates uniquely to peasantry, and poses specific questions about "exploitation" and "surplus," the answers to which would tell us a good deal about what is meant by the exploitation of peasantry.  相似文献   

5.
Undergraduate students in the Department of Biomedical Sciences at the University of South Alabama, Mobile, are required to take a course entitled "Issues in Biomedical Sciences," designed to increase students' awareness about bioethical questions and issues concerning research integrity. This paper describes the main features of this course and summarizes the results of a survey designed to evaluate the students' perceptions about the course. A summary of this study was presented at the 2002 Conference on Research Integrity in Potomac, MD, sponsored by the Office of Research Integrity of the National Institutes of Health.  相似文献   

6.
Research on the relationship between Aborigines and pastoralists in the Northen Territory can be divided into two traditions. A ‘Liberal-managerial’ tradition, represented by the work of Stevens and the Berndts, fails to explore Aborigines' constructs about that relationship. An alternative ‘ethnographic’ tradition has begun to correct this imbalance by using Aborigines' testimony. An interpretation of these materials suggests that Aborigines applied a model of exchange to their dealings with pastoralists and that their capacity to do so has been undermined by the gradual emergence of wage-labour relations in the industry.  相似文献   

7.
The 'fire stick farming model, which suggests that Aborigines changed the frequency and nature of fires in order to manipulate animal and plant resources, is now widely accepted in Australian phehistory. A re-examination of the biological evidence suggests that Aboriginal use of fire had little impact on the environment and that the patterns of distribution of plants and animals which obtained 200 years ago would have been essentially the same whether or not Aborigines had previously been living here. It is further suggested that 'fire stick farming’, had it been attempted, would in fact have been counter productive economically because of the adverse effects it would have had upon small species of animals. Aborigines observed and made use of an existing natural fire regime in Australia, they did not attempt to develop a new one.  相似文献   

8.
Ian Abbott 《Oecologia》1979,44(3):347-354
Summary The occurrence of kangaroos, wallabies and related species (Family Macropodidae) on islands of area 90 ha or more round Australia is non-random. Few islands adjacent to the northwestern, northern and eastern coasts have macropods present in contrast to a large number of islands near the mid-and southwestern coasts and most of the southern coastline. The latter group of islands was not visited by aborigines because they lacked watercraft, and most of the islands were apparently too small to support human populations. It is argued that Aboriginal man, through direct predation, his introduction of the Dingo, and his frequent use of fire, was chiefly responsible for the difference in representation of macropods on the two groups of islands.The median area of islands with at least one macropod species present and which are used by Aborigines is about six times larger than that of islands with at least one macropod species present and not visited or occupied by Aborigines. Several possible alternative hypotheses to account for the distribution pattern described above are discussed. For two of these hypotheses inadequate data are at hand to assess their significance.It is suggested that the median area of islands visited or occupied by Aborigines provides a guide to reserve sizes necessary for the conservation of macropods on mainland Australia. Areas of at least 5,000 ha are probably needed for the local long-term persistence of at least one species of macropod, and areas of 9,000 ha for the long-term survival in reserves of at least two macropod species.  相似文献   

9.
In presenting data on social relations between Aborigines and Whites at a north Australian Aboriginal settlement, this paper develops the concepts of domain and social closure as important in the study of power and race-relations. Previous Australian studies in this area have not treated adequately, the substantive nature and theoretical significance of spatial and social separation between Aborigines and Whites. I argue that Aborigines retain some autonomy within a ‘Blackfella domain’, through effecting a form of exclusionary social closure.  相似文献   

10.
P T Dick 《CMAJ》1996,154(4):465-479
OBJECTIVE: To make recommendations to physicians providing prenatal care on (1) whether prenatal screening for and diagnosis of Down syndrome (DS) is advisable and (2) alternative screening and diagnosis manoeuvres. OPTIONS: "Triple-marker" screening of maternal serum levels of alpha-fetoprotein, human chorionic gonadotropin and unconjugated estriol; fetal ultrasonographic examination; amniocentesis; and chorionic villus sampling (CVS). OUTCOMES: Accuracy of detection of DS in fetuses, and risks to the mother, including psychologic distress, and to the fetus from the screening and diagnostic interventions. EVIDENCE: A MEDLINE search for relevant articles published from Jan. 1, 1966, to Mar. 31, 1994, with the use of MeSH terms "Down syndrome," "prenatal diagnosis," "screening," "prevention," "amniocentesis," "chorionic villus sampling," "ultrasonography," "anxiety," "depression" and "psychological stress" and a manual search of bibliographies, recent issues of key journals and Current Contents. VALUES: The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used. A high value was placed on providing pregnant women with the opportunity to determine whether they are carrying a fetus with DS and to make choices concerning the termination of the pregnancy. The economic issues involved are complex and were not considered. BENEFITS, HARMS AND COSTS: Triple-marker screening identifies an estimated 58% of fetuses with DS, but it has an estimated rate of true-positive results of 0.1% and of false-positive results of 3.7% (given a risk cut-off of one chance in 190 of DS). These rates vary with maternal age and the risk cut-off chosen. Women with a known risk of having a fetus with DS (e.g., those who have had a previous child with DS) may benefit from a reduction in anxiety after confirmation that their fetus does not have DS. Screening allows women at low risk of having a child with DS to detect fetuses with the syndrome, but may cause psychologic distress if there is a false-positive screening test result. Up to 20% of women with positive results of screening tests may decline to undergo a subsequent amniocentesis. Amniocentesis and CVS are very accurate in diagnosing DS in fetuses and have a very low rate of serious complications for the mother. Amniocentesis is associated with a 1.7% rate of fetal loss when it is performed after 16 weeks'' gestation, whereas the rate among controls is 0.7% (for a difference of 1%, 95% confidence interval 0.3% to 1.5%). CVS entails a greater risk of fetal loss than amniocentesis (odds ratio 1.32, 95% confidence interval 1.11 to 1.57). There is little evidence from controlled trials of significant associations between amniocentesis or CVS and neonatal morbidity or malformations; however, samples have been too small to show differences in rare outcomes. Results from some case-control studies suggest that CVS increases the risk of transverse limb deficiency. Costs were not considered because they are beyond the scope of this review. RECOMMENDATIONS: There is fair evidence to offer triple-marker screening through a comprehensive program to pregnant women under 35 years of age (grade B recommendation). Women given detailed information about serum-marker screening show more satisfaction with the screening than those not given this information. There is fair evidence to offer amniocentesis or CVS to pregnant women 35 years of age and older and to women with a history of a fetus with DS or of a chromosome 21 anomaly (grade B recommendation). Information on the limitations and advantages of each procedure should be offered. Triple-marker screening may be offered as an alternative to CVS or amniocentesis to pregnant women over 35. VALIDATION: Recommendations concerning prenatal diagnosis are similar to those of the US Preventive Services Task Force, the Society of Obstetricians and Gynaecologists of Canada, the Canadian College of Medical Geneticists and the Cochrane Pregnancy and Childbirth Group. No previous specific recommendations concerning triple-maker screening exist. SPONSORS: These guidelines were developed and endorsed by the Canadian Task Force on the Periodic Health Examination, which is funded by Health Canada and the National Health Research and Development Program.  相似文献   

11.
Vacuolar compartmentalization or cell wall binding in leaves could play a major role in hyperaccumulation of heavy metals. However, little is known about the physiology of intracellular cadmium (Cd) sequestration in plants. We investigated the role of the leaf cells in allocating metal in hyperaccumulating plants by measuring short-term (109)Cd and (65)Zn uptake in mesophyll protoplasts of Thlaspi caerulescens "Ganges" and Arabidopsis halleri, both hyperaccumulators of zinc (Zn) and Cd, and T. caerulescens "Prayon," accumulating Cd at a lower degree. The effects of low temperature, several divalent cations, and pre-exposure of the plants to metals were investigated. There was no significant difference between the Michaelis-Menten kinetic constants of the three plants. It indicates that differences in metal uptake cannot be explained by different constitutive transport capacities at the leaf protoplast level and that plasma and vacuole membranes of mesophyll cells are not responsible for the differences observed in heavy metal allocation. This suggests the existence of regulation mechanisms before the plasma membrane of leaf mesophyll protoplasts. However, pre-exposure of the plants to Cd induced an increase in Cd accumulation in protoplasts of "Ganges," whereas it decreased Cd accumulation in A. halleri protoplasts, indicating that Cd-permeable transport proteins are differentially regulated. The experiment with competitors has shown that probably more than one single transport system is carrying Cd in parallel into the cell and that in T. caerulescens "Prayon," Cd could be transported by a Zn and Ca pathway, whereas in "Ganges," Cd could be transported mainly by other pathways.  相似文献   

12.
Arguments about Aborigines: Australia and the Evolution of Social Anthropology, L. R. Hiatt Cambridge: Cambridge University Press, 1996. 225 pp.
What the Bones Say: Tasmanian Aborigines, Science, and Domination. John J. Cove. Ottawa, Canada: Carleton University Press, 1995. 221 pp.  相似文献   

13.
Australian Aborigines have sometimes concluded that the camera is a dangerous magical instrument capable of stealing some essential part of a human being, or of causing illness or death. Thus cultural values may be compromised by unauthorised display or visual transmission of secret materials, by violation of mortuary restrictions, by other invasions of privacy, or by paternalistic rhetoric which makes Aborigines appear exotic. The paper argues for a co‐operative photography to avoid most of these difficulties.  相似文献   

14.
Continuing a discussion initiated by Paul Roscoe in the pages of this journal, this essay situates positivism as a social and philosophic movement adversarily responding to the "negative dialectic" of 18th- and 19th-century critical philosophy. Notably, positivistic ideologies and practices have been manifest in cultural anthropology, linguistic analysis without "meaning," and "the new archaeology." Because funding agencies have accepted the positivistic claim that it embodies "the scientific method," interpretivists and other dissidents have had to become "rice positivists," while graduate programs have required that research be fitted into a scenario of "hypothesis testing" of "theoretical problems."  相似文献   

15.
OBJECTIVE--To investigate the effect of watching different types of video on energy expenditure. DESIGN--Randomised study assessing a "pleasant," an "amusing," an "exciting," and no video film clips. SUBJECTS--12 volunteers who did not know the purpose of the study. MAIN OUTCOME MEASURES--Changes in energy expenditure, substrate use, heart rate, and aural temperature during each film clip. RESULTS--Energy expenditure was raised slightly (0.21 kJ/day) during the "exciting" film. Individual responses varied greatly. CONCLUSION--Watching different types of video seems to have little effect on resting metabolic rate.  相似文献   

16.
Molecular evolution of a multigene family in group A streptococci   总被引:15,自引:0,他引:15  
The emm genes are members of a gene family in group A streptococci (GAS) that encode for antiphagocytic cell-surface proteins and/or immunoglobulin-binding proteins. Previously sequenced genes in this family have been named "emm," "fcrA," "enn," "arp," "protH," and "mrp"; herein they will be referred to as the "emm gene family." The genes in the emm family are located in a cluster occupying 3-6 kb between the genes mry and scpA on the chromosome of Streptococcus pyogenes. Most GAS strains contain one to three tandemly arranged copies of emm-family genes in the cluster, but the alleles within the cluster vary among different strains. Phylogenetic analysis of the conserved sequences at the 3' end of these genes differentiates all known members of this family into four evolutionarily distinct emm subfamilies. As a starting point to analyze how the different subfamilies are related evolutionarily, the structure of the emm chromosomal region was mapped in a number of diverse GAS strains by using subfamily-specific primers in the polymerase chain reaction. Nine distinct chromosomal patterns of the genes in the emm gene cluster were found. These nine chromosomal patterns support a model for the evolution of the emm gene family in which gene duplication followed by sequence divergence resulted in the generation of four major-gene subfamilies in this locus.   相似文献   

17.
In the present study, the ADL index for the partially dependent older people (Demura et al., 1999) was applied to 218 bedridden (BED), 466 partially dependent (PD) and 245 independent living (IL) people in older groups. The purposes of this study were to clarify the meaning of the evaluation of this index and to examine how ADL items are useful in determining each older group. It is suggested that a perfect score with our ADL index means independent living level, and a score of zero means bedridden level. The results of discriminant analysis indicated that four items with low-difficulty, such as "eating," "going to the toilet," "tossing about in bed" and "writing," are useful in determining if the PD is becoming bedridden. While five items with high-difficulty, such as "putting on slacks," "putting on trousers," "standing up from a sitting posture," "going up stairs" and "washing the whole body," are useful in determining if the PD is becoming independent living. Furthermore, it is inferred that the possibility of falling into a bedridden situation increases when the total score is 5 or less, while the functional level is close to independent living when the total score is 13 or more. These findings make clear the meaning of the evaluation of our ADL index. Furthermore, the functional level of older population may be screened using evaluation of total and item scores of this ADL index.  相似文献   

18.
The discovery that arrestins can function as ligand-regulated signaling scaffolds has revealed a previously unappreciated level of complexity in G protein-coupled receptor (GPCR) signal transduction. Because arrestin-bound GPCRs are uncoupled from G proteins, arrestin binding can be viewed as switching receptors between two temporally and spatially distinct signaling modes. Recent work has established two factors that underscore this duality of GPCR signaling and suggest it may ultimately have therapeutic significance. The first is that signaling by receptor-arrestin "signalsomes" does not require heterotrimeric G protein activation. The second is that arrestin-dependent signals can be initiated by pathway-specific "biased agonists," creating the potential for drugs that selectively modulate different aspects of GPCR function. Currently, however, little is known about the physiological relevance of G protein-independent signals at the cellular or whole animal levels, and additional work is needed to determine whether arrestin pathway-selective drugs will find clinical application.  相似文献   

19.
This report aims to compare the prediction of the metabolic syndrome (MetS) and its components for morbidity and mortality of coronary heart disease (CHD) in a cohort of Australian Aboriginal and Torres Strait Islander adults (TSIs). A total of 2,100 adults (1,283 Aborigines and 817 TSIs) was followed up for 6 years from 2000. Outcome measures were all CHD events (deaths and hospitalizations). Baseline anthropometric measurements, blood pressure (BP), fasting blood lipids and glucose were collected. Smoking and alcohol intake was self-reported. We found MetS was more prevalent in TSI (50.3%) compared to Aborigines (33.0%). Baseline MetS doubled the risk of a CHD event in Aborigines. Increased fasting triglycerides was stronger in predicting CHD (hazard ratio (HR): 2.8) compared with MetS after adjusted for age, sex, tobacco and alcohol consumption, and baseline diabetes and albuminuria for Aborigines but not among TSIs. MetS was not more powerful than its components in predicting CHD event. In Australian Aborigines, the "triglyceridemic waist" phenotype strongly predicts CHD event, whereas among TSI, baseline diabetes mediated the prediction of increased fasting glucose for CHD event.  相似文献   

20.
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