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A group of flavi-like GB viruses (GBV-A, -B, and -C) has been discovered and partially characterized. Only GBV-C is found in humans. Nucleotide sequences of the putative helicase gene of the GBV-C genome were determined in 21 Taiwanese patients and compared with isolates from Africa and North America by phylogenetic analysis. The average similarities of Taiwanese isolates to those from West Africa, East Africa, Canada, and United States were 83%, 85%, 78%, and 82%, respectively. Phylogenetic analysis of the NS3 region showed that 81% of the Taiwanese isolates were more closely related to the East African isolate. GBV-C isolates from Taiwan could be classified into at least 3 groups. These data suggest that GBV-C isolates cloned from different geographic areas have genetic heterogeneity.  相似文献   

3.
Bald eagle (Haliaeetus leucocephalus) eggs were collected during incubation, 1990-1992, from 16 nests near three bleached-kraft pulp mills, from six nests in the Fraser River estuary and from seven nests at a reference site on the Pacific coast of Canada. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were present in all eggs in a qualitatively similar pattern among sites. Mean concentrations of 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) were significantly higher in eggs collected from near three kraft pulp mill sites in the Strait of Georgia (44, 45, 84 ng/kg) than from the reference area in Johnstone Strait (15 ng/kg). There were few differences among sites in mean organochlorine pesticide levels, indicating the diffuse distribution of those chemicals and the domination of atmospheric inputs. Mean concentrations of total polychlorinated biphenyls (PCBs) were highest in eggs from the Strait of Georgia (4.86 mg/kg) and the PCB congener pattern was significantly different between that area and both the lower Fraser valley and Johnstone Strait. Mean mercury concentrations, which were mainly methyl-mercury, were significantly higher in eggs collected from the lower Fraser Valley (0.258 mg/kg) and Johnstone Strait (0.294 mg/kg) compared to the Strait of Georgia (0.188 mg/kg). Individual and regional variation in concentrations of organochlorine pesticides, PCBs and mercury in eagle eggs were thought to be influenced mainly by dietary differences. Toxicologically, in 1990, mean TCDD-toxic equivalents (TEQs) in bald eagle eggs were about two-fold greater than a lowest-observed-effect level, suggested elsewhere for this species, of 210 ng/kg TEQs. In the Strait of Georgia, PCCDs and PCDFs made a greater contribution to TEQs than non-ortho and mono-ortho PCBs, whereas the reverse was true for eggs outside the strait. Mean eggshell thickness was less than the pre-1947 value at all sites, although there was no significant relationship between eggshell thickness and DDE concentrations. Levels of other organochlorine pesticides and mercury were below those considered to be toxic.  相似文献   

4.
Sustainable design should be applied in all phases of the life cycle of a building, including programming, design, building construction, building operation, and finally demolition. This paper compares and contrasts sustainable design programs based on the life cycle of a building in North America, Europe, and Asia. Tables comparing programs from these three regions are provided for each phase in the life cycle of a building. These tables can be used by building design professionals as a reference guide to sustainable design around the world. The tables also highlight specific requirements or concerns that are applicable in a particular region. The similarities between different programs and regions can be taken into consideration during the planning of sustainable design work, regardless of the region of construction. Finally, references to more detailed program documents are provided so that interested readers can determine specific requirements that apply in a region of interest.  相似文献   

5.
A survey of all PhD programs in psychology in the US and Canada assessed the extent to which advances in statistics, measurement, and methodology have been incorporated into doctoral training. In all, 84% of the 222 departments responded. The statistical and methodological curriculum has advanced little in 20 yrs; measurement has experienced a substantial decline. Typical 1st-yr courses serve well only those students who undertake traditional laboratory research. Training in top-ranked schools differs little from that in other schools. New PhDs are judged to be competent to handle traditional techniques, but not newer and often more useful procedures, in their own research. Proposed remedies for these deficiencies include revamping the basic required quantitative and methodological curriculum, culling available training opportunities across campus, and training students in more informal settings, along with providing retraining opportunities for faculty. These strategies require attention to the human capital needs that support high-quality quantitative and methodological training and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Ice cover records from 128 freshwater lakes in the United States and Canada were analyzed. Multivariable linear regression models, log-transform models, and a combination of the two (the “hybrid” form) were used to express ice-in date, ice-out date, and maximum ice thickness as functions of mean air temperature, latitude, average depth, elevation, and surface area of each lake. Mean air temperatures are for periods from September 1 to December 31 for ice-in dates, February 1 to June 30 for ice-out dates, and September 1 to June 30 for maximum ice thickness. Data for individual years as well as averages (over the record length) for each lake were analyzed. The log-transform formulas proved best for estimating ice-in date, while the hybrid form provided the best models of maximum ice thickness. The linear regression model estimated the ice-out date best. In most cases, mean air temperature and/or latitude were the most influential parameters, followed by elevation. Lake surface area and depth had a small or no influence. R2 values of all equations ranged from 0.50 to 0.92.  相似文献   

7.
The expectation that Chinese people present distress somatically is a central prediction of cultural psychopathology and has been the subject of considerable theoretical speculation. At the same time, empirical studies have been infrequent and have yielded mixed results. The authors examined symptom presentation in Chinese (n = 175) and Euro-Canadian (n = 107) outpatients, using spontaneous problem report, structured clinical interview, and symptom questionnaire methods. All 3 methods yielded cross-culturally equivalent somatic and psychological symptom subscales. Chinese outpatients reported more somatic symptoms on spontaneous problem report and structured clinical interview compared with Euro-Canadians, who in turn reported more psychological symptoms on all 3 methods. The relation between culture and somatic symptom presentation was mediated by a tendency toward externally oriented thinking. Difficulties with identifying emotions or describing them to others did not differ significantly across cultures, supporting a nonpathological interpretation of observed differences. Psychological symptom effects were larger and more consistent than somatic symptom effects; because other studies have confirmed the ubiquity of somatic presentations worldwide, these results suggest that Western psychologization may be more culturally specific than is Chinese somatization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
Informed by a new theoretical framework that assigns a key role to cultural tasks (culturally prescribed means to achieve cultural mandates such as independence and interdependence) in mediating the mutual influences between culture and psychological processes, the authors predicted and found that North Americans are more likely than Western Europeans (British and Germans) to (a) exhibit focused (vs. holistic) attention, (b) experience emotions associated with independence (vs. interdependence), (c) associate happiness with personal achievement (vs. communal harmony), and (d) show an inflated symbolic self. In no cases were the 2 Western European groups significantly different from one another. All Western groups showed (e) an equally strong dispositional bias in attribution. Across all of the implicit indicators of independence, Japanese were substantially less independent (or more interdependent) than the three Western groups. An explicit self-belief measure of independence and interdependence showed an anomalous pattern. These data were interpreted to suggest that the contemporary American ethos has a significant root in both Western cultural heritage and a history of voluntary settlement. Further analysis offered unique support for the cultural task analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
We tested 644 serum samples from 480 grizzly bears and 40 black bears from Alaska (USA), collected between 1988 and 1991, for Toxoplasma gondii antibodies, using a commercially available latex agglutination test (LAT). A titer > or = 64 was considered positive. Serum antibody prevalence for T. gondii in grizzly bears (Ursus arctos) was 18% (87 of 480). Prevalence ranged from 9% (seven of 77) on Kodiak Island to 28% (15 of 54) in northern Alaska. Prevalence was directly correlated to age. No grizzly bears < 2-year-old had T. gondii antibody. High antibody titers were found mainly in grizzly bears captured north of the Arctic Circle. Antibody prevalence in black bears (Ursus americanus) from Interior Alaska was 15% (six of 40), similar to the prevalence in grizzly bears from the same area (13%; five of 40).  相似文献   

10.
This study examined whether universality of the 5-factor model (FFM) of personality operationalized by the Revised NEO Personality Inventory is due to genetic influences that are invariant across diverse nations. Factor analyses were conducted on matrices of phenotypic, genetic, and environmental correlations estimated in a sample of 1,209 monozygotic and 701 dizygotic twin pairs from Canada, Germany, and Japan. Five genetic and environmental factors were extracted for each sample. High congruence coefficients were observed when phenotypic, genetic, and environmental factors were compared in each sample as well as when each factor was compared across samples. These results suggest that the FFM has a solid biological basis and may represent a common heritage of the human species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Conditions influencing the distribution and abundance of Ixodes scapularis Say in North America have been the object of considerable study during the past 2 decades, resulting in new information about its expanding range, population structure, host associations, and environmental constraints. Variation in the methods, timing, or extent of sampling, the type of population estimate developed, and the spatial scale of analysis makes comparisons of results difficult. This report summarizes research on I. scapularis habitat, including the diversity of hosts and physical conditions in the environment where they are abundant, and how this may influence dispersal and range expansion. Recent efforts to analytically address spatial distributions are considered. Approaches that may be useful in clarifying and resolving unanswered questions are suggested, and a conceptual framework for analyzing this vector's expanding abundance and distribution is offered.  相似文献   

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Rabies is a widespread zoonosis that recently reached epidemic proportions in gray foxes (Urocyon cinereoargenteus) in central Texas. The objectives of this study were to determine bait and attractant preferences among captive gray foxes, to determine the behavioral responses of gray foxes to selected bait-attractant combinations, and to evaluate baits as a delivery mechanism of oral rabies vaccines. Trials were conducted to determine bait preferences of captive gray foxes to selected baits and attractants. Tested baits consisted of a polymer-bound cube made of either dog food meal or fish meal, a polymer-bound cylinder made of dog food meal, and a wax-lard cake that was enhanced with marshmallow or chicken flavoring. Attractants were additives to baits that exuded sweet, sulfurous, fruity, fatty, cheesy, honey, and fishy odors and flavors. Captive gray foxes (n = 31) exhibited a preference for marshmallow wax cakes and polymer dog food baits with a lard interior and granulated sugar exterior. However, gray foxes exhibited chewing behaviors consistent with ingesting an oral vaccine only with the wax cake baits.  相似文献   

15.
Human plasma cholesteryl ester transfer protein (CETP) is a 476-residue hydrophobic glycoprotein that catalyzes the heterotransfer of cholesteryl esters and triacylglycerols among lipoproteins: Mutations in the CETP gene have been identified, mostly in the Japanese population. These mutations result in hypercholesterolemia due to the presence of large cholesteryl ester-rich HDL particles, elevated plasma apoA-I and apoE, and reduced apoB levels. Here we report the plasma lipoprotein phenotype and molecular defect in a 57-year-old female Nova Scotian subject lacking Japanese ancestry who is homozygous for a novel mutation in the CETP gene. Her total plasma cholesterol was 7.3 mmol/l with an LDL cholesterol of 2.9 mmol/l and HDL cholesterol of 4.4 mmol/l. She was mildly hypertriglyceridemic (1.6 mmol/l) and had markedly elevated apoA-I (256 mg/dl) and apoE (14.4 mg/dl) with only slightly reduced apo/B levels (94 mg/dl). Her VLDL and LDL were cholesteryl ester-poor (1.8 and 37.2% of lipids, respectively) and triacylglycerol-rich (67.3 and 18.9% of lipids, respectively) while her HDL was cholesteryl ester-rich (40.2-45.7% of lipids) and triacylglycerol-poor (3.3-2.5% of lipids). No plasma CETP activity or mass was detected. Bi-directional DNA sequence analysis of PCR products from all 16 exons showed a single base substitution (C-->T at nucleotide 836 in exon 9 resulting in 268 Arg-->STOP) in both alleles. No other mutation was detected. A single base mismatched, 26 bp reverse PCR primer that produced a single Mae III RFLP site upon amplification of the mutated DNA sequence was designed for rapid population screening. This subject is, we believe, the first Caucasian North American patient reported to have CETP deficiency.  相似文献   

16.
In a survey of all PhD programs in psychology in the United States and Canada, the authors documented the quantitative methodology curriculum (statistics, measurement, and research design) to examine the extent to which innovations in quantitative methodology have diffused into the training of PhDs in psychology. In all, 201 psychology PhD programs (86%) participated. This survey replicated and extended a previous survey (L. S. Aiken, S. G. West, L. B. Sechrest, & R. R. Reno, 1990), permitting examination of curriculum development. Most training supported laboratory and not field research. The median of 1.6 years of training in statistics and measurement was mainly devoted to the modally 1-year introductory statistics course, leaving little room for advanced study. Curricular enhancements were noted in statistics and to a minor degree in measurement. Additional coverage of both fundamental and innovative quantitative methodology is needed. The research design curriculum has largely stagnated, a cause for great concern. Elite programs showed no overall advantage in quantitative training. Forces that support curricular innovation are characterized. Human capital challenges to quantitative training, including recruiting and supporting young quantitative faculty, are discussed. Steps must be taken to bring innovations in quantitative methodology into the curriculum of PhD programs in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Following the annexation of Austria by Hitler's Germany in 1938, officials at the eminent University of Vienna Medical School purged faculty ranks of Jews. Among those forced out were several distinguished physician dentists, several of whom emigrated to the United States. The assimilation of foreign-trained dentists raised questions at national meetings of the AADS and the National Association of Dental Examiners. Already existing ties between dental schools in Chicago and the University of Vienna, including the 1928 appointment of Rudolf Kronfeld to the faculty at Loyola, led to the relocation of Balint Orban, Harry Sicher, and Joseph Peter Weinmann in that city. Bernhard Gottlieb, who had been director of the Dental Institute in Vienna, transplanted less easily, but eventually found a niche at the Baylor College of Dentistry in Dallas. The careers of the Vienna dentist-scientists strengthened the scientific foundations of clinical dentistry in the United States, contributed to the development of a stronger research establishment, and enlarged the scope of oral biology.  相似文献   

18.
Self-enhancing and self-improving motivations were investigated across cultures. Replicating past research, North Americans who failed on a task persisted less on a follow-up task than those who succeeded. In contrast, Japanese who failed persisted more than those who succeeded. The Japanese pattern is evidence for a self-improving orientation: Failures highlight where corrective efforts are needed. Japanese who failed also enhanced the importance and the diagnosticity of the task compared with those who succeeded, whereas North Americans did the opposite. Study 2 revealed that self-improving motivations are specific to the tasks on which one receives feedback. Study 3 unpackaged the cultural differences by demonstrating that they are due, at least in part, to divergent lay theories regarding the utility of effort. Study 4 addressed the problem of comparing cultures on subjective Likert scales and replicated the findings with a different measure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
The paper summarises systematic 5-year monitoring of the environment, drinking water and food for PCDDs and PCDFs levels in industrial centres and in rural areas of the Republic of Bashkortostan, Russia. It also presents selected data on dioxin concentrations in gas emissions of toxic waste incinerators at chemical plants. The paper gives a comparative analysis of PCDDs/PCDFs daily intake by the population of industrial cities for Bashkortostan and for industrial countries of Europe and North America. The results show that PCDDs/PCDFs levels in the environment, drinking water and food in Bashkortostan are approximately equal to those in other industrial countries.  相似文献   

20.
Candida dubliniensis has been associated with oropharyngeal candidiasis in patients infected with human immunodeficiency virus (HIV). C. dubliniensis isolates may have been improperly characterized as atypical Candida albicans due to the phenotypic similarity between the two species. Prospective screening of oral rinses from 63 HIV-infected patients detected atypical dark green isolates on CHROMagar Candida compared to typical C. albicans isolates, which are light green. Forty-eight atypical isolates and three control strains were characterized by germ tube formation, differential growth at 37, 42, and 45 degreesC, identification by API 20C, fluorescence, chlamydoconidium production, and fingerprinting by Ca3 probe DNA hybridization patterns. All isolates were germ tube positive. Very poor or no growth occurred at 42 degreesC with 22 of 51 isolates. All 22 poorly growing isolates at 42 degreesC and one isolate with growth at 42 degreesC showed weak hybridization of the Ca3 probe with genomic DNA, consistent with C. dubliniensis identification. No C. dubliniensis isolate but only 18 of 28 C. albicans isolates grew at 45 degreesC. Other phenotypic or morphologic tests were less reliable in differentiating C. dubliniensis from C. albicans. Antifungal susceptibility testing showed fluconazole MICs ranging from 相似文献   

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