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Received 24 May 1999/ Accepted in revised form 21 June 1999  相似文献   

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Received 8 January 1999/ Accepted in revised form 6 April 1999  相似文献   

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In this epidemiological study the caries status of 12-year-old children was compared over time for the years 1968, 1973, 1980, 1985, 1990, 1991 and 1999. The mean number of decayed, missing and filled teeth (DMFT) decreased from 7.0 in 1968 to 2.6 in 1991. From 1991 to 1999 and increase of DMFT 2.6 in 1991, to 3.5 in 1999) has been seen which is result of war in Croatia and reorganisation of health care delivery system. With the expected continuing decline in the prevalence and severity of oral diseases, one of the main problems in the future seems to be the transition of the oral health care delivery system from a disease-oriented system to a health-oriented one.  相似文献   

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Reduced fitness among resistant versus susceptible individuals slows resistance evolution and makes it easier to manage. A loss of resistance costs could indicate novel adaptations or mutations contributing to resistance. We measured costs of resistance to imidacloprid in a Massachusetts resistant population compared with a Massachusetts susceptible population in 1999 in terms of fecundity, hatching success, egg development time, and sprint speed. Resistance was additive and seemed to be polygenic with high heritability. The fecundity cost appeared overdominant in 1999, and the hatch rate cost was partly recessive in 1999, but neither was significantly different from dominant or recessive. In 2004, we repeated our measures of resistance costs in Massachusetts in terms of fecundity and hatching success, and we added a new resistant population from Maine. In 2005, we compared development time of Maine resistant and the laboratory susceptible colony eggs. Significant fecundity costs of resistance were found in both population in both 1999 and 2004, and significant egg developmental time costs were found in 1999 and 2005. However, the hatching success costs of resistance were significant in 1999 and not apparent in 2004, suggesting some modification or replacement of the resistance genes in the intervening time.  相似文献   

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The integron-borne bla(VEB-1) gene encodes an extended-spectrum beta-lactamase. This gene was associated mostly with IS1999 and rarely with an additional IS2000 element in Pseudomonas aeruginosa isolates from Thailand, whereas IS1999 was only very rarely associated with bla(VEB-1) in Enterobacteriaceae. Expression experiments and promoter study identified promoter sequences in IS1999 that increased the expression of VEB-1 in P. aeruginosa.  相似文献   

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Falling from Grace: Downward Mobility in the Age of Affluence. Katherine S. Newman. Berkeley; University of California Press, 1999. 328 pp.
"So You Think. Drive. Cadillac?": Welfare Recipients' Perspectives on the System and Its Reform. Karen Seccombe. Boston: Allyn and Bacon, 1999. 246 PP.
Braving the Street: The Anthropology of Homelessness. Irene Glasser and Rae Bridgman. New York: Berghahn Books, 1999. 132 pp.  相似文献   

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Received 4 January 1999/ Accepted in revised form 7 April 1999  相似文献   

14.

Objectives

The purpose of this study was to examine secular changes in growth and nutritional status of Mozambican children and adolescents between 1992, 1999 and 2012.

Methods

3374 subjects (1600 boys, 1774 girls), distributed across the three time points (523 subjects in 1992; 1565 in 1999; and 1286 in 2012), were studied. Height and weight were measured, BMI was computed, and WHO cut-points were used to define nutritional status. ANCOVA models were used to compare height, weight and BMI across study years; chi-square was used to determine differences in the nutritional status prevalence across the years.

Results

Significant differences for boys were found for height and weight (p<0.05) across the three time points, where those from 2012 were the heaviest, but those in 1999 were the tallest, and for BMI the highest value was observed in 2012 (1992<2012, 1999<2012). Among girls, those from 1999 were the tallest (1992<1999, 1999>2012), and those from 2012 had the highest BMI (1999<2012). In general, similar patterns were observed when mean values were analyzed by age. A positive trend was observed for overweight and obesity prevalences, whereas a negative trend emerged for wasting, stunting-wasting (in boys), and normal-weight (in girls); no clear trend was evident for stunting.

Conclusion

Significant positive changes in growth and nutritional status were observed among Mozambican youth from 1992 to 2012, which are associated with economic, social and cultural transitional processes, expressing a dual burden in this population, with reduction in malnourished youth in association with an increase in the prevalence of overweight and obesity.  相似文献   

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Endophytic fungi in leaves of Lycopersicon esculentum Mill   总被引:1,自引:0,他引:1  
Endophytic fungi were isolated from healthy tomato leaves from field-grown plants. Several surface-sterilization techniques were assayed for removing and killing epiphytes on tomato leaves. Surface-sterilization with an undiluted commercial solution of sodium hypochlorite was employed. To determine the spectrum of endophytes, samples were collected in February 1998 and 1999 from tomato plants (cultivar Tommy) cultivated in the experimental fields of Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, Buenos Aires, Argentina. In general, different spectra of species were isolated in 1998 and 1999.Alternaria alternata was the fungus most frequently isolated from tomato leaves in 1999, but it was the second most common species in 1998. In contrast, Colletotrichum gloeosporioides was the fungus most frequently isolated in 1998, but it was not found in 1999. Species of other genera, such as Cladosporium and Penicillium, were isolated in both years.  相似文献   

17.
Sister chromatid cohesion and recombination in meiosis   总被引:10,自引:0,他引:10  
van Heemst D  Heyting C 《Chromosoma》2000,109(1-2):10-26
Sister chromatids are associated from their formation until their disjunction. Cohesion between sister chromatids is provided by protein complexes, of which some components are conserved across the kingdoms and between the mitotic and meiotic cell cycles. Sister chromatid cohesion is intimately linked to other aspects of chromosome behaviour and metabolism, in particular chromosome condensation, recombination and segregation. Recombination, sister chromatid cohesion and the relation between the two processes must be regulated differently in mitosis and meiosis. In meiosis, cohesion and recombination are modified in such a way that reciprocal exchange and reductional segregation of homologous chromosomes are ensured. Received: 11 October 1999; in revised form: 3 December 1999 / Accepted: 6 December 1999  相似文献   

18.
Abstract.  1. An ecological investigation of the shore fly community was carried out in a salt marsh in Novosedly in the Czech Republic.
2. Sampling was carried out in 1997 and 1999 at approximately 14-day intervals during the seasonally active period, using yellow water traps.
3. Altogether 14 374 specimens of the family Ephydridae were collected (6040 in 1997 and 8334 in 1999), belonging to 48 shore fly species (37 in 1997 and 41 in 1999).
4. Community structure, species richness, species diversity, evenness, and seasonal and inter-annual changes were studied. The species richness, species diversity, and evenness of the shore fly community in 1999 were higher than in 1997 but inter-annual difference in species diversity was not statistically significant. Paracoenia fumosa , Scatella tenuicosta , and Hydrellia albilabris were found to be the most abundant species in both study years.
5. Seasonal patterns and phenology of the most abundant species are discussed. Hydrellia albilabris showed similar seasonal distribution of abundance in 1997 and 1999, whereas seasonal distribution of P. fumosa and S. tenuicosta varied between the study years. Paracoenia fumosa , Hydrellia griseola , H. albilabris , Scatella paludum , S. tenuicosta , and Philotelma defecta were found to occur throughout the whole observation period from March until November while Notiphila cinerea , Hydrellia ischiaca , and Psilopa nigritella appeared in a limited period only.  相似文献   

19.
Scattered Belongings: Cultural Paradoxes of "Race," Nation and Gender. Jayne O. Ifekwunigwe. New York: Routledge, 1999. 221 pp.
Race and Ideology: Language, Symbolism, and Popular Culture. Arthur K. Spears. ed. Detroit, MI: Wayne State University Press, 1999. 242 pp.
Spurious Issues: Race and Multiracial Identity Politics in the United States. Rainier Spencer. Boulder, CO: Westview Press, 1999. 222 pp.  相似文献   

20.
Synucleins comprise a family of small intracellular proteins that have recently attracted considerable attention because of their involvement in human diseases. Mutations of alpha-synuclein has been found in several families with hereditary early-onset Parkinson's disease and accumulation of this protein in characteristic cytoplasmic inclusions is a pathohistological hallmark of several neurodegenerative diseases that have been recently classified as 'alpha;-synucleinopathies' (reviewed in Brain Res. Bull. 50 (1999) 465; J. Neurosci. Res. 58 (1999) 120; Philos. Trans. R. Soc. Lond. Biol. Sci. 354 (1999) 1101; Brain Pathol. 9 (1999) 733). Aggregates of beta-synuclein and persyn (gamma-synuclein) also have been found in dystrophic neurites associated with Parkinson's and other neurodegenerative diseases (Proc. Natl. Acad. Sci. USA 96 (1999) 13450; and our unpublished observations). Moreover, persyn has been implicated in malignization of breast tumours (Cancer Res. 57 (1997) 759; Cancer Res. 59 (1999) 742; Hum. Mol. Genet. 7 (1998) 1417). All synucleins have distinct, although overlapping, patterns of expression in the embryonic, postnatal and adult mammalian nervous systems, suggesting important, although still not clear, biological functions in neuronal developing. Chicken embryo is a unique object for developmental studies that allows in vivo manipulations not always possible for mammalian embryos. Studies of synucleins expression in this model system could shed light on their functions in the developing nervous system. We cloned three chicken synucleins from the embryonic neural cDNA libraries and studied their expression in normal chicken embryonic tissues by Northern and in situ hybridization with specific probes. Our results demonstrate that primary structures and expression patterns of synucleins are similar in birds and mammals, suggesting that conserved function of synucleins is important for embryonic development of vertebrates.  相似文献   

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