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1.
Krishan Sharma 《HOMO》2014
The understanding of the role of genetic factors in phenotypic variation in the emergence of secondary teeth in humans remains is incomplete. Dental emergence data based on a mixed longitudinal study were collected on 111 twin pairs from an urban population of Chandigarh. The observations over time on a single individual varied from one to nine, thus giving a total of 595 entities. Female twins manifested emergence priority over males. The differences between zygosities in mean emergence ages were significant for only 6 of 16 (37%) instances. Magnitude of variations seen between twins and singletons in their mean emergence timings and duration of the hiatus between two dental phases of emergence were of the order observed among different samples from the same population/ethnic group. Heritability estimates for the specified number of the teeth emerged showed age variations. These estimates were highest in the first two age groups (from 5 to 7 years), when the first molars and incisors emerged. Maxilla-mandible differences were seen for tooth emergence timings and sequence patterns. Heritability for tooth emergence timings was higher in maxilla than in mandible. Multifactorial model of inheritance was the best fit model to explain variations observed in dental emergence timings and dental sequence pattern polymorphisms and there were significant genetic components of variation for both of these. There were sex differences in heritability; females had higher estimates than males. Genetic factors accounted for about 60% of the total phenotypic variation in the length of hiatus interval between two active stages of permanent teeth emergence. 相似文献
2.
For female workers in a computer factory in Japan, consisting of 41 daytime workers and 74 weekly-rotating shift workers (of whom, 37 each were engaged in, respectively, early-shift work and late-shift work during the survey week), within-day variations in the number of fatigue complaints were elucidated. Based on a repeated questionnaire survey, changes of fatigue complaints in a day were evaluated at three occasions, i.e., just before work, just after work, and before retiring, for three working days and one off day. The occasions of fatigue feelings differed among the three work groups: the complaints were significantly more frequent before work in the early-shift workers, after work in the late-shift workers, and before retiring in the daytime workers. Feeling of fatigue before and after work may be disadvantageous to safety and efficiency of work. 相似文献
3.
Objective: The aim of the study was to assess the uptake of dental services by the old and very old population within the scope of the Berlin Aging Study (Berliner Altersstudie BASE ). Design: A multi‐disciplinary structured interview was performed on 928 subjects, aged from 70 to 103 years of whom 516 persons volunteered to take part in a 14‐session intensive protocol. Six representative study groups were matched for age and gender. Subjects were asked to recall the timing of their most recent dental visit. Data were validated by sending for dental records and compared with all study participants from the multi‐disciplinary intake assessment. Data were related to age group, dental state, dementia and education. Results: Reported last contact with dental services ranged from 2 weeks to 52 years (median 18 months) with a higher time lapse in the study groups aged 85 and older. Dentate subjects had seen their dentist more recently than edentate subjects. Higher education correlated with an increased dental utilisation. Subjective memory on the time lapse since the last dental appointment coincided in 13% of the subjects with available dental records (n=84), was misjudged between one and six months in 55%, and by more than six months in the remainder. Moderately or severely demented subjects who remembered their last dental appointment (n=48 of 70) showed no consistently different utilisation to healthy or mildly demented studs participants. Conclusion: Edentate old and very old subjects show the least frequent utilisation of dental services. Data on motivation and barriers to care are needed to develop strategies to improve the use of dental services and thus promote oral health in late life. 相似文献
4.
A random sample of non-institutionalized elderly people in Örebro County, Sweden, has been examined. The present paper reports on the general health conditions obtained from interviews in this population and on the relation between general health and dental status. Eighty-one percent of the clinically examined subjects considered that they were healthy or fairly healthy. A higher percentage of women as compared to men regarded themselves to be moderately or very ill. Women also used more drugs than men did. Only 6% did not feel strong enough for extensive dental treatment. Physically handicapped people used dental services less than the rest of the population did. Otherwise, general health seemed to have limited influence on the use of dental services. Subjects with better dental status reported less frequent illness, chronic diseases, and medication as compared to subjects with poorer dental status. The self-assessed general health, also in the presence of age, sex, and residence variables, showed significant correlation with the dental status but not if socio-economic variables were also included in a regression model. 相似文献
5.
E D Shields B Altschuller E Y Choi M Michaud 《Journal of craniofacial genetics and developmental biology》1990,10(1):7-18
Quantified dental parameters (including root and pulp areas and shape variables) derived from periapical radiographs were used to make comparisons among a sample of American Black (8 males--124 teeth, 9 females--138 teeth), European derivative (31 males--304 teeth, 43 females--497 teeth) and Mongoloid populations (12 males--166 teeth, 19 females--252 teeth). The magnitude of sexual dimorphism within each ethnic stock was also examined. Teeth from American Black males were robust. Sexual dimorphism was unambiguous in all groups although a hierarchical order existed from the highly dichotomous American Black sample to the more homogeneous European sample. The female dental phenotype was down-scaled from their male counterparts, but not gracile in form. Easily obtained area and shape parameters derived from dental radiographs proved useful as discriminators among racial groups and the sexes. The relationships among these data lend further support to the hypothesis of an African origin of modern humans. 相似文献
6.
Suzanna Mihailidis Graham Scriven Mohd Khamis Grant Townsend 《American journal of physical anthropology》2013,152(1):19-30
We present new data on the prevalence and patterning of the maxillary premolar accessory ridge (MxPAR), a common but understudied morphological dental trait that is expressed as a linear elevation extending from the buccal cusp ridge to the medial sulcus of maxillary premolar teeth. A total of 579 sets of dental casts, representing six ethnic groups, were scored using the five‐grade system proposed by Burnett et al. (2010). The frequency and distribution of the MxPAR were determined by tooth type, sex, side, locus and ethnicity, and the applicability of the scoring system was assessed. The MxPAR was found in approximately two‐thirds of premolar teeth, more often on second than first premolars, and more often on the distal aspect of the occlusal surface than the mesial. There was some evidence that more pronounced forms of the feature occurred more often in males than females, and that there may be some directionality in its expression between sides. Variation was also noted in the frequency of occurrence and degree of expression of the MxPAR between ethnic groups. Intra‐ and inter‐observer concordance rates for scoring the MxPAR were low, confirming that it was difficult to score the trait identically on two different occasions. Our findings have clarified the distribution of the MxPAR within the dentition and between ethnic groups, and highlighted the need for researchers to carry out thorough replicability studies and to decide on an appropriate breakpoint for determining presence or absence of this feature before embarking on genetic studies or bio‐distance analyses. Am J Phys Anthropol 152:19–30, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
7.
To further explore economic relationships between patient age and dental practice productivity detected in previous studies, this study investigated the effects of variations in the mix of services used by different age groups on time and dollar-based dental practice outputs. Production function models for dental services were estimated using data from 31 Minnesota general dental practices reporting increased visits by older adults between June, 1980 and December, 1984. Analysis suggested that standardised time-based measures of productivity were not greatly affected by differences in the types of services used by different age groups. In contrast, differences in service mix between age groups exerted a substantial influence on dollar-based productivity that was independent of patient age. Overall, dental practices were less productive with older patients, but the decline in monetary productivity was not evident until patient age was disaggregated from differences in service use by different age groups. 相似文献
8.
C L Lavelle 《American journal of physical anthropology》1977,46(3):415-421
Sixteen dimensions were measured from the maxillary and mandibular dental arches of different ethnic groups of man, apes and monkeys. Multivariate analysis showed that discrimination was possible among the ethnic groups of man on the one hand and between the ape and monkey samples on the other. Nevertheless, the actual degree of discrimination between the primate samples depended upon whether the maxillary or mandibular arch dimensions were analysed. Furthermore, subsequent inclusion of the dental arch dimensions of fossil hominoid samples into the analysis confirmed the taxonomic significance of the dental arch, although its importance must await the acquisition of the more non-human primate data. 相似文献
9.
To determine the prevalence of use of traditional health practices among different ethnic groups of Southeast Asian refugees after their arrival in the United States, we conducted a convenience sample of 80 Cambodian, Lao, Mien, and ethnic Chinese patients (20 each) attending the University of Washington Refugee Clinic for a new or follow-up visit. Interpreters administered a questionnaire that dealt with demographics, medical complaints, traditional health practices, health beliefs, and attitudes toward Western practitioners. In all, 46 (58%) patients had used one or more traditional health practices, but the prevalence varied by ethnic group. Coining and massage were used by all groups except the Mien, whereas moxibustion and healing ceremonies were performed almost exclusively by the Mien. Traditional health practices were used for a variety of symptoms and, in 78% of reported uses, patients reported alleviation of symptoms. The use of traditional health practices is common among Southeast Asian refugees. Clinicians who care for this population should be aware of these practices because they may supersede treatments prescribed by physicians or leave cutaneous stigmata that may be confused with disease or physical abuse. Good patient care may necessitate the use or tolerance of both Western and traditional modalities in many Southeast Asian refugees. 相似文献
10.
The pattern of psychiatric consultation in Hong Kong is examined among 226 patients at a public outpatient clinic and 56 patients at a private psychiatric clinic. The approach to psychiatric services is marked by lengthy delay during which patients get help from their family members or close friends. Arrival at the present psychiatric clinic was diverted through other medical resources, primarily Western-style medical services, and to some extent, traditional Chinese medicine. Individual routes were diverse, characterized by frequent switches among resources especially in the private sector. The nature of the patients' presenting complaints as well as the conceptualization of their initial complaints were multi-faceted, including both psychological and somatic factors. The overall consultation pattern of patients in Hong Kong is compared with other studies on Chinese and Western patients. Questions are raised for further analysis.The study was funded by the United Board for Christian Higher Education in Asia Faculty Research Grant made through Chung Chi College of The Chinese University of Hong Kong. 相似文献
11.
Donald H. Minkler Carol Korenbrot Claire Brindis 《The Western journal of medicine》1988,148(3):349-354
Five different Southeast Asian groups were studied to document family planning knowledge, attitudes, and practices, and to identify current barriers to care. Significant differences exist among ethnic groups in their knowledge and use of effective methods of contraception, as well as variations in the timing of when to adopt family planning practices and in the preferred number of children. Nearly 70% of the sample had experienced barriers to services, including language, transportation, and a lack of awareness of available services. 相似文献
12.
Factors contributing to differences in the prevalences of respiratory symptoms and diseases among ethnic groups were studied in primary schoolchildren living in 20 inner city areas of England in 1983. The raised prevalences of respiratory symptoms in these groups were compared with results from a national representative sample of children studied in 1982. Data on age, sex, respiratory illness, and social and environmental variables were obtained by questionnaire for 4815 children living in inner cities. The children were classified as white, Afro-Caribbean, Urdu, Gujarati, Punjabi, other Asian, or “other.” Significant differences in the prevalence of respiratory conditions were found among the ethnic groups after allowance was made for the effects of interfering variables. Except for asthma all conditions were most prevalent in Afro-Caribbeans and whites. In these two ethnic groups respiratory illness was significantly associated with belonging to a one parent family and the combined use of gas cookers and paraffin heaters at home.Respiratory illness was found to vary in prevalence among ethnic groups but may be perceived differently by different groups. Further studies, measuring lung function, are necessary. 相似文献
13.
The aim of this study was to describe dental state, oral health problems, self-assessed ability to perform oral hygiene and utilization of oral health services in a sample of 88-year-old people (n=374) and to relate these variables to functional ability, subjective health and drug consumption. The intention was also to Identify barriers to utilization of dental care in non-institutionalized elderly people. The results of interviews showed that 46% of the subjects were dentate. Oral complaints were reported by 24% of the home living individuals. Poor health, medication and feelings of loneliness were factors associated with oral discomfort. Difficulties in performing oral hygiene activities were reported by 10% of the subjects and were correlated with functional impairments and feelings of loneliness. Utilization of dental services was correlated with dental state; 72% of the dentate and 8% of the edentulous subjects made regular dental visits. The main reason for not visiting a dentist was “no perceived need”. Independent of dental state, some factors were significantly correlated to low demand for dental services; these included feelings of loneliness, functional impairments and low school education. 相似文献
14.
Débora Dias Da Silva Lilian Berta Rihs Maria Da Luz Rosário de Sousa 《Gerodontology》2020,37(3):288-296
Objectives: The objective of this study was to verify the association between the number of teeth present with socio-demographic and economic variables and with the access to dental services and self-perception of oral health among the elderly. Materials and Methods: The sample was composed of individuals from 65 to 74 years of age, which was representative of the state of São Paulo (n = 781). In this study, the analysis of data considered dentate elderly only, who were divided into two groups: those with one to 19 teeth and those with 20 teeth or more. The chi-squared test was used in the bivariate analysis and the logistic regression was also performed (p < 0.05). Results: Among the 313 dentate elderly, 235 (75.1%) presented one to 19 teeth. The average number of teeth was 9.5 for the elderly with fewer teeth and 25 for those with more teeth. In the bivariate analysis, all variables related to the access to dental services were associated and the chances of having less teeth was among elderly who did not visit the dentist for a long time and among those who sought public dental services and did not receive information on how to avoid oral problems. In addition, the elderly who classified their speech as not good were those who presented with fewer teeth. Conclusion: Most subjects presented one to 19 teeth and this fact was directly associated, among others factors, to the unsatisfactory perception that they reported in relation to their speech and to the too long period without visiting the dentist. 相似文献
15.
The present paper examines dental diseases and linear enamel hypoplasia among the Garamantes, a Late Holocene Saharan population, and aims to draw conclusions about nutrition and adaptation to a hyper-arid environment. Archaeological evidence suggests that the Garamantian diet included animal protein and local, Mediterranean and Near Eastern plants. Moreoever, although the Garamantes had developed urban centres, the size of these was not large enough to allow for particularly unhygienic conditions to appear. The above archaeological findings were partly corroborated by the current bioarchaeological study. At an intra-population level, the Garamantes showed limited sex differences in dental disease prevalence, while all dental conditions increased in frequency with age, as expected. At an inter-population level, the frequency of all dental conditions was comparable to that found among other North African groups, with the exception of ante-mortem tooth loss. The low frequency of most dental conditions is an indication that the Garamantian diet was overall balanced, while the high frequency of ante-mortem tooth loss may be related to factors such as oral hygiene, food preparation or eating mode, which cannot be controlled for osteologically. Finally, the low frequency of enamel hypoplasia suggests either that the Sahara did not inflict particular stresses on the population, or, more likely, that the Garamantes had developed effective mechanisms for coping with their natural environment. 相似文献
16.
Khaliq S Hameed A Khaliq T Ayub Q Qamar R Mohyuddin A Mazhar K Qasim-Mehdi S 《Genetic testing》2000,4(1):23-29
Inactivation of the p53 gene has been found to be associated with the pathogenesis of several neoplasias. Three biallelic polymorphisms in the p53 gene have been linked to predisposition to the development of various malignancies. These include a 16-bp duplication in intron 3 and BstU I and Msp I restriction fragment length polymorphisms (RFLPs) in exon 4 and intron 6, respectively. The prevalence of these polymorphisms was studied in breast cancer patients and nine major ethnic groups of Pakistan. Differences in allele frequencies for all three polymorphisms were observed among the various ethnic groups and breast cancer patients. The absence of the 16-bp duplication was common among the northern ethnic groups, being highest in the Hazara (0.90). The Msp I A1 allele frequency in the southern Makrani population was significantly higher in comparison with the other ethnic groups. In the cancer patients, the absence of the 16-bp duplication in combination with the BstU I Pro and absence of Msp I restriction site were the most frequent. In these patients, ten substitution mutations were found in the p53 gene, seven of which have been reported previously for breast cancer. The remaining three mutations have been found in other malignancies, but not in carcinoma of the breast. 相似文献
17.
18.
Data are presented on dental and general health for seven groups of wild ring-tailed lemurs, Lemur catta, from the Beza Mahafaly Reserve, in southern Madagascar. As part of a study of population demography, adults were captured, collared, and tagged, and biometric measurements, dental casts, and analyses of dental and general health were made. Results indicate that patterns of dental health vary by individual, age, sex, and habitat. Prime adults show more dental attrition than young adults. Prime males living in more marginal habitats show greater mean attrition than those living in richer habitats. Dental damage, specifically to the toothcomb, indicates that mechanical stresses to this region may include the initial harvesting of foods, in addition to grooming. Males exhibit more evidence of past trauma, including scars and chipped teeth. These results indicate that environmental as well as social factors, such as female dominance, may lead to sex differences in health patterns among lemurs. 相似文献
19.
Silke Hauer 《Acta theriologica》2002,47(3):339-362
A sample of 1037 skulls of ottersLutra lutra (Linnaeus, 1758) from eastern Germany was analysed for inherent dental abnormalities. Deviations from the normal dental pattern
were found in 107 individuals. A total of 150 cases were classified in 5 categories of abnormality. In considering variations
from the normal number of teeth, supernumerary (polydonty, 1.7%) was more frequent than missing teeth (oligodonty, 0.9%).
In most cases, numerical variations were not connected with phylogenetic background. The most frequent variations were displacement
of teeth in the tooth row (6.0%) and deviations of the normal shape of teeth (3.3%). Variations of the local position of teeth
occurred in 2.6% of cases. None of these deviations showed significant sex-dependent differences. Furthermore, no regional
differences in the frequencies of these anomalies were noticed. Another 459 otters (822 cases) had accessory roots at P2,
P3, or P4. These characters were considered as non-metrical traits and used to study epigenetic regional differentiation.
The Mean Measure of Divergence segregated the Baltic coast from almost all other regions. Preliminary results of analysis
of Fluctuating Asymmetry are presented, using these traits to demonstrate the utility of dental deviations for estimating
influences on developmental stability. Generally, it can be stated that the dentition of otters is very stable. 相似文献
20.
The frequency of aneuploidy among individual chromosomes in 6,821 human sperm chromosome complements 总被引:7,自引:0,他引:7
The human sperm/hamster egg fusion technique has been used to analyse 6,821 human sperm chromosome complements from 98 men to determine if all chromosomes are equally likely to be involved in aneuploid events or if some chromosomes are particularly susceptible to nondisjunction. The frequency of hypohaploidy and hyperhaploidy was compared among different chromosome groups and individual chromosomes. In general, hypohaploid sperm complements were more frequent than hyperhaploid complements. The distribution of chromosome loss in the hypohaploid complements indicated that significantly fewer of the large chromosomes and significantly more of the small chromosomes were lost, suggesting that technical loss predominantly affects small chromosomes. Among the autosomes, the observed frequency of hyperhaploid sperm equalled the expected frequency (assuming an equal frequency of nondisjunction for all chromosomes) for all chromosome groups. Among individual autosomes, only chromosome 9 showed an increased frequency of hyperhaploidy. The sex chromosomes also showed a significant increase in the frequency of hyperhaploidy. These results are consistent with studies of spontaneous abortions and liveborns demonstrating that aneuploidy for the sex chromosomes is caused by paternal meiotic error more commonly than aneuploidy for the autosomes. 相似文献