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1.
Jingze Tan Yajun Yang Kun Tang Pardis C. Sabeti Li Jin Sijia Wang 《Human genetics》2013,132(10):1187-1191
Hair straightness/curliness is a highly heritable trait amongst human populations. Previous studies have reported European specific genetic variants influencing hair straightness, but those in East Asians remain unknown. One promising candidate is a derived coding variant of the ectodysplasin A receptor (EDAR), EDARV370A (370A), associated with several phenotypic changes of epidermal appendages. One of the strongest signals of natural selection in human genomes, 370A, has risen to high prevalence in East Asian and Native American populations, whilst being almost absent in Europeans and Africans. This striking frequency distribution and the pleiotropic nature of 370A led us to pursue if hair straightness, another epidermal appendage-related phenotype, is affected by this variant. By studying 1,718 individuals from four distinctive East Asian populations (Han, Tibetan, Mongolian, and Li), we found a significant association between 370A and the straight hair type in the Han (p = 2.90 × 10?6), Tibetan (p = 3.07 × 10?2), and Mongolian (p = 1.03 × 10?5) populations. Combining all the samples, the association is even stronger (p = 5.18 × 10?10). The effect of 370A on hair straightness is additive, with an odds ratio of 2.05. The results indicate very different biological mechanisms of straight hair in Europe and Asia, and also present a more comprehensive picture of the phenotypic consequences of 370A, providing important clues into the potential adaptive forces shaping the evolution of this extraordinary genetic variant. 相似文献
2.
研究维吾尔人利用植物的传统知识和经验,在社会经济发展和资源保护等方面具有潜在的应用价值。胡杨(Populus euphratica Oliv.)和灰叶胡杨(P.pruinosa Schrenk)是新疆沙漠生态系统的主要植物类群,研究采用关键人物访谈法,对胡杨和灰叶胡杨在新疆尉犁县维吾尔族民间的植物文化进行了研究。结果表明:胡杨和灰叶胡杨的胡杨碱白色结晶体在治疗胃胀、咽喉肿痛、胃溃疡、十二指肠溃疡及消化不良等方面有作用;胡杨碱黑色结晶体用于治疗腰疼、腿疼,有消肿及止痛等疗效;胡杨碱加工后作洗发膏和洗衣粉使用;胡杨水不仅治疗神经衰弱,有延缓衰老、降低高血压及高血脂的功效,还能降低心脏病发病率;胡杨和灰叶胡杨枝叶具有治疗家畜胃胀和肌胃腐烂病的作用。当地罗布人利用胡杨树来建设沙漠生态园及控制土壤沙漠化。研究初步揭示了两种胡杨植物与维吾尔人的植物文化体系,维吾尔族植物传统知识的研究,将对我国民族植物学的发展及多样性产生影响。 相似文献
3.
趾长比是指动物不同趾长的比值,常被认为是早期雄激素或雌激素暴露的标记物之一.本文通过测量新疆敏麻蜥Eremias arguta 3个地理种群的雌雄成体各趾长并计算趾长比,探究不同地理种群趾长及趾长比的两性差异.结果表明,伊犁地区雄性后肢的第2趾显著大于雌性(P<0.05);富蕴县雄性前肢、后肢的第2、3、4、5趾长均显... 相似文献
4.
doi: 10.1111/j.1741‐2358.2011.00465.x A cross‐sectional analysis of the prevalence of dental anxiety and its relation to the oral health‐related quality of life in patients with dental treatment needs at a university clinic in Switzerland Objectives: The aim of this observational, cross‐sectional study was to analyse the relationship between dental anxiety (DA) and health‐related quality of life aspects associated with oral conditions of a population with dental treatment needs in Switzerland. Methods: The measurements of DA were collected by means of two questionnaires, the Dental Anxiety Scale (DAS) and a Visual Analogue Scale (VAS). Oral health‐related quality of life (OHRQoL) was assessed with the Oral Health Impact Profile (OHIP). The sample included 223 patients enrolled at a university clinic which specialises in oral prosthetic rehabilitation and temporomandibular disorders. Of them, 78.9% were at or above the age of 50. Results: No gender or age dependencies were observed. A comparison of answers regarding OHRQoL and DA revealed a significant interdependence (p = 0.0118); highly anxious patients were 3.55 times more likely to suffer from poor quality of life compared with less anxious ones. Conclusion: This cross‐sectional study of mostly elderly patients seeking dental treatment in Switzerland found that increased DA was associated with an impaired OHRQoL. The average DA was slightly higher than the results of other industrialised countries and the average OHRQoL was reduced. 相似文献
5.
新疆特有种植物区系及生态学研究 总被引:8,自引:0,他引:8
经调查新疆特有植物约有 2 6 8种 ,隶属 38科 119属。由于新疆特有种贫乏 ,其分布多集中于新疆主要山系。因此 ,应把它们作为生物多样性保护的关键种和敏感区倍加关注。多年生植物在新疆特有植物中占多数 ,显示了物种形成的年轻成分 ,这与新疆的气候环境比较严酷有一定的关系。也反映了新疆地区远离中国特有中心的特点。从一个侧面也反映了新疆地质历史和区系发展历史的特点 ,研究植物的特有现象 ,可为深入了解新疆植物区系的性质、特点、起源及演变规律提供资料。 相似文献
6.
新疆梅衣属地衣生态地理特征分析 总被引:2,自引:0,他引:2
根据多年的实地调查资料和相关研究资料,对新疆梅衣属(Parmelia Ach.)地衣的种类及分布区、区系特征和垂直分布特征进行了初步研究。结果表明,分布在新疆的梅衣属地衣共有6种,分别为破裂梅衣(Parmelia erumpens Kurok.)、稀生梅衣(P.meiophora Nyl.)、脐梅衣[P.omphalodes(L.)Ach.]、石梅衣[P.saxatilis(L.)Ach.]、槽梅衣(P.sulcata Tayl.)和亚广开梅衣(P.fertilis Muell.),主要分布在新疆的天山和阿勒泰山。根据对环境的适应特征和选择性,将新疆梅衣属地衣的地理分布区类型划分为:1)环低北极及北方种,包括石梅衣和脐梅衣2种;2)环北方种,包括槽梅衣和稀生梅衣2种;3)温带亚洲种,包括亚广开梅衣和稀生梅衣2种。研究结果还显示,分布在阿勒泰山和天山的梅衣属种类的垂直分布有明显差异。 相似文献
7.
采用样地法对新疆托木尔峰国家级自然保护区岩面生地衣群落的种类组成进行调查和统计,并以各种类的盖度为指标、应用双向指示种分析( TWINSPAN)和除趋势对应分析( DCA)对岩面生地衣群落进行数量分类;采用S?rensen相似性系数分析各群丛的物种相似性;此外,应用典范对应分析( CCA)探讨了岩面生地衣种类分布与环境因子间的关系。结果表明:该保护区岩面生地衣群落共包含58种地衣,隶属于6目18科35属;优势科有5个,包含的属、种数量分别占该保护区岩面生地衣属、种总数的42.86%和62.07%。依据TWINSPAN和DCA分析结果并结合生境特征,可将该保护区岩面生地衣群落划分为5个群丛:群丛 A,包氏微孢衣+双缘衣群丛( Assoc. Acarospora bohlinii+Diploschistes scruposus);群丛 B,油黄茶渍+亚白平茶渍+柔扁枝衣群丛( Assoc. Candelariella oleifera+Aspicilia subalbicans+Evernia divaricata);群丛C ,斑纹网衣+旱梅衣+淡肤根石耳群丛( Assoc. Lecidea tessellata+Parmelia vegans+Umbilicaria verginis);群丛D,丽石黄衣+白泡鳞衣群丛( Assoc. Xanthoria elegans+Toninia candida);群丛E,皮果衣+硬袋衣群丛( Assoc. Dermatocarpon miniatum+Hypogymnia austerodes)。相似性分析结果表明:群丛A与群丛B、群丛C与群丛D间的物种相似性较高,相似性系数分别为0.615和0.733;群丛B与群丛C间的物种相似性次之,相似性系数为0.363;其他群丛间的物种相似性均较低。 CCA分析结果显示:该保护区岩面生地衣群落的物种分布受到海拔、光照强度、岩面pH值和相对湿度的影响。 相似文献
8.
新疆中天山野生种子植物区系分析 总被引:1,自引:0,他引:1
基于野外调查,采集植物标本以及对相关文献资料进行整理,构建中天山野生种子植物名录,在此基础上对该地区野生种子植物区系进行分析.结果表明:(1)中天山地区共有野生种子植物81科453属1 567种;(2)优势科有菊科、禾本科、豆科、十字花科、唇形科、毛茛科等17科,表征科有石竹科、莎草科、百合科、茜草科、龙胆科、禾本科、蓼科等7科;(3)区系地理成分以温带分布型为主,其中科级水平上,温带分布型所属科共有36科,占到总科数(不含世界广布科)的76.60%.属级水平上,温带性质分布型的属有377属,占总属数的94.96%.同时该地区植物物种与地中海、中亚、西亚交流相对较多,与东亚交流很少. 相似文献
9.
Study on the relationship between Helicobacter pylori in the dental plaque and the occurrence of dental caries or oral hygiene index 总被引:1,自引:0,他引:1
Background: The aims of our study were to determine the presence of Helicobacter pylori DNA in the dental plaque of Chinese children aged 3–6 years by nested polymerase chain reaction (PCR) and to investigate the relationship between this infection and the occurrence of dental caries or oral hygiene index.
Methods: Two hundred and fourteen children from a kindergarten in Guangzhou City of China were evaluated. The children's plaques were assessed by plaque indices of Quigley–Hein. Dental plaque was analyzed using nested PCR for two sets of primers directed to the 860-bp fragment of H. pylori genomic DNA, which have been reported to be highly sensitive and specific by other researchers.
Results: H. pylori was detected in dental plaque samples from 126 children, and 70 children with dental caries carried H. pylori in dental plaque. Of these children without infection, only 36 of 88 suffered dental caries. Besides, the average dental plaque index of 126 H. pylori -positive children was higher than that of 88 children without infection. In the present study, there was a significant correlation between H. pylori infection and dental caries or dental hygiene.
Conclusion: The oral cavity may be a reservoir for H. pylori infection in children. H. pylori in dental plaque may play a role in the occurrence of dental caries, and poor oral hygiene may represent a risk factor for H. pylori in the oral cavity. 相似文献
Methods: Two hundred and fourteen children from a kindergarten in Guangzhou City of China were evaluated. The children's plaques were assessed by plaque indices of Quigley–Hein. Dental plaque was analyzed using nested PCR for two sets of primers directed to the 860-bp fragment of H. pylori genomic DNA, which have been reported to be highly sensitive and specific by other researchers.
Results: H. pylori was detected in dental plaque samples from 126 children, and 70 children with dental caries carried H. pylori in dental plaque. Of these children without infection, only 36 of 88 suffered dental caries. Besides, the average dental plaque index of 126 H. pylori -positive children was higher than that of 88 children without infection. In the present study, there was a significant correlation between H. pylori infection and dental caries or dental hygiene.
Conclusion: The oral cavity may be a reservoir for H. pylori infection in children. H. pylori in dental plaque may play a role in the occurrence of dental caries, and poor oral hygiene may represent a risk factor for H. pylori in the oral cavity. 相似文献
10.
Objectives: This study reports findings on the dental status and the prevalence of dental caries among a group of 85‐year‐old Danes from the Glostrup 1914 Cohort, Denmark. The purpose of the study was to analyse whether caries experience was related to number of teeth and to indicators of functional ability and cognitive function. Methods: A total of 191 individuals (78 men and 113 women) participated in a cross‐sectional population study conducted in 2000. Using mobile dental equipment, a clinical oral examination and an interview were administered to all participants in their homes. Functional ability was measured by the Mob‐H scale and cognitive function was assessed by the Mini‐Mental State Examination. Results: Fifty‐nine per cent of the participants had their own natural teeth and for the dentate participants, the mean number of teeth was 13 (range 1–27). A high prevalence of active caries on coronal and root surfaces was observed. Older adults with few natural teeth had a higher prevalence of active coronal and root caries and a higher unmet treatment need than older adults with many teeth. Further, the study showed that 85‐year‐old persons with reduced functional ability and cognitive impairment tended to have more active caries than 85‐year‐olds with no impairment. Conclusions: A substantial proportion of 85‐year‐old individuals had retained a natural dentition; however, active dental caries is a problem of concern among the most elderly. 相似文献
11.
Objectives: To describe the initial dental treatments of Lithuanian dentate elderly patients and the content of the most recent treatment in relation to their dentist‐visiting behaviour. Materials and methods: A cross‐sectional questionnaire study was carried out at two public dental offices in Kédainiai, Lithuania, among dentate patients aged 60+ years. A self‐administered questionnaire covered first‐time dental care, the most recent dental treatment, check‐up behaviour, interval since the most recent dental visit, and number of teeth. Age, gender and education served as background information. Statistical evaluation was by chi‐squared test, anova and logistic regression for odds ratio (OR). Results: In all, 174 dentate elderly responded, mean age being 69.2 (SD = 6.6) years. The mean age at the first visit was 16.3 years [95% confidence interval (CI) 14.9–17.6]. Regular dental check‐ups were reported by 30%, and 36% had visited a dentist within the past 12 months. As to the content of the most recent treatment, 78% of the elderly reported filling therapy, 50% endodontics, 48% tooth extraction, 21% radiography, 10% cleaning or scaling and 6% polishing of fillings. Those going for check‐ups were more likely to report diagnostic (OR 1.9; 95% CI 1.1–2.8; p = 0.01) and preventive (OR 4.8; 95% CI 2.5–9.0; p = 0.002) treatment when analysed by a logistic regression model, controlling for age, gender, education and number of teeth. Conclusions: Check‐up‐orientated utilisation of dental services should be encouraged among the Lithuanian elderly. Dentists and health officials should place greater emphasis on prevention. 相似文献
12.
新疆药用资源植物及其开发利用现状 总被引:9,自引:0,他引:9
为使新疆药用植物研究在开发利用中更具现实意义,本文通过调查和文献资料查阅总结出新疆主要药用植物种类、主要药用植物资源量及药效、药用植物研究已完成的工作及研究现状。由此提出对新疆药用植物开发利用的几点建议,以利于更好地对新疆药用植物的保护、开发及利用。 相似文献
13.
Zdzislaw Artur Bogucki 《Gerodontology》2013,30(2):162-166
doi: 10.1111/j.1741‐2358.2012.00659.x Clinical aspects of the use of dental adhesive materials in patients with chronic xerostomia Adhesives are commonly used by denture wearers to increase the retention and stability of the complete denture, to improve the chewing and masticatory abilities and to psychologically support the patient to make the complete denture more acceptable. Denture fixatives can be especially recommended for use and to aid retention for patients with dryness of the mouth, poor secretion of saliva and xerostomia (e.g. diabetes mellitus). Dental adhesives may be contaminated with bacteria, yeast and fungi during the manufacturing process, and they have been shown to initiate and promote microbial growth. Some products have been shown to release formaldehyde, which is cytotoxic to cell culture and fibroblasts and is a potent allergen. Patients with chronic xerostomia may use denture adhesives during the course of the treatment and disease. These patients are often immunocompromised, and microorganisms they are exposed to must be considered potential pathogens. 相似文献
14.
Frederick H. Kasten Susan M. Felder Lawrence Gettleman Thomas Alchediak 《In vitro cellular & developmental biology. Plant》1982,18(7):650-660
Summary A model experimental culture system and protocol are described to screen polymerized dental materials for diffusible toxic
products. The system employs cultures of human gingival fibroblasts grown in plates containing immobilized samples of polymerized
resins. Comparative cytotoxicity is evaluated by counting viable cells with the aid of phase optics at several time periods
up to 48 h. To achieve adequate statistical sampling, multiple counts are made in four different zones at 90° angles from
each sample and at three distances from the centers of samples. The most significant data were generated during a 24 to 48
h test period in culture. This cytotoxicity test measured cell death as a function of time of exposure and distance from the
sample (24 h, 0 to 3 mm; 48 h, 3 to 6 mm) and permitted a calculation of the relative cytotoxicity for each material, which
is termed the viability index (VI). This can be expressed as a percentage related to the control, which is called the time-distance
cytotoxicity index (TDCI). This method is simple to carry out because it uses basic laboratory equipment, is rapid, and has
a sound scientific basis. It focuses on times and distances when or where, or both, the greatest cellular changes are taking
place. Some data illustrated are based on the screening of eight different restorative resins. The literature of cell culture
testing of dental materials is reviewed.
It is concluded that biotoxicity studies ideally should employ diploid human target cells from the oral cavity because the
cells retain specialized features. Secondary cultures or strains of human diploid gingival fibroblasts, which are relatively
easy to obtain and maintain, are recommended as cells of choice for screening dental restorative materials in vitro.
This project was supported in part by an intramural grant from the Louisiana State University School of Dentistry, derived
from BRSG Grant S07-RR-05704-10 awarded by the Biomedical Research Grant Program, Division of Research Resources, National
Institutes of Health, Bethesda, MD. 相似文献
15.
Objective: The aim of the study was to reveal barriers to providing dental care for residents in long‐term care (LTC) facilities. Design: Participants were selected randomly from the dentist register in Berlin and Saxony, Germany. The sample consisted of 60 self‐employed and 60 employed dentists, a further 60 dentists worked in their own dental practice but also part‐time in an LTC facility. In semi‐structured interviews a questionnaire with 36 statements concerning working conditions, administration and cost, insecurity concerning treatment decisions as well as confrontation with ageing and death was employed. Subsequently, the study participants were asked to rank the four dimensions concerning their impact on the decision against providing dental care in an LTC facility. Results: The random sample was representative in age and gender for the dental register in Berlin and Saxony. Fifty‐six per cent of the participants (63% of the men and 51% of the women; 52% of the self‐employed, 60% of the employed and 56% of the consultant dentists) indicated unfavourable working conditions as biggest obstacle in providing dental care in an LTC‐facility. Thirty‐two per cent of participants rated administration and cost, 7% the insecurity in treatment decisions as major hindrance. Only 5% of the participants rated the confrontation with age and death as substantial barrier. There were no age and gender differences. Dentists in Berlin seemed more concerned about administration and cost of a consultancy activity and less secure in their therapy decisions than the colleagues from Saxony (p < 0.001). Dentists who work partly in LTC facilities were the least concerned about the confrontation with ageing and death (not significant), employed dentist showed the least secure in their treatment decisions (p > 0.001). Conclusion: It can be concluded that the awareness of infra‐structural and financial aspects in providing dental care in LTC facilities should be raised with health politicians and that these aspects should be considered when inaugurating or re‐structuring the consultancy services to LTC facilities. Further it would be desirable to establish more postgraduate training programmes to increase clinical and ethical competence in the area of gerodontology. 相似文献
16.
Andrea M.C. Joaquim Chris C.L. Wyatt Jolanta Aleksejūnienė Sebastiao L.A. Greghi Luiz F. Pegoraro H. Asuman Kiyak 《Gerodontology》2010,27(4):258-265
doi: 10.1111/j.1741‐2358.2009.00340.x A comparison of the dental health of Brazilian and Canadian independently living elderly Objective: To compare the dental status of Brazilian and Canadian elderly populations with respect to socioeconomic and quality of life factors. Materials and methods: A total of 496 adults aged 60–75 years, having four or more teeth, and physically and cognitively suitable for a clinical oral examination were included. Subjects answered questions concerning their lifestyle and completed the Geriatric Oral Health Assessment Index (GOHAI) questionnaire. Results: In all populations, the majority were females, aged between 60 and 65 years and married. Although the Canadian New Immigrant population had lower mean income, they had more remaining teeth (23.04 ± 6.1), more functional teeth (sound and restored teeth) (14.92 ± 5.7), more sound teeth (15.40 ± 7.6), but more carious teeth (2.97 ± 3.0). The Brazilian population had higher numbers of restored teeth (12.26 ± 6.8) and fewer remaining teeth (17.80 ± 7.6). In all populations, females, married and younger (60–65 years old) adults were more likely to retain 20 or more teeth. The mean GOHAI scores were similar for Canadians (40.55 ± 5.7) and Canadian New Immigrants (39.28 ± 6.5), but were higher than that among Brazilians (31.97 ± 8.9). Conclusions: The numbers of remaining teeth were related to greater education and higher income status for Brazilian and Canadian populations. However, Canadian New Immigrants with lower income and education retained more teeth than the other populations. 相似文献
17.
采用常规压片法,对从新疆采集的5份疏花蔷薇进行了核型分析.结果表明:疏花蔷薇包括二倍体(2n=2x=14)和四倍体(2n=4x=28)两种核型;核不对称系数为55.14%~60.11%;核型分类包括1A、2A、1B等3种类型;分析认为,不同倍性的出现与种质在不同区域、不同生境下生长有一定相关性.其中疏花蔷薇5号为四倍体,核型信息与其他材料差异明显,核不对称系数最大,核型分类也最进化.研究结果支持刘士侠等对其表型分类的划分,即托木尔蔷薇作为疏花蔷薇在新疆的特殊地理种;而4号材料也支持《新疆植物志》的分类,即建议喀什疏花蔷薇作为疏花蔷薇的变种. 相似文献
18.
Familial hypercholesterolemia (FH) is a disease implicated with defects in either, Low density lipoprotein receptor gene (LDLR), Apolipoprotein B-100 gene (APOB), the Proprotein convertase subtilisin/kexin type 9 gene (PCSK9) or other related genes of the lipid metabolism pathway. The general characterization of heterozygous FH is by elevated low-density lipoprotein (LDL) cholesterol and early-onset cardiovascular diseases, while the more severe type, the homozygous FH results in extreme elevated levels of LDL cholesterol and usually death of an affected individual by early twenties. We present here a novel non-synonymous, missense mutation in exon 14 of the LDLR gene in two siblings of the Malay ethnicity discovered during an in-house genetic test. We postulate that their elevated cholesterol is due to this novel mutation and they are positive for homozygous FH. This is the first report of a C711Y mutation in patients with elevated cholesterol in Asia. 相似文献
19.
Tamazawa Y Watanabe M Kikuchi M Takatsu M Tamazawa K Yumoto N Hyvarinen P 《Gerodontology》2004,21(1):53-59
Objective: To develop a dental unit to accommodate both patients in wheelchairs and general patients, and to evaluate the acceptability of the new chair for patients and dentists. Design: To integrate a unit for patients in wheelchairs and a unit for general patients into a single dental unit. Results: (1) The newly developed dental unit could be used for both patients in wheelchairs and general patients and could be installed in nearly the same space as occupied by a conventional dental unit. (2) The dentists could take the home position because of the height‐adjusting and tilting mechanisms. (3) The patients could be treated with a sense of assurance because of the wheelchair immobilizer and the safety devices. (4) The dentists could perform patient treatment safely. (5) As patients did not need to be transferred from their wheelchairs, assistance was unnecessary. (6) From the questionnaires, both patients and dentists rated the newly developed dental unit favourable. Conclusions: The new dental unit for patients in wheelchairs and general patients permitted dentists to perform and patients to receive dental treatment safely and in a comfortable position. Also, as a single unit could be used for treatment of both types of patients, it required no extra space. Therefore, it has the potential to be installed in the clinics of general dental practitioners to treat both groups of patients. 相似文献
20.
B. Holly Smith Stanley M. Garn Patricia E. Cole 《American journal of physical anthropology》1982,58(3):281-289
Randomly distributed or “fluctuating” dental asymmetry has been accorded evolutionary meaning and interpreted as a result of environmental stress. However, except for congenital malformation syndromes, the determinants of human crown size asymmetry are still equivocal. Both a computer simulated sampling experiment using a combined sample size of N = 3000, and the requirements of adequate statistical power show that sample sizes of several hundred are needed to detect population differences in dental asymmetry. Using the largest available sample of children with defined prenatal stresses, we are unable to find systematic increases in crown size asymmetry. Given sampling limitations and the current inability to link increased human dental asymmetry to defined prenatal stresses, we suggest that fluctuating dental asymmetry is not yet established as a useful and reliable measure of general stress in human populations. 相似文献