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1.
Inference of biogeographic origin is an important factor in clinical, population and forensic genetics. The information provided by AIMs (Ancestry Informative Markers) can allow the differentiation of major continental population groups, and several AIM panels have been developed for this purpose. However, from these major population groups, Eurasia covers a wide area between two continents that is difficult to differentiate genetically. These populations display a gradual genetic cline from West Europe to South Asia in terms of allele frequency distribution. Although differences have been reported between Europe and South Asia, Middle East populations continue to be a target of further investigations due to the lack of genetic variability, therefore hampering their genetic differentiation from neighboring populations. In the present study, a custom-built ancestry panel was developed to analyze North African and Middle Eastern populations, designated the ‘NAME’ panel. The NAME panel contains 111 SNPs that have patterns of allele frequency differentiation that can distinguish individuals originating in North Africa and the Middle East when combined with a previous set of 126 Global AIM-SNPs. 相似文献
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Monolayer cultures of normal human bone cells contain multiple subpopulations of alkaline phosphatase positive cells 总被引:5,自引:0,他引:5
Toshikatsu Matsuyama K. -H. William Lau Jon E. Wergedal 《Calcified tissue international》1990,47(5):276-283
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures
contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative
cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical
method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method,
human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We
defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and
intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values
at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations,
were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels
in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the
intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and
IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with
the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated
with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation.
In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least
two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population. 相似文献
5.
Kim Mudd Mary Elizabeth Bollinger Van Doren Hsu Michele Donithan Arlene Butz 《The Journal of asthma》2006,43(8):597-600
Background. Medication adherence impacts healthcare utilization. Pharmacy records are useful to establish fill patterns. Objective. Use pharmacy records to establish medication patterns fill patterns for comparison to healthcare utilization. Methods. Pharmacy records of 175 children with persistent asthma were collected and compared to healthcare utilization. Results. Majority of subjects had significant healthcare utilization, low numbers of rescue medications, and poor controller medication fill rates. Those with more rescue medications had more healthcare utilization and more controller medications. Conclusions. Pharmacy fill patterns demonstrate few rescue and/or controller medication fills. Those with more rescue medications reported increased healthcare utilization despite controller medications. 相似文献
6.
A fundamental prerequisite of population health research is the ability to establish an accurate denominator. This in turn requires that every individual in the study population is counted. However, this seemingly simple principle has become a point of conflict between researchers whose aim is to produce evidence of disparities in population health outcomes and governments whose policies promote (intentionally or not) inequalities that are the underlying causes of health disparities. Research into the health of asylum seekers is a case in point. There is a growing body of evidence documenting the adverse affects of recent changes in asylum-seeking legislation, including mandatory detention. However, much of this evidence has been dismissed by some governments as being unsound, biased and unscientific because, it is argued, evidence is derived from small samples or from case studies. Yet, it is the policies of governments that are the key barrier to the conduct of rigorous population health research on asylum seekers. In this paper, the authors discuss the challenges of counting asylum seekers and the limitations of data reported in some industrialized countries. They argue that the lack of accurate statistical data on asylum seekers has been an effective neo-conservative strategy for erasing the health inequalities in this vulnerable population, indeed a strategy that renders invisible this population. They describe some alternative strategies that may be used by researchers to obtain denominator data on hard-to-reach populations such as asylum seekers. 相似文献
7.
目的:了解路桥地区2004年至2006年之间,从业人员健康人群HBsAg、HBsAb的阳性率及大、小三阳所占的比例。方法:对32 490人来体检的健康人群进行乙肝三系二对半检测,采用酶联免疫法(ELISA)测定HBsAg、HBsAb、HBeAg、HBeAb、HBcAb,按不同性别、城区与乡镇之间、两年之间进行比较。结果:不同性别之间HBsAg、HBsAb的阳性率无显著性差异。城区与乡镇之间HBsAg、HBsAb阳性率有显著性差异。两年之间HBsAg的阳性率有下降趋势。大小三阳的比例在各组之间也各不相同。结论:健康人群的乙肝病毒携带率比例偏高,易感者多,相关部门应督促乙肝疫苗的注射,减少乙肝发病率。 相似文献
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Goats infected with Trypanosoma congolense transmitted by Glossina morsitans centralis and then treated with the trypanocidal drug diminazene aceturate are immune to tsetse-transmitted infection with a homologous, but not heterologous trypanosome clone. Immune animals fail to develop localized skin reactions (chancres) and do not become infected, whereas on heterologous challenge chancres appear followed by parasitaemia. In this study, the feasibility of using chancre reactions to characterize several different metacyclic populations of T. congolense was evaluated. Provided goats were immunized, it was found that the chancre reaction could be used to distinguish different populations of T. congolense. However, problems were encountered when attempts were made to induce immunity against more than one trypanosome population. When goats were infected by tsetse flies with four antigenically unrelated metacyclic populations of T. congolense, either simultaneously or at 4 day intervals, adequate immunological priming was not always achieved. In fact, goats exposed to superinfection 8 to 12 days after a primary infection did not develop chancres or an immune response to the second infection (although they were immune to the organism used for primary infection). Following trypanocidal treatment these animals were subsequently completely susceptible to homologous infection with the metacyclic population used for superinfection, indicating that some form of interference phenomenon effective at the level of the skin appears to prevent or delay the development of the second trypanosome population following superinfection of infected animals. 相似文献
9.
A concordance of nucleotide substitutions in the first and second hypervariable segments of the human mtDNA control region 总被引:6,自引:0,他引:6
K. W. P. Miller E. Hagelberg J. L. Dawson 《International journal of legal medicine》1996,109(3):107-113
A new and easily accessible concordance of nucleotide substitutions in the hypervariable segments of the human mitochondrial DNA (mtDNA) control region has been constructed. The concordance indexes all population-specific mtDNA sequences in a standardized format. The first edition of the concordance includes 1,440 sequences representing 762 mtDNA types from over 65 populations for hypervariable region 1, and 520 sequences representing 260 mtDNA types from over 26 populations for hypervariable region 2. Investigators are invited to submit new sequences to the database, and details for doing so are given in the text. 相似文献
10.
Hubert Walter Hideo Matsumoto Heidi Danker-Hopfe Kailash C. Malhotra Biswa N. Mukherjee 《Journal of human genetics》1997,42(1):193-203
Summary Serum samples from eight endogamous Indian tribal populations of Madhya Pradesh (Dhurwa, Halba, Bhatra, Muria, Maria) and
Orissa (Deshia Khond, Binjhal, Kisan) with a total of n=731 unrelated individuals were typed for G1M (1,2,3,17), G3M (5,10,11,13,14,15,16,21,26),
and KM (1). In seven of these populations five different GM haplotypes were found:GM*1,17;21,26; GM*1,17;10,11,13,15,16; GM*1,2,17;21,26; GM*1,3;5,10,11,13,14,26; andGM*3;5,10,11,13,14,26. In the Kisan sample the haplotypeGM*1,2,17; 21,26 is absent. The intergroup variability in the distribution of these haplotypes is considerable and statistically highly significant.
The reasons for that can be attributed to the ethnohistory and to the genetic isolation of these eight endogamous tribal populations.
The GM haplotype distribution pattern of all these groups is quite different from that of the non-tribal populations of India,
whereas it is in good agreement with that of the so far tested other tribal populations from India. This can be explained
by different origin and history of the Indian tribal and non-tribal populations. In the KM system, too, remarkable variability
is seen in the distribution of phenotype and allele frequencies among the eight tribal populations under study. 相似文献