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1.
Three phenotypes of phosphoglucose isomerase (PGI) were detected in abdominal muscle extracts from the shrimp (Metapenaeus affinis) by starch-gel electrophoresis. The observed phenotypes were assumed to be under the control of two allelic genes. This assumption was supported by the observed distribution of phenotypes. There were no significant differences in the distribution of PGI phenotypes among samples of shrimp taken from Basrah waters, Iraq and from Kuwaiti waters, Arab Gulf. The three PGI alleles observed in M. affinis appear to be the same in the two localities.  相似文献   

2.
Anomaloscopic diagnoses of red-green vision defects are reported and compared to the Ishihara tests for six Israeli populations. The highest frequencies of defects, about 10%, were found in an Arab sample and among Ashkenazi Jews; the lowest — about 4% — among Yemenite Jews. Heterogeneity was also found regarding the relative frequencies of the different alleles; these differences are due primarily to alleles causing milder defects (particularly deuteranomaly) while frequencies of anopias are rather similar. It seems that the same phenomenon prevails for other population differences as well. These findings are discussed in relation to the hypothesis that present-day high rates of colorblindness in some populations may be explained by the relaxation of selection pressure against colorblindness.  相似文献   

3.
Apolipoproteins (lipid-free) are lipid-binding proteins that circulate in the plasma of human blood and are responsible for the clearance of lipoproteins. Apolipoprotein E (ApoE) is one of the several classes of this protein family. It acts as a ligand for the low-density lipid (LDL) receptors and is important for the clearance of very low-density lipid (VLDL) and chylomicron remnants. The APOE gene locus is polymorphic, with three major known alleles, APOE*3, *4, and *2. We investigated the distribution of the allele frequency of the APOE gene locus and describe here the genetic variation in four Kuwaiti subpopulations: Arab origin (Arabian peninsula), Arab Bedouin tribes, Iranian origin, and the heterogeneous population. We also describe the use of Spreadex gels in resolving the amplified and digested products of the APOE gene locus. DNA was extracted from whole blood and subjected to PCR and then to RFLP analysis. Allele and genotype frequencies were estimated for the total population and for each subpopulation. Statistical analysis showed no difference in the allele frequencies between the four groups. The frequency of APOE*3 in the Kuwaiti population was highest (88.4%) followed by the frequency of APOE*4 (6.5%) and APOE*2 (5.1%). The genotype and allele frequencies obtained for the Kuwaiti population fell within the reported worldwide distribution for the APOE gene locus. Moreover, the results obtained in this study showed no statistical difference (p > 0.05) between the APOE allele and genotype frequencies between the subgroups for all six genotypes and three alleles, supporting the assumption of admixture in the Kuwaiti population and that the obtained frequencies were in Hardy-Weinberg equilibrium. Finally, we found that the distribution of the APOE alleles in Kuwait differs somewhat from those reported in other Arab populations, suggesting that the Arabs originating from the Arabian peninsula are different from those of Lebanon, Morocco, and Sudan.  相似文献   

4.
Summary Idiopathic generalized epilepsies (IGEs) are the most common types of epilepsy in childhood and adolescence. A variety of data suggest that IGEs have a predominant genetic etiology. Recently, a number of gene mutations have been found to be associated with various types of epilepsy in mainly the Caucasian populations. The objective of this study was to investigate the association of three different candidate genes with IGE in Kuwaiti Arab children. This study includes 123 Kuwaiti patients with a confirmed diagnosis of epilepsy. Most of the patients have had a diagnostic EEG with generalized spike-wave discharges (GSWs). All patients were evaluated by using a validated seizure questionnaire. The clinical type of epilepsy was determined by a trained neurologist/pediatrician. The study also include 100 controls, the control subjects were children which did not have any history of neurological disorders. Blood samples were collected from all patients and control subjects after taking informed consent. DNA was isolated and analyzed by molecular methods. A FokI polymorphism in neuronal nicotinic acetylcholine receptor alpha-4 subunit (CHRNA4) gene was detected by PCR-RFLP method. A missense mutation (Ser248Phe) in CHRNA4 gene was analyzed by PCR-RFLP using HpaII. A C121W mutation in sodium-channel beta-1 subunit (SCN1B) gene was screened by a PCR-RFLP method using HinPI. A 2-bp deletion in Cystatin B gene was detected by PCR-RFLP using XcmI. The incidence of three FokI polymorphism genotypes in Kuwaiti IGE patients was 1,1 (85%), 1,2 (14%) and 2,2 (1%) respectively. The missense mutation Ser248Phe of CHRNA4 gene was not detected at all in Kuwaiti IGE patients. The C387G transversion resulting in C121W change in third exon of the SCN1B gene was detected in 3/123 patients (2%). The patients carrying this mutation also exhibited febrile seizures. The incidence of 2 bp deletion in the cystatin B gene was found to be 4% (5/123 IGE patients). The data obtained from molecular analysis show a lack of association between three candidate genes and clinical expression of IGE in Kuwaiti Arab children. This is completely different from the findings reported from Caucasian populations of France, Australia and USA in which case a strong association has been reported between IGE and these genes. To whom corresspondence should be addressed. Tel: +965-5319486; Fax: +965-5338940; E-mail: haider@hsc.edu.kw  相似文献   

5.
The study analyzed new information regarding the way in which present day Russians (living in Moscow or Tula) perceive societal risks. The main concerns of Russians in year 2003 were essentially the same ones that were identified in previous studies conducted on Western samples: violence, sex, and addiction-type hazards received the highest risk ratings. Women's mean risk judgments were systematically higher than men's mean judgments, and older participants' mean judgments were higher than younger participants' mean judgments regarding domestic hazards. Technically trained people perceived higher societal risk than people with training in the humanities, but the difference between people with technical training and people trained in the humanities was more accentuated among younger people than among the elderly. Also, men living in Tula perceived themselves as less exposed to risks of violence than women living in Tula and both men and women living in Moscow.  相似文献   

6.
Data used in this study come from the published reports of the censuses and vital registration systems. The crude birth rate in Kuwait is very high, although an apparent decline seems to have started in the period 1975-80. There are considerable differences between the Kuwaiti and non-Kuwaiti populations. The former had a relatively stable high rate around 50 until 1975 and then fell to 47 in 1980. The total fertility rate was 6.8 per woman. The rate for the non-Kuwaitis rose in 1965-70 and then fell sharply throughout 1970-1980, from 44 to 30. Non-Kuwaiti fertility is consistently lower than Kuwaiti fertility at all ages, the differences being relatively greater after age 35. The peak ages of fertility are 25-29 years for Kuwaitis and 20-29 years for non-Kuwaitis. For Kuwaitis, there is clear evidence of declining fertility in the younger age groups but not in the older, largely reflecting the trend towards later marriage among the younger Kuwaitis. As expected, there is a diminishing trend in completed family size from the least to the most educated women in both Kuwaiti and non-Kuwaiti women in all age groups. The illiterate women at marriage are younger than the university educated women by about 5 years. Results further show that women who are economically active have lower fertility than those who are not, both in Kuwaiti and non-Kuwaiti groups. The differences in each group are significant, as are differences in the fertility level by husband's occupation. High fertility in Kuwait, as well as in other oil-exporting Arab countries, is a result of a variety of factors including the generally pronatalist sentiment of the Arab population, improved health facilities, rising wealth, the youthful age structure, the young age at marriage and the substantial incentives in the different governmental schemes to promote native high fertility and keep a balance between the native and immigrant populations.  相似文献   

7.
8.
The thermosensory system was evaluated psychophysically in 12 healthy volunteers, spanning the full range of tolerable temperatures. Subjects provided ratings of (1) perceived thermal intensity, (2) perceived pleasantness or unpleasantness, and (3) perceived pain intensity after placing either one hand or foot in a temperature controlled water bath. Of particular interest were the interrelationships among the three perceptual measures, and differences between heat and cold. The relationship between perceived intensity and (un)pleasantness was different for hot vs cold stimuli. Specifically, for a given perceived thermal intensity, cold stimuli were rated as less pleasant or more unpleasant than hot stimuli. Similarly, for a given pain intensity, cold stimuli were rated as more unpleasant than hot stimuli. As warm temperatures increased and as cold temperatures decreased, stimuli were perceived as being unpleasant before they were perceived as being painful. The difference in transition temperatures for unpleasantness vs pain for heat averaged 1.4 degrees C, while the same difference for cold averaged 5.6 degrees C. Thus, there was a fourfold difference in the range of unpleasant but non-painful cold vs hot temperatures. Pain intensity and unpleasantness ratings were significantly higher for heat stimuli applied to the foot vs hand. In contrast, there was no significant body site difference for pain intensity or unpleasantness ratings of cold stimuli. All of these results reveal important differences in the processing of cold vs hot stimuli. These differences could be exploited to differentiate processing relevant to discriminative vs affective components of somesthetic perception, in both the innocuous and noxious ranges.  相似文献   

9.
Lim J  Urban L  Green BG 《Chemical senses》2008,33(6):493-501
Previous reports that the sensitivity to the bitter tasting substance 6-n-propylthiouracil (PROP) is related to the sensitivity to other tastes, to chemical irritants, and to fats and oils have led to adoption of PROP as a measure of general oral sensitivity and as a predictor of dietary habits that could impact health. The results, however, have not been consistent. It was recently discovered that the ability to perceive "thermal taste" (i.e., sweetness from thermal stimulation alone) was associated with higher responsiveness to 4 prototypical taste stimuli but not to PROP. This finding implied that individual differences in taste perception are determined in large part by factors other than those related to genetic expression of the PROP receptor. The present study followed up this observation by comparing individual differences in perception of 4 prototypical taste stimuli (sucrose, NaCl, citric acid, and quinine) and PROP under conditions that also enabled assessment of the reliability of individual intensity ratings of taste. Creaminess ratings of 3 milk products that had different fat contents were also collected to investigate further the relationship between taste and oral somatosensory perception. The results showed that intensity ratings across 2 trials were significantly correlated for all 5 taste stimuli and that averaging across replicates led to significant correlations among the 4 prototypical stimuli. In contrast, the bitterness of PROP was correlated only with the bitterness of quinine. None of the taste stimuli, including PROP, was significantly correlated with ratings of creaminess. These results imply 1) that with the exception of PROP, as few as 2 intensity ratings of common taste stimuli can reveal individual differences in overall taste perception and 2) that any relationship between taste and oral sensation is too weak to be detected under the same conditions. Accordingly, the results support other evidence that the genetic factors which determine the ability to perceive PROP do not play a major role in overall taste and oral somatosensory perception.  相似文献   

10.
11.
The association between both HLA-A1 and B5 antigens and chronic forms of human schistosomiasis was studied in 64 patients and 26 normal controls from a southern Brazilian hospital. No apparent correlation between the chronic forms of the disease and the expression of those antigens was detected. However, the analysis of these data together with those observed on an Egyptian sample suggests that the presence of either of the antigens and the hepatomegalic forms of schistosomiasis is significant, without heterogeneity. Conversely, the association of histocompatibility antigens with splenomegaly is consistent and significant only for HLA-B5, but not HLA-A1.  相似文献   

12.
The integrin alpha(v)beta3, whose alpha(v) subunit is encoded by the ITGAV gene, plays a key role in angiogenesis. Hyperangiogenesis is involved in rheumatoid arthritis (RA) and the ITGAV gene is located in 2q31, one of the suggested RA susceptibility loci. Our aim was to test the ITGAV gene for association and linkage to RA in a family-based study from the European Caucasian population. Two single nucleotide polymorphisms were genotyped by PCR-restriction fragment length polymorphism in 100 French Caucasian RA trio families (one RA patient and both parents), 100 other French families and 265 European families available for replication. The genetic analyses for association and linkage were performed using the comparison of allelic frequencies (affected family-based controls), the transmission disequilibrium test, and the genotype relative risk.We observed a significant RA association for the C allele of rs3738919 in the first sample (affected family-based controls, RA index cases 66.5% versus controls 56.7%; P = 0.04). The second sample showed the same trend, and the third sample again showed a significant RA association. When all sets were combined, the association was confirmed (affected family-based controls, RA index cases 64.6% versus controls 58.1%; P = 0.005). The rs3738919-C allele was also linked to RA (transmission disequilibrium test, 56.5% versus 50% of transmission; P = 0.009) and the C-allele-containing genotype was more frequent in RA index cases than in controls (RA index cases 372 versus controls 339; P = 0.002, odds ratio = 1.94, 95% confidence interval = 1.3-2.9). The rs3738919-C allele of the ITGAV gene is associated with RA in the European Caucasian population, suggesting ITGAV as a new minor RA susceptibility gene.  相似文献   

13.
The perception of vowels was studied in chimpanzees and humans, using a reaction time task in which reaction times for discrimination of vowels were taken as an index of similarity between vowels. Vowels used were five synthetic and natural Japanese vowels and eight natural French vowels. The chimpanzees required long reaction times for discrimination of synthetic [i] from [u] and [e] from [o], that is, they need long latencies for discrimination between vowels based on differences in frequency of the second formant. A similar tendency was observed for discrimination of natural [i] from [u]. The human subject required long reaction times for discrimination between vowels along the first formant axis. These differences can be explained by differences in auditory sensitivity between the two species and the motor theory of speech perception. A vowel, which is pronounced by different speakers, has different acoustic properties. However, humans can perceive these speech sounds as the same vowel. The phenomenon of perceptual constancy in speech perception was studied in chimpanzees using natural vowels and a synthetic [o]- [a] continuum. The chimpanzees ignored the difference in the sex of the speakers and showed a capacity for vocal tract normalization.  相似文献   

14.
This study cross-nationally tested an eight-factor model of societal risk perception. The factors in the model were: Common individual hazards, Pollutants, Energy production and public transportation, Outdoor activities, Sex, deviance and addictions, Medical care, Weapons, and Psychotropic drugs. Using confirmatory factor analyses, the model was tested on a sample of Greek students and on a sample of French students, and was shown to satisfactorily account for the data in both samples. This model may be considered as a potentially useful tool for studying cross-national as well as individual differences (e.g., age, gender, worldviews or personality) in risk perception. Future studies are needed to determine: (a) whether this model applies to samples composed of persons of different ages or composed of persons from non-Western countries and (b) whether this model could be usefully expanded with one or more factors.  相似文献   

15.
Approximately 300 subjects participated in a test to determine whether the level of salt in popcorn affected the change in overall liking observed as a consequence of consuming a serving of popcorn. Subjects tasted and rated three samples of popcorn (low, medium, high salt levels), ate a serving of popcorn at one of the salt levels and then tasted and rated the three samples again. Subjects returned one or seven days later and tasted and rated the samples again. Overall liking, salt intensity and salt liking were measured. The subjects also completed a questionnaire about their liking and consumption of popcorn. Liking scores for the popcorns decreased after eating a 3-cup serving; however, sensory specific satiety for the different levels of salt was not observed. Consuming low salt popcorn increased the rated saltiness of the popcorns, whereas consuming high salt popcorn decreased the rated saltiness — probably a frequency effect. When subjects retasted the popcorns one or seven days later, all liking ratings increased except the salt liking ratings for the high salt sample. There was also a trend for the overall liking of this high salt sample to increase less than for the medium and low salt samples. Questionnaire measures of liking or consumption were not related to the changes in liking observed.  相似文献   

16.
One central issue in social cognitive neuroscience is that perceiving emotions in others relates to activating the same emotion in oneself. In this study we sought to examine how the ability to perceive own emotions assessed with the Toronto Alexithymia Scale related to both the ability to perceive emotions depicted in point-light displays and the confidence in these perceptions. Participants observed video scenes of human interactions, rated the depicted valence, and judged their confidence in this rating. Results showed that people with higher alexithymia scores were significantly less confident about their decisions, but did not differ from people with lower alexithymia scores in the valence of their ratings. Furthermore, no modulating effect of social context on the effect of higher alexithymia scores was found. It is concluded that the used stimuli are fit to investigate the kinematic aspect of emotion perception and possibly separate people with high and low alexithymia scores via confidence differences. However, a general difference in emotion perception was not detected in the present setting.  相似文献   

17.
Objective To examine differences in expectations for health using anchoring vignettes, which describe fixed levels of health on dimensions such as mobility.Design Cross sectional survey of adults living in the community.Setting China, Myanmar, Sri Lanka, Pakistan, Turkey, and United Arab Emirates.Participants 3012 men and women aged 18 years and older (self ratings); subsample of 406 (vignette ratings).Main outcome measures Self rated mobility levels and ratings of hypothetical vignettes using the same questions and response categories.Results Consistent rankings of vignettes are evidence that vignettes are understood in similar ways in different settings, and internal consistency of orderings on two mobility questions indicates good comprehension. Variation in vignette ratings across age groups suggests that expectations for mobility decline with age. Comparison of responses to two different mobility questions supports the assumption that individual ratings of hypothetical vignettes relate to expectations for health in similar ways as self assessments.Conclusions Anchoring vignettes could provide a powerful tool for understanding and adjusting for the influence of different health expectations on self ratings of health. Incorporating anchoring vignettes in surveys can improve the comparability of self reported measures.  相似文献   

18.
19.
An experiment was set up for (i) comparing Australian and French consumer preferences to beef and to (ii) quantify how well the Meat Standards Australia (MSA) grading model could predict the eating quality of beef in France. Six muscles from 18 Australian and 18 French cattle were tested as paired samples. In France, steaks were grilled ‘medium’ or ‘rare’, whereas in Australia ‘medium’ cooking was used. In total, 360 French consumers took part in the ‘medium’ cooking test, with each eating half Australian beef and half French beef and 180 French consumers tested the ‘rare’ beef. Consumers scored steaks for tenderness (tn), juiciness (ju), flavour liking (fl) and overall liking (ov). They also assigned a quality rating to each sample: ‘unsatisfactory’, ‘satisfactory everyday quality’ (3*), ‘better than everyday quality’ (4*) or ‘premium quality’ (5*). The prediction of the final ratings (3*, 4*, 5*) by the French consumers using the MSA-weighted eating quality score (0.3 tn + 0.1 ju + 0.3 fl + 0.3 ov) was over 70%, which is at least similar to the Australian experience. The boundaries between ‘unsatisfactory’, 3*, 4* and 5* were found to be ca. 38, 61 and 80, respectively. The differences between extreme classes are therefore slightly more important in France than in Australia. On average, even though it does not have predictive equations for bull meat, the mean predicted scores calculated by the MSA model deviated from observed values by a maximum of 5 points on a 0 to 100 scale except for the Australian oyster blade and the French topside, rump and outside (deviating by <15). Overall, the data indicate that it would be possible to manage a grading system in France as there is high agreement and consistency across consumers. The ‘rare’ and ‘medium’ results are also very similar, indicating that a common set of weightings and cut-offs can be employed.  相似文献   

20.
A polymorphic AC repeat in intron 1 of the EGFR gene was genotyped on 352 healthy individuals and 118 women with breast cancer sampled from the Kuwaiti and Tunisian populations. We compared allele frequencies in these populations with published data on various ethnic groups. We found very close similarity between Tunisian and Kuwaiti populations for both allelic and genotypic frequencies and in both control and patient groups. Our analysis revealed clear interethnic differences between populations; in Europeans, allele 16 occurred predominantly, whereas in Tunisia and Kuwait allele 17 was the most frequent and allele 20 predominated in Asians. One hundred twenty-three healthy women, matched with the 118 breast cancer patients, were used as controls to test for associations between AC repeat and cancer risk. Strong evidence for such an association was found for allele 18 when considered alone (chi2=27.04, corrected p=0.0000016, OR=3.94) or with longer alleles (>17 repeats) (chi2=20.21, p=0.0005, OR=2.30). This contrasts with Asian populations where allele 16 was identified as the risk allele, showing allele heterogeneity depending on ethnicity.  相似文献   

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