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71.
Stature estimation based on hand length and foot length   总被引:1,自引:0,他引:1  
This study was carried out to estimate the relationship between hand length, foot length and stature using multiple linear regression analyses based on a sample of male and female adult Turks residing in Adana. Measurements of hand length, foot length and stature were taken from 155 adult Turks (80 male, 75 female) aged 17-23 years. The participants were students of the Medical Faculty of Cukurova University. A multiple linear regression model was fitted to the observed data. Stature was taken as the response or dependent variable, hand length and foot length were taken as explanatory variables or regressors. All possible (simple and multiple) linear regression models for each of males, females and both genders together were tested for the best model. The multiple linear regression model for both genders together was found to be the best model with the highest values for the coefficients of determination R2 = 0.861 and R2adjusted = 0.859, and multiple correlation coefficient R = 0.928.  相似文献   
72.
Post-translational modifications of conserved N-terminal tail residues in histones regulate many aspects of chromosome activity. Thr 3 of histone H3 is highly conserved, but the significance of its phosphorylation is unclear, and the identity of the corresponding kinase unknown. Immunostaining with phospho-specific antibodies in mammalian cells reveals mitotic phosphorylation of H3 Thr 3 in prophase and its dephosphorylation during anaphase. Furthermore we find that haspin, a member of a distinctive group of protein kinases present in diverse eukaryotes, phosphorylates H3 at Thr 3 in vitro. Importantly, depletion of haspin by RNA interference reveals that this kinase is required for H3 Thr 3 phosphorylation in mitotic cells. In addition to its chromosomal association, haspin is found at the centrosomes and spindle during mitosis. Haspin RNA interference causes misalignment of metaphase chromosomes, and overexpression delays progression through early mitosis. This work reveals a new kinase involved in composing the histone code and adds haspin to the select group of kinases that integrate regulation of chromosome and spindle function during mitosis and meiosis.  相似文献   
73.
A mismatch amplification mutation assay (MAMA) was developed for identification of point mutations in quinolone resistance-determining region (QRDR) of gyrA at codons 91 and 95. MAMA PCR was used to detect mutations at codons 91 and 95 of gyrA in 117 Neisseria gonorrhoeae isolates (with ciprofloxacin MICs of 0.004 to >32 microg/ml) from Bangladesh during 1997 to 2001. The QRDR regions of the gyrA genes from 31 randomly selected isolates were sequenced, and the results were compared with those of MAMA PCR. Using mismatch PCR, a mutation at Ser91 could be detected in all 27 (resistant and intermediate) isolates, and an Asp95-to-Gly95 mutation could be detected in all 15 isolates, as detected by sequencing. MAMA PCR offers a simple, inexpensive, rapid, and easier alternative for detection of point mutations in fluoroquinolone resistance in N. gonorrhoeae.  相似文献   
74.
Two truncated sequences (designated P1 and rHA1) of influenza A virus subtype H5 haemagglutinin (HA) were cloned and expressed in yeast Pichia pastoris (P. pastoris). These polypeptides were used in an indirect recombinant ELISA (rELISA) for detection of H5 antibodies in poultry. Serum samples obtained from broiler chickens vaccinated with commercial inactivated vaccine (H5N2) and control negative sera from non-vaccinated chickens against influenza were tested using rP1-ELISA, rHA1-ELISA, whole H5N1-ELISA, Western blot, agar gel immunodiffusion (AGID) and haemagglutination inhibition (HI) tests. The rHA1-ELISA proved to be highly sensitive and specific. To study the validity of rHA1-ELISA, a total of 179 serum samples obtained from commercial broiler chickens vaccinated previously with commercial H5N2 inactivated vaccines, were tested by rHA1-ELISA, commercial ELISA (cELISA) and HI. The relative sensitivity and specificity between rHA1-ELISA, and HI tests were 100% and 70%, respectively, and between cELISA and HI were 100% and 57%, respectively. The agreement ratio between rHA1-ELISA and HI was 84.9% and between cELISA and HI tests was 76.5%. Serum samples obtained from ducks vaccinated with commercial inactivated H5N2 were tested by rHA1-ELISA and the results showed significant reactivity with duck sera. In conclusion, the results demonstrate the potential applicability of the rELISA for the determination of antibodies to H5 influenza virus in chickens and ducks.  相似文献   
75.
76.
We present a new marker that confers both resistance to pyrimethamine and green fluorescent protein-based fluorescence on the malarial parasite Plasmodium berghei. A single copy of the cassette integrated into the genome is sufficient to direct fluorescence in parasites throughout the life cycle, in both its mosquito and vertebrate hosts. Erythrocyte stages of the parasite that express the marker can be sorted from control parasites by flow cytometry. Pyrimethamine pressure is not necessary for maintaining the cassette in transformed parasites during their sporogonic cycle in mosquitoes, including when it is borne by a plasmid. This tool should thus prove useful in molecular studies of P. berghei, both for generating parasite variants and monitoring their behavior.  相似文献   
77.

Background

To investigate whether polymorphism rs540782 on chromsome 1, in close proximity to the Zona Pellucida Glycoprotein 4 (ZP4) gene, is a risk factor for primary open angle glaucoma (POAG).

Method

The study genotyped 92 unrelated POAG cases and 95 control subjects from Saudi Arabia using Taq-Man® assay.

Results

The genotype frequency distribution did not deviate significantly from the Hardy-Weinberg equilibrium (p?>?0.05). Overall, both the genotype and allele frequencies were not significantly different between cases and controls. The minor ‘C’ allele frequency was 49.4%, which was comparable to the Japanese population and higher than the Indian and Afro-Caribbean populations. Similarly, no significant association was found between genotypes and systemic diseases and health awareness/behavior domain variables. Importantly, glaucoma specific indices, such as intraocular pressure, cup/disc ratio and number of anti-glaucoma medication, also showed no statistically significant effect of genotypes within POAG cases.

Conclusion

Polymorphism rs540782 is not a risk factor for POAG in the Saudi cohort.
  相似文献   
78.

Background

To investigate the association between polymorphism rs547984, located in close proximity to the Zona Pellucida Glycoprotein 4 (ZP4) gene on human chromosome 1q43 and primary open angle glaucoma (POAG).

Method

Polymorphism rs547984 was genotyped using Taq-Man® assay in 185 subjects comprising of 90 unrelated POAG cases and 95 controls of Saudi origin.

Results

Association analysis between cases and controls revealed no significant genotype distribution under additive (p = 0.356), dominant (p = 0.517) and recessive (p = 0.309) models. Besides, the allele frequency distribution was also found to be non-significant (p = 0.70). The minor “A” allele frequency was found to be 0.49 and 0.50 among POAG cases and controls, respectively. In addition, specific clinical indices used to assess severity of glaucoma such as intraocular pressure (IOP), cup/disc ratio and number of anti-glaucoma medication also did not show any significant genotype distribution in POAG cases.

Conclusion

Polymorphism rs547984 is neither associated with any clinical indices important for POAG such as IOP and cup/disc ratio nor is a risk factor for POAG in the Saudi cohort.
  相似文献   
79.
The majority of in-vitro-derived human preimplantation embryos are chromosomally abnormal but whether the same pattern exists in vivo is unknown. This would be impossible to demonstrate in humans. Hence we chose murine embryos to study this difference owing to their ease of manipulation and compared the incidence of mosaicism between in-vivo- and in-vitro-cultured embryos. Two groups of embryos were analysed. Group A (in vitro) were obtained 48h following superovulation and cultured in vitro until the blastocyst stage. Fluorescent in-situ hybridization (FISH) was performed at different stages that included the cleavage, morula and blastocyst stage. Group B (in vivo) were obtained on day 2 or day 5 and FISH was performed immediately without culture. There was an increase in chromosomal mosaicism seen from the cleavage stage up to the blastocyst stage in the in-vitro culture group. Overall chromosomal abnormality from day 3 to day 5 was found to be 30% (28/94) in group A. The incidence of chromosomal abnormalities in blastocysts from group B was significantly lower than group A blastocysts (8% (3/40) and 31% (20/64) respectively; P<0.05). These data show that in-vitro cultured embryos had a significantly higher incidence of mosaicisim in comparison with the in-vivo group. Cultured human embryos show high levels of chromosomal abnormalities but whether this is a pattern seen in all embryos or is the result of culture is unknown. To study this pattern we used mouse embryos and carried out chromosome analysis by fluorescent in-situ hybridization. We compared embryos that were cultured (in vitro) with those that were not (in vivo, i.e. grown exclusively in the mouse). We found that cultured embryos showed significantly higher chromosomal abnormalities as compared with in vivo embryos. This suggests that certain culture conditions are responsible for the high level of chromosomal abnormalities seen in these embryos, which should be investigated further.  相似文献   
80.

Background

The introduction of tobacco plain packaging legislation in Australia meant that all tobacco products were to be sold in plain dark-brown packaging with 75 % front-of-pack graphic health warnings and standardised font type and size for brand name and product variant. The change in the size and prominence of the warnings has been proposed as a reason for behaviour change in smokers in terms of increased intentions to quit and quit attempts.

Purpose

The current research examined attitudes and beliefs of cigarette smokers toward the increased size and prominence of the warnings and effects on their behaviour.

Method

Participants (N?=?160) completed open-ended responses to questions on beliefs, attitudes and responses to plain packaging. Responses were subjected to inductive thematic content analysis for key themes.

Results

Four themes emerged from the analysis: emotional response to packaging, scepticism of health warnings, warnings and cessation behaviour, and avoidant coping behaviours. Participants reported increased negative emotional responses to the packaging and made specific reference to the graphic health warnings. Some participants attempted to discredit the messages. Others reported increased intentions to quit or quitting attempts. There were pervasive reports of avoidant responses including covering or hiding the warnings.

Conclusion

Consistent with theories of illness perceptions and coping, current findings indicate that the larger, prominent graphic health warnings on plain-packaged tobacco products had pervasive effects on threat perceptions and subsequent behavioural responses. While some of the reported responses were adaptive (e.g. attempts to quit), others were maladaptive (e.g. avoiding the warnings).
  相似文献   
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