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921.
922.
S Ali S Ansari NZ Ehtesham MA Azfer U Homkar R Gopal SE Hasnain 《Canadian Metallurgical Quarterly》1998,223(1-2):361-367
We have analyzed the genome of central Indian swamp deer Cervus duvauceli branderi, an inhabitant of the Kanha National Park, a wildlife conservatory in Central India, with a view to provide a genetic basis for their extinction. Evolutionarily conserved repeat sequence motifs (GATA)3.75, TA(GATA)4, (GACA)3.75, (TGG)6 and a set of mouse beta-actin primers were used to uncover the sequence variation within and between related species by employing techniques of hybridization and AP-PCR amplification. The oligo probe carrying the GACA and TGG repeat motifs was found to be positive with Cervus genome, whereas (GATA)3.75, TA(GATA)4 and beta-actin probes did not cross-hybridize with the same. AP-PCR amplification with (GACA)3.75, unlike the (TGG)6 primer, generated distinct bands in the range of 0. 37-2.10kb amongst different genomes including Cervus. A comparative genome analysis of other species using the AP-PCR approach with (GACA)3.75 primer revealed the phylogenetic status of Cervus duvauceli branderi. From the analysis of a very limited number of Cervus DNA samples, we observed a high level of genetic homogeneity that may be a prime reason for the extinction of this species. This study has implications in the context of conservation of this endangered Cervus duvauceli branderi species. 相似文献
923.
R Hovorka P Bannister DJ Eckland D Halliday DN Murley SE Rees MA Young 《Canadian Metallurgical Quarterly》1998,15(3):234-246
We have investigated the reproducibility of (1) insulin sensitivity (S*I) and glucose effectiveness (S*G) as measured by the stable-label (one compartment) minimal model, and (2) insulin sensitivity (S*Ib), plasma clearance rate (PCR), basal hepatic output (HGOb), and total hepatic glucose output (HGO0-240) as measured by the novel stable-label two compartment model of glucose disappearance during labelled intravenous glucose tolerance test (IVGTT) using 6,6-(2)H-glucose. Ten normal male subjects were studied on two occasions one week apart. Both models provided estimates of all indices with acceptable precision (CV of parameter estimates < or =50%). The within subject CVs of S*I and S*Ib were comparable (17% vs 19%) as were the within subject CVs of S*G and PCR (13% vs 16%). A highly significant linear relationship was observed between S*Ib and S*I (0.303 +/- 0.046 ml kg(-1) min(-1) per mU l(-1) vs 13.04 +/- 1.89 10(-4) min(-1) per mU l(-1), y = 0.0037 x + 0.0002, r = 0.90, p < 0.001; mean +/- SE), but not between PCR and S*G (1.98 +/- 0.15 ml kg(-1) min(-1) vs 0.0089 +/- 0.0005 min(-1), rs = 0.34, NS). The two compartment model provided a plausible time-profile of hepatic glucose output during IVGTT, reproducible estimates of HGOb (1.96 +/- 0.18 mg kg(-1) min(-1), 15%; mean +/- SE, within subject CV), and a highly reproducible HGO0-240 (7%; within subject CV). We conclude that the stable-label (one compartment) minimal model and the stable-label two compartment model provide reproducible estimates of parameters of glucose kinetics in normal subjects. Insulin sensitivity indices estimated by the two models are strongly linearly related. 相似文献
924.
SE Ostroy 《Canadian Metallurgical Quarterly》1998,17(10):979-985
BACKGROUND: We sought to describe changes in spirometric variables and lung volume subdivisions in healthy subjects and patients with chronic obstructive pulmonary disease (COPD) during moderate acute hypobaric hypoxia as occurs during air travel. We further questioned whether changes in lung function may associate with reduced maximum ventilation or worsened arterial blood gases. METHODS: Ambulatory patients with COPD and healthy adults comprised the study populations (n = 27). We obtained baseline measurements of spirometry, lung volumes and arterial blood gases from each subject at sea level and repeated measurements during altitude exposure to 8000 ft (2438 m) above sea level in a man-rated hypobaric chamber. RESULTS: Six COPD patients and three healthy subjects had declines in FVC during altitude exposure greater than the 95% confidence interval (CI) for expected within day variability (p < 0.05). Average forced vital capacity (FVC) declined by 0.123 +/- 0.254 L (mean +/- SD; 95% CI = -0.255, -0.020; p < 0.05) for all subjects combined. The magnitude of decline in FVC did not differ between groups (p > 0.05) and correlated with increasing residual volume (r = -0.455; <0.05). Change in maximum voluntary ventilation (MVV) in the COPD patients equaled -1.244 +/- 4.797 L x min(-1) (95% CI = -3.71, 1.22; p = 0.301). Decline in maximum voluntary ventilation (MVV) in the COPD patients correlated with decreased FVC (r = 0.630) and increased RV (r = -0.546; p < 0.05). Changes in spirometric variables for patients and controls did not explain significant variability in the arterial blood gas variables PaO2, PaCO2 or pH at altitude. CONCLUSIONS: We observed a decline in forced vital capacity in some COPD patients and normal subjects greater than expected for within day variability. Spirometric changes correlated with changes in reduced maximum voluntary ventilation in the patients but not with changes in resting arterial blood gases. 相似文献
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926.
927.
Principles are presented for improving the spatial accuracy of manufacturing machines by combining novel spatial gauging equipment, versatile desktop computers, powerful software, and sound statistical techniques. A novel multiple regression procedure is presented to evaluate parameters for dimensional correction that reduce the machine's residual errors to their minimum-least-squares value. The technique is particularly applicable to computer-controlled machines 相似文献
928.
SE Oberfield D Soranno A Nirenberg G Heller JC Allen R David LS Levine CA Sklar 《Canadian Metallurgical Quarterly》1996,150(6):589-592
OBJECTIVE: To determine if a relationship exists between age at irradiation, sex of the patient, and age at onset of puberty and pubarche in children treated with high-dose radiation to the central nervous system. DESIGN: Case series. SETTING: Tertiary care institutional practices and clinics. PATIENTS: Thirty-six children treated with high-dose irradiation (hypothalamic pituitary dose, 30-72 Gy) by conventional (n = 29) or hyperfractionated (n = 7) schedules. Girls were treated before age 8 years and boys before age 9 years. Twenty-six of the 36 children also received chemotherapy. All tumors were distant from the hypothalamic-pituitary region. MAIN OUTCOME MEASURE: Age at onset of puberty and pubarche. RESULTS: In girls, the median age at onset of puberty was 9.3 years vs 10.9 years for controls (P < .01); pubarche occurred at 9.4 years vs 11.2 years for controls (P < .01). In boys, the median age at onset of puberty--genital II--was 11.0 years vs 11.5 years for controls (P = .30); pubarche occurred at a median age of 10.5 years vs 12 years for controls (P = .25). A censored-data normal linear regression model was used to account for children (n = 6) who had not reached puberty. Age at diagnosis (P < .01) and sex (P = .01) were significant predictors of age at onset of puberty. Body mass index SD score (z score) was inversely related to age at onset of puberty (r = -0.77) and was greater at onset of puberty in girls than in boys. CONCLUSION: In children who have received high-dose cranial radiation therapy, a significant positive correlation exists between age at diagnosis and age at onset of puberty in boys and girls. 相似文献
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930.