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911.
PURPOSE: The purpose of this paper is to determine the age-specific relationships between risk factors at age 40 through 75 years and ischemic heart disease (IHD), and to determine the effects of aging on these relationships in a cohort of 3983 Canadian males. METHODS: The Manitoba Follow-Up Study is the prospective investigation of cardiovascular disease as it develops in a cohort of 3983 young men. Over a period of 45 years, from 1948 to 1993, 1094 study members (27%) developed clinical evidence of IHD. Blood pressure, body weight, smoking, and presence of diabetes mellitus have been recorded at regular intervals throughout the follow-up period. Using measurements from examinations every 5 years between ages 40 and 75 years, age-specific Cox proportional hazard models were fit to relate these risk factors to IHD. RESULTS: The adjusted relative risk of IHD for systolic blood pressure, diastolic blood pressure and smoking were found to significantly (p < 0.001) decline with advancing age. The adjusted relative risk for body mass index and presence of diabetes mellitus for ischemic heart disease did not vary with age (p > 0.05). After age 65 years, these risk factors were of little value for the prediction of IHD. CONCLUSIONS: The relative risk and statistical significance of blood pressure and smoking, as risk factors for IHD, decline with age. 相似文献
912.
The practice of recruitment and selection of student nurses at a college of nursing in Kwazulu/Natal
This is a report on a study that was conducted to obtain the nurse-educators and student nurses' views regarding recruitment and selection techniques used at a particular college of nursing to attract school leavers for nurse training. A survey was conducted on a sample of forty student nurses at their third and fourth year level of training as well as twenty nurse-educators. Analysis of findings revealed that a substantial number of nurse-educators were not well versed with the selection policy followed at the college. Furthermore, it showed that recruitment was not done and that the selection criteria used were not relevant to the nature and scope of the curriculum of the four year comprehensive diploma course. 相似文献
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915.
RH Mach ST Elder TE Morton PA Nowak PH Evora JG Scripko RR Luedtke CD Unsworth T Filtz AV Rao 《Canadian Metallurgical Quarterly》1993,20(6):777-794
[18F]4-Fluorobenzyl iodide ([18F]FBI) was prepared, and a series of model alkylation studies were conducted to determine its chemical reactivity toward nitrogen and sulfur nucleophiles of varying nucleophilicities. [18F]FBI was found to react rapidly with secondary amines and anilines to give the corresponding N-[18F]4-fluorobenzyl analogue in high yield. Amides and thiol groups required the use of a base catalyst. The utility of [18F]FBI was documented by investigation of dopamine D1 and D2 receptor-based radiotracers. 相似文献
916.
D Gnatenko TE Arnold S Zolotukhin GJ Nuovo N Muzyczka WF Bahou 《Canadian Metallurgical Quarterly》1997,45(2):87-98
Investigations into the incidence of Salmonella abortus ovis (S. abortus ovis) infections should not be neglected in diagnosis of ovine abortion cases. For detection of this pathogen agent, direct cultivation, as well as pre-enrichment combined with enrichment procedures in tetrathionate or Rappaport-Vassiliadis medium, should be performed with respect to the features of S. abortus ovis. The detection limit of S. abortus ovis using pre-enrichment and enrichment media could be determined using 6.5 x 10(3)-6.5 x 10(4) bacteria. For subsequent cultivation of S. abortus ovis Gassner, XLD or Rambach agar are suitable. In infected sheep showing no excretion of S. abortus ovis, the pathogen can be detected by serological studies using microagglutination or the ELISA test. The ELISA test proved to be more sensitive than the microagglutination test, detecting antibodies against S. abortus ovis in 17% of the 814 sheep tested. The microagglutination test revealed positive results in only 2% of the sheep tested. 相似文献
917.
A system is presented for experimental arterial input function (AIF) simulation and for accurate measurement of the concentration, susceptibility effects, and magnetic moment of paramagnetic MR contrast agents. Signal effects of contrast agents are evaluated with a stable, well-characterized, and precise experimental setup. A cylindrical phantom and a closed-loop circulating flow system were designed for AIF simulation, assessment of the physical determinants of contrast-agent phase effects, and measurement of contrast-agent properties under controlled conditions. A mathematical model of the AIF dynamics is proposed. From the experimental phase shift (delta phi), either the concentration or molar susceptibility, chiM, is determined. The linear dependence of delta phi on concentration and echo time (TE), the orientation dependence, and the lack of dependence on T1, T2, and diffusion time are proven precisely for water solutions under a wide variety of conditions. The measured effective magnetic moment of Gd+3, mu(eff), was 7.924 +/- 0.015 Bohr magnetons in agreement with the theoretical value of 7.937. 相似文献
918.
Steroid receptor coactivator-1 is a histone acetyltransferase 总被引:2,自引:0,他引:2
TE Spencer G Jenster MM Burcin CD Allis J Zhou CA Mizzen NJ McKenna SA Onate SY Tsai MJ Tsai BW O'Malley 《Canadian Metallurgical Quarterly》1997,389(6647):194-198
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920.
Using a novel in vitro assay which allows us to distinguish vesicle budding from subsequent targeting and fusion steps, we provide the first biological evidence that beta-COP, a component of non-clathrin-coated vesicles believed to mediate intraGolgi transport, is essential for transport of protein from the ER to the cis-Golgi compartment. Incubation in the presence of beta-COP specific antibodies and F(ab) fragments prevents the exit of vesicular stomatitis virus glycoprotein (VSV-G) from the ER. These results demonstrate that beta-COP is required for the assembly of coat complexes mediating vesicle budding. Fractionation of rat liver cytosol revealed that a major biologically active form of beta-COP was found in a high molecular pool (> 1,000 kD) distinct from coatomer and which promoted efficient vesicle budding from the ER. Surprisingly, rab1B could be quantitatively coprecipitated with this beta-COP containing complex and was also essential for function. We suggest that beta-COP functions in an early step during vesicle formation and that rab1B may be recruited as a component of a precoat complex which participates in the export of protein from the ER via vesicular carriers. 相似文献