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21.
Nutrition early in life may influence adult mortality. The fetal-origins hypothesis suggests that nourishment before birth and during the individual's infancy programs the development of risk factors for several important diseases of middle and old age. The present study was designed to evaluate the impact of extreme nutritional deprivation in utero and during infancy and early childhood on mortality in later life. The authors analyzed the survival of the cohorts born in Finland during the severe 1866-1868 famine and during the 5 years immediately preceding and 5 years immediately following the famine. The study included 331,932 individuals born prior to the famine, 161,744 born during the famine, and 323,321 born after the famine. The authors assessed survival by cohorts from birth to age 17 years and from age 17 to 40, 60, and 80 years, as well as average length of life after age 80 years. Survival from birth to age 17 years was significantly lower in cohorts born before and during the famine than in the cohorts born after the famine (males, 0.566 vs. 0.671, a difference of 0.105 (95% confidence interval (CI) 0.102-0.108); females, 0.593 vs. 0.692, a difference of 0.099 (95% CI 0.096-0.102)). At subsequent ages, including old age, mortality was practically identical in the famine-born cohorts and in the five cohorts born before and after the crisis. For both males and females, survival from 17 to 80 years and mean remaining lifetime at age 80 years were very similar across the 13 cohorts studied. These findings suggest that, although cohorts subjected to prolonged and extreme nutritional deprivation in utero and during infancy and early childhood suffer an immediate rise in mortality, after the crisis has passed, they carry no aftereffects that influence their survival in later life. 相似文献
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This paper presents the results of a longitudinal psychosocial study of 22 cranial trauma patients and 14 stroke patients from the time preceding injury (using retrospective data), through a 4-5 month intensive rehabilitation programme, to a follow-up 1 year after completion of the programme. Although the two groups of patients differed on several demographic and medical characteristics, essentially similar patterns for psychosocial decline following injury and improvement following rehabilitation could be observed. For both groups, the proportion in marital or cohabitational relationships returned to pre-injury levels, and for both groups the proportion requiring assistance in their living situation declined following rehabilitation, as did use of the health services. Virtually all patients in both groups had been in employment or undergoing education at the time of the injury, and although this percentage declined in practice to a small minority of both groups post-injury, there was a significant increase in the proportions working or in education following the rehabilitation programme. Similarly, the pattern of leisure-time activities in both groups declined post-injury and was restored following rehabilitation. Since both groups entered the programme at over 2.5 years post-injury, these generally encouraging results seem less likely to reflect spontaneous recovery than a beneficial effect of the programme itself. 相似文献
24.
NE Taylor RN Rosenthal B Chabus S Levine AS Hoffman J Reynolds L Santos I Willets P Friedman 《Canadian Metallurgical Quarterly》1993,15(1):36-40
Cryptococcal meningitis has a high mortality rate of central nervous infection. The patients usually die of the disease itself, or complications from increased intracranial pressure. Early diagnosis and treatment, including surgical drainage, will improve the results. In this series, twenty-one patients with high intracranial pressure (ICP > 300 mmH2 O) are presented. Fourteen received implantation of Ommaya reservoir to aspirate cerebrospinal fluid (CSF) for relief of symptoms of ICP. Meanwhile 4 of these 14 patients also received intraventricular injection of amphotericin B because of poor response to systemic drugs. Another seven patient received systemic drug therapy only. Survival during therapy occurred in 11 of 14 patients in the surgical group, compared with only 1 of 7 patients treated by drug therapy alone (P = 0.019). In the 14 patients who received implantation of an Ommaya reservoir, there was one complication of CSF leakage when the reservoir ruptured because of repeated aspiration. For patients with cryptococcal meningitis with high ICP, early implantation of an Ommaya reservoir will improve the survival rate. 相似文献
25.
Enhancing heat transfer ability of drag reducing surfactant solutions with static mixers and honeycombs 总被引:4,自引:0,他引:4
Yunying Qi Yasuo Kawaguchi Richard N. Christensen Jacques L. Zakin 《International Journal of Heat and Mass Transfer》2003,46(26):5161-5173
Solutions containing drag reducing additives also show reduced heat transfer which limits their use in district heating and cooling recirculation systems where heat exchange is critical. In this study, static mixers A and B and honeycombs were installed at the entrance to a heat exchanger to break the solution microstructure temporarily and thereby enhancing their heat transfer ability when passing through the heat exchanger. The effectiveness of the destructive devices in enhancing the heat transfer ability of drag reducing cationic and mixed zwitterionic/anionic surfactant solutions was investigated together with the microstructure recovery time and pressure drop penalty paid for the heat transfer enhancement. 相似文献
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Jonathan D. Bray Rodolfo B. Sancio Turan Durgunoglu Akin Onalp T. Leslie Youd Jonathan P. Stewart Raymond B. Seed Onder K. Cetin Ertan Bol M. B. Baturay C. Christensen T. Karadayilar 《Canadian Metallurgical Quarterly》2004,130(7):673-685
Ground failure in Adapazari, Turkey during the 1999 Kocaeli earthquake was severe. Hundreds of structures settled, slid, tilted, and collapsed due in part to liquefaction and ground softening. Ground failure was more severe adjacent to and under buildings. The soils that led to severe building damage were generally low plasticity silts. In this paper, the results of a comprehensive investigation of the soils of Adapazari, which included cone penetration test (CPT) profiles followed by borings with standard penetration tests (SPTs) and soil index tests, are presented. The effects of subsurface conditions on the occurrence of ground failure and its resulting effect on building performance are explored through representative case histories. CPT- and SPT-based liquefaction triggering procedures adequately identified soils that liquefied if the clay-size criterion of the Chinese criteria was disregarded. The CPT was able to identify thin seams of loose liquefiable silt, and the SPT (with retrieved samples) allowed for reliable evaluation of the liquefaction susceptibility of fine-grained soils. A well-documented database of in situ and index testing is now available for incorporating in future CPT- and SPT-based liquefaction triggering correlations. 相似文献
28.
RF Wideman YK Kirby CD Tackett NE Marson RW McNew 《Canadian Metallurgical Quarterly》1996,75(12):1587-1602
Cardio-pulmonary function was measured in male broilers reared on diets formulated to contain 1.5% arginine (NORMAL group) or 2.5% arginine (ARGININE group). A snare placed around the right pulmonary artery permitted acute shunting of the entire cardiac output (CO) through the left pulmonary artery, resulting in sustained increases in blood flow (BF) through the left lung in both groups. The unilateral increase in BF was accompanied by sustained increases in pulmonary arterial pressure (PAP) and pulmonary vascular resistance (PVR) in the NORMAL group. However, following initial transient increases in PAP and PVR in the ARGININE group, subsequent pulmonary vasodilation gradually reduced PVR, and thus PAP, in spite of the ongoing elevation of BF through the left lung. The capacity of the pulmonary vasculature in the ARGININE group to accommodate an increased BF at a normal PAP accounts for the previously reported lower incidence of pulmonary hypertension syndrome (PHS, ascites) in cold-stressed broilers fed supplemental dietary arginine. Hypoxemia and respiratory acidosis ensued rapidly in both groups after tightening the pulmonary artery snare, in spite of a compensatory increase in the respiratory rate. The gradual return of PVR and PAP to presnare levels in the ARGININE group did not eliminate the concurrent ventilation-perfusion mismatch caused by the increased rate of BF through the left lung. Tightening the pulmonary artery snare caused mean systemic arterial pressure (MAP) to drop from control levels of approximately 98 mm Hg to sustained hypotensive levels of approximately 65 mm Hg in both groups. This systemic hypotension was caused by decreases in CO and total peripheral resistance (TPR). The reduction in CO were caused by reduction in stroke volume (SV) rather than heart rate (HR), suggesting that acutely tightening the pulmonary artery snare increased PVR sufficiently to impede left ventricular filling. Accordingly, the maximum increment in PAP attainable by the right ventricle during acute increases in PVR apparently was inadequate to propel the entire CO through the pulmonary vasculature, setting the stage for the congestive right-sided pooling of blood routinely associated with PHS in broilers. 相似文献
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30.
Christensen Anne-Lise; Malmros Richard; Townes Brenda D. 《Canadian Metallurgical Quarterly》1987,1(2):45
After suffering a rupture of a left-sided aneurysm on the middle cerebral artery with prolonged arterial spasms, the prognosis for recovery of speech and motor functions of a 27-yr-old male patient was considered to be poor. Based on a Luria neuropsychological investigation that revealed many areas of preserved brain functions, rehabilitation efforts were directed toward training of specific abilities as well as compensatory skills using intact functions. This case demonstrates the interaction between the training program and the levels of motivation and persistence of the S and his family necessary to produce optimal rehabilitation outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献