The Troms?o heart study. Methods and main results of the cross-sectional study

The mortality from coronary heart disease (CHD) in Norway increased rapidly during 1951-70, the highest mortality rates as well as the most rapid increases being found in Northern Norway. Several surveys of CHD were then planned, one of them is reported here. All men, 20-49 years of age, living in the municipality of Troms?o, Troms county, were called up for examination. In total, 6595 men, 74.4% of those invited, were examined. Cholesterol, triglyceride and Hb values, BP, body weight and height, the percentage of smokers, and cigarette consumption have been tabulated according to area, age, work schedule, health condition, physical activity and ethnic background. The results suggest that the relatively high mortality from CHD in Northern Norway is associated with high serum cholesterol concentrations as well as a relatively high prevalence of smoking. During the screening there were indications of changes in dietary habits in the municipality, presumably as a result of accompanying publicity.     

Gas embolism due to intravenous FC 80 liquid fluorocarbon

Lethal gas embolism always occurs after FC 80 liquid fluorocarbon is injected intravenously (0.1 ml/kg body mass) in dogs breathing room air but not in dogs breathing oxygenated FC 80 liquid fluorocarbon. Gas embolism is not prevented in dogs that have been injected intravenously with FC 80 when they are exposed to 2 ATA (atmospheres absolute) 20% 02-80% N2, 9 ATA 5% O2-95% He, or 1 ATA 100%, O2. In dogs that die of FC 80-induced gas embolism, free gas in the right atrium contains approximately 0.5 g FC 80/liter, and Po2 and Pco2 in the gas are in equilibrium with their corresponding tensions in right atrial blood. These observations are consistent with the hypothesis that PFC 80 in alveolar gas does not equilibrate with PFC 80 (55 mmHg) in blood. The total gas tension in pulmonary capillary blood containing FC 80 and its vapor thus exceeds the total tension of alveolar gases (atmospheric pressure). Bubbles of O2, CO2, N2, FC 80, and water vapor form in the regions of the pulmonary capillary bed where the total tension of gases dissolved in blood exceeds the absolute blood pressure.     

Experimental autoimmune myasthenia gravis: a sequential and quantitative study of the neuromuscular junction ultrastructure and electrophysiologic correlations

Neuromuscular junction ultrastructure in rat forelimb digit extensor muscle was sequentially and quantitatively investigated in experimental autoimmune myasthenia gravis (EAMG). Experimental animals were immunized with highly purified eel electroplax acetylcholine receptor protein plus complete Freund's adjuvant and B pertussis vaccine; control animals received only adjuvant and vaccine. During the first 7 days (latent period) after immunization end-plate structure and neuromuscular transmission remained normal in the experimental group. Between day 7 and 11 (acute phase) mononuclear cells infiltrated those regions of muscle where the end-plates were located and there was intense degeneration of the postsynaptic regions with splitting away of abnormal junctional folds from the underlying muscle fibers. Macrophages entered the gaps thus formed and removed the degenerating folds by phagocytosis. The nerve terminals were displaced from their usual location but maintained their structural integrity. Neuromuscular transmission was blocked in many muscle fibers. Miniature end-plate potentias (MEPPs), detectable in only a few fibers, were of abnormally low amplitude. After day 11 (chronic phase) the nerve terminals returned to the highly simplified postsynaptic folds became reconstituted and again degenerated. Immature junctions with poorly differentiated postsynaptic regions and nerve sprouts near end-plates were also observed. In two animals relapsing during the chronic phase degeneration of the postsynaptic folds was more intense than in the other chronic-phase animals. The posysynaptic membrane length and length per unit area and the MEPP amplitudes were significantly decreased in all chronic phase animals and the decreases were greater in the relapsing than in the non-lapsing animals. Minor morphometric alterations were also observed in the nerve terminals. These might have been secondary to the postsynaptic changes. The postsynaptic region is the primary target of the autoimmune reaction in EAMG. The ultrastructural, morphometric and electrophysiological abnormalities of the end-plate in chronic EAMG resemble those which have been observed in human myasthenia gravis.     

Effects of radiation therapy on growing long bones

Characteristic radiographic changes were seen in six of 14 children who received radiation therapy to the epiphyseal plate of a long bone. These changes, which include metaphyseal sclerosis, metaphyseal fraying, and epiphyseal plate widening, resemble rickets. In three patients, these changes were followed by development of a broad metaphyseal band of increased density. The absence of metaphyseal changes may indicate sterilization of cartilage cells and may be predictive of significant limb shortening.     

Age-related differences in switching between cognitive tasks: Does internal control ability decline with age?

The present study tested the hypothesis that older adults establish a weaker task set than younger adults and therefore rely more on stimulus-triggered activation of task sets. This hypothesis predicts that older adults should have difficulty with task switches, especially when the stimuli-responses are associated with multiple, competing tasks. Weak task preparation, however, could actually benefit older adults when performing an unexpected task. The authors tested this prediction in Experiment 1 using a repeating AABB task sequence, with univalent and bivalent stimuli intermixed. On some univalent trials, participants received an unexpected task. Contrary to the authors' predictions, expectancy costs were not smaller for older adults. Similar findings were obtained in Experiments 2 and 3, in which the authors used a task-cueing paradigm to more strongly promote deliberate task preparation. The authors found no disproportionate age effects on switch costs but did find age effects on bivalence costs and mixing costs. The authors conclude that older adults do experience extra difficulty dealing with stimuli associated with 2 active tasks but found no evidence that the problem specifically stems from an increased reliance on bottom-up task activation rather than top-down task preparation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

D优化的实验设计在IC工艺和器件优化中的应用

论述了实验设计技术与ＴＣＡＤ相结合用于半导体工艺和器件性能优化的新途径，它可以极大地减少开发和研制新工艺、新器件的时间和成本。