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An enquiry into sudden infant death syndrome (SIDS) in 1987 furnished us with detailed epidemiological data for 281 cases that underwent a thorough post-mortem examination. This analysis uses these data to evaluate the role the autopsy plays in explaining sudden death. The cases were classified into three diagnostic groups: explained causes of death (group 1), unexplained deaths with anomalies (group 2), and no anomaly (group 3). These 281 cases show the three essential features that characterize SIDS: over-representation of males, increased deaths during the second and third months of life, and increased deaths during winter. The autopsy examination revealed that many of these deaths had a medical explanation. Almost half were assigned to group 1. At the time of autopsy, no precise pathology could be diagnosed for 147 deaths; of these, 140 showed histological anomalies. There were only seven sudden deaths for which no abnormal sign was evident at the autopsy. These results are compared with those of similar studies and discussed in connection with three factors: the initial selection of cases, the nature and degree of the investigations, and the possible interpretations of the symptoms uncovered.  相似文献   
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Studies on the development of automatic postural responses in both typically developing children and children with cerebral palsy were performed. With the appearance of "pull-to-stand" behavior, typically developing children first began to show muscle responses to platform movements in mainly the ankle muscles. With increased development, additional agonist muscles were added to the response pattern and a consistent distal to proximal sequence began to emerge. Well-organized responses were seen with the onset of independent stance and walking, along with the reduction of antagonist muscle co-activation. The older children with cerebral palsy who were pre-walkers had immature muscle activation patterns like those seen in the typically developing children at the pull-to- stand stage of development. These included disorganized muscle responses and increased frequency of coactivation of both proximal–distal and agonist–antagonist muscles. In order to determine if musculoskeletal constraints contributed to these response patterns, normal children were asked to stand in a crouched posture similar to that of children with CP. This caused postural muscle response patterns to more closely approximate those of children with spastic diplegia.  相似文献   
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The authors studied associations between ankle-brachial index (ABI) and subclinical atherosclerosis in the Multi-Ethnic Study of Atherosclerosis. Participants included 3,458 women (average age = 62.6 years) and 3,112 men (average age = 62.8 years) who were free of clinically evident cardiovascular disease. Measurements included ABI, carotid artery intima-media thickness, and coronary artery calcium assessed with computed tomography. Five ABI categories were defined: <0.90 (definite peripheral arterial disease (PAD)), 0.90-0.99 (borderline ABI), 1.00-1.09 (low-normal ABI), 1.10-1.29 (normal ABI), and > or =1.30 (high ABI). Compared with that in men with normal ABI, significantly higher internal carotid artery intima-media thickness was observed in men with definite PAD (1.58 vs. 1.09; p < 0.001), borderline ABI (1.33 vs. 1.09; p < 0.001), and low-normal ABI (1.18 vs. 1.09; p < 0.001) after adjustment for confounders. Fully adjusted odds ratios for a coronary artery calcium score greater than 20 decreased across progressively higher ABI categories in both women (2.85 (definite PAD), 1.27 (borderline ABI), 1.11 (low-normal ABI), 1.00 (normal ABI; referent), and 0.78 (high ABI); p for trend = 0.0002) and men (3.26 (definite PAD), 1.72 (borderline ABI), 1.14 (low-normal ABI), 1.00 (normal ABI; referent), and 1.43 (high ABI); p for trend = 0.0002). These findings indicate excess coronary and carotid atherosclerosis at ABI values below 1.10 (men) and 1.00 (women) and may imply increased risk of cardiovascular events in persons with borderline and low-normal ABI.  相似文献   
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OBJECTIVE: This study was undertaken to determine the quantitative augmentation response in several veins examined in a cohort assembled to permit comparisons by sex, age, and ethnicity, under normal conditions and in the presence of obstruction, with and without trophic changes. METHOD: The common femoral vein, superficial femoral vein, sapheno-femoral junction, popliteal vein, sapheno-popliteal junction, and posterior tibial vein were studied with duplex ultrasonographic scanning. Augmentation response was elicited with use of an automated cuff inflator. Mean level of each response was analyzed according to patient sex, age, and ethnicity, each adjusted for the other two. Normal values were compared with those obtained from legs with venous obstructive disease, with or without signs of trophic changes. RESULTS: Decreased augmentation response was noted only in the sapheno-femoral junction and sapheno-popliteal junction, and was smaller in women. Augmentation response was slightly increased in the oldest age group (>70 years) in the common femoral vein, superficial femoral vein, popliteal vein, and posterior tibial vein. The highest augmentation response was found in Asian subjects, in the common and superficial femoral veins and the sapheno-femoral and sapheno-popliteal junctions; and the smallest augmentation response was found in African American subjects, in these same veins and junctions. Differences in vein diameters may explain these findings, ie, smaller diameters in Asians and larger diameters in African Americans. Most important, compared with normal values, augmentation response was decreased in legs with venous obstructive disease only when trophic changes were present. CONCLUSION: Like quantification of reflux, quantitative evaluation of the augmentation response may help in diagnosis of venous obstructive disease when trophic changes are present.  相似文献   
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