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141.
This study examined the effects of cardiomyoplasty with vascular delay on canine normal and depressed left ventricular (LV) function. To improve viability of the latissimus dorsi muscle (LDM), vascular delay was performed 2 weeks before cardiomyoplasty in 10 mongrel dogs. Two weeks after cardiomyoplasty, LV function was evaluated by simultaneously measuring LV and aortic pressure, and aortic flow. The LDM was stimulated at a ratio of 1:4-1:7 synchronously with ventricular systole. Microspheres (90 mu) were sequentially injected into the left coronary artery to depress LV function. Data were acquired and analyzed on a beat to beat basis. Results were as follows: LDM stimulation significantly augmented LV systolic pressure (LVSP) from 138 +/- 2 to 161 +/- 2* mmHg, the peak rate of change of LV pressure (+dP/dt) from 1888 +/- 46 to 2584 +/- 43* mmHg/sec, aortic systolic pressure (AoSP) from 140 +/- 2 to 159 +/- 2* mmHg, stroke volume (SV) from 11.2 +/- 0.3 to 13.3 +/- 0.3* ml, stroke work (SW) from 19 +/- 1 to 26 +/- 1* gm.m, peak aortic flow (P Qa) from 5542 +/- 142 to 7190 +/- 161* ml/min, and decreased -dP/dt from -1683 +/- 31 to -1689 +/- 49* mmHg/sec (* = p < 0.05). Microsphere injections depressed LV function, but did not affect the magnitude of the net changes between stimulated and nonstimulated beats. However, the percent changes significantly increased. Preconditioning of LDM with vascular delay augments cardiac function in LDM assisted beats. This improved performance was present in both normal as well as depressed LV function groups. Thus, investigations of cardiomyoplasty may not necessarily require a model of severe myocardial dysfunction. Vascular delay offers an important preconditioning method of LDM to augment cardiac function in cardiomyoplasty.  相似文献   
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Prominence of the extraaxial space occasionally is encountered in infants referred for ultrasonography to exclude hydrocephalus. The interpretation of this finding can be problematic. We examined the width of the extraaxial compartment in 82 normal newborn infants. Scanning technique was optimized for viewing the near field, and the extraaxial space was measured over the cerebral convexities. Correlation was made with demographic variables. Measurements varied from 0 to 3.3 mm (mean, 1.6 mm), with slight negative linear relationship to gestational age. We conclude that small amounts of extraaxial fluid, up to 3.3 mm in width on scans, are common and normal in newborn infants.  相似文献   
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Social class differences in health are seen at all ages, with lower socioeconomic groups having greater incidence of premature and low birthweight babies, heart disease, stroke, and some cancers in adults. Risk factors including lack of breast feeding, smoking, physical inactivity, obesity, hypertension, and poor diet are clustered in the lower socioeconomic groups. The diet of the lower socioeconomic groups provides cheap energy from foods such as meat products, full cream milk, fats, sugars, preserves, potatoes, and cereals but has little intake of vegetables, fruit, and wholewheat bread. This type of diet is lower in essential nutrients such as calcium, iron, magnesium, folate, and vitamin C than that of the higher socioeconomic groups. New nutritional knowledge on the protective role of antioxidants and other dietary factors suggests that there is scope for enormous health gain if a diet rich in vegetables, fruit, unrefined cereal, fish, and small quantities of quality vegetable oils could be more accessible to poor people.  相似文献   
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Posterior laryngeal clefts (PLCs) are described in the literature as rare laryngeal abnormalities. The authors believe type I clefts are much more common than previously reported. In two busy pediatric tertiary care centers, such clefts are the second most common congenital laryngeal finding at rigid endoscopy, second only to laryngomalacia. PLCs frequently present with symptomatology that can be attributed to other common disease processes and are often undiagnosed unless the surgeon maintains a high index of suspicion and specifically examines the posterior glottis by palpation during microlaryngoscopy. This report presents a series of 41 patients with type I PLCs, reviews their subtle and often confusing presenting signs and symptoms, and describes a simple yet reliable method of diagnosis.  相似文献   
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