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131.
To evaluate body weight as a determinant of cardiac structure and function in adolescents, 47 normotensive 13-year-old subjects were studied with M-mode echo duplex Doppler echocardiography (DE). They were separated by body weight into standard (greater than 55 kg) and lighter (less than 55 kg) groups. No subject had a blood pressure greater than 140/90. The differences between the groups in systolic (SBP) and diastolic (DBP) blood pressures, LV mass, left atrial size (LA), and peak aortic flow velocity (PAoV) were measured. (Formula: see text). Body weight strongly correlated with SBP in the entire study group (r = 0.66, P less than 0.001) but slightly less strongly with DBP (r = 0.48, P less than 0.001). Left ventricular filling indices such as peak early diastolic flow velocity, early diastolic filling integral, peak atrial flow velocity, and atrial filling integral were not significantly different between the groups. No significant differences in blood pressure, LV mass, LA size, or peak aortic flow velocity could be demonstrated when the subjects were subdivided on the basis of gender or presence or absence of family history of hypertension. Body weight appeared to be not only a strong predictor of blood pressure but also of cardiac structural and functional characteristics in adolescents.  相似文献   
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Insulin release from pancreatic islets is impaired in chronic renal failure (CRF), and this is due to the state of secondary hyperparathyroidism of CRF. This defect in association with resistance to the peripheral action of insulin-caused glucose intolerance in CRF. It has been suggested that the impaired insulin release induced by excess parathyroid hormone (PTH) is related to the ability of the hormone to augment calcium entry into the pancreatic islets, resulting in accumulation of calcium in the pancreas. Therefore, a calcium channel blocker may antagonize this effect of PTH, and hence normalize glucose tolerance in CRF. The present study examined this postulate by studying intravenous glucose tolerance and insulin release from pancreatic islets in normal and CRF rats and in CRF animals treated with the calcium channel blocker, verapamil. Rats with 42 days of CRF displayed impaired glucose tolerance, significant reduction (P less than 0.01) in insulin release by islets, and doubling of calcium content of the pancreas (P less than 0.01) as compared to normal rats. Simultaneous treatment of CRF rats with verapamil for 42 days resulted in normal glucose tolerance, higher blood insulin levels during glucose infusion, normal calcium content of the pancreas, and normal insulin secretion by the islets. Treatment of normal rats with verapamil for 42 days did not affect any of the parameters studied. The results show that the calcium channel blocker, verapamil, by preventing calcium accumulation in the pancreas, reversed the abnormalities in insulin release that occur in CRF. This effect allowed a greater rise in blood levels of insulin during glucose infusion in CRF rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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This article evaluates changes in the use of drug services and the corresponding costs when the conventional fee-for-service system for reimbursement of pharmacists under medicaid is replaced by a capitation system. The fee-for-service system usually covers ingredient costs plus a fixed professional dispensing fee. The capitation system provided a cash payment (which varied by aid category and season of the year) per Medicaid eligible the first of each month. We examined drug use and costs in two experimental rural counties during a 1-year preperiod in which the fee-for-service form of reimbursement was employed, as well as a 2-year postperiod in which the capitation system was used. We compared the results with use and cost patients in two other rural counties which remained on the fee-for-service system during the same 3-year period. Drug use was similar among control and experimental counties with the exception of nursing home patients; use in this category decreased under capitation and increased under fee-for-service. Using three measures of drug cost: 1) average cost of a day's drug therapy; 2) average drug costs per recipient; and 3) average Medicaid expenditures for drug services per recipient, we observed significant savings under the capitation reimbursement system as compared to the fee-for-service system. We attributed savings under capitation to shifts in prescribing and dispensing behavior, as well as changes in use by nursing home patients. Based upon these findings, the total savings resulting from implementing capitation would be approximately 16 percent compared to fee-for-service reimbursement.  相似文献   
137.
Rheumatoid arthritis causes synovitis in the cervical spine and injures skeletal structures at any level. Subluxations occur with pain and spinal cord dysfunction. Subluxations are common; neurological problems are less so, but death from subluxations is not common. However, once myelopathy is established, the natural history is poor. Advances in radiologic imaging through computed tomography and magnetic resonance imaging greatly assist anatomic assessment. Neurologic deterioration and pain are indications for surgery. Preoperative skeletal traction is often required to align the spine, and fusion techniques are used for stabilization.  相似文献   
138.
The visual system is highly susceptible to involvement in many systemic disorders. Disorders of tissues common to the eye and the hand, such as vascular, connective and neural, may have striking clinical signs in both. Thus signs in the hand may provide useful diagnostic clues in the assessment of disorders of the visual system. The hand may even be causative in traumatic or infective eye diseases. This review provides a schema for a suitable hand examination and documents the eye and hand features of various common and uncommon disorders. The importance to the ophthalmologist of a careful hand examination is emphasised.  相似文献   
139.
Extracorporeal shock wave lithotripsy (ESWL) is an accepted method of treatment for renal calculi. Complications are rare, although most patients experience temporary hematuria. Shock waves generated by a spark plug in a tubless lithotripter administered to stones placed into the renal pelves of dogs, resulted in interstitial renal hemorrhage developing acutely, and interstitial fibroblastic reactions chronically. The latter were linear, and were in the cortex and/or medulla. They resulted from organisation of the interstitial hemorrhages. In addition interstitial nephritis was present and this could be the result of the surgery, the stones, preexisting infection or the ESWL. Other organs were intact, with the exception of a hematoma in the large bowel of one dog. Lithotripsy, in this dog model, produced a spectrum of kidney injury.  相似文献   
140.
Half brothers from the same mother had congenital left sided posterolateral diaphragmatic hernias repaired in the neonatal period. The inheritance of diaphragmatic hernia should probably be based on the multifactorial hypothesis.  相似文献   
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