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P Pencharz J Beesley P Sauer J Van Aerde U Canagarayar J Renner M McVey D Wesson P Swyer 《The American journal of clinical nutrition》1989,50(6):1395-1400
The effects of nonprotein energy source (ie, glucose only vs glucose and lipid) on nitrogen retention and total-body protein turnover were studied in 20 parenterally fed newborn infants. All infants received approximately 3 g amino acids and 80-90 kcal.kg body wt.d. Total-body protein synthesis was estimated by using three constant-infusion, end-product methods: enrichment of urinary urea and ammonia in response to a [15N]glycine label and exhaled carbon dioxide enrichment in response to a [1-13C]leucine label. No differences were seen in nitrogen retention between the two energy sources. The estimate of total-body protein turnover obtained from the 13C label was similar to that obtained with the [15N]urea label. No differences in turnover rates were observed between the two diet groups. Use of the glucose-plus-lipid fuel system enhanced energy storage and the reutilization of amino acid for protein synthesis. 相似文献
995.
The authors present 50 cases of cervical spondylotic myelopathy treated by anterior or posterior approach. To assess the severity of the pre- and postoperative neurological symptoms, they define an original ten-point classification scale taking into account gait and urinary disturbance, ability to manipulate objects and pain. With C2-C7 laminectomy, 60% of the patients are improved, essentially for walk. A few cases only (14%) are upgraded for upper limbs function. The authors conclude that this surgical treatment should be applied only when there is a multi-level narrowed canal and predominant lower limbs deficits. The efficacy of the anterior approach depends on complete removal of osteophytes. In cases with complete osteophytectomy, this surgical treatment can improve both the upper and lower limbs function and 77.8% good results are obtained. In a few cases it may be necessary to use both approach successively. Discriminant analysis applied to 12 factors shows that pre-operative scores of upper and lower limbs and sagittal diameter of spinal canal are the most important factors for neurological prognosis. 相似文献
996.
A series of C(3)-cyclopropyl cephems and carbacephems has been prepared by palladium catalyzed addition of diazomethane to the corresponding C(3)-vinyl derivatives. The phenylglycyl cyclopropyl cephem derivatives exhibit better Gram-positive activity than cephalexin or cefaclor, while the aminothiazole oxime cyclopropyl cephem derivatives were not as active as the corresponding C(3)-vinyl cephems. 相似文献
997.
R D Montgomery 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1989,83(6):724-728
The clinical profile of tropical spastic paraparesis (TSP), described in scattered tropical and subtropical territories over the past 30 years, has been more clearly defined since the discovery of its direct association with human T lymphotropic virus type 1 (HTLV-1). A chronic disease of adults, commoner in women, it usually presents as a progressive spastic paraparesis with sphincter disturbance, sometimes with backache and lower limb sensory disorder. Most cases are chair-bound within 10 years. Histology reveals a chronic lymphocytic meningomyelopathy, predominantly in the spinal cord, together with long tract demyelination and hyalinoid thickening of the media and adventitia of small blood vessels. Geographical areas of high prevalence of TSP are known in the Caribbean, South America, South Africa, southern Japan, the Seychelles and probably in India, and it is sparsely endemic elsewhere. The virus appears to exist within lymphocytes for long periods. Vertical transmission occurs postnatally, and sexual and transfusion infection are also recognized, but much remains to be clarified regarding its pathogenesis and epidemiology. 相似文献
998.
The hepatotropic effect of nonsteroidal anti-inflammatory drugs (NSAID) such as indomethacin, voltaren, piroxicam, phenylbutazon, mefenamic acid was studied. It was found that according to their level of the pharmacological protection of the liver against tetrachlormethan these agents may be arranged in the following sequence: mefenamic acid, phenylbutazon, voltaren, piroxicam. The hepatoprotective effect of NSAID correlates with the antioxidant properties and fails to correlate with the antioxidant ones. The hepatotoxic effect of NSAID was determined by their ability to suppress synthesis of prostaglandins. 相似文献
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