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91.
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.  相似文献   
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The relationship between homovanillic acid (HVA), vanillylmandelic acid (VMA), and creatinine in the urine of 6 month old babies has been studied and reference ranges in the form of centiles constructed for HVA and VMA against creatinine. Over 10,000 urine samples were collected from babies in four health districts in the north of England. HVA and VMA concentration, either independently or when divided by creatinine concentration, were dependent upon the absolute concentration of creatinine in the sample. After adjustment for creatinine significant differences in the mean concentration of HVA were found between sexes. No such differences were found for VMA. HVA and VMA were also found to be age dependent. Centiles were constructed using a procedure which makes no distributional assumptions about the data. The net effect of utilising these centiles was to increase the predictive value of a positive screening test from 20% to 40% without any increase in the false negative rate.  相似文献   
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The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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It was recently reported by Buhot et al. that presession cholinergic disruption with scopolamine decreases time spent in proximity to novel objects while increasing locomotor behavior. Male Long-Evans rats (Rattus norvegicus, 80 days old) were given low-light access to an arena containing objects but were not forced to remain in the arena. On day 1, each subject was injected with saline (SAL). This session was used for familiarization with the apparatus and procedure. On days 2 and 3, four groups were given saline (SAL) or scopolamine (SCO, 1 mg/kg or 0.25 mg/kg), resulting in SAL-SAL, SAL-SCO, SCO-SAL, and SCO-SCO groups. Videotapes of these sessions were scored according to a standard protocol that allows separate quantification of locomotion, general activity, and object interaction behaviors. Scopolamine suppressed object investigation (both gross contact measures and indices of interaction character) whenever present. In contrast to Buhot et al. (using a forced-exploration situation), in this free-exploration context SCO also suppressed locomotor behavior. This study supports the conclusion that anticholinergics impair information gathering instead of affecting memory directly, which calls into question memory-related explanations of cholinergic treatments.  相似文献   
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Previous reports have indicated that a majority of the population has asbestos bodies within their lungs. These studies generally have been carried out using cohorts from urban environments. The present study compares the asbestos body levels from three unique cohorts: (1) a nonoccupationally exposed group from a large urban environment having a relatively low asbestos content, (2) patients with lung cancer from a nonurban setting, and (3) amosite asbestos workers, who worked and lived in a rural setting. The number of asbestos bodies in both the urban nonoccupationally exposed group and the patients with lung cancer was generally found to be low or below limits of detectability, with the exceptions being those persons in whom an occupational exposure was eventually found. The ferruginous body content of the occupationally exposed group varied considerably between individuals as well as between sites within the same individual.  相似文献   
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Background Escobar syndrome or multiple pterygium syndrome is characterized by a web across every flexion crease in the extremities, most notably the popliteal space. In addition, this syndrome is associated with two other structural anomalies: a vertical talus and congenital lordoscoliosis. We present a case report of a patient with Escobar syndrome who was initially managed conservatively and subsequently had severe and debilitating progression and respiratory decompensation ultimately requiring surgical intervention.Study Design Case report.Methods After preoperative evaluation by a pediatrician, pulmonologist, and otolaryngologist, the patient underwent one-stage anterior and posterior spinal fusion with instrumentation as well as multiple osteotomies, rib resections, and vertebrectomies.Results The patient’s postoperative course was complicated by wound necrosis requiring irrigation and debridement, a urinary tract infection, and a tracheostomy for persistent atelectasis. The patient eventually recovered from all complications. There were never any focal neurologic deficits. The patient had a 3-year follow-up with radiographically confirmed maintenance of correction. Fusion was obtained in the anterior and posterior segments. Clinically, the patient is able to stand upright, can participate in functional activities, and has not required any pain medication. The patient’s functional vital capacity improved from 23% predicted preoperatively to 60% predicted postoperatively.Conclusions Patients with severe spinal deformity secondary to Escobar syndrome can be successfully treated surgically. We propose early surgical intervention in this group to prevent curve progression, restrictive lung disease, and the need for complex salvage procedures.  相似文献   
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