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81.
An 81 year old right handed woman developed a left alien hand syndrome characterised by involuntary movements of choking and hitting the face, neck, and shoulder. The patient showed multiple disorders of primary sensation, sensory processing, hemispatial attention, and visual association, as well as a combination of sensory, optic, and cerebellar ataxia (triple ataxia) of the left arm in the absence of motor neglect or hemiparesis. Imaging studies disclosed subacute infarction in the right thalamus, hippocampus, inferior temporal lobes, splenium of corpus callosum, and occipital lobe due to right posterior cerebral artery occlusion. This rare syndrome should be considered as a "sensory" or "posterior" form of the alien hand syndrome, to be distinguished from the "motor" or "anterior" form described more commonly.  相似文献   
82.
The relationship of breathing movements to lung development in the ovine fetus was investigated by partially removing ribs on each side of the chest and closing the deficiencies with silicone membranes at 114 days of gestation; the increase in compliance of the chest wall that resulted caused blunting of the amplitude of phasic negative pressures recorded in the trachea to less than 10 torr. Compared to sham operated controls (n = 5), the lungs of the thoracoplasty group (n = 5) at term weighed significantly (P less than 0.05) less, both wet (1.5 +/- 0.2 v. 2.3 +/- 0.1% of body weight) and dry (0.14 +/- 0.01 v. 0.18 +/- 0.01% of body weight. In addition, DNA content of the thoracoplasty group was less than that of the control group (0.47 +/- 0.05 mg v. 0.72 +/- 0.20 mg). Distensibility of the left lung with air at 40 cmH20 was less than in the thoracoplasty group than in controls (10.0 +/- 2.0 v. 18.9 +/- 3.0 ml.kg-1 body weight) but no differences were found in the concentrations of saturated phosphatidylcholine in lung tissue and lavage fluid, in DNA concentrations or in the amount of lung water (as % of wet weight of lung). It is concluded that phasic negative pressures of normal intensity are necessary for normal development of the fetal lungs.  相似文献   
83.
Pyrroline-5-carboxylate reductase, which converts pyrroline-5-carboxylate to proline, has been identified in human erythrocytes. The level of pyrroline-5-carboxylate reductase activity in these cells is comparable to the activity levels of major erythrocyte enzymes. The physiologic function of the enzyme in erythrocytes cannot be related to its function in other tissues, i.e., producing proline for protein synthesis. We examined the kinetic properties of erythrocyte pyrroline-5-carboxylate reductase and compared them to the properties of the enzyme from proliferating cultured human fibroblasts. We found that the kinetic properties and regulation of the erythrocyte enzyme are distinctly different from those for human fibroblast pyrroline-5-carboxylate reductase. These characteristics are consistent with the interpretation that the function of the enzyme in human erythrocytes may be to generate oxidizing potential in the form of NADP+.  相似文献   
84.
Twelve patients completed a double-blind, crossover antiarrhythmic drug trial in which 300 mg of quinidine, 500 mg of procainamide, 100 mg of phenytoin, or placebo was given four times daily on subsequent weeks. Analysis of 24-hour Holter tapes with a computerized analysis system (Argus/H) permitted accurate counting of premature ventricular complexes (PVCs) subclassified according to coupling interval. No antiarrhythmic agent demonstrated a significant overall reduction in the number of PVCs, but both quinidine and procainamide showed a statistically significant (p less than 0.05) reduction of PVCs with coupling intervals less than 400 msec. This effect was noted both in isolated PVCs (quinidine only) and in PVCs that were part of a couplet or run (both drugs). These findings demonstrate that clinically important effects of procainamide and quinidine can occur in the absence of an overall reduction in the number of PVCs.  相似文献   
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The objective of this study was to determine the effects of fat supplementation from canola seed (CS) on ruminal fermentation and postruminal digestion of OM, carbohydrates, and energy of diets containing different levels of forage. Six ruminally and duodenally cannulated beef steers (354 kg +/- 18) were given ad libitum access to six isonitrogenous diets that were offered twice daily in a 6 x 6 Latin square design. Treatments were arranged as a 2 x 3 factorial with two forage levels (70 vs 30% of dietary DM as corn silage) and three forms of CS supplementation including no CS or CS added at 10% of dietary DM as whole CS treated with alkaline hydrogen peroxide or untreated crushed CS. Fat from CS provided 5% of dietary DM. The remaining dietary ingredients were corn, canola meal, molasses, and urea. No interactions (P > .05) between dietary forage level and CS supplementation were observed for ruminal characteristics or digestion of OM, carbohydrates, and energy in the rumen, postruminally, or in the total tract. Fat supplementation from CS did not affect (P > .05) DMI. With few exceptions, fat supplementation did not affect (P > .05) ruminal, postruminal, or total tract digestibilities of OM, structural and nonstructural carbohydrates, and GE. Ruminal disappearance of GE was decreased (P < .05) when diets were supplemented with fat from whole treated CS, and total tract digestibilities of OM and GE were decreased (P < .05) when diets were supplemented with fat from CS in either form. Ruminal pH, concentrations of NH3 N and total VFA, and molar proportions of acetate, propionate, and butyrate were not affected (P > .05) by fat supplementation. Results suggest that fat supplementation from CS (at 5% of dietary DM) as whole treated or untreated crushed had no negative effects on ruminal fermentation of OM, carbohydrates, or energy when steers were given ad libitum access to diets containing high or low forage.  相似文献   
88.
A multicylinder somatic shunt model for spiny, passive neurones is considered. The spines are modelled as a continuum (after Baer & Rinzel, 1991), coupled through the spread of dendritic voltage. A general solution is developed and a relationship governing the contribution of dendrites, soma, and spines to the voltage response is derived.  相似文献   
89.
BACKGROUND: The effects of dialysis inadequacy on patient survival and nutritional status and that of malnutrition on survival have not been clearly assessed. Studies comparing dose/mortality and morbidity curves on continuous ambulatory peritoneal dialysis (CAPD) and on haemodialysis (HD) are also needed, to assess adequate treatment on CAPD. METHODS: We have evaluated the effects of age, 13 pretreatment risk factors, serum albumin, transferrin, normalized protein catabolic rate, Kt/V, normalized weekly creatinine clearance, residual renal function and subjective global assessment of nutritional status on survival and morbidity, in a 3-year prospective study of 68 CAPD and 34 HD patients. RESULTS: Survivals did not differ for CAPD and HD patients. In the Cox hazard regression model, age, peripheral vasculopathy, serum albumin < 3.5 g/dl and Kt/V < 1.0/treatment on HD and < 1.7/week on CAPD were independent factors negatively affecting survival. On the contrary, adjusted survivals were not affected by gender, modality, other comorbid factors, normalized protein catabolic rate, or subjective global assessment of nutritional status. Persistence of residual renal function significantly improved survival. Observed and adjusted survival did not significantly differ for CAPD and HD patients with either low (HD, < 1.0/treatment; CAPD, < 1.7/week) or high ( > or = 1.0 and > or = 1.7) Kt/V. On HD, adjusted survivals were similar for 1.0 < or = Kt/V < 1.2 or > or = 1.2. On CAPD, Kt/V > or = 1.96/week was associated with definitely better survival, with only one death/23 patients versus 19/45, with Kt/V < or = 1.96. Survival was not different for 1.96 < or = Kt/V < 2.03 and > or = 2.03. Normalized weekly creatinine clearance and wKt/V were positively related on CAPD (r 0.39, P < 0.01) and wKt/V = 1.96 corresponded to 58 litres of normalized weekly creatinine clearance. CONCLUSIONS: Indices of adequacy were predictors of mortality and morbidity, both on CAPD and HD, whereas normalized protein catabolic rate and subjective global assessment of nutritional status were not. Serum albumin did not decrease during dialysis; hence its predictive effect for survival is due to the predialysis condition and not to dialysis-induced malnutrition.  相似文献   
90.
Aspiration pneumonia following surgically placed feeding tubes   总被引:1,自引:0,他引:1  
BACKGROUND: The enteral route is preferred in surgical patients requiring nutritional support; however, controversy surrounds the choice of location of feeding tube placement. Although jejunostomy has been commonly accepted as superior to gastrostomy for long-term nutritional support because of an assumed lower risk of aspiration pneumonia, recent studies suggest that reevaluation of common practices of surgical tube placement is warranted. PATIENTS AND METHODS: We conducted a retrospective chart review of gastrostomy and jejunostomy procedures from 1986 to 1993. Demographic information and complications related to the procedure were reviewed. Aspiration pneumonia was defined as respiratory symptoms, leukocytosis, and infiltrate on chest radiograph. RESULTS: Sixty-nine gastrostomies and 86 jejunostomies were performed during the study period. Six patients were diagnosed with aspiration pneumonia; 2 cases of which occurred with jejunostomy and 4 cases occurred with gastrostomy (P = not significant). CONCLUSIONS: There was no difference in rates of pulmonary aspiration or other complications between gastrostomy and jejunostomy. We suggest that when a surgically placed feeding tube is required, the determination of appropriate procedure be based on clinical factors such as the technical difficulty of the operation or long-term feeding goals.  相似文献   
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