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991.
992.
993.
ABSTRACT. Glucose tolerance and insulin secretion were studied after intravenous glucose load in 10 normal and 27 children with homozygous β-thalassaemia of whom 11 received 5–20 units of blood (1.25–5g total iron) and 16 received 50–60 blood units (12.5–40g total iron). Fasting blood glucose and insulin levels were similar in normal and thalassaemic children. Differences were found at 10 and 20 minutes of intravenous glucose administration both in glucose blood levels. (which were considerably higher) and insulin levels (which were significantly lower), in thalassaemic patients compared to normal children. Evidence of depression of pancreatic function was found in three out of 11 patients, with low and in three out of 16 patients with severe iron load. These findings suggest that in thalassaemia pancreatic impairment is not always directly related to the degree of iron overload.  相似文献   
994.
Thymus dysfunction and chronic inflammatory disease in gp39 transgenic mice   总被引:2,自引:0,他引:2  
Expression of gp39 on activated T cells provides a co-stimulatory signal in peripheral lymphoid tissue that regulates humoral and cell- mediated immunity. The function of gp39 and its receptor CD40 in thymus remains uncertain. Here we report that overexpression of gp39 in transgenic mouse thymus caused a dose-dependent decline in thymocyte numbers (> 500 fold), loss of cortical epithelium and expansion of CD40+ medullary cells. Transplantation of transgenic bone marrow into normal mice indicated that gp39 significantly diminished thymocyte viability in the context of a 'normal' thymic environment. The peripheral tissues of transgenic mice also accumulated abnormalities in a transgene dose-dependent manner that involved inflammation and lymphoid tissue hypertrophy. Animals with the highest transgene copy numbers acquired a lethal inflammatory bowel disease marked by the infiltration of gp39+ T cells and CD40+ cells into diseased tissues. Examination of cells overexpressing gp39 suggested that these defects were caused, in part, by the saturation of a mechanism that sequesters gp39 inside non-activated cells and thus protects the immune system from inappropriate gp39-CD40 interaction. These results establish a regulatory role for gp39 in thymus function and a causal relationship in mediating chronic inflammatory disease.   相似文献   
995.
996.
Zusammenfassung Es wird die Meinung vertreten, daß beim wachsenden Organismus es einen grundsätzlichen Indikationsfehler bedeutet, wenn bei gelenknahen oder Gelenkfrakturen nicht die exakte Rekonstruktion der frakturierten Skeletteile vorgenommen wird. Dieses kann in den meisten Fällen nur durch eine Operation geschehen. Diese Forderung wird im Detail erläutert bei der Schenkelhalsfraktur, der subtrochantären Oberschenkelfraktur, der suprakondylären Femurfraktur und der distalen Humerusfraktur.
Summary The opinion is advanced that in the growing organism it is a fundamental mistake in indication not to perform accurate reconstruction of the fractured parts in fractures of or near a joint. In most cases this can only be done by operation. This postulate is illustrated in detail in the case of femoral neck fracture, subtrochanteric fracture of the femur, supracondylar fracture of the femur and distal fracture of the humerus.
  相似文献   
997.
Choledocholithiasis: treatment with extracorporeal shock wave lithotripsy   总被引:2,自引:0,他引:2  
In a patient with choledocholithiasis, a duodenal diverticulum precluded endoscopic retrograde bile duct cannulation. A transhepatic catheter was used to opacify the bile ducts and to guide the endoscopic sphincterotome into the major duodenal papilla. Because limited sphincterotomy did not allow extraction or spontaneous passage of the common duct stones, extracorporeal lithotripsy was performed. Following fragmentation, the stones passed spontaneously and without complications.  相似文献   
998.
Since oxygen has to be given to most children in developing countries on the basis of clinical signs without performing blood gas analyses, possible clinical predictors of hypoxaemia were studied. Sixty nine children between the ages of 2 months and 5 years admitted to hospital with acute lower respiratory tract infection and an oxygen saturation (Sao2) < 90% were compared with 67 children matched for age and diagnosis from the same referral hospital with an Sao2 of 90% or above (control group 1), and 44 unreferred children admitted to a secondary care hospital with acute lower respiratory infection (control group 2). Using multiple logistic regression analysis, sleepiness, arousal, quality of cry, cyanosis, head nodding, decreased air entry, nasal flaring, and upper arm circumference were found to be independent predictors of hypoxaemia on comparison of the cases with control group 1. Using a simple model of cyanosis or head nodding or not crying, the sensitivity to predict hypoxaemia was 59%, and the specificity 94% and 93% compared to control groups 1 and 2, respectively; 80% of the children with an Sao2 < 80% were identified by the combination of these signs. Over half of the children with hypoxaemia could be identified with a combination of three signs: extreme respiratory distress, cyanosis, and severely compromised general status. Further prospective validation of this model with other datasets is warranted. No other signs improved the sensitivity without compromising specificity. If a higher sensitivity is required, pulse oximetry has to be used.  相似文献   
999.
OBJECTIVE: To compare the relative safety and efficacy of Infasurf (calf lung surfactant extract; ONY, Inc, Amherst, NY, IND #27169) versus Survanta (Beractant, Ross Laboratories, Columbus, OH) in reducing the acute severity of respiratory distress syndrome (RDS) when given at birth and to infants with established RDS. DESIGN: A prospective, randomized, double-blind, multicenter clinical trial. SETTING: Thirteen neonatal intensive care units participated in the treatment arm: seven of these concurrently participated in the prevention arm. PATIENTS: The treatment arm enrolled infants of 相似文献   
1000.
Metabolic activation of aromatic amines by human pancreas   总被引:4,自引:3,他引:4  
Epidemiologic studies have suggested that aromatic amines (and nitroaromatic hydrocarbons) may be carcinogenic for human pancreas. Pancreatic tissues from 29 organ donors (13 smokers, 16 non-smokers) were examined for their ability to metabolize aromatic amines and other carcinogens. Microsomes showed no activity for cytochrome P450 (P450) 1A2-dependent N-oxidation of 4-aminobiphenyl (ABP) or for the following activities (and associated P450s): aminopyrine N-demethylation and ethylmorphine N-demethylation (P450 3A4); ethoxyresorufin O- deethylation (P450 1A1) and pentoxyresorufin O-dealkylation (P450 2B6); p-nitrophenol hydroxylation and N-nitrosodimethyl-amine N-demethylation (P450 2E1); lauric acid omega-hydroxylation (P450 4A1); and 4- (methylnitrosamino)-1-(3-pyridyl-1-butanol) (NNAL) and 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) alpha-oxidation (P450 1A2, 2A6, 2D6). Antibodies were used to examine microsomal levels of P450 1A2, 2A6, 2C8/9/18/19, 2E1, 2D6, and 3A3/4/5/7 and epoxide hydrolase. Immunoblots detected only epoxide hydrolase at low levels; P450 levels were <1% of liver. Microsomal benzidine/prostaglandin hydroperoxidation activity was low. In pancreatic cytosols and microsomes, 4-nitrobiphenyl reductase activities were present at levels comparable to human liver. The O-acetyltransferase activity (AcCoA- dependent DNA-binding of [3H]N-hydroxy-ABP) of pancreatic cytosols was high, about twothirds the levels measured in human colon. Cytosols showed high activity for N-acetylation of p-aminobenzoic acid, but not of sulfamethazine, indicating that acetyltransferase-1 (NAT1) is predominantly expressed in this tissue. Cytosolic sulfotransferase was detected at low levels. Using 32P-post-labeling enhanced by butanol extraction, putative arylamine-DNA adducts were detected in most samples. Moreover, in eight of 29 DNA samples, a major adduct was observed that was chromatographically identical to the predominant ABP- DNA adduct, N-(deoxyguanosin-8-yl)-ABP. These results are consistent with a hypothesis that aromatic amines and nitroaromatic hydrocarbons may be involved in the etiology of human pancreatic cancer.   相似文献   
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