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991.
992.
993.
Intravenous glucose tolerance and plasma insulin response in children with homozygous β-thalassaemia
C. KATTAMIS. CH. THEODORIDIS E. KANAVAKIS 《Journal of paediatrics and child health》1982,18(3):186-187
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.
Clegg CH; Rulffes JT; Haugen HS; Hoggatt IH; Aruffo A; Durham SK; Farr AG; Hollenbaugh D 《International immunology》1997,9(8):1111-1122
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.
W. CH. Hecker R. Daum 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1970,327(1):864-870
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.
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.
BT Bloom J Kattwinkel RT Hall PM Delmore EA Egan JR Trout MH Malloy DR Brown IR Holzman CH Coghill WA Carlo AK Pramanik MA McCaffree PL Toubas S Laudert LL Gratny KB Weatherstone JH Seguin LD Willett GR Gutcher DH Mueller WH Topper 《Pediatrics》1997,100(1):31-38
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 =2000 g birth weight with established RDS, and the prevention arm enrolled infants of =29 weeks' gestation with birth weights <1250 g. INTERVENTION: Infants were randomly assigned to receive Infasurf (n = 303, treatment arm; n = 180, prevention arm) or Survanta (n = 305, treatment arm; n = 194, prevention arm) in accordance with the Survanta package insert instructions. OUTCOME MEASURES: We projected a 25% reduction between groups in the need for a third dose of surfactant for infants with established RDS, and a 25% reduction in the need for a second dose of surfactant for infants who received prophylactic surfactant. Secondary outcomes included the severity of RDS measured by inspired oxygen concentrations and mean airway pressure, air leaks, complications associated with surfactant administration, and survival to 36 weeks' postmenstrual age without the need for oxygen supplementation. RESULTS: In the treatment arm, there was no difference between groups in the number of infants requiring more than two doses of surfactant. The interval between doses was significantly longer for Infasurf, suggesting an increased duration of treatment effect. The inspired oxygen concentration and mean airway pressure were lower in the Infasurf infants during the first 48 hours in the treatment arm. In the prevention arm, there were no differences with respect to the number of surfactant doses. The dosing intervals were longer for Infasurf infants after the second dose. No difference in inspired oxygen or mean airway pressure was noted during the first 72 hours. There were no significant differences in the incidence of air leaks, complications associated with dosing, complications of prematurity, mortality, or survival without chronic lung disease in the prevention or treatment arm. CONCLUSIONS: Infants treated with Infasurf have a modest benefit in the acute phase of RDS. Infasurf seems to produce a longer duration of effect than Survanta. 相似文献
1000.
Metabolic activation of aromatic amines by human pancreas 总被引:4,自引:3,他引:4
Anderson KE; Hammons GJ; Kadlubar FF; Potter JD; Kaderlik KR; Ilett KF; Minchin RF; Teitel CH; Chou HC; Martin MV; Guengerich FP; Barone GW; Lang NP; Peterson LA 《Carcinogenesis》1997,18(5):1085-1092
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