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21.
Background The clinical course in acute necrotizing pancreatitis is mainly determined by bacterial infection of pancreatic and peripancreatic necrosis. The effect of two antibiotic regimens for early and late treatment was investigated in the taurocholate model of necrotizing pancreatitis in the rat. Materials and methods Seventy male Wistar rats were divided into five pancreatitis groups (12 animals each) and a sham-operated group (10 animals). Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals received two different antibiotic regimes (20 mg/kg imipenem or 20 mg/kg ciprofloxacin plus 20 mg/kg metronidazole) early at 2, 12, 20, and 28 h after induction of pancreatitis or late at 16 and 24 h after induction of pancreatitis or no antibiotics (control). Animals were examined after 30 h for pancreatic and extrapancreatic infection. Results Early and late antibiotic treatment with both regimes could significantly reduce pancreatic infection from 58 to 8–25%. However, extrapancreatic infection was only reduced by early antibiotic therapy. While quinolones also reduced bacterial counts in small and large bowel, imipenem did not. Conclusions In our animal model of necrotizing pancreatitis, early and late treatment with ciprofloxacin/metronidazole and imipenem reduce bacterial infection of the pancreas. Extrapancreatic infection, however, is reduced significantly only by early antibiotic treatment. The effectivity of early antibiotic treatment in the clinical setting should be subject to further investigation with improved study design and sufficient patient numbers.  相似文献   
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Acute static toxicity experiments have been performed under normoxic and hypoxic conditions. The test animals used were adults of the groundwater-adapted copepod Parastenocaris germanica. The animals originated from a sandy, gravelly phreatic aquifer of the Meuse valley in The Netherlands. Toxicants applied were pentachlorophenol, 3,4-dichlorophenol, zinc, and cadmium. The results were statistically evaluated by a log-logistic model. LC50 and LC5 values with 95% confidence limits were calculated. Response models of application under both oxygen conditions were compared. The influence of ambient oxygen concentration on sensitivity appeared to be very small; only in the case of pentachlorophenol were hypoxic and normoxic models slightly but significantly different. Comparisons with the sensitivity of other organisms are made and the results are discussed against the specific physiological adaptations of the organisms to groundwater conditions.  相似文献   
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25.
Renal lesions have repeatedly been described in Wilson’s disease (WD). We investigated the excretion of total protein, albumin, low (LMW) and high molecular weight (HMW) proteins, N-acetyl-β-D-glucosaminidase (NAG), and calcium, as well as creatinine clearance, in 24-h urine samples of 41 patients with WD aged 6 – 37 (mean 17) years who had been treated for a period of 0 – 15 (mean 4.5) years with D-penicillamine (900 mg/day). The amount of all protein excreted was significantly increased compared with controls, 39% of patients presenting with total proteinuria more than two standard deviations from the mean of controls. The changes in protein excretion depended on the duration of treatment. LMW proteinuria was elevated almost exclusively in the first 2 years after the start of treatment, indicating early tubular damage. This is supported by an initially high excretion of β2-microglobulin, NAG, and calcium. Increased excretion of HMW proteins, including albumin, persisted over longer periods, which suggests glomerular injury in some patients, possibly related to the use of D-penicillamine. Creatinine clearance remained roughly within normal limits. We propose that renal function should regularly be checked in patients with WD. Received October 26, 1995; received in revised form August 27, 1996; accepted September 20, 1996  相似文献   
26.
Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder.  相似文献   
27.
Current dietary therapy for long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) or trifunctional protein (TFP) deficiency consists of fasting avoidance, and limiting long-chain fatty acid (LCFA) intake. This study reports the relationship of dietary intake and metabolic control as measured by plasma acylcarnitine and organic acid profiles in 10 children with LCHAD or TFP deficiency followed for 1 year. Subjects consumed an average of 11% of caloric intake as dietary LCFA, 11% as MCT, 12% as protein, and 66% as carbohydrate. Plasma levels of hydroxypalmitoleic acid, hydroxyoleic, and hydroxylinoleic carnitine esters positively correlated with total LCFA intake and negatively correlated with MCT intake suggesting that as dietary intake of LCFA decreases and MCT intake increases, there is a corresponding decrease in plasma hydroxyacylcarnitines. There was no correlation between plasma acylcarnitines and level of carnitine supplementation. Dietary intake of fat-soluble vitamins E and K was deficient. Dietary intake and plasma levels of essential fatty acids, linoleic and linolenic acid, were deficient. On this dietary regimen, the majority of subjects were healthy with no episodes of metabolic decompensation. Our data suggest that an LCHAD or TFP-deficient patient should adhere to a diet providing age-appropriate protein and limited LCFA intake (10% of total energy) while providing 10-20% of energy as MCT and a daily multi-vitamin and mineral (MVM) supplement that includes all of the fat-soluble vitamins. The diet should be supplemented with vegetable oils as part of the 10% total LCFA intake to provide essential fatty acids.  相似文献   
28.
A series of step-tracking experiments was conducted before, during, and after a 3-week space mission to assess the effects of prolonged microgravity on a non-postural motor-control task. In- and post-flight accuracy was affected only marginally. However, kinematic analyses revealed a considerable change in the underlying movement dynamics: too-small force and, thus, too-low velocity in the first part of the movements was mainly compensated by lengthening the deceleration phase of the primary movement, so that accuracy was regained at its end. The observed in-flight decrements in peak velocity and peak acceleration point to an underestimation of mass, in agreement with the re-interpretation hypothesis of Bock et. al. Post-flight no reversals of the in-flight changes (negative aftereffects) were found. Instead, there was a general slowing down, which could be due to post-flight physical exhaustion.  相似文献   
29.
A recombinant (r)-Salmonella typhimurium aroA vaccine strain was constructed which secretes the naturally somatic protein of Listeria monocytogenes, superoxide dismutase (SOD), by the HlyB/HlyD/TolC export machinery. Vaccine efficacy of the SOD-bearing carrier strain was compared with that of the p60-secreting construct, S. typhimurium p60s (J. Hess, I. Gentschev, D. Miko, M. Welzel, C. Ladel, W. Goebel, and S. H. E. Kaufmann, Proc. Natl. Acad. Sci. USA 93:1458-1463, 1996). Vaccination of mice with both constructs induced protection against a lethal challenge with the intracellular pathogen, L. monocytogenes. While the somatic listerial antigen, SOD, is immunologically uncharacterized, the naturally secreted protein of L. monocytogenes, p60, is known to be highly immunogenic. Our data emphasize the high vaccine potential of r-Salmonella constructs secreting antigens of somatic or secreted origin. Moreover, they suggest that the HlyB/HlyD/TolC-based antigen delivery system with attenuated Salmonella spp. as the carrier is capable of potentiating the immune response against foreign proteins independent from their immunogenicity in and display by the natural host.  相似文献   
30.
Reticuloendothelial system (RES) Fc receptor-mediated immune clearance was measured in 18 patients with systemic lupus erythematosus (SLE). Only two patients, with major disease activity, had a prolonged T 1/2 of the blood disappearance curve of injected IgG coated red cells in comparison to 22 healthy controls. Circulating immune complexes (CIC) were studied with three methods: PEG precipitation, C1q-ELISA and the indirect granulocyte phagocytosis test (IGFT). The T 1/2 of the blood disappearance curve related significantly to the IGFT (r = 0.55, P less than 0.05) and not to the PEG and C1q-ELISA test. Although HLA-DR3 phenotype frequency was significantly increased in our SLE population (P less than 0.05), it was not related to Fc receptor function. Similarly, HLA-DR2 phenotype was not related to RES Fc receptor function. These data do not support the concept that a genetic HLA linked defect in reticuloendothelial Fc receptor function is a primary cause of SLE, predisposing the inflicted individual to immune complex deposition. However, Fc receptor-mediated immune clearance seems to be related to disease activity itself and to levels of CIC.  相似文献   
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