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991.
Y Oh ML Proctor YH Fan LK Su WK Hong KM Fong YS Sekido AF Gazdar JD Minna L Mao 《Canadian Metallurgical Quarterly》1998,17(9):1141-1148
Adrenocortical autoantibodies (ACA), present in 60-80% of patients with idiopathic Addison's disease, are conventionally detected by indirect immunofluorescence (IIF) on frozen sections of adrenal glands. The large-scale use of IIF is limited in part by the need for a fluorescence microscope and the fact that histological sections cannot be stored for long periods of time. To circumvent these restrictions we developed a novel peroxidase-labelled protein A (PLPA) technique for the detection of ACA in patients with Addison's disease and compared the results with those obtained with the classical IIF assay. We studied serum samples from 90 healthy control subjects and 22 patients with Addison's disease, who had been clinically classified into two groups: idiopathic (N = 13) and granulomatous (N = 9). ACA-PLPA were detected in 10/22 (45%) patients: 9/13 (69%) with the idiopathic form and 1/9 (11%) with the granulomatous form, whereas ACA-IIF were detected in 11/22 patients (50%): 10/13 (77%) with the idiopathic form and 1/9 (11%) with the granulomatous form. Twelve of the 13 idiopathic addisonians (92%) were positive for either ACA-PLPA or ACA-IIF, but only 7 were positive by both methods. In contrast, none of 90 healthy subjects was found to be positive for ACA. Thus, our study shows that the PLPA-based technique is useful, has technical advantages over the IIF method (by not requiring the use of a fluorescence microscope and by permitting section storage for long periods of time). However, since it is only 60% concordant with the ACA-IIF method, it should be considered complementary instead of an alternative method to IIF for the detection of ACA in human sera. 相似文献
992.
KM Pawlik 《Canadian Metallurgical Quarterly》1998,37(9):418-421
This is a report of 3 Chinese children with intestinal lymphangiectasia in Malaysia. Two children responded to a low fat diet and medium-chain triglyceride supplement. The third child has recurrent chylous ascites. None of the children has recurrent infections despite low CD4+ cells and low levels of IgG and IgA. Intestinal lymphangiectasia is a rare congenital disorder of the mesenteric lymphatic that leads to the obstruction of the lymphatics of the intestine and protein losing enteropathy. Restriction of dietary fat intake will usually result in remission. Recurrent chylous ascites is a problem and management can be difficult. 相似文献
993.
Selective serotonin reuptake inhibitors are useful in the treatment of posttraumatic stress disorder (PTSD), but have a number of side-effects which limit their acceptability. A newer serotonergic compound, nefazodone, has a different side-effect profile, thus making it a potentially promising compound to study. Seventeen private practice patients with PTSD were treated with nefazodone up to 600 mg/day for a maximum total treatment period of 12 weeks. All subjects were civilians, and were monitored for efficacy and side-effects at weeks 1, 2, 4, 6, 8 and 12. Nefazodone was associated with statistically significant improvement in mean scores on all six rating scales used to assess change from baseline in PTSD symptoms. Additionally, statistically significant improvement from baseline were seen for the intrusive, avoidant/numbing, and hyperarousal clusters on a global PTSD scale. Early improvements in nightmares and general sleep disturbance were observed. Overall, there was a 43% response rate at endpoint, or 60% in treatment completers, by observer rating. Side-effects (assessed on the Medication Effects Scale) were generally benign. Nefazodone was associated with clinical improvement in this population, and now needs to be studied in double-blind, placebo controlled, protocols. 相似文献
994.
995.
K Ishikawa KM Matera H Zhou H Fujii M Sato T Yoshimura M Ikeda-Saito T Yoshida 《Canadian Metallurgical Quarterly》1998,273(8):4317-4322
A truncated, soluble, and enzymatically active form of human heme oxygenase-2 (DeltaHHO2) was expressed in Escherichia coli. To identify the axial heme ligand of HO-2, His-45 to Ala (DeltaH45A) and His-152 to Ala (DeltaH152A) mutants have been prepared using this expression system. DeltaH45A could form a 1:1 complex with hemin but was completely devoid of the heme degradation activity. A 5-coordinate-type ferrous NO EPR spectrum was observed for the heme-DeltaH45A complex. The DeltaH152A mutant was expressed as an inclusion body and was recovered from the lysis pellet by dissolution in urea followed by dialysis. The solubilized fraction obtained, however, was composed of a mixture of a functional enzyme and an inactive fraction. The inactive fraction was removed by Sephadex G-75 column chromatography since it eluted out of the column at the void volume. The gel filtration-purified DeltaH152A exhibited spectroscopic and enzymatic properties identical to those of wild-type. We conclude, in contrast to the previous reports (McCoubrey and Maines (1993) Arch. Biochem. Biophys. 302, 402-408; McCoubrey, W. K., Jr., Huang, T. J., and Maines, M. (1997) J. Biol. Chem. 272, 12568-12574), that His-45, but not His-152, in heme oxygenase isoform-2 is the proximal ligand of the heme and is essential for the heme degradation activity of the enzyme. His-152 appears to play a structural role in stabilization of the heme oxygenase protein. 相似文献
996.
Neonatal freeze lesions to the cortical plate result in focal malformations of the cerebral cortex that resemble four-layered microgyria. These malformations have been associated with local and distant changes in neuronal architecture, and have been implicated in the neocortical epileptiform discharges that can spread up to 4 mm away from the malformation itself. In an effort to assess potential changes in the development of one population of inhibitory interneurons in this malformation, we measured the density of parvalbumin-immunoreactive (ParvIR) neurons in microgyric and control cerebral cortex on postnatal days 13, 15, 21 and 64. In comparison to controls, microgyric animals exhibited a transient decrease in the expression of parvalbumin immunoreactivity in supragranular neurons, both within the malformation itself and in normal six-layered cortex up to 2 mm adjacent to it. This difference disappeared by P21. In addition, there was a permanent diminution of the density of ParvIR neurons in infragranular layers both within and immediately adjacent to the microgyrus. These results indicate that early injury to the cortical plate gives rise to both focal and more widespread changes in cortical architecture. 相似文献
997.
KM Hanion-Lundberg RS Kirby S Gandhi FF Broekhuizen 《Canadian Metallurgical Quarterly》1997,176(6):1149-54; discussion 1154-6
OBJECTIVE: This study aims to establish normal values for nucleated red blood cells in term singletons and factors associated with their elevation. STUDY DESIGN: Cord blood was prospectively collected from term singleton gestations from Feb. 1 to July 31, 1995. Umbilical vein white blood cells and nucleated red blood cells were counted and umbilical arterial pH was determined. Medical records provided maternal and neonatal information. RESULTS: Cord blood from 1112 cases was obtained and evaluated for nucleated red blood cells per 100 white blood cells. Nine outliers were censored (nucleated red blood cells per 100 white blood cells = 126 to 830); five cases were excluded because of missing data. The mean value of nucleated red blood cells per 100 white blood cells was 8.55, the SD was 10.27, and the range was 0 to 89. The value did not very by maternal tobacco or drug use, anemia, fetal presentation, or mode of delivery. Both maternal diabetes and meconium were associated with elevated values, p < 0.01. Apgar scores and cord pHs showed trends toward inverse proportionality to the number of nucleated red blood cells per 100 white blood cells. CONCLUSION: The mean number of nucleated red blood cells per 100 white blood cells was 8.55, with a wide range and SD. Elevated values may be associated with markers of intrauterine hypoxia such as meconium, lower Apgar scores, and lower pH values. 相似文献
998.
999.
Rex Hartson 《Behaviour & Information Technology》2003,22(5):315-338
In reaction to Norman's (1999) essay on misuse of the term affordance in human-computer interaction literature, this article is a concept paper affirming the importance of this powerful concept, reinforcing Norman's distinctions of terminology, and expanding on the usefulness of the concepts in terms of their application to interaction design and evaluation. We define and use four complementary types of affordance in the context of interaction design and evaluation: cognitive affordance, physical affordance, sensory affordance, and functional affordance. The terms cognitive affordance (Norman's perceived affordance) and physical affordance (Norman's real affordance) refer to parallel and equally important usability concepts for interaction design, to which sensory affordance plays a supporting role. We argue that the concept of physical affordance carries a mandatory component of utility or purposeful action (functional affordance). Finally, we provide guidelines to help designers think about how these four kinds of affordance work together naturally in contextualized HCI design or evaluation. 相似文献
1000.
RJ Bergeron WR Weimar G Luchetta RR Streiff J Wiegand J Perrin KM Schreier C Porter GW Yao H Dimova 《Canadian Metallurgical Quarterly》1995,23(10):1117-1125
The pharmacokinetics and metabolism of N1,N11-diethylnorspermine (DENSPM) is described. When administered to dogs as an intravenous bolus, DENSPM was shown to have a plasma half-life of 72.8 +/- 11.8 min, with an early distribution phase half-life of approximately 4 min and an apparent volume of distribution of 0.216 +/- 0.032 liter/kg. The renal clearance half-life was 59.7 +/- 7.6 min, with 48.8 +/- 12.5% of the drug recovered in the urine between 0-4 hr unchanged. In three other experiments, the drug was administered to dogs by constant rate intravenous infusion over periods ranging from 10 min to 2 hr. Analysis of plasma concentration-time data and urinary excretion data yielded pharmacokinetic parameters in general agreement with the intravenous bolus experiments. DENSPM metabolites were identified in both beagle dog and mouse tissues. Tissues were sampled from a single beagle 24 hr posttreatment, and rodent samples were examined at 12, 24, 48, and 96 hr posttreatment. Both the concentration of DENSPM and the metabolic profile were shown to vary in the lung, liver, spleen, and kidney. Although all the tissues examined contained DENSPM and its metabolites, the liver and kidney had the highest level of metabolites that included N1-ethylnorspermine, N1-ethylnorspermidine, N1-ethyl-1,3-diaminopropane, and norspermidine. These data suggest that DENSPM is metabolized by N-deethylation and step-wise removal of aminopropyl equivalents by spermine/spermidine N1-acetyltransferase/polyamine oxidase, a metabolic pathway unique to the polyamines. 相似文献