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971.
A family is described in which the mother and 2 of the 5 children had Felty's syndrome, a pattern of inheritance suggesting a dominant defect and one which has not previously been reported. The family is also of interest in that the other sib had rheumatoid arthritis. 相似文献
972.
Determination of magnesium and potassium binding constants to phosphoenolpyruvate, 2- and 3-phosphoglycerate and a number of other anions 总被引:2,自引:0,他引:2
KL Manchester 《Canadian Metallurgical Quarterly》1980,630(2):225-231
The stability constants for the binding of magnesium ions to phosphoenolpyruvate, 2- and 3-phosphoglycerates, 2,3-diphosphoglycerate, Pi, glucose 6-phosphate, isocitrate, glutamate and NAD have been determined spectrophotometrically in the presence of 8-hydroxyquinoline at 25 and 37 degrees C. Estimates of potassium binding constants have also been calculated for phosphoenolpyruvate and 2- and 3-phosphoglycerate and compared with previously published values. 相似文献
973.
Dong H. Nguyen 《Nuclear Engineering and Design》1979,53(2):207-215
The optimum number of fuel pins in a test vehicle to achieve prototypic thermal-hydraulic conditions at the onset of pin failure has been determined. The power history considered was a prompt burst superposed on a low steady state power level. Slower transients without pre-clad-failure boiling did not change the conclusions presented in this paper. The analysis used the computer program COBRA-IV-I, with a unique capability of large wire-wrapped asymmetric rod bundles up to 217 pins. The results indicate that a 61-pin test scale is dersirable to achieve thermal-hydraulic conditions for prototypic testing, with 37 pins probably an acceptable minimum. 相似文献
974.
KM Itani SS Rothenberg ML Brandt JM Burch KL Mattox FJ Harberg WJ Pokorny 《Canadian Metallurgical Quarterly》1993,28(5):677-680
During the 6-year period from 1983 to 1989, 109 children aged 3 to 18 years (mean, 16) with suspected peripheral vascular injuries underwent 113 emergency center arteriograms (ECA) performed by hand injection of contrast material using a single roentgenographic film. The most common indication for ECA was the proximity of the injury in 93 (82.3%) of the cases as penetrating injury accounted for 106 (94%) of the cases. There were 89 true-negative, 14 true-positive, 1 false-negative, and no false-positive arteriograms. The remaining 9 arteriograms were either equivocal or technically inadequate. The sensitivity, specificity, and diagnostic accuracy of this procedure were 98.9%, 100%, and 91.2%, respectively. Operative intervention was required for 9 (64.2%) injuries detected by emergency arteriography. The remaining 5 injuries were considered minor and were observed with no complications during a period of 21 months. Sixty-eight children (76.4%) with negative ECA were followed for a mean of 12 months with no vascular complications or growth abnormalities noted. ECA is a rapid, accurate, and cost-effective technique. It is of particular value in detecting the presence of occult arterial injuries that might have deleterious effects in the growing child. 相似文献
975.
SC Bosshardt JW McCall SU Coleman KL Jones TA Petit TR Klei 《Canadian Metallurgical Quarterly》1993,79(5):775-777
The ability of oral tetracycline to inhibit the development of third-stage infective larvae (L3) of Brugia pahangi to adult worms in jirds was studied using 2 experimental protocols. Jirds treated with 1.4% tetracycline in drinking water for a period beginning 30 days before inoculation of L3 until 30 days post-inoculation (DPI) had 97% reduction in adult worm recovery compared to untreated controls. Jirds that received 1.2% tetracycline in drinking water beginning 1 day before until either 12 or 26 DPI had adult worm recoveries of 11% and < 1%, respectively. Untreated jirds and those given tetracycline beginning at or later than 13 DPI had similar adult worm recovery (27-29%). Prepatent periods were prolonged, and circulating microfilariae were reduced in jirds given tetracycline from 27 to 54 DPI compared to controls. These data indicate that tetracycline administered to jirds in drinking water inhibits B. pahangi development from L3 to adult worms and suggest that this effect occurs during early larval development. Tetracycline administered to infected jirds prior to and continuing through the onset of patency can also affect development of microfilaremia. 相似文献
976.
Angiotensin converting enzyme (ACE) and leucine aminopeptidase (LAP) regulate fetally and maternally generated peptides in the placenta. In this study, ACE-like activity was found to be decreased and LAP-like activity increased with increasing days of gestation in rat placental tissues forming the fetal:maternal interface. Membrane-associated ACE-like and LAP-like activities in the placenta of smokers were also found to be significantly higher than their respective activities in placenta of nonsmokers. Our collective findings suggest that gestational and environmentally-induced changes in placental peptidase activities may account for variable peptide hormone and/or therapeutic peptide metabolism in the placenta. 相似文献
977.
Previous electrophysiological studies in pigeons have shown that the vestibulocerebellum can be divided into two parasagittal zones based on responses to optic flow stimuli. The medial zone responds best to optic flow resulting from self-translation, whereas the lateral zone responds best to optic flow resulting from self-rotation. This information arrives from the retina via a projection from the accessory optic system to the medial column of the inferior olive. In this study we investigated inferior olive projections to translational and rotational zones of the vestibulocerebellum using the retrograde tracer cholera toxin subunit B. Extracellular recordings of Purkinje cell activity (complex spikes) in response to large-field visual stimuli were used to identify the injection sites. We found a distinct segregation of inferior olive cells projecting to translational and rotational zones of the vestibulocerebellum. Translation zone injections resulted in retrogradely labeled cells in the ventrolateral area of the medial column, whereas rotation zone injections resulted in retrogradely labeled cells in the dorsomedial region of the medial column. Motion of any object through space, including self-motion of organisms, can be described with reference to translation and rotation in three-dimensional space. Our results show that, in pigeons, the brainstem visual systems responsible for detecting optic flow are segregated into channels responsible for the analysis of translational and rotational optic flow in the inferior olive, which is only two synapses from the retina. 相似文献
978.
TJ Doering KL Resch B Steuernagel J Brix B Schneider GC Fischer 《Canadian Metallurgical Quarterly》1998,77(6):490-493
Zinc levels in seminal plasma were measured. The study was done on 122, random selected males from infertile couples. The atomic absorption spectrophotometer was used. Sperm density of ejaculate was also determined. These parameters were compared in subgroups: normospermic and oligospermic and in classes of variable oligospermic severity. Semen serum zinc levels in normospermic men was significantly increased as compared to oligospermic men. There were no significant differences in zinc levels between the different classes of oligospermia. 相似文献
979.
V Haroutunian DP Perl DP Purohit D Marin K Khan M Lantz KL Davis RC Mohs 《Canadian Metallurgical Quarterly》1998,55(9):1185-1191
BACKGROUND: Identification of the neuropathological lesions that are most closely associated with the earliest symptoms of Alzheimer disease (AD) is crucial to the understanding of the disease process and the development of treatment strategies to affect its progress. Do the classical neuropathological lesions of AD precede, follow, or occur in synchrony with the earliest signs of cognitive deterioration? DESIGN AND OUTCOME MEASURES: We examined the extent of neuritic plaque (NP) formation in 5 neocortical regions and the hippocampus, entorhinal cortex, and amygdala in 66 elderly subjects with no dementia, questionable dementia, or mild dementia as assessed using the Clinical Dementia Rating Scale (CDR). SETTING AND PATIENTS: Postmortem study of nursing home residents. RESULTS: Even questionable dementia (CDR, 0.5) was associated with a significant (P = .04) increase in neocortical NP density. The density of NPs increased further with increasing dementia severity in all brain regions examined. However, subjects with questionable dementia or definite but mild dementia did not differ significantly from each other. Density of NPs was nearly maximal in subjects with moderate dementia (CDR = 2.0), suggesting that other neuropathological changes may be responsible for cognitive deficits beyond this level. Dementia severity correlated significantly with the density of NPs in all brain regions examined (r range, 0.47-0.56; P < .001), even when subjects with a CDR of 0 were excluded. CONCLUSIONS: These findings are consistent with the hypothesis that NPs are among the earliest neuropathological lesions in AD. Even very mild or questionable dementia is associated with increased density of neocortical NPs that do not distinguish between clinically questionable vs definite dementia. 相似文献
980.
Recently, it has been shown at both the cellular and behavioral levels that ethanol has effects on the N-methyl-D-aspartate (NMDA) and gamma-aminobutyric acid (GABA)a receptor systems, leading to the possibility that the reinforcing effects of ethanol may be, at least partially, mediated via these receptor ionophores. In this study, a multiple schedule of ethanol and saccharin self-administration was used to study that possibility. Adult male Long-Evans rats were trained during 1-hr sessions to press on two different levers for 10% (w/v) ethanol and 0.1% (w/v) saccharin solutions, under an alternating 5-min, fixed-ratio-4 schedule of liquid availability. After training, tests were conducted with ethanol, NMDA antagonists and GABA agonists given before six consecutive sessions. Pretreatment with ethanol selectively decreased ethanol self-administration without altering saccharin self-administration. The competitive NMDA antagonist CPPene (D-3-(2-carboxypiperazine-4-yl)-1-propenyl-1-phosphonic acid [SDZ EAA 494]) and the noncompetitive NMDA antagonist phencyclidine decreased both ethanol and saccharin self-administration. The GABA agonists pentobarbital and diazepam also failed to reduce ethanol self-administration, relative to saccharin. Although these results do not support the hypothesis that antagonism of the NMDA receptor system or activation of the GABA receptor system can selectively modify ethanol-reinforced responding, they identify important issues for designing the best strategies to be used to assess selective drug effects on ethanol self-administration. 相似文献