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991.
SG Massry R Stein J Garty AI Arieff JW Coburn AW Norman RM Friedler 《Canadian Metallurgical Quarterly》1976,9(6):467-474
Studies were carried out to investigate the role of 1,25(OH)2D3 in the skeletal resistance to the calcemic action of parathyroid hormone. The change in serum calcium after the intravenous infusion of 2 U of parathyroid extract (PTE)/kg body wt/hr for eight hours was evaluated in thyroparathyroidectomized (T-PTX) dogs before, and one, two and three days after, induction of uremia by bilateral ureteral ligation (11 dogs) or by bilateral nephrectomy (8 dogs). In another six nephrectomized and T-PTX dogs, 0.68 ug of 1, 25 (OH)2D3/day was given on the day of nephrectomy and for two days thereafter. Serum creatinine in each day of the study was not different among the three groups. The study also included the evaluation of the effect of sham operation (five dogs) and the administration of 1,25 (OH)2D3 to dogs with normal renal function (four dogs) on the calcemic response to PTE, as well as the reproducibility of such a response in the same animal. The results showed that 1) the calcemic response to PTE was markedly impaired after one day of bilateral ureteral ligation or nephrectomy, but the impairment was more severe after nephrectomy; 2) the calcemic response to PTE after two or three days of bilateral ureteral ligation was similar to that seen at one day after nephrectomy; 3) 1, 25 (OH)2D3 partially restored the calcemic response to PTE in the nephrectomized animals to levels similar to those seen after one day of bilateral ureteral ligation; 4) sham operation did not affect the response to PTE, and repeated infusion of PTE produced similar changes in the concentrations of serum calcium. The data indicate that (a) a deficiency of 1,25 (OH)2D3 is at least partly responsible for the skeletal resistance to the calcemic action of PTH in uremia; (b) uremia, per se, may also contribute to this phenomenon; and (c) the kidney after one day of complete bilateral ureteral ligation may still produce 1,25 (OH)2D3, but this ability is compromised after two days of ureteral obstruction. 相似文献
992.
The standard high volume sampler, multistage cascade impactor, and modified vertical elutriators were evaluated for total cotton dust sampling. The effects of changes in performance parameters is reported. Mass median dust diameter found in four textile operations for several cotton grades are reported. 相似文献
993.
RM Baddeley 《Canadian Metallurgical Quarterly》1976,63(10):801-806
The results of jejuno-ileostomy in 182 patients have been studied. The operative mortality was 1-1% and the overall mortality 6-6%, of which 3-3% was attributable to the effects of the small bowel bypass. Weight reduction usually ceased at about 18-24 months postoperatively, by which time the average fall was 36-3% of the mean original body weight. Males and younger patients achieved better than average results. The main side-effects were fatty infiltration of the liver, polyarthralgia, excessive diarrhoea and electrolyte upsets. 相似文献
994.
995.
Using HeLa TCRC-1, a cell line which is monophenotypic with respect to the Regan isoenzyme of alkaline phosphatase, we have examined the factors which influence its expression in relation to events of the cell cycle. DNA synthesis is not required for hormone induction of the Regan isoenzyme as in the presence of hydroxyurea, a specific inhibitor of DNA synthesis, we found induction to occur. Additionally, when partially synchronised cells were allowed to leave the S period prior to hormone treatment, and hydroxyurea was added to prevent cells from entering the next S period, hormone induction of the Regan isoenzyme was still observed. This indicates that initiation of expression of hormone-induced carcinoplacental alkaline phosphatase occur prior to the DNA synthetic phase of the cell cycle. We propose a hypothetical two-step mechanism of hormone induction to interpret the present findings in relation to previous results. 相似文献
996.
Naws about "cults" in the United States is clearly information by outsiders for outsiders and, although not uniformly negative, can best be described as "a stream of controversies" with little attention to the history or human side of the new, religions. 相似文献
997.
998.
999.
Sera from 30 of 303 (9.9%) unselected term newborn infants were deficient in their ability to opsonize heat-killed baker's yeasts, an incidence which is almost double that seen in adults. Genetic influence is important in some since the mothers of 10 infants with defective opsonization showed the same defect, but it was not related to the sex or race of the infant or to the atopic state of the parents. In others the defect could be due to a functional maturation delay of the complement system, but not to inhibitory factors in neonatal serum since correction of opsonization was achieved with subopsonizing amounts of normal sera. Significantly more infants had sera with high opsonizing capacity (greater than 80% yeasts phagocytosed) when compared with adults; perhaps antibody independent immune mechanisms like this are important in the newborn. This study shows that a common specific immunodeficiency which may predispose to severe infection or atopy can be identified at birth. 相似文献
1000.
In signal processing problems associated with estimation or pattern recognition in nondestructive evaluation (NDE), the degree of adaption can vary between wide limits, and is related to the availability or usability of a priori information. We will discuss several examples of NDE signal processing problems involving varying degrees of adaption, namely: (1) a completely nonadaptive approach to the extraction of low frequency properties of scatterers, (2) a semi-adaptive approach to the same problem, and (3) a completely adaptive approach to the classification of acoustical emission signals. 相似文献