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11.
A heat-treated factor VIII (F VIII) concentrate (Haemate P) has been administered to patients with various types of von Willebrand's disease (vWD). The 4 activities of F VIII/vWF as well as change in the multimeric structure of vWF were then studied. In 4 patients with type I vWF who were given a Ristocetin cofactor (Rcof) dose of 42-78 U/kg, there was a clear reduction of the bleeding time and an increase of F VIII: C, F VIII: Ag, Rcof and vWF: Ag for several hours. The recovery of Rcof. after 1 h was 50-75%. Although the multimeric composition of vWF in these patients was similar to that of normal plasma, the density of each multimer band was very low. After infusion, however, the density of all multimer bands increased for several hours, to decrease again after 24 h. In 4 patients with type II A vWD who received a dose of Rcof of 55-76 U/kg, the 4 activities of F VIII/vWF increased similarly as was the case in type I. All patients had only 3-4 smaller multimer bands. New larger and intermediate multimers appeared for several hours after infusion of the preparation. Two patients with type III vWD who received doses of Rcof of 52 and 65 U/kg showed also a similar increase in the 4 activities of F VIII/vWF after infusion. All the multimers lacking in these patients appeared for several hours after infusion.  相似文献   
12.
The plasma levels of fibronectin (Fn) have been measured in normal subjects and in patients with thyroid diseases. The mean plasma Fn levels in 62 normal adults was 32.0 +/- 6.0 mg/dl, whereas it was elevated to 62.6 +/- 16.1 mg/dl (mean +/- SD) in 25 patients with hyperthyroidism and decreased to 19.2 +/- 8.0 mg/dl in 9 patients with hypothyroidism. The 9 patients with simple goiter have normal values of 29.1 +/- 8.0 mg/dl. With the administration of anti-thyroid drugs, plasma Fn levels normalized, with a time lag, in parallel with normalization of the thyroid function. Positive correlation was obtained between Fn levels and serum levels of triiodothyronine (T3) and thyroxine (T4). The present findings indicate that measurement of plasma Fn both in the basal state and during treatment provides evidence of altered Fn metabolism in thyroid diseases and serves to follow up the effect of treatment.  相似文献   
13.
Crude and purified xanthine dehydrogenase preparations from rat liver were examined for the existence of a naturally occurring inactive form. Reduction of the purified enzyme by xanthine under anaerobic conditions proceeded in two phases. The enzyme was inactivated by cyanide, which caused the release of a sulfur atom from the molybdenum center as thiocyanate. The amount of thiocyanate released was almost in parallel with the initial specific activity. The active and inactive enzymes could be resolved by affinity chromatography on Sepharose 4B/folate gel. These results provided evidence that the purified enzyme preparation from rat liver contained an inactive form. A method for the determination of the active and inactive enzymes in crude enzyme preparations from rat liver was devised based on the fact that only active enzyme could react with [14C]allopurinol and both active and inactive enzymes could be immunoprecipitated quantitatively by excess specific antibody to xanthine dehydrogenase. The amount of [14C]alloxanthine (derived from [14C]allopurinol) bound to the active sulfo enzyme in crude rat liver extracts was about 0.5 mol/mol of FAD. As this content is closely similar to that in the purified enzyme, these results suggest the existence of an inactive desulfo form in vivo.  相似文献   
14.
An altered cytochrome P-450 (SG1 P-450) was partially purified from Saccharomyces cerevisiae mutant SG1 which is defective in lanosterol 14 alpha-demethylation. Oxidized SG1 P-450 showed a Soret peak at 422 nm and the alpha peak was lower than the beta peak. This spectrum was considerably different from those of known low-spin P-450s, indicating a unique ligand structure of SG1 P-450. The absorption spectrum of ferric SG1 P-450 was superimposable on that of the imidazole complex of ferric P-450, suggesting the presence of a nitrogenous ligand such as histidine of the apoprotein at the 6th coordination position. SG1 P-450 was immunochemically indistinguishable from cytochrome P-450 of S. cerevisiae catalyzing lanosterol 14 alpha-demethylation (P-45014DM) but had no lanosterol 14 alpha-demethylase activity.  相似文献   
15.
Fluctuations of the population abundance of the rose bitterling,Rhodeus ocellatus (Kner) in a small pond, Shimizu-ike (700 m2), Osaka Prefecture, Japan, were estimated by the Petersen method from 1973 to 1977. The number of fish fluctuated between 12,600 and 46,700 during that period. In 1974, a large reproductive peak in May contributed mainly by 2- and 3-year-old spawners and a small peak in late July contributed by 1–2-year-old fish were observed. Average number of eggs laid in a bivalve,Anodonta woodiana Lea, in each month was estimated with field experiments from March to November, 1974. In total, 93,400 eggs were laid during the first reproductive peak, and 13,100 eggs during the second reproductive peak. The mortality of eggs and larvae incubated in the bivalve was less than 30%, and approximately 70 % of the larvae that had swum out from the host died in the following six months. Thus, it is estimated that approximately 20% of the eggs laid in the bivalves can survive and grow up to reach the first maturity. The high survival rate ofR. ocellatus among cyprinid fishes might be due to the fact that the eggs and larvae are protected from predation by being embedded in a bivalve, and to the fact that the larvae at the earliest free swimming stage have a good opportunity of surviving because they are much larger in size and more developed morphologically than those of other cyprinid fishes.  相似文献   
16.
17.
TPA alone did not induce the production of IL 2 in human tonsillar lymphocytes but enhanced the PHA-induced IL 2 production by seven-fold. That the effect of TPA was due to an increase in IL 2 mRNA was demonstrated by examining the amount of IL 2 mRNA translatable in Xenopus laevis oocytes, and by Northern blotting analysis using IL 2 cDNA as a probe. In these ways, it was shown that TPA alone did not induce any significant IL 2 mRNA synthesis, but when added together with PHA it increased the level of IL 2 mRNA by at least 10-fold, as compared with that induced by PHA alone.  相似文献   
18.
Isolation and characterization of a human interleukin 2 gene   总被引:1,自引:0,他引:1  
An interleukin 2 (IL-2) gene was isolated from a Charon 4A human gene library. Electron microscopic examination of 15 heteroduplexes formed between the genomic DNAs and the IL-2 cDNAs demonstrated that the size of the IL-2 gene is about 5.1 +/- 0.5 kb and that there are at least two introns in this gene. Nucleotide sequence of the 5' flanking region of the IL-2 gene showed a homology with that of the corresponding region of the human immune interferon gene.  相似文献   
19.
Vasodilatory and natriuretic effects of captopril were studied in the isolated hog kidney perfused with modified Krebs-Ringer solution. Renal arterial infusion of captopril caused increases in releases of renin, prostaglandins (PGE2, 6-keto-PGF1 alpha and PGF2 alpha) and kinin, and was accompanied by a decrease in the renal vascular resistance and an increase in urinary sodium excretion. Indomethacin administered with captopril diminished the saluretic effect of captopril and evoked an increase in kinin, but was associated with a marked decrease in prostaglandin and renin releases, while renal vascular resistance remained decreased. Indomethacin alone did not alter vascular resistance and kinin; however, renin and prostaglandin releases were decreased. Aprotinin administered with captopril showed a decrease in releases of prostaglandins, renin and kinin without any change in vascular resistance. These results suggest that increased release of kinin induced by captopril contributes to a reduction in renal vascular resistance. Increased prostaglandin release after captopril administration may be caused by an increase in kinin without direct involvement of captopril in prostaglandin synthesis. Renal prostaglandins may enhance sodium excretion and mediate renin secretion in captopril perfusion.  相似文献   
20.
Carrier-mediated transport of thiamine in baker's yeast   总被引:5,自引:0,他引:5  
  相似文献   
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