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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.
Seminal vesicle cells of neonatally castrated adult mice show poor response to androgen, compared to those of mice castrated at adulthood; effects of pretreatment with androgen or estrogen at adulthood on androgen-induced proliferation of the seminal vesicle cells were examined in neonatally castrated mice. Male mice castrated at day 0 after birth were pretreated with daily injections of testosterone propionate (TP, 100 micrograms/mouse), 17 beta-estradiol (E2, 5 micrograms/mouse) or vehicle for 20 days starting from day 60; daily TP injections (100 micrograms/mouse) for 30 days were started again from day 110 in all the pretreated mice to examine androgen-induced proliferation by incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles. Both TP and E2 pretreatments significantly increased the seminal vesicle weight found before TP treatment. However, androgen-induced proliferation of the seminal vesicle found in neonatally castrated mice (poor response; long duration with a low peak on day 3) was changed at least in part to that found in mice castrated at adulthood (good response; short duration with a high peak on day 3) only following the TP pretreatment but not at all following the E2 pretreatment. The E2 pretreatment induced poor androgen-induced proliferation with a low peak on day 7.  相似文献   
13.
14.
Although many estimations have been made electronically of mammalian sperm volume, detailed investigations have not been reported for avian spermatozoa with an electronic counter. In the present study, sizing of spermatozoa of fowls and Muscovy and Pekin drakes was examined using a Coulter counter (model ZB). In our preliminary work on fowl sperm volumes, we found mono- or di-morphic distribution displays that were modified depending on the combination of amplification (AMP) and aperture current (APC). Therefore, methodology to estimate the fowl and drake sperm volume was examined. Dilution of semen had no effect on the dimorphic distribution pattern of the sperm volume. Density-gradient centrifugation did not separate two kind of particles in the semen in either continuous or discontinuous Percoll gradients; therefore, we varied settings of AMP and APC, and found that the most suitable settings for measuring sperm volumes of these birds are 1 for AMP and 8 for APC. With these settings, mean volumes of spermatozoa were 5.1 μm3 for fowls, 5.7 μm3 for Muscovy drakes, and 5.6 μm3 for Pekin drakes.  相似文献   
15.
A rat hepatocellular carcinoma, IQ7, induced by 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) gave two transformants of NIH 3T3 cells on DNA mediated gene transfer. One of these transformants was examined further and secondary and tertiary transformants were obtained. The secondary transformant was tumorigenic in nude mice. The activated oncogene in this primary transformant was identified as rat c-raf by Southern blot analysis.  相似文献   
16.
Studies were made on determination of the amount of water in rat skin by 1H NMR spectroscopy. The NMR spectrum obtained depended on how the skin was packed into the NMR tube. Consistent results were obtained by packing the skin into a specially designed NMR cell. By this technique the amount of water in the skin could be measured accurately, and results were comparable with those obtained by differential scanning calorimetry. The water content of the skin of rats was consistently about 20% more in females than in males.  相似文献   
17.
It is now known that nonphysiological cobalamin analogs exist in the gastrointestinal tract, but their metabolic behavior is unclear. In this study, [57Co]cobinamide was used to study its affinity to hog intrinsic factor-cobalamin (IF-Cbl) receptor which has no species specificity against human IF-Cbl receptor, and its relation to human saliva R binder. Cobinamide was prepared from [57Co]cyanocobalamin and separated by paper chromatography. Human IF-Cbl complex was bound to IF-Cbl receptor but free cyanocobalamin was not. Although R binder-cobinamide was not bound to the IF-Cbl receptor, free cobinamide was bound to the IF-Cbl receptor to a significant extent (about one-half of IF-cyanocobalamin binding to the IF-Cbl receptor). We then investigated the binding of cobinamide to R binder and trypsin-treated R binder. Association constant of cobinamide binding to the IF-Cbl receptor was 1.0 X 10(9) M-1 which was much lower than that of cobinamide binding to trypsin-treated R binder and to untreated R binder. Further study indicated that cobinamide binding to the IF-Cbl receptor was blocked by the addition of R binder and also by trypsin-treated R binder. We conclude that one of the roles of R binder is to prevent binding of free cobalamin analogs to the IF-Cbl receptor in the gut.  相似文献   
18.
Serum from normal human subjects contained variable amounts of catalase activity, which was inhibitable by heat, azide, trichloroacetic acid (TCA), or aminotriazole treatment. Serum also decreased hydrogen peroxide (H2O2) concentrations in vitro and H2O2-mediated injury to cultured endothelial cells. By comparison, heat-, azide-, TCA-, or aminotriazole-treated serum neither decreased H2O2 concentrations in vitro nor reduced H2O2-mediated damage to endothelial cells. We conclude that serum catalase activity can alter H2O2-dependent reactions. We speculate that variations in serum catalase activity may alter individual susceptibility to oxidant-mediated vascular disease or be a factor when added to test systems in vitro.  相似文献   
19.
H Kosaka  N Terada  Y Ito  M Uozumi 《Life sciences》1990,46(17):1249-1254
The effect of ascorbic acid deficiency on the urinary excretion of nitrate was investigated using a mutant strain of rats (osteogenic disorder syndrome rats; ODS rats) unable to synthesize ascorbic acid. The amount of urinary nitrate excreted by ODS rats with or without ascorbic acid supplementation were measured before and after the intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS). Urinary nitrate excretion increased markedly after LPS injection. Urinary nitrate excretion by ODS rats not supplied with ascorbic acid was significantly less than that of those supplied with ascorbic acid both before and after LPS injection. These results show that ascorbic acid enhances both LPS-stimulated and constitutive nitrate production in vivo.  相似文献   
20.
To determine if newly synthesized protein is imperative for the resumption of meiosis in bovine follicular oocytes collected from small antral follicles, cumulus-enclosed and denuded oocytes were cultured in TCM-199 both with and without various concentrations of the protein synthesis inhibitor, cycloheximide. After 11 h of culture in inhibitor-free medium, all oocytes had undergone germinal vesicle breakdown (GVBD). However, when concentrations of more than 1.0 mug/ml cycloheximide were added to the medium, the meiotic resumption of bovine oocytes was completely blocked. This inhibitory effect of cycloheximide was fully reversible after removal of the inhibitor from maturation media. Germinal vesicle breakdown following removal of cycloheximide occurred twice as fast as in the control medium. Nevertheless, when oocytes were arrested at the germinal vesicle (GV) stage by cycloheximide, a significantly higher proportion of chromatin condensation (40 to 57%) was observed in denuded oocytes than in cumulus-enclosed oocytes (11 to 22%). Thus the cycloheximide treatment could not prevent the chromatin condensation in only denuded oocytes. We conclude that protein synthesis is a prerequisite for GVBD in bovine follicular oocytes and that cumulus cells are responsible for the complementary regulation of the chromatin condensation at the GV stage, regardless of protein synthesis in the oocytes.  相似文献   
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