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241.
242.
A pure bacterial culture utilizing chromates and bichromates as oxygen donors during growth on organic substances in anaerobic conditions was isolated from active ooze of sewage and industrial wastes containing a weak solution of chromates. A medium for growth of the bacterium was selected, and its morphological and cultural properties were studied. Chromates and bichromates are reduced only in anaerobic conditions by the bacterium or active ooze containing it, the hexavalent chromium becoming trivalent. The culture does not belong to any known species and has been therefore classed as Pseudomonas dechromaticans.  相似文献   
243.
244.
The activity of the renin-angiotensin system was studied in experiments on rats under conditions of the inhibited prostaglandin synthesis. It was found that the injection of indometacin in non-hypertensive doses was accompanied by a substantial lowering of the plasma renin activity and of the secretory function of the juxtaglomerular apparatus of the kidneys. The amount of lipid granules increased in the interstitial cells simultaneously, this reflecting the inhibition of prostaglandin synthesis in the medulla of the kidneys. The results of these experiments permit the assumption to be made that the renin synthesis in the juxtaglomerular apparatus was connected with the synthesis of renal prostaglanins.  相似文献   
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246.
Urea cycle disorders and other hyperammonemic syndromes should be considered in the differential diagnosis in newborns with a history of severe vomiting, lethargy, and seizures, and in infants with feeding problems, episodic vomiting, and altered consciousness. Although the acute neonatal forms of urea cycle disorders are almost always lethal, several of the subacute forms of hyperammonemic syndromes respond favorably to early treatment.  相似文献   
247.
An experimental study of the temperature dependence of the binary diffusion coefficients (BDCs) was conducted for five binary mixtures of gases: $\mathrm{H}_{2}{-}\mathrm{N}_{2}, \mathrm{H}_{2}{-}\mathrm{CO}, \mathrm{H}_{2}{-}\mathrm{CH}_{4}, \mathrm{H}_{2}{-}\mathrm{C}_{2}\mathrm{H}_{6}$ , and $\mathrm{H}_{2}{-}\mathrm{C}_{3}\mathrm{H}_{8}$ . Measurements were carried out with the use of a steady-flow method in the temperature range from 250 K to 900 K and the pressure range from 0.1 MPa to 15 MPa. The determination of the BDCs is based on analysis of the volume fraction of the diffusing gas in the gas flow. The experimental data were compared with the results of calculations by the proposed formula evaluated within the framework of the elementary kinetic theory. The obtained results exhibit considerably good agreement with the experimental data within the experimental error. The results of investigations of the temperature dependence of the BDCs show that this dependence can be fitted with a power law only at atmospheric pressure.  相似文献   
248.
Since the year 1987 to 1996 all kinds of thyroid surgeries were performed at the ENT Department. Altogether 604 patients underwent 655 surgeries. Total lobectomy or total thyroidectomy represented the most common procedures. Due to a gentle surgical technique, which we call "preparation", good results were achieved in the morbidity of laryngeal recurrent nerve (permanent palsy in 0.6%), and in perioperative or postoperative bleeding (0.3% of wound revisions, 0.5% of blood transfusions). Postoperative hypoparythyroidism was found in 4.7% patients. There is no correlation between postoperative hoarseness and laryngeal recurrent nerve palsy. Laryngeal endoscopy immediately after surgery is the most valuable diagnostic procedure.  相似文献   
249.
A 159 residue, N-terminal fragment of the human C1s complement component, C1s alpha(159), was expressed in the baculovirus, insect cell system. The protein was abundantly produced 3 days after infection, reaching levels as high as 40 microg/ml in cell culture media. It had a molecular weight of 18,100 (+/-4.9) Da by laser desorption mass spectrometry, close to the theoretical value of 18,111 Da, confirmed by sequencing. Sedimentation equilibrium and gel filtration column chromatography showed that C1s alpha(159) was a monomer in the presence of EDTA, and a dimer in the presence of Ca2+. The C1s alpha(159)2 dimer had a sedimentation coefficient of 3.1 S. When the C1s alpha(159)2 was mixed with Clq, there was little or no interaction. Likewise, unactivated C1r2 dimer had a sedimentation coefficient of 6.8 S, and when mixed with C1q little or no interaction was observed. When C1s alpha(159)2 was mixed with the 6.8 S C1r2 in Ca2+, a 7.5 S complex was formed, presumably the C1s alpha(159) x C1r x C1r x C1s alpha(159) tetramer. When C1q, which migrated at 10.1 S was mixed with C1s alpha(159)2 and C1r2 in the presence of Ca2+, a C1-like complex, but containing C1s alpha(159) instead of C1s, was formed which migrated at 14.0 S. This C1-like molecule remained unactivated unless challenged with an ovalbumin-antiovalbumin immune complex. In the presence of immune complex, the C1r became activated. This suggested that the presence of the 159 amino acid C1s alpha domain, which held the C1r to the C1q, was sufficient to permit activation by an immune complex, even though the catalytic domains of C1s were not present.  相似文献   
250.
We have conducted a prospective study aimed to analyse contraceptive use among women seeking for legal abortion in the State University Hospital "Ma?chin dom"--Sofia. Our date demonstrate that the patients were well informed about the existing contraceptive methods. On the contrary the percentage of women-using contraception and especially those, using highly effective ones is relatively low. The patients claim the possible side effects of the high effective contraception as a reason against use.  相似文献   
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