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Chlorobium limicola forma thiosulfatophilum (ATCC 17092) was grown in a 1-liter continuously stirred tank reactor (800-ml liquid volume) at pH 6.8, 30°C, saturated light intensity, and a gas flow rate of 23.6 ml/min from a gas cylinder blend consisting of 3.9 mol% H2S, 9.2 mol% CO2, 86.4 mol% N2, and 0.5 mol% H2. This is the first demonstration of photoautotrophic growth of a Chlorobium sp. on a continuous inorganic gas feed. A significant potential exists for applying this photoautotrophic process to desulfurization and CO2 fixation of gases containing acidic components (H2S and CO2).  相似文献   
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The Tel Hashomer variant of human G6PD migrates as two prominent components during electrophoresis in several gel systems in which red cell G6PD from other males migrates predominantly as a single band. Since human males normally have but one X-chromosome, the extra band of this variant seemed an exception to earlier biochemical and genetic observations suggesting that human red cell G6PD is determined by a locus on the X chromosome. Results of the present studies indicate that the Tel Hashomer variant is unusually susceptible to the formation of a complex which has a higher molecular weight than normal G6PD and which represents the slow electrophoretic component. The conditions of formation and disruption of this complex in crude and purified Tel Hashomer preparations suggest that it results from the formation of disulfide bridges between molecules of Tel Hashomer G6PD.Supported by U.S. Public Health Service Research Grants AM-11065 and FR-5406 and Research Career Development Award 5 K3 AM 7992.  相似文献   
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1. Native DNA from Bacillus subtilis was fractionated by stepwise elution from methylated albumin, the transforming activity being confined to two out of four fractions. Partial separation of DNA active in transformation for the arginine marker from that showing activity for the histidine and tryptophan markers was achieved. 2. Partial denaturation of DNA at 90 degrees and 93.5 degrees resulted in the preferential destruction of transforming activity for the histidine and tryptophan markers. 3. Denaturation of DNA at 100 degrees followed by chromatography on methylated albumin yielded five fractions, two of which exhibited residual activity. Redenaturation at 100 degrees resulted in the interconversion of four out of the five fractions. Redenaturation of fractions labelled with (15)N and (2)H suggested the presence of a specific component that did not readily take part in the interconversions.  相似文献   
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The inhibitory effect of trypsin on the cytotoxicity of staphylococcal enterotoxin B acting with human embryonic intestine cell cultures was examined. Trypsin treatment of the cells rendered them resistant to enterotoxin for a period of 48 hr. The resistance increased proportionally with increased time of exposure of the cells to trypsin. Neither ethylenediaminetetraacetic acid nor scraping, which were used as alternate means of cell suspension, caused any resistance to the toxin. The effect is enzymatic and appears to be similar to the inhibitory action of trypsin and chymotrypsin on the attachment of polioviruses and coxsackieviruses to HeLa cells.  相似文献   
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International Microbiology - Acinetobacter baumannii is an opportunistic human pathogen that has become a global threat to healthcare institutions. This Gram-negative bacterium is one of the most...  相似文献   
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OBJECTIVE--To assess the validity, reliability, and acceptability of the short form 36 (SF 36) health survey questionnaire (a shortened version of a battery of 149 health status questions) as a measure of patient outcome in a broad sample of patients suffering from four common clinical conditions. DESIGN--Postal questionnaire, followed up by two reminders at two week intervals. SETTING--Clinics and four training practices in north east Scotland. SUBJECTS--Over 1700 patients aged 16-86 with one of four conditions--low back pain, menorrhagia, suspected peptic ulcer, or varicose veins--and a comparison sample of 900 members of the general population. MAIN OUTCOME MEASURES--The eight scales within the SF36 health profile. RESULTS--The response rate exceeded 75% in the patient population (1310 respondents). The SF36 satisfied rigorous psychometric criteria for validity and internal consistency. Clinical validity was shown by the distinctive profiles generated for each condition, each of which differed from that in the general population in a predictable manner. Furthermore, SF36 scores were lower in referred patients than in patients not referred and were closely related to general practitioners'' perceptions of severity. CONCLUSIONS--These results provide support for the SF36 as a potential measure of patient outcome within the NHS. The SF36 seems acceptable to patients, internally consistent, and a valid measure of the health status of a wide range of patients. Before it can be used in the new health service, however, its sensitivity to changes in health status over time must also be tested.  相似文献   
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