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1.
NV Zheleznova SL Mukomolov AB Zhebrun FS Noskov II Malkova EP Shargorodskaia AD Al'tshte?n VA Pliutnikova IN Lavrent'eva NN Ptichnikova 《Canadian Metallurgical Quarterly》1996,(5):49-53
The use of a recombinant poxvirus (RPV) strain, expressing HBsAg in the process of reproduction in different bioreactor systems under stationary and bioreactor conditions of cultivation, made it possible to obtain highly purified HBsAg. The identity and purity of HBsAg was confirmed by the analysis of its amino acid composition, SDS electrophoresis in polyacrylamide gel, electron microscopy and high-performance liquid chromatography. Good prospects of the use of RPV-expressed gene engineering HBsAg as the basis vaccines against hepatitis B was demonstrated in 10 experimental batches of vaccine. All batches of the preparation had pronounced immunogenicity and were safe and nontoxic in animal experiments. The ID50 of experimental batches did not exceed 211 ng/ml, which, according to the data of comparative experiments, was lower than, or equal to, corresponding values of analogous foreign commercial preparations, based on plasma or yeast HBsAg. 相似文献
2.
NN McGihon 《Canadian Metallurgical Quarterly》1996,34(6):31-35
1. Most psychiatric and mental health professionals are experienced with writing in some form as a tool for encouraging patients to express feelings and identify stressors. 2. Narrative writing, or journal writing, can also help patients identify areas of conflict in their lives and to clarify complicated issues. 3. Writing can be used effectively with patients who are reluctant or embarrassed to speak openly in one-on-one interactions. 相似文献
3.
OBJECTIVES: Injury is the leading cause of death in the male working population of Brazil. An important fraction of these deaths are work related. Very few cohort studies of steel workers, and none from developing countries, have reported on mortality from injuries. This paper analyses mortality from work and non-work related injuries among Brazilian steel workers. METHODS: Deaths during employment from 1 January 1977 to 30 November 1992 were analysed in a cohort of 21,816 male steel workers. Mortality rates specific for age and calendar year among the workers were compared with those of the male population of the state where the plant is located. Work related injuries were analysed by comparing the mortality rates for different subgroups of the cohort. RESULTS: The number of deaths (391) was less than half that expected based on death rates of the general population. Over 60% (242) of deaths were due to injuries. Mortality from most causes was substantially below that in the general population, but that from unintentional injury, was 50% above that of the general population. Standardised mortality ratios (SMRs) were highest for the youngest and the oldest employees and for labourers and clerical workers. Mortality from motor vehicle injury was twice that expected from population rates (SMR = 209, 95% confidence interval (95% CI) 176-244). There was a 67% fall in the age adjusted mortality from occupational injuries in the study period. CONCLUSION: The healthy worker effect in this cohort was greater than that commonly found in studies of occupational groups in developed countries, probably because of a greater socioeconomic gap between employed and unemployed populations in Brazil, and unequal distribution of health care resources. Mortality was especially high for motor vehicle injuries. The fall in mortality from occupational injuries during the study period was probably due to improvement in safety standards, increased automation, and better medical care. There is a need to investigate risk factors for unintentional injuries among steel workers, especially those due to motor vehicle injuries. Prevention of occupational and nonoccupational injuries should be a main priority in Brazil. 相似文献
4.
M Cuchacovich NN Tchernitchin H Gatica R Wurgaft L Contreras AN Tchernitchin 《Canadian Metallurgical Quarterly》1996,124(2):160-169
BACKGROUND: The target cellular response to glucocorticoids is proportional to the concentrations or affinity of specific receptors to these substances. AIM: To look for a correlation between glucocorticoid receptor concentrations in synovial wall cells and the clinical response to steroidal treatment in patients with rheumatoid arthritis. PATIENTS AND METHODS: Twenty eight patients with rheumatoid arthritis were studied. Each subject was subjected to a synovial biopsy, in which a dry radioautographic technique for diffusible compounds was used. Patients were treated afterwards with three 500 mg intravenous pulses of methilprednisolone. RESULTS: A mean of 44.8% of synovial cells (range 30.1-62.8%) had binding sites for 3H dexamethasone. All patients had a significant clinical improvement after methylprednisolone. Multiple regression analysis did not show a correlation between clinical response and glucocorticoid receptor concentration. CONCLUSIONS: The lack of association between glucocorticoid receptor concentrations and clinical response could be due to the large steroid dose used, that saturated all available receptors. 相似文献
5.
Oligonitrophilic bacteria were cultivated on a medium containing only 2.5--10.0 mg/litre of nitrogen compounds. They assimilated elementary nitrogen only after utilization of these nitrogen compounds during growth and formation of nitrogen-fixing enzyme system. Their cells grown on a medium containing high concentrations of bound nitrogen did not fix nitrogen during further incubation in the atmosphere of 15N; therefore, the enzymes involved in nitrogen fixation were induced. These organisms are characterized by diauxia during their growth on media containing "start" doses of nitrogen. Enzymes catalysing nitrogen fixation in azotobacter are also induced. But, contrary to oligonitrophilic bacteria, the azotobacter does not require nitrogen compounds in the medium in order to adapt to molecular nitrogen, and its growth curve is not of a biphasal character. These data and the evidence of other authors suggest that all nitrogen-fixing microorganisms are characterized by the induced, not constitutive, enzymes involved in reduction of molecular nitrogen. 相似文献
6.
The authors' experience with 45 papillosphincterotomies, performed for diseases of bile passages and chronic pancreatitis, is reported. The details of the operative technic, employed by the authors, are described. The technic of papillosphincterotomy on a conus-shape sound by means of a "laser scalpel" proved to be the most perfect one. Careful observation of the surgical technic made it possible to gain favourable results--only 1 of 45 operated patients died. Papillosphincterotomy is largely advocated in stenoses and concretions in the large duodenal papilla, strictures of choledocho-duodenoanastomoses, care should be taken not to overwiden indications to the operation concerned. 相似文献
7.
Syed Ali Fathima S. J. Lalitha T. Ahmad Faiyaz Karthick S. 《Wireless Personal Communications》2022,124(2):1815-1839
Wireless Personal Communications - Wireless Underground Networks comprise the ability to constantly monitor several physical parameters such as ground temperature, water level and soil condition,... 相似文献
8.
NN Petrovichev OV Chistiakova AV Smirnov TD Rudinskaia VS Poltoranina 《Canadian Metallurgical Quarterly》1995,57(4):25-30
Anti-macrophage monoclonal antibody (Mab) D-11 was tested in surgical material and biopsies of non-epithelial tumors and tumor-like lesions from 181 patients in order to assess possibility of using this Mab for diagnosis of histiocytic tumors, malignant fibrous histiocytoma in particular. The study was performed in parallel on cryostat sections and smears by immuno-peroxidase method. It is established that D-11 reacts positively with both histiocytic tumors and tumors of other genesis this being a limiting factor in differential diagnosis of histiocytic tumors. However, taking into consideration 100% of positive results with histiocytic tumors only, this antibody can be used for exclusion of tumors studied from the group of histiocytomas in cases of negative reaction. 相似文献
9.
10.
Kelly D Singh A Barrett CA O'Sullivan C Coughlan C Laffir FR O'Dwyer C Ryan KM 《Nanoscale》2011,3(11):4580-4583
A facile spin cast route was developed to convert perpendicularly aligned nanorod assemblies of cadmium chalcogenides into their silver and copper analogues. The assemblies are rapidly cation exchanged without affecting either the individual rod dimensions or collective superlattice order extending over several multilayers. 相似文献