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991.
I Szadkowska-Stańczyk T Rogaczewska W Sobala K Widerkiewicz 《Canadian Metallurgical Quarterly》1995,46(6):563-574
The study covered the work environment of a big plant producing sulfate cellulose, paper and paperboard. Measurements of chemical substance concentrations, performed by a local plant laboratory during the years 1976-1991, were analysed with reference to production departments and particular workplaces. Out of 37 substances under study, 16 were found in the air of workplaces. Their concentrations exceeded periodically hygienic standards. The most frequent excess of TLV applied to such compounds as wood dust (including hard beechwood), non-organic dusts containing 2-50% of crystalline silica and below 2% of silica, welding fumes, furfuryl aldehyde, sulfur dioxide, phenol and hydrogen sulfide. A computer-aided registrer of hygienic data facilitated the follow-up of dynamics of exposure to toxic compounds of workers employed at given workplaces. 相似文献
992.
Blood vessels were examined within epineurium of 38 ischiadic nerves from corpses of men and women aging 26 to 65 years. The studies demonstrated that large eyeholed and fine meshed vascular plexuses are formed in both components of ischiadic nerve. The plexus maintain communication with axial arterial and venous vessels which run in the outer layer of epineurium and with interfascicular vessels located in connective tissue of interfascicular epineurium. 相似文献
993.
J Borak J Cie?licki W Szelenberger H Wilczak-Szadkowska M Koziej J Zieliński 《Canadian Metallurgical Quarterly》1993,27(1):43-55
The aim of the research was to discover the level of change observed in cognitive functions and personality variables in patients ill with obstructive sleep apnea prior to and after CPAP treatment. Data was collected from 20 male patients ill with a severe form of obstructive sleep apnea whose physiological symptoms were correlated with the results of cognitive functions and personality variables. It was concluded that obstructive sleep apnea patients have lowered; attention, concentration, speed of learning verbal and visual stimuli and speed of learning visual-motor tasks. An increased level of depression was noted together with increased anxiety and psychological tension. In half of the group irregular EEG recordings and a pathological result on the Benton Test suggests organic damage to the CNS. These changes were negatively correlated with amounts of REM and 3 + 4 NREM sleep, but were positively correlated with the level of sleep hypoxemia. The results suggest that after 3 months of CPAP treatment affect improved significantly. The observed tendency for cognitive functions to improved was not statistically significant. 相似文献
994.
St. Rashkov Y. Stefanov Z. Noncheva M. Petrova Ts. Dobrev N. Kunchev D. Petrov St. Vlaev V. Mihnev S. Zarev L. Georgieva D. Buttinelli 《Hydrometallurgy》1996,40(3):319-334
The electrochemical oxidation processes and phase formation on binary PbAg and PbCa, and ternary PbAgCa alloys during anodic treatment of the electrodes for conditions in a sulphuric acid electrolyte were investigated.The electrochemical behaviour of lead and its alloys was studied by the cyclic voltammetry method (CVA). X-ray and SEM were used for the phase composition and surface structure analysis. It was established that only the ternary plastically treated PbAg 0.5%-Ca 0.11% alloys reveal similarities to the industrially applied PbAg 1 % anodes. It may be assumed in the case of ternary alloys that the catalytic layer is composed of a dense non-conductive MnO2 layer of crystals serving as basic sites for oxygen evolution. 相似文献
995.
Digital diseases in cattle are common. Cattle affected by digital disorders do not always respond to medical therapy and often need surgery. A thorough examination of the digits and radiographic evaluation help the clinician to choose the appropriate treatment and surgical approach. Age, sex, weight, type of production, and environment of the cattle also should be considered in choice of therapy. 相似文献
996.
At the end of a hybridoma batch culture, the cells are usually discarded after separation from the culture broth. If, however, they are aseptically recycled into the reactor, the production process can be resumed simply by the addition of fresh medium. This cycle can then be repeated several times consecutively. In a test case, with a mouse hybridoma, we found antibody yields for each cycle in the same range as for a standard batch. In a 15 1 stirred tank reactor we could, within 6 days, produce 2.8 g of monoclonal antibody (MAb). This type of reactor operation allowed a doubling in the reactor volumetric productivity (mg/l/day). 相似文献
997.
About 20% of all women with insulin-dependent diabetes mellitus (IDDM) have menstrual irregularities. Eight percent have amenorrhea. Fluctuations in blood glucose and insulin concentration are probably contributing factors, but the irregular menstrual cycles are mainly caused by disorders in the central ovulatory mechanisms. Hypothalamic GnRH release is regulated by several neuropeptides. Dopamine and opiates exert an inhibitory effect, and there is evidence for an abnormally high dopaminergic hypothalamic activity among women with IDDM. There might also be disorders of the opioid, serotonergic and GABA'ergic systems, but the consequences of there possibilities remain uncertain. 相似文献
998.
G Broda CE Davis A Pajak OD Williams SL Rywik E Baczyńska AR Folsom M Szklo 《Canadian Metallurgical Quarterly》1996,16(2):339-349
HDL cholesterol (HDL-C) levels are inversely related to coronary heart disease (CHD) risk, and HDL-C distributions vary among countries. Poland is one of the few developed countries in which CHD rates are increasing at the same time that US rates have been falling, but whether these differences are explained by differences in risk factors such as HDL-C has not been determined. To examine this possibility, levels of HDL-C and its subfractions were compared in US and Polish urban and rural men and women aged 45 to 64 years. Age-adjusted HDL-C means were 0.20 mmol/L higher in urban Polish men and 0.37 mmol/L higher in rural Polish men than in their US counterparts (P < .0001); means in urban Polish women were 0.06 mmol/L higher (P < .05) and in rural Polish women 0.09 mmol/L higher (P < .001) than in their US counterparts. Adjustment for age, education, alcohol intake, smoking, BMI, heart rate, and menopause status (in women) had little effect on differences. Means of HDL2 and HDL3 levels showed similar between-country differences, although differences were minimal for HDL2 in urban men and women, and HDL3 means did not differ between rural women. BMI was inversely related to HDL-C and both subfractions in all gender-country-site strata (P < .001), and alcohol was directly related to HDL-C (P < .001) in all strata except Polish women. Cigarette smoking was negatively related to HDL-C and both subfractions in all US samples except HDL2 in urban men, whereas in Polish samples, significant associations were found only in urban women for HDL-C and in rural and urban women for HDL3. Age, heart rate, and education showed inconsistent or no association with HDL-C and its subfractions in either country. This profile of HDL-C and its subfractions in Polish samples contrasts sharply with the opposite trend in CHD mortality rates, which suggests either that other risk factors may account for the trends or that the relationship between HDL-C and CHD may differ between the two countries. 相似文献
999.
W Banasiak E Metner P Ponikowski M Wilczyński I Owczarek J Petruk-Kowalczyk C Telichowski 《Canadian Metallurgical Quarterly》1996,95(5):402-413
The aim of this study was to assess the effects of myocardium organic damage on time-domain parameters of atrial signal-averaged ECG (ASAECG) in patients with electrically induced paroxysmal atrial fibrillation (PAF). The investigation was done in 120 patients with subjective symptoms of cardiac rhythm disorders suggesting atrial fibrillation and for further analysis were selected 51 patients in whom atrial PAF was induced during transoesophageal pacing (TEP). Patients were divided according to organic damage of myocardium-38 pts (24 male and 14 female, mean age 52.1 +/- 11.6-group I) and without-13 pts (9 male and 4 female, mean age 35.4 +/- 9.9 -group II). In all two dimensional echocardiographic examination, 24-hours Holter monitoring, exercise testing and TEP were made. Recording of ASAECG was done with a commercially available system HIPEC-200 HA Aerotel. The following time-domain parameters of ASAECG were calculated: the root mean square voltage of the terminal 10, 20, 30 ms of the filtered P-wave (RMS 10, 20, 30) and time duration of filtered P-wave (PWD) and also time duration of P-wave from Frank's leads X, Y, Z (XP, YP, ZP). Atrial late potentials (ALP) were defined as the presence of two parameters: RMS 10 < 4 microV and PWD > 123 ms. If we compared time-domain parameters of ASAECG between examined groups it occurred that only the values of PWD attained statistically significant differences, respectively 123.3 +/- 15.4 ms vs 115 +/- 11.2 ms, p < 0.05. In 14 (36.8%) patients from first group and in 2 (15.4%) patients from second ALP were confirmed. We concluded that presence of myocardium organic damage have essentially influenced on time duration of filtered P-wave. 相似文献
1000.
IM St George 《Canadian Metallurgical Quarterly》1996,109(1014):15-17
The 1982 publication of the Resolution journal of Johann George Reinhold Forster provided justification for his recognition as a scientist, and gave a remarkable insight into his character. It also included an account of an illness suffered by many of the sloop's crew, including Forster, after a period ashore at Queen Charlotte Sound. The symptoms of the illness were remarkably similar to those now clustered as the chronic fatigue syndrome. 相似文献