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921.
922.
Unplanned pregnancies may occur if antibiotics are prescribed to women using the combined oral contraceptive pill. To investigate awareness of the potential for this interaction among general dental practitioners, the authors designed a cross-sectional questionnaire based study and sent it out to a random sample of GDPs in Scotland. 相似文献
923.
924.
LI Kugusheva VP Nesterov VI Rozengart GM Dorenskaia AM Kulieva 《Canadian Metallurgical Quarterly》1994,30(5):650-655
Studies have been made on enzymic hydrolysis of p-nitrophenylacetate (p-NPhAc), n-nitrophenylbutyrate (p-NPhBu) and indophenylacetate (IPhAc) by carboxylesterase (CE) from mouse blood plasma and liver as well as from caterpillar of the cotton worm haemolymph, intestine and fat body. Different KM and V max values were obtained for CE from these sources. The highest specific activity of CE from mouse liver and caterpillar intestine and fat body was observed with p-NPhBu. p-NPhAc is the best substrate for CE from mouse blood serum and caterpillar haemolymph. Carboxylesterases from mouse and caterpillar differed in their sensitivity to armine and paraoxone by 1-2 orders depending on the substrate used. Species and tissue differences in the kinetics of CE-catalyzed reactions with different substrates and inhibitors were revealed. 相似文献
925.
Slow potential recording was used for long-term monitoring of the penumbra zone surrounding an ischemic region produced by middle cerebral artery (MCA) occlusion in adult hooded rats (n = 32). Four capillary electrodes (El-E4) were chronically implanted at 2-mm intervals from AP -3, L 2 (El) to AP 0, L 5 (E4). Spontaneous or evoked slow potential waves of spreading depression (SD) were recorded during and 4 h after a 1-h MCA occlusion and at 2- to 3-day intervals afterward for 3 weeks. Duration of the initial focal ischemic depolarization was maximal at E4 and decreased with distance from the focus. SD waves in the penumbra zone were high at El and E2, low and prolonged at E3, and almost absent at E4. Amplitude of elicited SD waves was further reduced 3 days later and slowly increased in the following week. Cortical areas displaying marked reduction of SD waves in the first days after MCA occlusion either remained low or showed substantial (60%) recovery, the probability of which decreased with the duration of the initial focal ischemic depolarization and increased with the distance from the focus. It is concluded that the outcome of ischemia monitored by long-term SD recovery in the perifocal region can be partly predicted from the acute signs of MCA occlusion. 相似文献
926.
927.
928.
LA Shpagina MI Loseva TM Sukharevskaia VI Sharapov OV Sazonova SV Tret'iakov 《Canadian Metallurgical Quarterly》1996,68(12):15-19
171 iron-deficient painters and 20 subjects with chronic intoxication with aromatic hydrocarbons were studied in a large aircraft construction factory. After correlative analysis of iron metabolism, ferritin, erythrocytes, diameter and perimeter of reticulocytes, length of service three types of iron-deficiency were identified: typical, with evident toxicity, with a high risk of toxic damage. An important role of lipid peroxidation activity and toxic erythrocyto-membranopathy for pathomorphosis of iron deficiency anemia and progress of toxic anemia is demonstrated. A differential approach to treatment of different anemia variants was used. The treatment included membranoprotectors (alpha-tocopherol, essential, lypostabil) and unspecific detoxication (SUMS-enterosorbent, unitiol). 相似文献
929.
O. V. Minin 《Journal of Engineering Physics and Thermophysics》1998,71(5):906-916
Based on the principle of least action extended by the author to heat conduction in a solid, owing to the formal analogy between
time and absolute temperature stated in the 1980s by means of the formalism of the Hamilton—Jacobi equation an expression
is obtained for the ponderomotive thermodynamic force in a solid and a gas.
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 71, No. 5, pp. 917–926, September–October, 1998. 相似文献
930.
Data on physico-chemical properties and functional role of protein S-100 have been generalized. An analysis of literary data permits making a conclusion that the protein interaction with Ca2+ ions plays great part in its action mechanisms. Data are presented on the properties of the family of Ca-binding proteins similar to protein S-100 as to their structure. Peculiar attention is paid to the analysis of this protein function in the cellular nucleus, changing the degree of proteins phosphorylation and RNA synthesis. 相似文献