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981.
In this paper the investigation results of successional processes in the vegetative cover appearing due to succession starting
in native ecosystem inundation zone under Sayan-Shush reservoir influence are given. 相似文献
982.
R Linder A W Bernheimer N S Cooper J D Pallias 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1989,94(1):105-110
1. A high cholesterol diet caused guinea pig erythrocytes to become sensitive to lysis by cholesterol oxidase (CO), a protein not hemolytic to normal cells. 2. Lysis was associated with conversion of membrane cholesterol to its oxidation product (delta-4-cholesten-3-one). 3. Intravenous injection of CO to hypercholesterolemic guinea pigs produced a reduction in serum cholesterol, but was not lethal as it was in rabbits. 4. Homogenized spleen, liver and kidney from the hyperlipidemic animals were sensitive to in vitro cholesterol oxidation while tissues from non-lipemic animals were resistant to modification. 相似文献
983.
To study the protein permeability properties of the ventilated premature lung, we delivered groups of eight lambs at 122 and 135 days gestational age and ventilated the lambs equivalently. The lambs at 122 days gestational age had been treated with natural sheep surfactant at birth, and both groups of lambs had similar pH and blood gas values to 3 h of age. Three groups of lambs at 146 days gestational age also were studied for comparison; four lambs were ventilated to normalized PCO2 values, four lambs were ventilated equivalently to the premature lambs with supplemental CO2 used to normalize PCO2 values, and four lambs were treated with natural surfactant and ventilated similarly to the preterm lambs. The percent recovery into an alveolar wash and lung tissue of 131I-albumin given by intravascular injection and of 125I-albumin given into the airways was measured in each animal after killing at 3 h of age. Full-term lambs had a small bidirectional leak of albumin to and from the alveoli and lung tissue. The recovery of intravascular 131I-albumin in the alveolar wash was 5.8- and 4.1-fold higher in lambs at 122 and 135 days gestational age, respectively, than in full-term lambs. The loss of 125I-albumin from the airways and alveoli also increased as gestational age decreased. The bidirectional flux of albumin to and from the alveoli increased as gestational age decreased in the prematurely delivered and ventilated lambs. 相似文献
984.
Activity of cytosolic 5'-nucleotidase in regenerating rat liver after partial hepatectomy 总被引:1,自引:0,他引:1
The specific activity of the cytosolic 5'-nucleotidase in regenerating liver increased to 175% of the control level of sham-operated animals during the 2nd and 3rd day and remained elevated most of the experimental period. The total cytosolic 5'-nucleotidase activity of the regenerating liver reached the level of control rats between 2 and 3 days after the operation. The variation pattern of the enzyme, which was distinctly different from variations of other known phosphohydrolases, was strikingly similar to that of the salvage enzyme hypoxanthine/guanine phosphoribosyltransferase. 相似文献
985.
986.
987.
988.
In this paper we describe the use of punched feature cards in a general practice for 18 months. Its advantages are the low cost, speed of information retrieval, visible statistics, computer compatibility, accuracy, confidentiality, flexibility, and simplicity of setting up and collection of information. The system encourages the doctor to ask questions about his practice, and could readily be adopted in other practices. 相似文献
989.
The incubation of liver microsomes or mitochondria with glutathione, in the presence of electrophilic compounds, decreased the glutathione concentration in the incubation medium. Product analysis revealed that glutathione conjugates were formed. 相似文献
990.