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101.
The CO2 laser can be used for the treatment of various lesions of the eyelids and peri-orbital region with the advantage over other modalities of precise, controllable, hemostatic, non contact atraumatic ablation with the reduction of post-operative pain and improved cosmetic results. Its application in palpabral and peri-orbital surgery is recommended.  相似文献   
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In the present work, we studied the role of polymorphonuclear leukocytes (PMN) in aged individuals and coronary heart disease (CHD)-bearing patients, two physiopathological processes associated with overproduction of reactive oxygen species (ROS). The effects of antioxidant supplementation on the functional activity of PMN from CHD patients were also determined. The function of PMNs was evaluated by measuring of phagocytosis, killing activity, and ROS production. Luminol amplified chemiluminescence (CL) was used to estimate ROS production by stimulated PMNs. Total cholesterol and the LDL-cholesterol fraction from CHD patients were found to be higher than those recommended, returning to normal levels after antioxidant therapy. PMN CL of CHD patients was found to be higher than the associated control groups. Antioxidant therapy administrated to CHD patients lead to an increase in the killing activity accompanied by a decrease in PMN CL of these subjects. The study also showed that killing activity of PMN from human subjects over 60 years was significantly lower than the activity measured in younger subjects. PMN CL produced after stimulation was found to be positively correlated with the increasing age of human subjects (r=.946, p < .01).  相似文献   
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Salmonella is a Gram-negative bacterium that has been implicated in several food-borne poisoning outbreaks. Poultry products are considered to be the major vehicles of food-borne poisoning caused by Salmonella. The resistance of Salmonella, isolated from different stages in a local poultry abattoir, to hypochlorous acid (HOCl) was studied. Isolates cultured in quarter strength Tryptone Soya Broth were treated with 72 ppm HOCl, incubated at 30 degrees C with shaking, and absorbance was measured at 660 nm every 20 min. A number of resistant isolates, which carried on growing following HOCl addition, were obtained. All the isolates from the bleeding stage were sensitive to HOCl, whereas those from the scalding stage were resistant to HOCl. Other stages had a population of resistant and sensitive isolates. It is evident that some Salmonella will grow in the presence of concentrations of HOCl deemed to be inhibitory. Hence, an effective concentration of HOCl must be applied in poultry abattoirs to ensure that all the Salmonella are eradicated.  相似文献   
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Experiment INTERSTITIUM was performed on days 3, 170, 287, and 430 of the long-term MIR mission of the Russian cosmonaut-physician in order to evaluate reactivity of the system of hormonal regulation of homeostasis during LBNP sessions. Data of the experiment displayed different types of reaction of the volume controls to LBNP at the onset (F-3), in the course of and soon after recovery (R-4) from the extended mission which are signs of specific phases of adaptive shifts in the organism of cosmonaut. Exaggerated reactivity of the hormonal systems during LBNP in flight suggests more significant consequences of the test for the cardiovascular system of human in microgravity. The most expressed hormonal reaction to LBNP was documented at the very beginning of the postflight period. Plasma cGMP was materially reduced in the process of the mission and remained quite low on R-4; return of nucleotides to the norm was observed no earlier than on R-90. Complete recovery from the space mission took three months when the hormonal reaction to LBNP was same as prior to launch.  相似文献   
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The influence of acetamide (AA) on the native DNA molecule conformation has been studied by methods of flow birefringence and viscometry. On one hand, it was shown that hydrodynamical and optical behaviour of the macromolecule at extremely low additions of AA is qualitatively the same as in the presence of nonelectrolytes which stabilize the water structure. On the other hand, the influence of intermediate and large AA concentrations on the native DNA molecule conformation is qualitatively the same as of corresponding urea concentrations, which is known to be a structure-breaker. The influence of AA on the thermostability of the native DNA molecule as well as on the stacking-association constant of adenosine has been studied by a spectrophotometric method. The obtained data confirm the hypothesis of the importance of ion-dipole interactions between nonelectrolytes and the phosphate groups of the DNA molecule.  相似文献   
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In 11 machine experiments of recirculation the abilities of survival and functioning of livers of dwarf pigs perfused with human preserved blood were tested with the help of the eliminations of indocyanine green, galactose, bilirubin and ammonia from a closed circulation. Further urea-nitrogen were measured as indicator of the urea synthesis and bile secretion. The perfusion of the animal livers was carried out in 9 cases only through the portal vein. The values of the blood flow were between 0.4 and 1.0ml pro g liver tissue and minute in portal pressure values about 15 cm water column. Two recirculations were carried out with additional flow through the hepatic artery with about 1/5 of the whole blood flow. The results of the experiments described prove a pretty good functional performance of the perfused with human blood livers of dwarf pigs during several hours. The different animal livers, however, showed at the beginning as well as during the further course of the perfusion clear differences concerning their functional capacity. Decrease of the blood flow values below 0.5 ml pro g liver tissue lead to functional loss. The additional flow through the hepatic artery yielded no better results, compared with the only perfusion of the animal liver through the portal vein.  相似文献   
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