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991.
Air-surgeons of the sanitary aviation department of the Vologda Regional Hospital analysed 279 summons to patients with acute gastrointestinal hemorrhage living in the districts of the region. They came to the conclusion that emergency gastroduodenoscopy allowed air-surgeons to identify the source of the bleeding in 97.64% of patients, determine the rational therapeutic tactics, and reach a well-grounded decision on evacuation of the patients to the regional hospital, as a result of which mortality reduced by more than half. 相似文献
992.
The effect of ethylene glycol on rat hepatic microsomal cytochrome P-450 was studied in vitro and in vivo. The destruction of cytochrome P-450 was not seen in vitro. The addition of 1 mM NADPH also did not change. When ethylene glycol was added to drinking water at a concentration of 1.0% for 7 days, there was no change in the contents of microsomal protein, cytochrome P-450, b5 and heme. While NADPH-cytochrome C reductase activity of the exposed group did not change, NADH-ferricyanide reductase activity increased significantly. 相似文献
993.
The doubly labelled water method was used to estimate energy expenditure in 20 formula-fed infants (10 aged 1 month and 10 aged 4 months). We then compared the energy expenditure values with energy balance values calculated from energy intake and energy cost of growth. Our purpose was to compare various published equations for calculating CO2 expiration rates (and thus energy expenditure values) from the isotopic data. Those equations in which we used measured values for 18O and 2H isotope dilution spaces and estimated or measured values for insensible water losses yielded energy expenditure values (69.7 +/- 8.4 kcal/kg/d) that agreed most closely with energy balance data (70.3 +/- 11.9 kcal/kg/d). Equations in which we used a constant ratio of 1.03 between the 2H and 18O isotope dilution spaces resulted in energy expenditure values (66.3 +/- 10.2 kcal/kg/d) lower than those predicted by the energy balance data. Data analysis by nonlinear curve fitting compared to logarithmic transformation did not alter the estimates of energy expenditure obtained in these infants. 相似文献
994.
Air-pouch-type inflammation was induced by injecting sodium carboxymethyl cellulose solution containing leukotriene C4 (LTC4, 3.20 x 10(-7) M, 0.2 micrograms/ml) and prostaglandin E2 (PGE2, 5.68 x 10(-6) M, 2.0 micrograms/ml), platelet-activating factor (PAF, 1 x 10(-6) M, 0.52 micrograms/ml), or 12-O-tetradecanoyl phorbol 13-acetate (TPA, 1.62 x 10(-6) M, 1.0 micrograms/ml) into an air pouch made on the dorsum of rats. Vascular permeability and tissue edema formation were significantly increased by injecting the phlogogen solution. The histamine level in the pouch fluid was dramatically increased by injecting TPA but not by LTC4 and PGE2, or PAF. Injection of isoproterenol or procaterol with the phlogogen solution produced dose-dependent suppression of both vascular permeability increase and tissue edema formation. However, the TPA-induced increase in the histamine level was not suppressed in parallel with the decrease of vascular permeability or tissue edema formation. These results indicate that beta-agonists suppress vascular permeability response and local tissue edema formation not by inhibiting mast cell degranulation, but by inhibiting the reactivity of the local vasculature to chemical mediators such as arachidonate metabolites, PAF, and histamine and serotonin released from mast cells. 相似文献
995.
Cell survival and DNA double-strand break repair following X-ray or neutron irradiation of V79 cells
We have investigated the effects of 250kVp X-rays and 2.3 MeV (mean energy) neutrons on the cell survival, DNA double-strand break (dsb) induction and repair (using the Kohn neutral elution technique) in V79 cells. The lethal effects of neutrons were shown to be significantly greater than for a similar dose of X-rays (RBE = 3.55 at 10 per cent survival). However, the RBE for dsb induction, in a dose range of 10-50 Gy, was 1. On investigating the repair of DNA dsb induced by either X-ray or neutron irradiation, clear differences in the pattern of repair were found. Both a fast and a slow component of repair were seen in both cases; the former, however, was reduced following neutron irradiation and, since the amount of slow repair was similar in both cases, this resulted in proportionally more unrejoined breaks after neutrons. These experiments were carried out with elution buffer at pH 9.6; however, when similar experiments were performed at pH 7.2 the results obtained support our earlier findings. We suggest that these differences in DNA dsb repair reflect basic differences in the nature of the lesions induced by high- and low-LET ionizing radiations. 相似文献
996.
997.
A Joseph S Abraham S Bhattacharji J Muliyil K R John N Ethirajan K George K S Joseph 《World health forum》1988,9(3):336-340
A study was made on the causes of unsatisfactory progress in immunization coverage in an area of Tamil Nadu, southern India. The findings led to the appointment of additional community health workers (CHW), improvement in supervision, the enhancement of accessibility to services through an increase in the number of peripheral clinics and the organizing of temporary clinics, and the concentration of effort on underprivileged groups. As a result, immunization coverage was more than doubled. The Community Health and Development Project, a primary health care program serving 68 villages since 1981 with a population of about 80,000 was the site of the study which was conducted by discussions with staff and various members of the community. Issues explored were nonacceptance or dropout reasons, and specific factors affecting immunization coverage. A special effort was made to obtain the views of staff working at the periphery, particularly CHWS. The service area was divided into 4 sectors and the CHWS, auxiliary nurse midwives, community health nurses and other development staff in each were brought together for discussions. Views were also solicited from mothers' clubs and youth groups and in meetings with village leaders. Issues raised were further considered by supervisory staff. Statistical studies and other studies were done to clarify doubtful issues and test hypotheses emerging from the discussion. Poor immunization coverage was linked to inadequate supervision of CHWs, scattered communities (village with houses clustered together had better acceptance rates), difficulty of access to health services (distance factors), and low economic and educational status. In light of the study findings, community health workers were increased from 42 in 1984 to 57 in 1987 to cover all the villages, with modifications in selection method to make the worker acceptable to all sections of the villages; abolishment of the auxiliary nurse midwife and addition of a new category, health aide, to link the CHW and the community health nurse, increase of peripheral clinics from 37 to 75 and holding of more temporary clinics, more efforts to reach all socioeconomic groups and increased health education through film shows, drama, and work with village groups. 相似文献
998.
999.
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