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991.
Reversal of ethanol and indomethacin-induced suppression of hepatic DNA synthesis by 16,16-dimethyl prostaglandin E2 总被引:1,自引:0,他引:1
Investigations were undertaken to determine effectiveness of 16,16-dimethyl prostaglandin E2 (dmPGE2) in overcoming the suppressive effects of ethanol and/or indomethacin on hepatic DNA synthesis. Adult litter mate Sprague-Dawley rats were subjected to sham operation or partial hepatectomy. Immediately after partial hepatectomy, and at 8-hr intervals for 24 hr, the rats were given: (a) ethanol with and without dmPGE2 or (b) indomethacin with and without ethanol and/or dmPGE2. DmPGE2 produced a significant increase in DNA synthesis in sham-operated (p less than 0.001) and untreated partially hepatectomized animals (p less than 0.025). Ethanol and indomethacin caused a 6- and 18-fold reduction, respectively, in hepatic DNA synthesis following partial hepatectomy. DmPGE2 overcame the inhibitory effect of ethanol (p less than 0.005) and indomethacin (p less than 0.0005) in partially hepatectomized animals. Mitoses were decreased concomitantly with ethanol and/or indomethacin-induced reduction in DNA synthesis and increased with administration of dmPGE2. It is concluded that dmPGE2 increases hepatic DNA synthesis and regeneration in normal rat liver and overcomes their inhibition when ethanol and/or indomethacin is given after partial hepatectomy. Timing of dmPGE2 administration is crucial. When given 30 min before ethanol, it completely inhibits suppression of regenerative activity; omission of this "priming" dmPGE2 dose results in only 44% of DNA synthesis obtained in control animals. 相似文献
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996.
T G Wang Y D Chen H Yang R C Peng 《Asia-Pacific journal of public health / Asia-Pacific Academic Consortium for Public Health》1987,1(2):39-43
80% of China's 1 billion population is rural. In response to the changing situation in rural health care work subsequent to profound economic rural structural reform, appropriate measures in Chinese rural health care work were taken. All levels of leaders in health care and other departments were instructed to continue the rural health care policy of "prevention first," and to expand the functions and tasks of prevention. Rural areas were to given top priority. To reform the current health organizational structure it was necessary to take into account several realities: The rural birth rate has dropped radically since liberation, as has the mortality rate. Life expectancy has increased, the combined effect being a population that is aging rapidly: people 65+ years old comprised 4.91% of the population in 1982. 32.2% of rural families are 1-child families, and the safeguarding of the health of children continues to be a high priority, as does the prevention of cardio- and cerebrovascular disease and malignant tumors, which as cause of 54.91% of mortality, has replaced infectious diseases as the main health threat. Occupational disease have become alarmingly more common as the effort to expand rural industry advances. The 3-level health care network is to continue to be reinforced: county facllities for training and care of complicated diseases, integrating multiple functions that were previously separate, township rural health centers for the development of prevention teams, and village level doctors. The rural medical system must, among other things, transform the medical model to a "biological, psychological, and social" medical model, mobilize various social sectors, and attempt to collect funds from various sources to support health care work and the prevention of disease. 相似文献
997.
The Acetylenes from Atractylodes macrocephala 总被引:1,自引:0,他引:1
Chen ZL 《Planta medica》1987,53(5):493-494
The investigation of ATRACTYLODES MACROCEPHALA afforded in addition to known compounds, esters of tetradeca-2,8,10-triene-4,6-diyne-1,12,14-triol. The structures were elucidated by spectroscopic methods and chemical evidence. 相似文献
998.
Deficient expression of enhanced reactivation of parvovirus H-1 in ataxia telangiectasia cells irradiated with X-rays or u.v. light 总被引:1,自引:0,他引:1
Cells of patients with ataxia telangiectasia (AT), an inheriteddisease characterized by a high propensity to cancer, are hypersensitiveto ionizing radiation. We investigated whether the hyper-radiosensitivityof AT cells correlated with a defect in their constitutive and/orconditional ability to rescue a damaged exogenous virus. Forthat purpose, parvovirus H-1, a single-stranded DNA virus whoseintranuclear replication mostly relies on host cell functions,was used as a probe. The survival of u.v.-or -irradiated H-1was measured in X-, u.v.- or mock-irradiated human cells ofnormal (NB-E) or AT (AT5BIVA) origin. -irradiated H-1 survivedto similar extents in untreated normal and AT cell lines. BothX- and u.v.-irradiatlon induced normal cells to achieve an enhancedreactivation (ER) of -- or u.v.-damaged H-1. In contrast, neitherdose-effect curves nor time course revealed significant levelsof ER expression after X- or u.v.-irradiation in AT5BIVA cells.Our results suggest that the impairment of ER of damaged parvovirusesmay constitute a marker of the AT cell phenotype and be relatedto the radiosensitivity of AT cells. 相似文献
999.
Radiologic and manometric correlation in "nutcracker esophagus" 总被引:1,自引:0,他引:1
D J Ott J E Richter W C Wu Y M Chen D W Gelfand D O Castell 《AJR. American journal of roentgenology》1986,147(4):692-695
"Nutcracker esophagus" is a newly described esophageal motor disorder seen in some patients with chest pain and/or dysphagia and characterized manometrically by normal primary peristalsis with distal contractions of high amplitude. The radiographic and manometric examinations in 20 patients with nutcracker esophagus were correlated. Normal primary peristalsis was observed radiographically in 16 patients, and a nonspecific motor disorder was diagnosed in the remaining four patients. Mild-to-severe nonspecific tertiary activity was seen in about half of the patients, esophageal wall thickness was normal. It is concluded that nutcracker esophagus is primarily a manometric diagnosis made in the appropriate clinical setting, and that the radiographic findings are normal or nonspecific. 相似文献
1000.
本文报道一例用病理组织学、免疫组织化学和免疫电镜综合确诊的多克隆性IBL样T细胞性淋巴瘤。讨论了这三种病理研究手段综合应用在本例诊断中的意义。指出免疫电镜在确定阳性反应细胞的细微形态上较光镜有明显优越性。 相似文献