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Rats were killed after 6 weeks of continuous ingestion of the pneumotoxic alkaloid monocrotaline (2.2 mg/kg/day), the neutrophil elastase inhibitor SC39026 (60 mg/kg/day), or both. Pulmonary reactions were evaluated by light and electron microscopy. Lung endothelial function was monitored by angiotensin converting enzyme (ACE) activity, plasminogen activator (PLA) activity, and prostacyclin (PGI2) and thromboxane (TXA2) production. Lung hydroxyproline content was measured as an index of interstitial fibrosis. Cardiac right ventricular hypertrophy was determined by the right ventricle to the left ventricle plus septum weight ratio (RV/LV + S). Rats receiving SC39026 alone did not differ significantly from untreated control animals with respect to any of the quantitative endpoints, although rarefaction of Type I pneumocytes was observed in the electron micrographs of these animals. Monocrotaline-treated rats, in contrast, developed a significant increase in RV/LV + S, and exhibited pulmonary edema, inflammation, fibrosis, and muscularization and occlusive mural thickening of the pulmonary small arteries and arterioles. These monocrotaline-induced structural changes were accompanied by decreased lung ACE and PLA activities, and increased PGI2 and TXA2 production, and by an increase in lung hydroxyproline content. Cotreatment with SC39026 ameliorated the monocrotaline-induced pulmonary vascular wall thickening and the cardiac right ventricular hypertrophy. These data suggest that inappropriate neutrophil elastase activity contributes to monocrotaline pulmonary vasculopathy and hypertension. On the other hand, cotreatment with SC39026 had no significant effect on the severity of the monocrotaline-induced lung inflammatory reaction, the pulmonary endothelial dysfunction, or the increase in lung hydroxyproline content. 相似文献
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Hung-Tao Hsu Stephen J. Ryan 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1986,224(1):1-6
In one eye each of four cynomolgus monkeys, an 8-mm penetrating injury was made through the equator; there was retinal perforation with vitreous loss. None of the four eyes with this injury developed posterior vitreous detachment or retinal detachment during a follow-up period of 8 months to 1 year.Another group of 26 monkeys had the same injury but also had 0.5 ml autologous whole blood injected into the vitreous at the time of injury. The eyes were examined weekly and enucleated at scheduled intervals from 1 day to 52 weeks post-injury. Posterior vitreous detachment occurred at the earliest at 2 weeks post-injury, and was ultimately present in 91% of the eyes. Vitreous detachment can occur either as a separation at the level of the internal limiting membrane or as a cleavage within the cortical vitreous. Retinal detachment occurred at the earliest at 8 weeks post-injury, and eventually was present in 50% of the eyes. The retinal detachment was tractional; no retinal breaks were detected in any of the eyes.This study was supported by grants EY02061 and EY03040 from the National Institutes of HealthPresented at the 1984 meeting of the Club Jules Gonin in Lausanne, Switzerland 相似文献
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J. Bryan Page 《Journal of urban health》2005,82(3):iii35-iii43
Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors. 相似文献
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Pilar Nicolás 《Hereditary cancer in clinical practice》2007,5(3):144-152
The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing. 相似文献
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Kevin Gruffydd-Jones Sandra Hollinghurst Sabbi Ward Gordon Taylor 《The British journal of general practice》2005,55(521):918-923
BACKGROUND: There is a high non-attendance rate for traditional clinic-based routine asthma care in general practice. Alternative methods of providing routine asthma care need to be examined. AIM: To examine the cost and effectiveness of targeted routine asthma care in general practice using telephone triage, compared to usual clinic care. DESIGN OF STUDY: An open randomised controlled trial. SETTING: A single semi-rural practice in the southwest of England. METHOD: Adult patients with asthma were randomised to receive either their routine asthma care in the surgery or care by telephone triage. Asthma control parameters, health status and NHS resource utilisation were measured over the 12-month study period. RESULTS: One hundred and ninety-four patients were randomised and 35% per cent more patients (n = 84 versus n = 62) received more than one consultation in the telephone group. Asthma control as measured by the asthma control questionnaire (ACQ) was similar in the clinic and telephone groups: mean change in ACQ = -0.11 (95% CI = -0.32 to 0.11) versus -0.18 (95% CI = -0.38 to 0.02). Mean NHS costs were 210 pounds sterling per patient per year in the telephone group compared to 334 pounds sterling in the clinic group (P-value of bootstrapped difference = 0.071). CONCLUSION: Targeted routine asthma care by telephone triage of adult asthmatics can lead to more asthma patients being reviewed, at less cost per patient and without loss of asthma control compared to usual routine care in the surgery. 相似文献
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