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A possibility was shown of cultivation of M. pneumoniae in the organ cultures of the trachea and the lungs of a pig embryo. 5-7-day guinea pigs, and 3-5-day chicks. The lung and tracheal explants of chicks possessed the greatest sensitivity to M. pneumoniae. M. pneumoniae strains were isolated from the nasopharyngeal smears and washings from the bronchi obtained in bronchoscopy of patients suffering from chronic pneumonia, with the use of organ culture of chick trachea. Explains of chick trachea could serve as a medium for the isolation of M. pneumoniae from the patients.  相似文献   
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In the current work we report on the synthesis of LiKB(4)O(7), Li(2)B(6)O(10), and LiCsB(6)O(10) borate glasses. The results for their piezo-optic, acousto-optic, acoustic, elastic, refractive, optical transmission, and optical resistance properties are also presented. It is shown that some of these glasses represent efficient acousto-optic materials that are transparent down to the vacuum ultraviolet range and highly resistant to laser radiation.  相似文献   
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Contents of iron, zinc, copper, manganese, nickel, lead and cadmium were determined in the brain, pectoral muscle, kidney, liver and bones of the Mallard (Anas platyrhynchos), a cosmopolitan, herbivorous duck species. Both immature (im; in the first year of life) and older (adult, ad) ducks were studied. The birds originated from wetlands in two areas in north-western Poland, one located in the S?ońsk waterfowl reserve (n = 32 im + 24 ad) and the other near the city of Szczecin (n = 21 im + 21 ad). There were numerous significant age-dependent differences in the metal contents of the organs of the Mallards obtained from near Szczecin (Sz) and/or S?ońsk (S). Copper contents in the brain (Sz and S), muscles (Sz) and kidneys (Sz) as well as cadmium contents in the liver (Sz, S), kidneys (Sz, S) and muscles (S) were observed to increase with age. Between-area differences in metal contents of individual organs were recorded as well. The S Mallard showed higher contents of iron and copper (in muscles, liver and kidneys), zinc (in liver and kidneys) and cadmium (in muscles, liver and kidneys), while the Sz ducks revealed higher contents of manganese and lead (in brain and bones). The differences observed may be related to the habitat specificity: the Sl?ońsk reserve is periodically flooded by the River Odra (Oder) waters that carry pollutants from a copper mining area 250 km away. On the other hand, the mid-field ponds near Szczecin are affected by pollutants, including those that are manganese-rich, generated by agriculture and traffic.  相似文献   
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The pulmonary arteriole remodeling in Wistar rats with respiratory infection induced by mycoplasma pneumoniae was observed using light microscopy and morphometry. The pulmonary artery pressure (PAP) and index of right ventricular hypertrophy (RVHI) were measured. The intimal and medial hypertrophy can be seen in the pulmonary arterioles, leading to vessel wall thickening and narrowing of the lumina. The total number of the pulmonary arterioles decreased (P < 0.01), and both pulmonary hypertension (Ppa 4.11 +/- 0.19 kPa) and right ventricular hypertrophy (RVHI = 34.96 +/- 3.91%) occurred. In addition, an interstitial pulmonary fibrosis (IPF) was found, in which the content of collagen in the lung tissue changed, i. e., type I collagen increased whereas type III one decreased, and the ratio of type I collagen to type III one increased. It suggested that respiratory infection induced by repeated MP may result in remodeling of pulmonary arterioles and are closely related to pulmonary hypertension.  相似文献   
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Acute renal artery stenosis in hydropenic dogs caused a contralateral increase in urine volume and free water clearance without change in glomerular filtration, renal blood flow, or osmolar clearance. The increase in urine volume was not dependent on the development of hypertension since it occurred in animals pretreated with trimethaphan but was dependent upon angiotensin since it was presented with angiotensin blockade with Saralasin. The effect was not caused by angiotensin inhibiting antidiuretic hormone release since the polyuria occurred in hypophysectomized animals receiving a constant infusion of 10 muU/kg per min of aqueous Pitressin. Since the rise in urine volume was associated with an increase in renal vein prostaglandin E concentration and was prevented by pretreatment with indomethacin (5 mg/kg) the results suggest that the rise in plasma angiotensin after renal artery stenosis causes an increase in contralateral prostaglandin E synthesis with resultant antagonism to antidiuretic hormone at the collecting tubule.  相似文献   
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