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71.
The results of eight soundings conducted from sites at high latitude during the summers of 1963 through 1965 suggest that a relation exists between the winds at the mesopause and the occurrence of noctilucent clouds. These measurements indicate that situations in which noctilucent clouds are present are associated with lower wind speeds than is the case where there are no clouds. 相似文献
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Transpiration from a wellwatered sudangrass stand in a highly evaporative environment (Tempe, Arizona, in July) can be considerably increased by exposing a small plot of about I square meter to radiative and convective heat input. Thus, the transpiration of sudangrass in a full stand appears not to be determined by any physiological factor during any time of the day. 相似文献
75.
Pepsin: hydrochloric acid digestion and histological examination of the myocardium of 51 hearts from five to nine month-old lambs from the southern half of the North Island, showed that 47 (92%) were infected with microscopic sarcocysts that are presumed to be dog-derived. Of 157 sarcocysts detected histologically, 32 corresponded morphologically with Sarcocystis ovicanis and 120 with Sarcocystis tenella (Syn. S. arieticanis). The remainder could not be identified as to type. 相似文献
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Dirikolu L Lehner AF Hughes C Karpiesiuk W Camargo FC Harkins JD Woods WE Bosken JM Boyles J Troppmann A Fisher M Tobin T 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(4):350-363
Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (<1.010) and serum furosemide concentrations (>100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine the pharmacokinetic parameters of furosemide in equine serum samples and its effects on urinary SG after IV administration (250 mg) to 10 horses. Pharmacokinetic analysis showed that serum concentrations of furosemide were well described by a two-compartmental open model. Based on results in this study, it is very unlikely for horses to have serum furosemide concentrations greater than 100 ng/ml or urine SG less than 1.010 at 4 hours after administration (250 mg IV). However, it should be remembered that urine SG is a highly variable measurement in horses, and even without furosemide administration, some horses might naturally have urine SG values less than 1.010. 相似文献
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Kock WE 《Science (New York, N.Y.)》1971,174(4010):674-675
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