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51.
A comparison of the effects of left stellate ganglion stimulation (SGS) on central and aortic hemodynamics has been made in chloralose-anesthetized mongrel (M), and greyhound (GH) dogs. Measurements of aortic pressure and flow, and left ventricular pressure were made during stimulation of the decentralized left SG at different frequencies from 0 to 20 Hz. The increases in aortic pressure and flow with SGS were larger in the GH, especially for low frequencies of stimulation. Stroke volume was increased with SGS in the GH at all stimulation rates, whereas in the M it was unchanged. A greater decrease in left ventricular end-diastolic pressure with SGS was found in the GH. These results suggest that differences exist in both the intrinsic and extrinsic control of cardiac output in the greyhound dog compared to the mongrel. These differences may be in part responsible for the elevated arterial blood pressure in the greyhound compared to the mongrel. 相似文献
52.
We report the 14th case of myelolipoma of the adrenal gland. Recommendations for appropriate diagnostic and therapeutic methods are made. Myelolipoma of the adrenal gland is a rare non-functioning tumor composed of lipoid and hematopoietic elements. The most consistent complaint is abdominal pain caused by hemorrhage within the tumor. We identified an association with obesity and hypertension. Ultrasound combined with computed tomography is useful in diagnosis. With expanded use of these studies, myelolipoma will be recognized more frequently. Definitive diagnosis and treatment are accomplished by simple excision; radical surgery is unnecessary. 相似文献
53.
Extruded, puffed products prepared from potato flour combined with either partially defatted chopped beef (PDCB), mechanically deboned chicken (MDC) or chicken thigh meat (C) and coated with cheese seasoning containing three levels of chile were evaluated by instrumental and sensory methods. Expansion ratio, shear, compression and bulk density measurements indicated products prepared with C were less expanded and slightly harder than those made with MDC or PDCB. C products tended to have the lightest color. Chile pepper was the dominant flavor and aroma characteristic detected by trained sensory panelists. C puffs were generally rated more gritty/cohesive/grainy than MDC puffs by panelists. Results indicated acceptable extruded, puffed products could be 相似文献
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JC Leonard HL Drwinga CH Kim LH Toji PK Bender RA Mulivor JC Beck 《Canadian Metallurgical Quarterly》1997,46(3):530-534
The erm family of 23S rRNA adenine-N6-methyltransferases confers resistance to all macrolide-lincosamide-streptograminB (MLS) antibiotics, but not all MLS antibiotics induce synthesis of Erm methyltransferase with equal efficiency in a given organism. The induction efficiency of a test panel of MLS antibiotics was studied by using two translational attenuator-lac reporter gene fusion constructs, one based on ermSV from Streptomyces viridochromogenes NRRL 2860 and the other based on ermC from Staphylococcus aureus RN2442. Four types of responses which were correlated with the macrolide ring size were seen, as follows: group 1, both ermSV and ermC were induced by the 14-membered-ring macrolides erythromycin, lankamycin, and matromycin, as well as by the lincosamide celesticetin; group 2, neither ermSV nor ermC was induced by the 12-membered-ring macrolide methymycin or by the lincosamide lincomycin or the streptogramin type B antibiotic ostreogrycin B; group 3, ermSV was selectively induced over ermC by the 16-membered-ring macrolides carbomycin, chalcomycin, cirramycin, kitasamycin, maridomycin, and tylosin; and group 4, ermC was selectively induced over ermSV by the 14-membered-ring macrolide megalomicin. These data suggest that the leader peptide determines the specificity of induction by different classes of MLS antibiotics and that for a given attenuator, a major factor which determines whether a given macrolide induces resistance is its size. 相似文献