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101.
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Gatenby  RA; Moldofsky  PJ; Weiner  LM 《Radiology》1988,166(3):757-759
Tumor oxygen levels were measured with an electrode in 13 patients with colon carcinoma metastases. These measurements were correlated with images obtained with radiolabeled monoclonal antibody 1083-17-1A. Only those tumors or tumor regions with a mean PO2 of 16 mm Hg or greater were successfully imaged. Tumors and tumor regions with a mean PO2 of less than 16 mm Hg were not imaged, even when the presence of antigen was confirmed with biopsy. These data suggest that physiologic factors other than antigen expression may affect antibody uptake.  相似文献   
103.
张志荣  廖工铁  叶利民 《药学学报》1995,30(11):843-847
建立了血浆中米托蒽醌的柱切换高效液相色谱测定法,测定和比较了米托蒽醌溶液型注射剂和毫微粒冻干静脉注射剂在家兔体内的血药曲线,并研究比较了二者的药代动力学参数。米托恩醌毫微粒冻干注射剂使米托蒽醌在血中浓度大为降低,血中分布容积增大了近5倍,体内平均驻留时间延长了2倍多。表明米托蒽醌毫微粒有明显的体内长效作用,结合其体内分布试验研究结果,表明其具有明显肝靶向分布作用。  相似文献   
104.
Recently, it has been demonstrated that Ca2+ entrance into the neuronal cytoplasm can occur upon the activation of 3 different types of specific voltage-dependent channels which can be characterized according to the following criteria: (1) voltage threshold for activation; (2) tendency to inactivation; (3) bivalent cation permeability; and (4) drug sensitivity. In this study we investigated, in tuberoinfundibular dopaminergic (TIDA) hypothalamic neurons, the biochemical and pharmacological properties of Ca2+ channels, by comparing the effects of high extracellular concentrations of Ba2+ and Ca2+ ions on [3H]dopamine (DA) release from TIDA neurons. The results obtained show that extracellular Ba2+ ion concentrations dose-dependently (10-20 mM) stimulated [3H]DA release from superfused TIDA neurons and that this effect was prevented by Co2+ ions (2 mM). In addition, superfusion of TIDA neurons with a concentration of Ca2+ ions equimolar to that of Ba2+ ions (20 mM) failed to modify [3H]DA release. The fact that tetraethylammonium (10 mM), a blocker of K+ currents in excitable cells, did not mimick the stimulatory action of Ba2+ ions on [3H]DA release, seems to exclude that the effect of Ba2+ ions was dependent on the inhibition of K+ channels in TIDA neurons. The omission of Ca2+ ions from the extracellular medium did not prevent the stimulatory effect on [3H]DA release elicited by elevated concentrations of Ba2+ ions, but rather reinforced this effect. Finally, nitrendipine (50 microM) did not modify the stimulatory effect of high extracellular Ba2+ ions on [3H]DA release from TIDA neurons.  相似文献   
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本文提出了差示一线性组合导数光谱法用于测定混合组分体系的基本原理和实验方法。并试用本法消除了扑尔敏、溴化丙胺太林、灵芝粉及附加剂之间的相互干扰,从而分别测定了扑咳灵片巾扑尔敏和溴化丙胺太林的含量,其平均回收率分别为100.2±1.49%(CV)和99.89±1.03%(CV)。其精密度、准确度均好。  相似文献   
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To determine the value of sonography in the emergent evaluation of suspected leaking abdominal aortic aneurysms, the authors examined 60 patients in the emergency department using sonography and a protocol involving advance radio notification from the ambulance; arrival of sonographic personnel and equipment in the triage room before patient arrival; and, during other triage activities, rapid sonographic evaluation of the aorta for aneurysm and of the paraaortic region for extraluminal blood. Sonographic findings were correlated with surgical results and clinical outcome. When performed under these circumstances, sonography was accurate in demonstrating presence or absence of aneurysm (98%), but its sensitivity for extraluminal blood was poor (4%). A combination of sonographic confirmation of aneurysm, abdominal pain, and unstable hemodynamic condition resulted in the correct decision to perform emergent surgery in 21 of 22 patients (95%). An abbreviated sonographic examination done in the emergency room can provide accurate, useful information about the presence of aneurysm; this procedure does not significantly delay triage of these patients.  相似文献   
110.
HaywardRW; Zatz  LM 《Radiology》1975,117(2):475-478
The thinnest pair of slices provided by the EMI scanner is 8 mm, producing an overlap of 6 mm. Resolution is reduced by averaging the density of structures throughout the thickness of the slice. The authors described special collimators which provide thinner slices with no overlap and thereby improve the quality of orbital scans.  相似文献   
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