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81.
To evaluate the clinical usefulness of gallium 67 imaging in the detection of gastrointestinal (GI) non-Hodgkin's lymphoma (NHL) and in the assessment of the therapeutic effects, images were reviewed in 24 cases (25 lesions: stomach, 20; ileum, 2; and terminal ileum and/or cecum, 3) and were compared using barium studies and, in 16 cases, computerized tomography (CT). In all, 23 (92.0%) of the 25 lesions were detected by67Ga citrate imaging, the barium studies detected all 25, and CT detected 15 of 16 lesions (93.8%). The two lesions not identified by imaging and the one not found by CT were the smallest of all. In 2 (8.7%) of the 23 lesions positively identified by67Ga-citrate imaging, both CT and imaging revealed the extent of the tumor more accurately than did the barium studies. In all but one of the patients, a close correlation existed between the imaging results and the therapeutic effects. These data suggest that67Ga imaging is useful in conjunction with CT and barium studies for the detection of GI NHL and for the assessment of both the spatial extent of disease and the therapeutic effects, although a lack of67Ga uptake after therapy does not always indicate a good therapeutic effect.  相似文献   
82.
83.
The posterior choroidal artery supplies the lateral geniculate body, the posterior thalamus and the caudate body. Currently, a few cases of infarction in this arterial territory have been reported. This is a case of 59-year-old male, exhibiting left homonymous hemianopsia and left hemiparesis. Clinically it was impossible to make a diagnosis of infarction in this area. We were able to determine that it was a posterolateral choroidal artery infarction rather than an anterior choroidal artery infarction using 1.5 T-magnetic resonance imaging (MRI). The MRI scan clearly disclosed the areas of infarction, which included the lateral geniculate body, the posterior thalamus and the caudate nucleus body. Additionally, cerebral angiography revealed an occluded proximal portion of the right posterior cerebral artery (P2) and a patent right anterior choroidal artery. Anatomically, the areas surrounding the lateral geniculate body are supplied by both the anterior and the posterolateral choroidal arteries. However, the posterolateral choroidal artery infarctions are believed to be rare due to usual dominance of the anterior choroidal artery. Presently, with the use of MRI scanning, these areas can be easily visualized. Therefore, the posterolateral choroidal artery infarction can be diagnosed more easily. It is conceivable that more cases will be accurately diagnosed using this tool.  相似文献   
84.
85.
Acute effect of thyroid hormone on insulin secretion in rats   总被引:1,自引:0,他引:1  
To elucidate the mechanism of thyroid hormone-induced hyperinsulinemia, the acute and direct effect of thyroid hormone administration on insulin secretion was investigated in rats in vivo and in vitro. In the perfused rat pancreas, the addition of thyroxine (10 micrograms/dL) or 3,5,3'-triiodothyronine (150 ng/dL) to the perfusing medium did not affect insulin secretion. The administration of thyroxine (40 micrograms/kg, s.c.) in vivo increased the plasma insulin level from 11 +/- 2 microUnits/mL (mean +/- SD) to 30 +/- 7 microUnits/mL, while blood glucose and plasma glucagon were unchanged. This phenomenon was inhibited completely by the preadministration of oxprenolol hydrochloride (2 mg/kg, s.c.), and inhibited partly by the preadministration of metoprolol tartrate (35 mg/kg, s.c.). These results suggest that thyroid hormone induces hyperinsulinemia via beta-adrenergic stimulation in the rat.  相似文献   
86.
The mechanism by which prostacyclin acts to prevent in vivo reperfusion injury is still uncertain. This study was therefore undertaken to assess the effect of a stable prostacyclin analogue (OP 41483-alpha-CD [OP]) on oxygen-derived free radicals after heart-lung transplantation. OP was administered to the heart-lung graft through the pulmonary artery for 25 minutes encompassing the reperfusion process. Free radicals were directly measured by electron spin resonance spectroscopy. The radical intensities of pulmonary venous blood were significantly lower in the OP group than in the control group, suggesting that fewer free radicals were generated in the lungs of the OP group. The cardiac and respiratory function were better in the OP group than in the control group. The lung is the primary source of oxygen free radical attack, and the beneficial action of OP on free radical generation is almost exclusively restricted to the lung and does not apply to the heart. This result suggested that OP probably is effective in inhibiting free radical generation from the endothelium.  相似文献   
87.
A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported.  相似文献   
88.
Purpose. Poorly compressible crystals of acebutolol hydrochloride were agglomerated by the spherical crystallization technique with a two-solvent system to improve the compressibility for direct tabletting. The mechanism of improvements in static compression behaviors and tablettabilities of the spherically agglomerated crystals were investigated. Methods. The improvement of static compression behaviors of the agglomerated crystals was determined by measuring the stress relaxations and elastic recoveries of compressed powder of original and agglomerated crystals. The improved tablettability of agglomerated crystals was evaluated by the pressure transmission ratio upon compression, the ejection pressure for releasing the tablet from the die and the tablet strength, i.e., tensile strength required for breaking. Results. The higher relaxation pressure and the lower elastic recovery of the agglomerated crystals than of the original crystals were found. The pressure transmission ratio data showed that the friction pressures of the two crystals were similar during the compression period. The ejection pressure of the agglomerated crystals was lower than that of the original crystals. The tensile strength of the tablet of agglomerated crystals was greater than that of the original crystals. Conclusions. The compressibility and tablettability of the spherically agglomerated crystals prepared by the spherical crystallization technique were much improved due to their increased plastic property and reduced adhesive property compared to the original crystals.  相似文献   
89.
90.
Newborn case of maternal anti-SSA antibody-induced congenital complete heart block (CCHB) accompanying cardiomyopathy is presented. Unexpectedly, she died of ventricular tachycardia, not bradycardia, 6 days after birth. Autopsy revealed left ventricular cardiomyopathy with endocardial fibroelastosis. Thus, when evaluating fetal cardiac performance in cases of maternal anti-SSA antibody-induced CCHB, it is necessary to pay attention to myocardial attributes such as endocardial hyperplasia.  相似文献   
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