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81.
胆碱能M受体拮抗剂:2α-(2',2'-二取代基-2'-羟基乙氧基)托品烷光学异构体合成王林,恽榴红,张其楷(军事医学科学院毒物药物研究所,北京100850)目前临床所用托品类抗胆碱药一般为3位取代托品酯类衍生物,这类药物作用较广泛,但选择性不高。A...  相似文献   
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用涂圈压电石英晶体频移一中和萃取法测定枸橼酸维静宁(咳必清),检出限0.02μg,在0.05~1.6μg范围内呈线性,相关系数0.999,变异系数为2.3%。与经典的中和萃取法相比,本法具有明显的优越性。  相似文献   
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L-carnitine is a quaternary amine that is essential for the normal oxidation of long-chain fatty acids by mitochondria. It is known that L-carnitine and its derivatives prevent the formation of reactive oxygen species, scavenge free radicals and protect cells from peroxidative stress. Oxygen-derived free radicals and lipid peroxidation products play a critical role in the pathogenesis of ethanol-induced gastric mucosal injury. The aim of the present study was to determine the effect of L-carnitine on lipid peroxidation induced by ethanol in the rat stomach. In our study, gastric mucosal injury was induced by the intragastric administration of 1 ml of absolute ethanol. Test compounds were given to rats by gavage 30 min before the ethanol administration. The animals were killed 60 min after the administration of ethanol. The stomach of each animal was removed. Mucosal damage was evaluated by macroscopic examination, histological analysis and by measurement of lipid peroxidation and glutathione activity. The intragastric administration of ethanol induced hyperemia and hemorrhagic erosions in the rat stomachs. L-carnitine significantly prevented gastric ulcerogenesis induced by ethanol and decreased the ulcer index. Plasma and gastric lipid peroxidation that was increased significantly by ethanol was decreased after treatment with L-carnitine. Ethanol treatment decreased significantly the gastric glutathione levels, and pretreatment with L-carnitine increased them significantly. Based on these data, the beneficial effects of L-carnitine on ethanol-induced gastric mucosal injury may be attributed to its antiperoxidative effects.  相似文献   
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Purpose  

Cardiac resynchronization therapy (CRT) is a treatment option for selected heart failure patients. In this study, the aim was to evaluate the usefulness of noninvasive cardiac vein imaging using multidetector computed tomography (MDCT) angiography before CRT.  相似文献   
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Objective

The aim of our study was to investigate the value of choline in the discrimination of benign and malignant soft tissue and bone tumors.

Materials and methods

The study group consisted of thirty subjects with bone or soft tissue tumors larger than 1.5 cm in diameter. The experiments were performed in a 1.5 T MR scanner. Coils were selected according to specific locations. A single-voxel MRS was performed for three different TE (time to echo) (31, 136, 272 ms). The volume of interest was positioned on the brightest enhancement. The presence of a cholin peak on at least 2 of these spectrums was considered as the marker of malignancy. The sensitivity, specificity and accuracy of the MRS in the detection and diagnosis of malignant lesions were calculated. The reproducibility of MRS and histopathological results were tested with kappa statistics.

Results

Histopathologically, 18 (60%) of the lesions were classed as malignant whereas 12 (40%) were classed as benign. With MRS, 15 (50%) of these lesions were classed as malignant and 15 (50%) as benign. Two patients who were found spectroscopically to have malignant tumors were shown histopathologically to have benign types. Five patients with an MRS showing a benign type were classed with malignant types in histopathological examinations. MRS had a sensitivity rate of 72.2%, specificity of 83.3%, and an accuracy rate of 76.6% in detecting malignant bone and soft tissue tumors. The interrater reliability of both techniques had a kappa value of 0.533.

Conclusions

MRS may help in the differentiation of benign and malignant soft tissue and bone tumors.  相似文献   
89.
Poland syndrome was first described in 1840 by Alfred Poland while still a medical student and the other components of the syndrome were described at London Guy's Hospital following the dissection of a cadaver's hand, which had hypoplasia and syndactyly. The incidence of Poland syndrome has been reported to be 1 in 30,000 live births. In the present case report, two Poland syndrome patients with ipsilateral hypomastia and a reduction in the axillary/pectoral hairs diagnosed during adulthood are presented; one patient was affected on the left side and had widespread cafe au lait spots, and the other patient had respiratory dysfunction due to multiple rib anomalies.  相似文献   
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