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991.
Inhibitory activity of diacylglycerol acyltransferase by tanshinones from the root of Salvia miltiorrhiza 总被引:4,自引:0,他引:4
Ko JS Ryu SY Kim YS Chung MY Kang JS Rho MC Lee HS Kim YK 《Archives of pharmacal research》2002,25(4):446-448
The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with IC50 values of 10.5 microg/ml and 11.1 microg/ml. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition (IC50 value: > 250 microg/ml). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity. 相似文献
992.
Non ionic, amphipathic molecules form vesicles and this property correlates with the disruption of membranes. In the present studies, high mM concentrations of aliphatic alcohols, 1-O-hexyldiglycerol (HDG) and 1-O-heptyltriglycerol (HTG), are shown to cause enhanced drug transport into brain via disruption of the blood-brain barrier (BBB) in vivo, as determined with an internal carotid artery perfusion method. The intravenous administration of comparable concentrations of HDG or HTG caused no increase in BBB transport of drug. The enhanced transport of drug showed a dependency on molecular weight as 45 mM HTG increased the transport of sucrose, 360 Da, but did not increase the transport of arginine vasopressin (AVP), 1084 Da, although AVP transport across the BBB was increased by 80 mM HDG or HTG. Quasielastic light scattering measurements provided evidence for the formation of vesicular structures in aqueous solutions containing high mM concentrations of the HDG or HTG. In summary, these studies demonstrate BBB disruption following the internal carotid arterial infusion of high mM concentrations of membrane active alkyl glycerols. 相似文献
993.
Jeong TC Lee ES Chae W Koh WS Kang BH Han SS 《Journal of toxicology and environmental health. Part A》2002,65(5-6):383-394
Immunotoxic effects of 2-bromopropane were investigated in male Sprague-Dawley rats. The rats were treated orally daily with 2-bromopropane at 100, 330, or 1000 mg/kg for 28 consecutive days. Four days before necropsy, the rats were immunized intravenously with sheep red blood cells (SRBCs). The body and thymus weights were significantly reduced by treatment with 2-bromopropane at the highest dose. In addition, the numbers of splenic and thymic cells were decreased by 2-bromopropane. In hematology, the numbers of white blood cells, red blood cells, and platelets were significantly reduced. Among the serum clinical parameters, the levels of chloride ion were significantly increased by 2-bromopropane. The antibody response to SRBCs was significantly suppressed at the highest dose. With immunized animals, immunophenotyping of splenic and thymic cells was performed to investigate the changes of the number of macrophages, B cells, and T cells in spleen and the number of CD4+ and CD8+ cells in thymus. The numbers of most cell types were significantly decreased in the spleen when animals were treated with 2-bromopropane at 1,000 mg/kg. Likewise, all cell types of thymus were significantly decreased by 2-bromopropane. The present results suggest that 2-bromopropane may have an immunotoxic potential in male Sprague-Dawley rats when the rats are exposed for 28 d. 相似文献
994.
Lee MS Huh HJ Kim BG Ryu H Lee HS Kim JM Chung HT 《The American journal of Chinese medicine》2002,30(4):463-470
This study investigates changes in autonomic nervous function through Qi-training. The power spectrum of heart rate variability (HRV) was examined in 20 sedentary healthy subjects and 20 Qi-trainees. It was found that Qi-training in healthy young subjects during controlled respiration increases the high frequency (HF) power and decreases the low frequency/high frequency (LF/HF) power ratio of HRV. These results support the hypothesis that Qi-training increases cardiac parasympathetic tone. In addition, Qi-trainees were found to have higher parasympathetic heart modulation compared with their age-matched, sedentary counterparts. This augmented HRV in Qi-trainees provides further support for long-term Qi-training as a possible non-pharmacological cardio-protective maneuver. In conclusion, Qi-training may stabilize the autonomic nervous system by modulating the parasympathetic nervous system. 相似文献
995.
OBJECTIVES: To describe the diffusion-weighted MR (DWI) findings of isolated angiitis of the central nervous system (IACNS) and narrow the differential diagnosis. METHODS: The DWI findings of two IACNS patients. Apparent diffusion coefficient (ADC) values were measured in the abnormal lesions, and DWI and T2-weighted MR images were visually inspected. RESULTS: IACNS was diagnosed based on clinical history, MR findings and cerebral angiographic findings. DWI showed hyperintense lesions with heterogeneous ADC values (287-1359 x 10(-6) mm2/s), which indicate the coexistence of cytotoxic and vasogenic oedema. CONCLUSIONS: The findings suggest that the various stages of inflammatory process with ischaemia might exist in IACNS and allow a differentiation from the usual arterial ischaemic infarction. DWI with ADC map can be a useful non-invasive diagnostic test increasing specificity in the diagnosis of IACNS, combined with conventional MRI and cerebral angiography. 相似文献
996.
Kim HJ Kim JE Ha M Kang SS Kim JT Park IS Paek SH Jung HW Kim DG Cho GJ Choi WS 《Brain research》2003,978(1-2):245-249
In this study we found the expression of steroidogenic acute regulatory protein (StAR) mRNA and protein in both the normal human brain and intracranial tumors, using RT-PCR and immunohistochemistry. StAR mRNA is expressed at a very low level in the white matter of the normal human brain, but in tumoral tissues StAR mRNA was specifically expressed in oligodendrogliomas and malignant glial tumors. StAR-positive cells were also detected in the normal human brains and gliomas; its frequency and density were higher in glioma tissue. These findings suggest that StAR expression might be correlated with the growth of glial tumors. 相似文献
997.
Described is a patient with hydrocephalus and a gait disorder with associated prolonged fever and hyponatremia. The authors made a diagnosis of normal pressure hydrocephalus (NPH) and performed a ventriculoperitoneal shunt, which improved the gait disturbance, accompanied by resolution of the fever and hyponatremia. 相似文献
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We report a case of metastatic hepatocellular carcinoma of gingiva mimicking pyogenic granuloma. To our knowledge, no such reports have been published in the literature of dermatology. Gingival metastatic lesions are of interest both because they are easily mistaken for several benign lesions and because they may be the first sign of an undiscovered malignancy. 相似文献