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21.
The inclusion of phloridzin into beta-cyclodextrin was studied as a model of molecular recognition in membranes. Effects on 1H NMR spectra and NOE correlational peaks between phloridzin and beta-cyclodextrin were observed in the complex. Strong NOEs were observed between hydrogens of a phenol group in phloridzin and beta-cyclodextrin. The three-dimensional structure of the inclusion complex between phloridzin and beta-cyclodextrin was simulated with distance constraints estimated by the intensity of NOE peaks using the DADAS90 programs. Two inclusion possibilities were suggested-the large rim of beta-cyclodextrin as an entrance of the inclusion and the small rim of beta-cyclodextrin as the entrance. In both cases, the phenol group of phloridzin was included in the hydrophobic space of beta-cyclodextrin.  相似文献   
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The influence of grazing by water buffalo (Bubalas bufalis) and cattle (Bos taurus) was estimated for vegetation inside and outside cages in a saline area at Khon Kaen, Northeast Thailand. The home range of water buffalo and cattle shifted in response to the period of rice cultivation: during the rice-growing season these animals grazed on roadsides and abandoned places such as the study area; after rice harvest they grazed mainly rice stubble on the paddy. The vegetation in the study area was divided into three types: 1) dominated by the annual grassesChloris barbata andIschaemum rugosum; vegetational cover and plant height in the cage increase due to the increase of these grasses; 2) thorny shrub patch ofMaytenus mekongensis; other species in this patch almost died a year after experimental elimination of this shrub; this salt-tolerant shrub not only protected the co-existing species from grazing, but also suppressed salt accumulation; 3) almost pure stand ofPanicum repens; livestock preferred this perennial grass over others. Electrical conductivity (EC) of surface soil did not increase under the vegetation protected from grazing. Litter and other organic matter in the soil suppressed the upward movement of brine. Grazing led to an increase of bare ground where NaCl accumulated, and modified the heterogeneity of vegetation, which was reflected in the degree of salt accumulation.  相似文献   
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The effects of U-61,431F, ciprostene, a stable prostacyclin analogue, were examined on the proliferation of cultured quiescent bovine aortic endothelial cells (EC) and smooth muscle cells (SMC). After stimulation with 5% fetal calf serum, U-61,431F suppressed both the DNA synthesis and proliferation of SMC dose-dependently at the concentration of 3-100 microM, but had no effect on either of them in EC at a concentration of up to 30 microM. The inhibitory effect on DNA synthesis was greater in SMC than in EC at 3-50 microM. When SMC were stimulated with platelet-derived growth factor (PDGF) for 2 hrs followed by a 22-hr incubation with insulin, U-61,431F (1-50 microM) administered at the time of PDGF stimulation did not inhibit DNA synthesis. SMC initiated and terminated DNA synthesis at about 15-18 h and 24 h after stimulation with serum, respectively. Inhibition of DNA synthesis in serum-stimulated SMC as a function of the addition time of U-61,431F reduced at 3-12 h after the stimulation. U-61,431F raised the cyclic AMP (cAMP) content in SMC. Moreover, a phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, and a more specific cAMP phosphodiesterase inhibitor, Ro 20-1724, augmented the inhibition of DNA synthesis in SMC concomitant with further elevation of cAMP level. These results suggest that U-61,431F inhibits DNA synthesis of SMC acting in the progression stage rather than in the competence stage, with little antiproliferative effect on EC. cAMP may play an important role in its antiproliferative action in SMC.  相似文献   
25.
Immunohistochemical distribution of laminin gamma2 chain, a subunit of the basement membrane protein laminin-5, was examined in 19 cases of human embryos and foetuses ranging from 4 to 25 weeks of gestation. Laminin gamma2 was first detected in the basement membranes underlying ectodermal epithelial tissues, such as the skin and tooth, as early as 5-6 weeks of gestation. Between 6-7 and 12-13 weeks, laminin gamma2 was detected in the basement membranes of various endodermal epithelial tissues, such as the bronchus, oesophagus, stomach, intestines, urinary bladder, gallbladder and hepatopancreatic duct. The deposition of laminin gamma2 in basement membrane was associated with the process of morphogenesis. In the small intestine, laminin gamma2 first appeared in the basement membrane of the primitive short villi, and its level gradually increased in the villus region but decreased in the cryptic region during the maturation of the organ. In addition, non-basement membrane immunoreactivity for laminin gamma2 was detected in some mesoderm-derived tissues, such as the cartilage and skeletal and smooth muscle fibres. These results suggest a common role of laminin-5 and some specific roles of its gamma2 chain in the morphogenesis of human tissues.  相似文献   
26.
Severe left ventricular volume overloading causes myocardial and cellular contractile dysfunction. Whether this is also true for severe right ventricular volume overloading was unknown. We therefore created severe tricuspid regurgitation percutaneously in seven dogs and then observed them for 3.5-4.0 yr. All five surviving operated dogs had severe tricuspid regurgitation and right heart failure, including massive ascites, but they did not have left heart failure. Right ventricular cardiocytes were isolated from these and from normal dogs, and sarcomere mechanics were assessed via laser diffraction. Right ventricular cardiocytes from the tricuspid regurgitation dogs were 20% longer than control cells, but neither the extent (0.171 +/- 0.005 microm) nor the velocity (2.92 +/- 0.12 microm/s) of sarcomere shortening differed from controls (0.179 +/- 0.005 microm and 3.09 +/- 0.11 microm/s, respectively). Thus, despite massive tricuspid regurgitation causing overt right heart failure, intrinsic right ventricular contractile function was normal. This finding for the severely volume-overloaded right ventricle stands in distinct contrast to our finding for the left ventricle severely volume overloaded by mitral regurgitation, wherein intrinsic contractile function is depressed.  相似文献   
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Background & Aims

The amount of drug-loaded lipiodol in an HCC tumor post-transarterial chemoembolization (TACE) correlates with the risk of local tumor recurrence. Lipiodol enhancement of a tumor on conventional CT, measured in Hounsfield units (HU), can predict tumor response. Here we investigate whether cone-beam CT (CBCT) can also be used to predict tumor response, providing the benefit of being able to optimize the patient’s treatment plan intra-procedurally.

Methods

A total of 82 HCC nodules (82 patients), ≤5 cm in diameter, were treated with balloon-occluded TACE using miriplatin between December 2013 and November 2014. For each patient, both CBCT and conventional CT images were obtained post-TACE. The degree of correlation between CBCT and conventional CT was determined by comparing identical regions of interest for each imaging modality using pixel values.

Results

The pixel values from conventional CT and CBCT were highly correlated, with a Pearson correlation coefficient of 0.912 (p<0.001). The location of the nodules within the liver did not affect the results; the correlation coefficient was 0.891 (p<0.001) for the left lobe and 0.926 (p<0.001) for the right lobe. The mean pixel value for conventional CT was 439 ± 279 HU, and the mean pixel value for CBCT was 416 ± 311 HU.

Conclusions

CBCT may be used as a substitute for conventional CT to quantitatively evaluate the amount of drug-loaded lipiodol within an HCC nodule and, hence, the efficacy of TACE treatment. The major benefit of using CBCT is the ability to predict the likelihood of local recurrence intra-procedurally, enabling subsequent treatment optimization.  相似文献   
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Neurovascular degeneration contributes to the pathogenesis of Alzheimer's disease (AD). Because erythropoietin (EPO) promotes endothelial regeneration, we investigated the therapeutic effects of EPO in animal models of AD. In aged Tg2576 mice, EPO receptors (EPORs) were expressed in the cortex and hippocampus. Tg2576 mice were treated with daily injection of EPO (5000 IU/kg/day) for 5 days. At 14 days, EPO improved contextual memory as measured by fear-conditioning test. EPO enhanced endothelial proliferation and the level of synaptophysin expression in the brain. EPO also increased capillary density, and decreased the level of the receptor for advanced glycation endproducts (RAGE) in the brain, while decreasing in the amount of amyloid plaque and amyloid-β (Aβ). In cultured human endothelial cells, EPO enhanced angiogenesis and suppressed the expression of the RAGE. These results show that EPO improves memory and ameliorates endothelial degeneration induced by Aβ in AD models. This pre-clinical evidence suggests that EPO may be useful for the treatment of AD.  相似文献   
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