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21.
The effect of astaxanthin (3,3′-dihydroxy-s-carotene-4,4′-dione) on alcohol-induced morphological changes in Carassius auratus, as an experimental model, was determined. The yeast Phaffia rhodozyma was used as a source of astaxanthin. The animals were divided into three groups for 30 days: one group was treated with ethanol at a dose of 1.5% mixed in water, the second one with EtOH 1.5% and food enriched with astaxanthin from P. rhodozyma, and the third was a control group. After a sufficient experimental period, the samples were processed using light microscopy and evaluated by histomorphological and histochemical staining, and the data were supported by immunohistochemical analysis, using a wide range of antibodies, such as calbindin, vimentin and alpha-smooth muscle actin. The results show that the alcoholic damage in the kidney led to hypoxia. In contrast, the group fed with astaxanthin from P. rhodozyma showed a normal morphological picture, with better glomeruli organisation and the presence of the area of filtration. Furthermore, the immunohistochemistry has confirmed these results.  相似文献   
22.
Transplanting fetal kidney cells (FKCs) can regenerate kidney. This requires in vitro expansion in cell number to acquire enough cells for transplantation. However, FKCs may change their cellular characteristics during expansion and, thus, may not regenerate kidney tissue upon transplantation. We investigated how cell culture period affects cellular characteristics and in vivo regenerative potential of FKCs. As the passage number increased, cell growth rate and colony forming ability decreased while senescence and apoptosis increased. To examine in vivo regenerative potential, FKCs cultured through different numbers of passages were implanted into the parenchyma of kidneys of immunodeficient mice using fibrin gel for 4 wk. Histological analyses showed passage-dependent kidney tissue regeneration, and the regeneration was better when cells from lower number of passages were implanted. This result shows that in vitro culture of FKCs significantly affects the cell characteristics and in vivo tissue regenerative potential.  相似文献   
23.
There are various organic and inorganic constituents in kidney stones. Among them, calcium oxalate monohydrate (COM) is the primary inorganic constituent of kidney stones. However, the mechanisms of formation of kidney stones are not well understood. In this regard, a basic study is carried out for better understanding of nucleation, crystal growth and/or aggregation of formed COM crystals. The primary nucleation of calcium oxalate monohydrate is studied at the laboratory scale using turbidity measurements. Calcium chloride and potassium oxalate solutions are mixed and then added to a Turbidimeter tube for continuous recording of turbidity. Induction time (time to induce formation of detectable crystals) is estimated from time‐turbidity graphs. The effect of some urinary species, such as oxalate and calcium, on nucleation and crystallization characteristics of COM is determined by particle size distribution analysis, measuring weight of crystals and calculation of relative supersaturation. The classical nucleation theory is applied at high supersaturation ratios (SR) ranging from 1.6 to 2.2. The results indicate that nucleation rate increases with increasing supersaturation ratio from 0.81 × 1028 nuclei/cm3.sec at 1.6 SR, to 18.02 × 1028 nuclei/cm3.sec at 2.2 SR. On the other hand, free energy change and radius of critical nucleus are decreased as supersaturation ratio is increased. The nucleation rates are higher than those reported in literature. Such discrepancy is discussed on the bases of differences in experimental techniques. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
24.
五种补肾中成药物中微量铝分析   总被引:1,自引:0,他引:1  
用Al-CAS-OP-10分光光度法测定了五种补肾中成药中铝含量。结果表明,五种中成药中铝含量有一定的差异。本实验结果为进一步研究铝与补肾中成药的功效关系提供了有用数据。  相似文献   
25.
The natural compound curcumin has been shown to have therapeutic potential against a wide range of diseases such as cancer. Curcumin reduces cell viability of renal cell carcinoma (RCC) cells when combined with TNF-related apoptosis-inducing ligand (TRAIL), a cytokine that specifically targets cancer cells, by helping overcome TRAIL resistance. However, the therapeutic effects of curcumin are limited by its low bioavailability. Similar compounds to curcumin with higher bioavailability, such as demethoxycurcumin (DMC) and 3,5-bis(2-fluorobenzylidene)-4-piperidone (EF24), can potentially have similar anticancer effects and show a similar synergy with TRAIL, thus reducing RCC viability. This study aims to show the effects of DMC and EF24 in combination with TRAIL at reducing ACHN cell viability and ACHN cell migration. It also shows the changes in death receptor 4 (DR4) expression after treatment with these compounds individually and in combination with TRAIL, which can play a role in their mechanism of action.  相似文献   
26.
在光学实验中,用GSZF-3实验系统检测椭圆偏振光时,测得的振幅与角度在极坐标中画出的并不是椭圆,而是一个类肾脏线。本文分析了产生的原因,并提出了改进建议。  相似文献   
27.
Phase‐contrast X‐ray imaging using a crystal X‐ray interferometer can depict the fine structures of biological objects without the use of a contrast agent. To obtain higher image contrast, fixation techniques have been examined with 100% ethanol and the commonly used 10% formalin, since ethanol causes increased density differences against background due to its physical properties and greater dehydration of soft tissue. Histological comparison was also performed. A phase‐contrast X‐ray system was used, fitted with a two‐crystal X‐ray interferometer at 35 keV X‐ray energy. Fine structures, including cortex, tubules in the medulla, and the vessels of ethanol‐fixed kidney could be visualized more clearly than that of formalin‐fixed tissues. In the optical microscopic images, shrinkage of soft tissue and decreased luminal space were observed in ethanol‐fixed kidney; and this change was significantly shown in the cortex and outer stripe of the outer medulla. The ethanol fixation technique enhances image contrast by approximately 2.7–3.2 times in the cortex and the outer stripe of the outer medulla; the effect of shrinkage and the physical effect of ethanol cause an increment of approximately 78% and 22%, respectively. Thus, the ethanol‐fixation technique enables the image contrast to be enhanced in phase‐contrast X‐ray imaging.  相似文献   
28.
High-resolution magnetic resonance imaging using dedicated high-field radiofrequency micro-coils at 16.4 T (700 MHz) was investigated. Specific solenoid coils primarily using silver and copper as conductors with enamel and polyurethane coatings were built to establish which coil configuration produces the best image. Image quality was quantified using signal-to-noise ratio and signal variation over regions of interest. Benchmarking was conducted using 5-mm diameter coils, as this size is comparable to an established coil of the same size. Our 1.4-mm-diameter coils were compared directly to each other, from which we deduce performance as a function of conductor material and coating. A variety of materials and conductor coatings allowed us to choose an optimal design, which we used to image a kidney section at 10-micron resolution. We applied zero-fill extrapolation to achieve 5-micron resolution.  相似文献   
29.
Two different human stones, cystine and cholesterol from the kidney and gall bladder, were examined by time‐of‐flight secondary ion mass spectrometry using Ga+ primary ions as bombarding particles. The mass spectra of kidney stone were compared with those measured for the standard compounds, cystine and cysteine. Similar spectra were obtained for the stone and cystine. The most important identification was based on the existence of the protonated molecules [M + H]+ and deprotonated molecules [M‐H]. The presence of cystine salt was also revealed in the stone through the sodiated cystine [M + Na]+ and the associated fragments, which might be due to the patient treatment history. In the gallstone, the deprotonated molecules [M‐H]+ of cholesterol along with relatively intense characteristic fragments [M‐OH]+ were detected. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
30.
典型的三聚氰胺致幼儿肾结石红外光谱分析   总被引:2,自引:0,他引:2  
从云南省第一人民医院得到经过医学证实的典型三聚氰胺肾结石,将2 mg肾结石与200 mg KBr一同放入玛瑙研钵中研碎,进行压片。用Perkin-Elemer公司生产的spectrum 100光谱仪得到了该结石的红外光谱。吸收峰在4 000~2 000 cm-1之间有3 487,3 325, 3 162, 2 788 cm-1,在1 700~1 000 cm-1之间有1 694,1 555,1 383,1 340,1 189,1 122 cm-1,在1 000~400 cm-1之间有993,782,748,709,624,585,565,476 cm-1。结石的红外光谱经过与文献报道的饲喂含氰尿酸、三聚氰胺宠物饲料后猫的肾结石的红外光谱图及普通人肾结石的红外光谱图对比,相差很大,说明该患儿结石与宠物结石及普通人肾结石的成分相同的可能性不大;分别与三聚氰胺与尿酸的红外光谱图对比,各有50%的相似性; 将三聚氰胺、尿酸按1∶1混合后,红外光谱出现的峰在4 000~2 000 cm-1 之间有3 469,3 419,3 333,3 132,3 026,2 827 cm-1, 在1 700~1 000 cm-1之间有1 696, 1 656, 1 555, 1 489, 1 439, 1 350, 1 311, 1 198, 1 124, 1 028 cm-1, 在1 000~400 cm-1之间有993,878,814,784,745,708,619,577,475 cm-1,将其与结石的红外光谱对比,发现两张图谱有83.3%的相似性,由此得出典型三聚氰胺尿结石的主要成分为三聚氰胺和尿酸。  相似文献   
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