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421.
Thyroid hormones regulate energy metabolism and act on mitochondria which are an important source of free radicals in the cell. The pineal gland activates antioxidant systems via melatonin secretion and thus has a protective function in body tissues. The present study was conducted to determine the oxidative damage caused by hyperthyroidism in kidney and testis tissues of pinealectomized rats. Experimental animals were allocated to three groups: 1, control group; 2, sham pinealectomy-hyperthyroidic group; and 3, pinealectomy-hyperthyroidic group. Hyperthyroidism was induced by A 3-week intraperitoneal administration of thyroxin after sham pinealectomy or pinealectomy. Malondialdehyde (MDA) and glutathione (GSH) levels were determined in kidney and testis tissues. MDA levels of the kidney and testis tissue in the pinealectomy and hyperthyroidic groups were significantly higher than those in the sham pinealectomy-hyperthyroidic group and the control group (p < 0.001). GSH levels of both kidney and testis tissues were significantly higher in the sham-pinealectomy-hyperthyroidic group when compared to the other two groups (p < 0.001). This increase in GSH levels was more evident in the pinealectomy-hyperthyroidic group than in the control group (p < 0.001). The results of our study demonstrate that MDA and GSH levels in kidney and testis tissues increased due to hyperthyroidism and that pinealectomy made the increase in MDA levels more apparent, while decreasing GSH levels.  相似文献   
422.
423.
Coalescent-based inference of phylogenetic relationships among species takes into account gene tree incongruence due to incomplete lineage sorting, but for such methods to make sense species have to be correctly delimited. Because alternative assignments of individuals to species result in different parametric models, model selection methods can be applied to optimise model of species classification. In a Bayesian framework, Bayes factors (BF), based on marginal likelihood estimates, can be used to test a range of possible classifications for the group under study. Here, we explore BF and the Akaike Information Criterion (AIC) to discriminate between different species classifications in the flowering plant lineage Silene sect. Cryptoneurae (Caryophyllaceae). We estimated marginal likelihoods for different species classification models via the Path Sampling (PS), Stepping Stone sampling (SS), and Harmonic Mean Estimator (HME) methods implemented in BEAST. To select among alternative species classification models a posterior simulation-based analog of the AIC through Markov chain Monte Carlo analysis (AICM) was also performed. The results are compared to outcomes from the software BP&P. Our results agree with another recent study that marginal likelihood estimates from PS and SS methods are useful for comparing different species classifications, and strongly support the recognition of the newly described species S. ertekinii.  相似文献   
424.
应用VCS技术的白细胞的分类和计数   总被引:5,自引:0,他引:5  
在相当长的一段时期里,各种自动白细胞识别方法已被广泛的应用。其中有一种方法应用了VCS技术。这种方法即是本病将讨论的内容。一种专用试剂能够防止细胞受染色溶剂或细胞化学试剂的影响而改变。细胞的一些原始特性,诸如白细胞的大小,内部的物理、化学特性,以及各个细胞特殊的表面结构特性可基本保持不变。VCS方法是同时运用体积分析,传导系数和激光光散射三种技术,得到每个白细胞几乎处于原始状态的多维记录。  相似文献   
425.
Adult activity and larval development of Lophyridia concolor (Dejean) was examined in three sections of a marine beach: (1) an undisturbed section; (2) a section occasionally used by tourists; and (3) a heavily disturbed beach section. Although the activity of adult tiger beetles was similar at all three sites in spring, it diverged during the tourist season. The adults reached a high activity with two maxima on the natural beach, but it was 40% lower in the occasionally used section. The adult activity decreased abruptly without visible maxima in the tourist area. Larval activities showed similar trends. First and second instar larvae were practically absent from the heavily disturbed section. The reduced tiger beetle activity was most likely caused by disturbance and modification of habitat by the tourists. Mechanisms of this impairment are discussed. The results might be of importance for several beach inhabiting invertebrates in the Mediterranean area. Persistently high levels of tourist traffic on beaches might lead to local extirpation, as the decline of Lophyridia a. aphrodisia (Baudi), another Turkish tiger beetle species, shows.  相似文献   
426.
A series of 2-(hydrazinocarbonyl)-3-substitutedphenyl-1H-indole-5-sulfonamides possessing various 2-, 3- or 4- substituted phenyl groups with methyl-, halogeno- and methoxy- functionalities, as well as the perfluorophenyl moiety have been synthesized and evaluated as inhibitors of 13 catalytically active, mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, CA I-CA XV (of human (h) or murine (m) origin). The new compounds were ineffective inhibitors of isozymes hCA III, hCA IV, hCA VA, hCA VB, hCA VI and mCA XIII, moderate inhibitors of hCA I, hCA VII, hCA IX and mCA XV, and excellent, low-nanomolar inhibitors of hCA II and hCA XIV. The substitution pattern of the aromatic group in the 3-position of the indole ring influenced biological activity and isozyme inhibition profiles in this series of sulfonamides. Some of the best and most selective hCA XIV and mCA XV inhibitors ever reported have been identified in this study.  相似文献   
427.
During the past decade, many salivary parameters have been used to characterize disease states. Ghrelin (GAH) is recently-discovered peptide hormone secreted mainly from the stomach but also produced in a number of other tissues including salivary glands. The aim of this work was to examine the relationship between active (aGAH) and inactive (dGAH) ghrelin in the saliva and other salivary parameters in type II diabetic patients and healthy controls. Salivary parameters were assessed in a single measurement of unstimulated whole saliva from 20 obese and 20 non-obese type II diabetes patients, and in 22 healthy controls. Total protein and alpha-amylase were determined by colorimetric methods, and glucose by the glucose-oxidase method. Saliva aGAH and dGAH levels were measured using a commercial radioimmunoassay (RIA) kit. Salivary concentrations of aGAH and dGAH ghrelin were more markedly decreased in obese diabetic subjects than in the two other groups. Glucose and alpha-amylase levels were higher in diabetic subjects than in controls. Furthermore, there were correlations between GAH levels and BMI, and between GAH and blood pressure. However, there was no marked variability in saliva flow rates among the groups. These results indicate that measurement of salivary GAH and its relationship to other salivary parameters might help to provide insight into the role of ghrelin in diabetes.  相似文献   
428.
Denys-Drash syndrome (DDS) is a rare disorder characterized by glomerulopathy, genital abnormalities and predisposition to Wilms' tumor. It is associated with constitutional Wilms'tumor suppressor 1 (WT1) gene mutations, in which the majority being missense mutations in the zinc-finger region. Here, we present a newborn with DDS, associated with a novel heterozygous missense mutation, p.Asp396His, on exon 9 of WT1.  相似文献   
429.
Menaquinone-7 (MK-7), a subtype of vitamin K, has received a significant attention due to its effect on improving bone and cardiovascular health. Current fermentation strategies, which involve static fermentation without aeration or agitation, are associated with low productivity and scale-up issues and hardly justify the commercial production needs of this vitamin. Previous studies indicate that static fermentation is associated with pellicle and biofilm formations, which are critical for MK-7 secretion while posing significant operational issues. Therefore, the present study is undertaken to evaluate the possibility of using a biofilm reactor as a new strategy for MK-7 fermentation. Bacillus species, namely, Bacillus subtilis natto, Bacillus licheniformis, and Bacillus amyloliquifaciens as well as plastic composite, supports (PCS) were investigated in terms of MK-7 production and biofilm formation. Results show the possibility of using a biofilm reactor for MK-7 biosynthesis. Bacillus subtilis natto and soybean flour yeast extract PCS in glucose medium were found as the most potent combination for production of MK-7 as high as 35.5 mg/L, which includes both intracellular and extracellular MK-7.  相似文献   
430.
Behcet's disease (BD) was originally described by Turkish dermatologist, Hulusi Behcet in 1937. BD is an inflammatory disorder of unknown cause, characterized by recurrent oral aphthous ulcers, genital ulcers, uveitis, and skin lesions. All these common manifestations are self-limiting except for ocular attacks. The aims of this study were to assess whether BD patients have more genotoxicity than healthy controls and whether colchicine (COL) treated BD patients are different from those not using COL in terms of genotoxicity. A few dozens of methods have been developed and used for the assessment of genotoxicity. The most popular method is based on single cell gel electrophoresis (COMET assay) in alkaline condition. After electrophoresis, captured images are subjected to digital image analysis to find the values for percent tail DNA from comet assay parameters consistent with genotoxicity. COMET assay was performed in isolated lymphocytes from 42 COL treated Behcet's disease patients, 9 BD patients not using COL, and 36 healthy controls. In the COL-BD patients and non-COL-BD patients, the mean age (range 14-56 years) and mean disease duration (range 0.5-24 years) did not differ between the two groups. We found statistical differences in percent tail DNA between BD and the healthy controls (13.38+/-9.58 versus 2.77+/-1.45, P<0.0001). No difference in percent tail DNA was observed between users and non-users of COL, whereas it was more different in inactive BD patients than active ones (19.75+/-10.49 versus 11.83+/-8.79, P<0.05, respectively). Genotoxicity, as assessed by COMET assay, is increased in BD patients. These results suggest that genotoxicity is associated with BD itself rather than COL use.  相似文献   
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