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81.
82.
 平滑肌细胞的数量、表型以及在间质细胞中所占的比例在前列腺间质增生的发生和发展中占有重要的地位.获得纯的平滑肌细胞和成纤维细胞,研究它们基因表达的差异,有助于进一步揭示前列腺增生的分子病因学.构建不同长度的 SM 22启动子,测定荧光素酶活性.采用了基于启动子特异性激活红绿色荧光蛋白表达结合流式细胞分选的策略,体外分离纯的平滑肌细胞和成纤维细胞.启动子活性实验结果表明,1 396 bp的人SM22启动子具有平滑肌细胞特异性和较高的相对活性.构建了红绿荧光蛋白的表达载体pDual-color,在此载体中,RFP的表达受1 396bp的SM22启动子调控,GFP的组成型表达受CMV启动子控制.用流式细胞仪分选GFP+/RFP+和GFP+/RFP-细胞,提取总RNA,进行实时定量RT-PCR.结果显示,在分选获得的GFP+/RFP+细胞比GFP+/RFP-细胞的SM22和SMMHC表达水平高10倍以上.提示,基于启动子特异性可以在体外分离纯的平滑肌细胞和成纤维细胞.  相似文献   
83.
In this study, the preliminary analyses were conducted of enzymatic activities of uridine phosphorylase (UP) and thymidine phosphorylase (TP) in normal tissues and cancer tissues of the uterine cervix. The study was performed on 27 patients of cervical cancer, treated first in our hospital. Normal cervical tissues obtained from 15 patients undergoing hysterectomy for benign diseases were used as controls. The supernatant of the homogenated cervical tissues and the stroma (5-FU and ribose-1-P or deoxyribose-1-P) were analyzed by high performance liquid chromatography, and then the UP and TP activities calculated. TP activity was significantly greater than UP activity (P < 0.0001). Both UP and TP showed significantly greater activity in cancer tissues than in normal tissues (P < 0.0001). In the TP activity of the cancer tissues, there was no significant difference among the histological types, while the TP activity tended to be significantly higher in the cases with lymph node metastasis. These results showed that the TP-mediated route seemed important as the 5FU metabolic pathway in the uterine cervical tissues, and TP enzymatic activity might be associated with lymph node metastasis.  相似文献   
84.
Inflammation is a common finding in benign prostatic hyperplasia (BPH). The phytotherapeutic agent eviprostat is a popular treatment for BPH in Japan and Germany. This agent consists of five components; four are extracted from Chimaphila umbellata, Populus tremula, Pulsatilla pratensis and Equisetum arvense (coded as EVI-1, EVI-2, EVI-3 and EVI-4, respectively) and the fifth is germ oil from Triticum aestivum (coded as EVI-5). In this study, the effects of each component on the reactive oxygen species (ROS), superoxide anion (O2-) and hydroxyl radical (OH*) generated in cell-free systems and human neutrophils, and on carrageenin-induced paw edema in rats were investigated. EVI-1, EVI-2 and EVI-4 suppressed the O2- levels in the xanthine/xanthine oxidase system, and EVI-1, EVI-2, EVI-3 and EVI-4 abolished the OH* produced in a Fenton-type reaction system, so that EVI-1, EVI-2 and EVI-4 possessed inhibitory action with respect to both O2- and OH*. EVI-1, EVI-2 and EVI-4 also reduced ROS levels in phorbol myristate acetate-stimulated neutrophils. The paw swelling was inhibited by a mixture of EVI-1, EVI-2, EVI-3, EVI-4 and EVI-5 (a mixture which is equivalent to eviprostat) or by a mixture of EVI-1, EVI-2 and EVI-4, even though each component alone did not significantly inhibit the swelling. These findings suggest that the suppression of ROS by EVI-1, EVI-2 and EVI-4 may partly contribute to the anti-inflammatory action of eviprostat, and this action may be implicated in its therapeutic effect on BPH.  相似文献   
85.
Ligneous membranitis (LM) is a rare chronic inflammatory condition of the mucous membranes associated with plasminogen (encoded by PLG) deficiency in affected humans and dogs. In human, the condition is genetic in nature with numerous mutations and polymorphisms in PLG identified in affected individuals and related family members. The condition is uncommonly reported in dogs and, to date, no genetic studies have been performed. We identified related Scottish Terriers (littermates) with severe LM and unaffected relatives (sire, dam and a sibling from a previous litter). Plasma plasminogen activity was below normal in one affected dog but within normal reference intervals for the other. Sequencing of PLG from the affected dogs revealed a homozygous A>T single nucleotide polymorphism in an intron donor site (c.1256+2T>A). The related, unaffected dogs displayed heterozygous alleles at this position (c.1256+2T/A), whereas no mutation was detected in unaffected, non‐related control dogs. This is the first report to identify gene polymorphisms associated with LM in dogs.  相似文献   
86.
The visual and oculomotor systems in the brain have been studied extensively in the primate. Together, they can be regarded as a single brain system that underlies active vision—the normal vision that begins with visual processing in the retina and extends through the brain to the generation of eye movement by the brainstem. The system is probably one of the most thoroughly studied brain systems in the primate, and it offers an ideal opportunity to evaluate the advantages and disadvantages of the series of perturbation techniques that have been used to study it. The perturbations have been critical in moving from correlations between neuronal activity and behaviour closer to a causal relation between neuronal activity and behaviour. The same perturbation techniques have also been used to tease out neuronal circuits that are related to active vision that in turn are driving behaviour. The evolution of perturbation techniques includes ablation of both cortical and subcortical targets, punctate chemical lesions, reversible inactivations, electrical stimulation, and finally the expanding optogenetic techniques. The evolution of perturbation techniques has supported progressively stronger conclusions about what neuronal circuits in the brain underlie active vision and how the circuits themselves might be organized.  相似文献   
87.
Rising levels of ultraviolet radiation (UVR) secondary to ozone depletion are an issue of concern for public health. Skin cancers and intraepidermal dysplasia are increasingly observed in individuals that undergo chronic or excessive sun exposure. Such alterations of skin integrity and function are well established for humans and laboratory animals, but remain unexplored for mammalian wildlife. However, effects are unlikely to be negligible, particularly for species such as whales, whose anatomical or life-history traits force them to experience continuous sun exposure. We conducted photographic and histological surveys of three seasonally sympatric whale species to investigate sunburn and photoprotection. We find that lesions commonly associated with acute severe sun damage in humans are widespread and that individuals with fewer melanocytes have more lesions and less apoptotic cells. This suggests that the pathways used to limit and resolve UVR-induced damage in humans are shared by whales and that darker pigmentation is advantageous to them. Furthermore, lesions increased significantly in time, as would be expected under increasing UV irradiance. Apoptosis and melanocyte proliferation mirror this trend, suggesting that whales are capable of quick photoprotective responses. We conclude that the thinning ozone layer may pose a risk to the health of whales and other vulnerable wildlife.  相似文献   
88.
宫腔镜联合B超诊断异常子宫出血124例临床分析   总被引:1,自引:0,他引:1  
目的:探讨宫腔镜联合B超在诊治异常子宫出血的临床价值。方法:对124例异常子宫出血的病例进行回顾性分析,所有患者作B超及宫腔镜检查,宫腔内切除物或刮出物均送病理检查。结果:124例患者经病理检查确诊为子宫内膜息肉84例(67.7%),合并宫颈息肉10例;子宫内膜增生症16例(12.9%),其中单纯性增生12例,复杂性增生4例;子宫内膜不典型增生1例(0.8%);子宫粘膜下肌瘤12例(9.7%);子宫内膜样腺癌6例(4.8%);子宫内膜炎3例(2.4%);胚物残留2例(1.6%)。结论:宫腔镜联合B超检查是诊断异常子宫出血最好的方法.  相似文献   
89.
目的:探讨在B超引导下子宫内膜消融术治疗更年期功血的效果。方法:扩张宫颈至6.5号,吸宫,在B超监视下由子宫右前壁始向外刮凝,依次顺时针方向刮凝宫腔2周。结果:治愈31例(60.8%),有效19例(37.3%),好转1例(1.9%),无效0例。结论:电凝刀子宫内膜消融术与其他更年期功血治疗方法相比,消融的范围及深度由B超监视,安全性高,创伤小,不开刀,恢复快,并且治愈率高,更容易在临床上推广。  相似文献   
90.
OBJECTIVE: This study investigates the role of liquid-based cytology with ThinPrep technique, in the detection of endometrial lesions, using direct endometrial sampling from postmenopausal women with the Endogyn endometrial device. METHODS: It was performed on 491 postmenopausal women referred to our clinic for abnormal bleeding or other symptoms and/or a thickness of endometrium >5 mm on ultrasound. Endometrial sampling, dilatation and curettage (D&C) and hysterectomy were performed on all patients. For the diagnosis, the WHO classification scheme was used. RESULTS: According to our findings a sensitivity of 98.08%, specificity of 100%, positive predictive value of 100%, negative predictive value of 100% and overall accuracy of 98.98% were observed in both endometrial sampling and in D&C. CONCLUSIONS: Endometrial sampling is complementary to D&C for the diagnosis of endometrial lesions and it is necessary for it to be performed before D&C and/or hysterectomy.  相似文献   
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