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511.
Targeting nuclear receptor RORγ is recognized to be beneficial in multiple autoimmune disorders. We disclosed new indole analogues as potent RORγ inverse agonists. RO-2 as one of the potent and orally bioavailable compounds was evaluated in various models of autoimmune disorder. It showed potent suppression of downstream markers of RORγt activity in murine and human primary cells, ex vivo PD assay and in multiple animal models of autoimmune diseases. The results indicate the potential of these indole analogues as orally bioavailable small molecule inverse agonists of RORγt, efficacious in various Th17 driven models of autoimmune disorders.  相似文献   
512.
513.
The Gilbert Bay, Labrador, MPA (Marine Protected Area) was created in 2005 to protect a genomically distinct and locally adapted bay resident population of Atlantic cod (Gadus morhua) from commercial overfishing. Since then research showed that significant numbers of individuals migrate beyond MPA boundaries creating a concern that fishing continues to impact this endemic population. As part of research and MPA monitoring to assess the health of the protected cod population, lethal sampling of Gilbert Bay cod was conducted from 1998 to 2009 to gather length-at-age data from otoliths. Since then only non-lethal sampling methods were used so as to help conserve the protected population. This study was conducted to compare non-lethally (mark-recapture and length-frequency) obtained age and growth data with lethally (otolith-length-at-age) obtained data. The three methods produced similar results for the 1998 to 2009 period, and both of the non-lethal methods considered were consistent over the 20 year study, confirming their preference over lethal methods for this small endemic fish population.  相似文献   
514.
从牙齿结构推断年龄   总被引:1,自引:0,他引:1       下载免费PDF全文
冯家骏 《人类学学报》1985,4(4):379-384
本文设计了改良的冠室指数公式。用求积仪对91例上颌第一磨牙磨片的釉质、冠部牙本质和髓室的面积进行了测量,经统计学处理求得冠室指数与年龄关系的回归方程式:Y=72.32-0.442x(Y为推断年龄,x为冠室指数)。  相似文献   
515.
长江三峡库区分布的中国种子植物特有属   总被引:3,自引:0,他引:3  
贺昌锐  陈芳清   《广西植物》1999,19(1):43-46
长江三峡库区分布中国特有属67属,占库区种子植物区系属的6.4%,其中木本属28属,草本属39属,集中分布在川东、鄂西一带。本文主要对长江三峡库区中国种子植物特有属的物种组成、分布及特点进行分析,并对三峡库区众多中国种子植物特有属形成的原因及其在库区植物区系研究中的地位进行了讨论。  相似文献   
516.
三峡库区稀有濒危植物异地保护群落设计的初步研究   总被引:9,自引:1,他引:8  
提出了建造群落舁地保护三峡库区稀有濒危植物的方法。从地点选择、面积确定、物种组成和群落结构等方面探讨了异地保护群落设计的原理和方法。根据对三峡库区及其附近的残存稀有濒危植物群落的调查,选择九宫山自然保护区的一个独特生境,设计了一个面积约3000m^2,优势种为珙桐(Davidia involucrata)、金线槭(Dipteronia sinensis)、水青树(Tetracentron sinr  相似文献   
517.
云台山地区有29种两栖动物(8种)和撤地动物(21种),其中吉北界种有10种,占34.5%,东洋界种有7种,占24.1%,广布种有12种,占41.4%。该地区两栖爬行运行种类和动物区系组成与北部邻省山东省相似,而与苏北其它邻近地区相差较大,建议在江苏省两栖扬弃行运行地理区划出“云台低山丘陵区”(或苏东北低山丘陵区)。  相似文献   
518.
Abstract. We examined the vegetation of the Southeast Saline Everglades (SESE), where water management and sea level rise have been important ecological forces during the last 50 years. Marshes within the SESE were arranged in well‐defined compositional zones parallel to the coast, with mangrove‐dominated shrub communities near the coast giving way to graminoid‐mangrove mixtures, and then Cladium marsh. The compositional gradient was accompanied by an interiorward decrease in total aboveground biomass, and increases in leaf area index and periphyton biomass. Since the mid‐1940s, the boundary of the mixed graminoid‐mangrove and Cladium communities shifted inland by 3.3 km. The interior boundary of a low‐productivity zone appearing white on both black‐and‐white and CIR photos moved inland by 1.5 km on average. A smaller shift in this ‘white zone’ was observed in an area receiving fresh water overflow through gaps in one of the SESE canals, while greater change occurred in areas cut off from upstream water sources by roads or levees. These large‐scale vegetation dynamics are apparently the combined result of sea level rise ‐ ca. 10 cm since 1940 ‐ and water management practices in the SESE.  相似文献   
519.
Summary In the borderline area between the hemal milieu of the choroid plexuses (PC) and the interstitial cerebrospinal-fluid (CSF) compartment, ground substances displaying increased amounts of basal lamina-like material and containing negatively charged sulfated glycosaminoglycans appear to be endowed with selective properties. They may function as a sieve or filtration barrier gradually controlling the passage of substances between the two milieus, depending on their charge and molecular weight. Special structural features and functional properties of ependymal cells are associated with such bordering structures. These ependymal cells are transitional elements between choroid epithelium and ciliated ependymal cells. As judged from experiments with horseradish peroxidase and conventional electron microscopy, occluding junctions at the basal pole of these cells prevent a rapid alteration in the milieu conditions, enabling gradual change from hemal to CSF composition near the bases of these transitional ependymal cells. The borderline structures between the hemal milieu of the PC and the area postrema (1) are established by leptomeningeal cells which face a hemal mileu, (2) are endowed with conspicuous tight junctions, and (3) produce a flocculent substance, the light-microscopic equivalent of which is PAS positive. These structures probably establish an effective barrier between the two milieus of different composition. The functional characteristics and the morphology of the meningeal cells facing the hemal milieu of neurohemal regions resemble closely the neurothelial cells, which are interposed between the CSF milieu and the hemal milieu in the dura mater. The present results suggest that the location between the hemal and the CSF milieu is decisive for the transformation of leptomeningeal cells into neurothelial elements.Supported by the Deutsche Forschungsgemeinschaft (Grant Kr 569/5-1)Dedicated to Professor Dr. med., Dr. med. vet. h.c., Dr. phil. h.c. Andreas Oksche on the occasion of his 60th birthday  相似文献   
520.
三峡工程与江汉平原农业持续发展   总被引:2,自引:0,他引:2  
三峡工程与江汉平原农业持续发展朱俊林(湖北大学生态学研究所,武汉430062)InfluencesoftheThree_GorgeProjectontheAgricultureinJianghanPlainAreaandtheA┐gricultura...  相似文献   
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