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1.
用4头装有长久性颈静脉导管的3个月龄杂种小母猪,日糖添喂1μg/g Cimaterol(CIM),研究5天内血清有关代谢物、酶活性激素水平的变化。服食CIM后,小母猪血清脲氮明显降低,FFA持续升高,GPT活性上升,SS含量显著降低,β-内啡肽水平显著升高,胃泌素水平也略有升高。结果表明:CIM显著增强小母猪蛋白质代谢,增加氮沉积,同时CIM有显著的脂肪动员作用。CIM的营养分重配作用机理可能与调  相似文献   

2.
选用24只2月龄SD处女鼠配对分组,实验组日粮添加10μg/g塞曼特罗(CIM),试验期30天。与对照组比较,CIM显著提高大鼠生长速度(27.30%,P<0.01)和胴体比率,降低腰胁部脂肪重,提高腓肠肌、比目鱼肌和趾浅屈肌的鲜重和RNA合量及PNA/DNA值,同时提高大鼠垂体和血清GH水平分别达36.70%(P<0.01)和23.77%(P<0.05),降低血清脲氮含量。表明CIM可显著促进大鼠生长,降低体脂含量,促进肌肉肥大,促进蛋白沉积。其作用机理可能还与其促进GH的合成和分泌有关。  相似文献   

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缺氧时大鼠红细胞变形性损伤的机制研究   总被引:5,自引:0,他引:5  
本实验通过测定平原和模拟高原减压缺氧30天大鼠红细胞滤过指数(IF)、红细胞内[pH]i、[K+]i/[Na+]i比值、[Ca2+]i、[Mg2+]i、平均红细胞体积(MCV)及平均红细胞血红蛋白浓度(MCHC),从而探讨缺氧条件下大鼠红细胞变形性损害的机制。结果发现:1.缺氧组大鼠红细胞[Ca2+]i明显升高,且与IF呈显著正相关,但[Mg2+]i无明显差异;2.缺氧组[K+]i/[Na+]i值较平原组明显降低,且与IF呈显著负相关;3.缺氧组MCHC与平原组无明显差异,但MCV显著升高;4.缺氧组红细胞内[pH]i较平原组明显升高。提示:缺氧时红细胞[Ca2+]i升高,[K+]i/[Na+]i值降低,MCV增大以及红细胞[pH]i值的改变在其变形性损伤中起重要作用。  相似文献   

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对379例良、恶性肝组织进行的免疫组织化学研究显示,33%的慢性迁延性肝炎(6/18)、76%的慢性活动性肝炎(26/34)、92%的肝硬变(57/62)和97%的肝细胞性肝癌(HCC)(58/60)中有HBxAg表达,阳性率高于HBsAg或HBcAg。癌周肝中的HBxAg阳性率显著高于非癌周肝。与其它2种HBV抗原不同,HBxAg表达在细胞类型上有较明显的选择性,在肝小多角细胞(SPLC)、小细胞性不典型增生(SCD)及HCC中较强。与IGFⅡ、c-erbB-2、c-myc和EGF-R表达进行的对照研究表明HBxAg与IGFⅡ和c-erbB-2这2种HCC发生相关基因的表达关系密切。PCNA染色结果显示HBxAg阳性组织的细胞增殖活性显著高于HBxAg阴性组织。我们的结果还表明HBxAg表达与肝细胞不典型增生的发生和进展有关、提出HBVX基因可能通过其表达产物(HBxAg)首先激活IGFⅡ、c-erbB-2基因,继而引起显著的SPLC增生和SCD而参与HCC发生的.  相似文献   

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达乌尔黄鼠染色体银染核仁组织者分析   总被引:2,自引:1,他引:1  
达乌尔黄鼠染色体银染核仁组织者分析ANALYSISONCHROMOSOMESAg-NORSOFCITELLUSDAURICUSKeywordsCilellusdauricus;Chromosome;Ag-NOR达乌尔黄鼠(cilellusdauric...  相似文献   

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社鼠核型的研究   总被引:2,自引:0,他引:2  
王金星  赵肖凡 《动物学报》1997,43(3):324-327
社鼠核型的研究KARYOTYPESOFNIVIVENTERCONFUCIANUS(RODENTIA:MURIDAE)关键词核型C带G带AgNORs社鼠KeywordsKaryotype,Cbanding,Gbanding,AgNORS,N...  相似文献   

7.
小鼠胸树突状细胞系自发分泌多种类型细胞因子   总被引:2,自引:0,他引:2  
建成小鼠胸腺基质细胞系,命名为MTSC4,经鉴定分析认为是DC来源。在无外来刺激条件下,MTSC4细胞可自发分泌多种类型细胞因子,已检测到的有IL-1,IL-6,IL-7,CSF,IFN及趋化因子(CF)等。其中IL-6,IFN为较高水平分泌量,IL-1、CF为中等水平,IL-7、CSF为较低水平分泌量。MTSC4不能自发分泌IL-3及TNFa。MTSC4的建立有利于分析胸腺选择特别是阴性选择的机  相似文献   

8.
海蛇乙醇浸出物对实验性大鼠关节炎的防治作用   总被引:2,自引:0,他引:2  
周少雄  肖桂元 《蛇志》1997,9(4):14-17
探讨大鼠灌胃给予海蛇乙醇浸出物(AEBFSS)对大鼠胶原性关节炎(CIA)的预防和治疗作用。方法用自制的可溶性猪尾Ⅱ型胶原注入实验大鼠左后足造成胶原诱导性大鼠关节炎模型。结果大鼠在致炎前口服AEBFSS,当剂量达含4.0mg浸出蛋白/kg,可明显推迟CIA发病时间,降低CIA发病率和减轻关节炎症状;大鼠发生关节炎后口服AEBFSS,可明显抑制CIA大鼠关节炎症的程度,其作用在用药后7天表现明显;关节组织病理检查表明,口服AEBFSS显著减轻了患鼠关节的炎症程度。初步分析表明,口服AEBFSS既降低了CIA患鼠血清抗CⅡ抗体水平,又对患鼠耳迟发型超敏反应(DTH)产生了明显的抑制作用。结论口服AEBFSS对大鼠胶原性关节炎有显著的防治作用,其机制同时涉及T和B淋巴细胞免疫。  相似文献   

9.
利用微丝(microfilament,MF)解聚药物细胞松驰素B(cytochalasinB,CB)处理G_0期小鼠C_3H_(10)T_(1/2)成纤维细胞,对G_0至S期DNA合成,胸腺嘧啶核苷激酶(thymidinekinase,TK)活性、TK基因表达、钙调素(calmodulin,CaM)水平和一些细胞周期早期基因的表达进行了观察,G_0期细胞经3mg/LCB处理2h,促MF解聚增强了血清对S期细胞TK活性、TK基因表达和DNA合成的刺激作用,并促进细胞提前进入S期.血清刺激G_0期细胞进入晚G_1期和S期时,CaM水平明显升高,而CB预处理则使CaM含量进一步增加,特别是CB处理促使S期CaM增加向核内转移.CB处理明显增强血清对c-jun、c-fos和c-myc基因表达的刺激作用,而PKC抑制剂H_7则抑制CB处理对这些基因转录的刺激作用,说明CB使G_0期细胞MF解聚刺激c-jun、c-fos和c-myc的转录活性与PKC的作用有关.结果表明G_0至S期早期MF的重组可促进细胞进入S期,增强DNA合成.  相似文献   

10.
以大麦(HordeumVulgareL)叶片为实验材料,研究盐酸胍处理大麦类囊体膜对金属阳离子调节激发能分配的影响。结果表明:当未用盐酸胍处理时,Mg2+对类囊体膜的F686/F736比值有显著的刺激作用,而用不同浓度盐酸胍处理类囊体膜,则明显阻滞Mg2+调节激发能向PSII分配,表明盐酸胍处理可能损伤类囊膜上LHC—II与Mg2+调节作用有关的蛋白质,从而导致Mg2+调节效应降低.用SDS—PAGE方法研究盐酸胍处理后的类囊体膜色素蛋白复合物的组成变化,结果表明盐酸胍处理导致MIC—II中MICP1和LHCP2组分消失,这说明盐酸胍处理阻滞Mg2+调节效应可能与LJIC—II上的LHCP1,LHCP2受损有关。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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