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1.
P物质对大鼠DRG神经元胞体膜的作用   总被引:17,自引:1,他引:16  
本文在大鼠DRG神经元标本上应用细胞内记录,以确定SP对DRG细胞的膜反应及其可能的离子机制。实验所测DRG细胞静息膜电位为-58.9±8.2mV(X±SE,n=81)。传导速度:A_(α/β)细胞为20.4±4.8m/s(X±SE),范围14.1-28.7m/s(47/60);Aδ及C类细胞为9.8±5.2m/s,范围1.2-13.7m/s(13/60)。浴槽滴加SP(10 ̄(-7)-3×10 ̄(-4)mol/L)在大多数细胞可引起明显的膜去极化反应(56/60)。少数细胞对SP无反应(4/60)。在SP去极化期间膜电导值有所增加,从平均值2.72×10 ̄(-8)mho增加24.6%(n=3)。所测逆转电位值在+40-+50mV之间(n=3)。浊流平衡液(BSS)中NaCl以氯化胆碱置代,或用含TTX(10 ̄(-5)mol/L)的BSS灌流,可使SP-去极化幅值大大减小但不能完全消除。而高(20mmol/L)和低(0mmol/L)Ca ̄(2+)的BSS灌流时,使SP-去极化幅值相应的增加和降低。用含10 ̄(-4)mol/LCd ̄(2+)及10 ̄(-2)mol/LTEA的BSS灌流,均使SP-去极化明显减小。  相似文献   

2.
山东10种植物的核型分析   总被引:6,自引:1,他引:5  
杨德奎  周俊英   《广西植物》1999,19(4):349-354+395
对山东10 种植物进行了核型分析。茴茴蒜( Ranunculuschinensis Bge-) 染色体数目2n =16 , 核型公式K(2n) = 2x = 16 = 2 M + 2m + 2sm + 10st, “3A”类型; 五脉地椒( Thymusquinquecostatus Celak-) 染色体数目2n= 26 , 核型公式K (2n) = 2x= 26 = 8 M + 18m , “1A”类型; 蛇床( Cnidium monnieri(L-) Cuss-) 染色体数目2n= 20 , 核型公式K (2n) = 2x= 20 = 2M+ 16m + 2sm , “2B”类型; 波斯菊( Cosmos bipinnatus Cav-) 染色体数目2n = 24 , 核型公式K(2n) = 2x = 24 = 16m + 2m (sat) + 6sm , “2A”类型; 白车轴草( Trifolium repens L-) 染色体数目2n= 32 , 核型公式K (2n) = 4x = 32 = 32m , “1A”类型; 铁苋菜( Acalypha australis L-)染色体数目2n = 32 , 核型公式K (2n) = 2x= 32 = 32m , “1B”类型; 地构叶( Speranskia t?  相似文献   

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胡边  孙金海 《遗传》1999,21(5):27-30
对家猪不同品种及家系间的染色体组型、C-带、Ag-NORs多态性进行的研究表明:杜洛克猪:约克夏猪、长白猪体细胞染色体数2n-38、核型2n=10sm+12m+4st+12t,而13/17易位纯合子猪(36,rob.13/17)的体细胞染色体数2n=36。核型2n=10sm+12m+6st+8t;13/17易位杂合子猪(37,rob.13/17)的体细胞染色体数目为2n=37,核型为2n=10sm  相似文献   

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最大摄氧量(Vo2max)是评价人体体力的重要指标,其测定方法分直接法和间接法两种。目前所推导的间接计算公式都是在平原、或是在进入高原初期推导的,不适用于高原习服人群。本研究采用逐步回归的方法,推导出移居高原7-27个月、不同高度的青年男性Vo2max间接计算公式。在海拔3680m地区,Vo2max(L/min)=1.1531+0.007327身高(cm)+0.01613体重(kg)-0.005883晨脉(b/min)-0.004534运动心率(60W,6/min),R=0.745,P<0.01,SS=3.7799;或Vo2max(L/min)=1.2186+0.01984体重(kg)+0.07259肺活量(L)-0.006659晨脉(b/min),R=0.713,p<0.01,ss=3.9636。在4350m地区,Vo2.max(L/min)=0.4917+0.01687体重(kg)+0.1109肺活量(L)+0.001983屏气时间(S),R=0.781,P<0.01,SS=2.1356。计算值与实测值比较,变异系数在13%以内,结果准确可靠,适用于青年男性高原习服移居者。  相似文献   

5.
采用大鼠海马脑片体外缺血模型,观察海马突触体内蛋白激酶C(PKC)活性的变化,以及这种变化对突触体谷氨酸(GLU)摄取的影响。结果显示:海马脑片体外“缺血”10min,其突触体内PKC活性基本不变,而缺血30min,突触体内PKC活性显著上升(P<0.01,n=6);非N-甲基-D-天门冬氨酸(NMDA)受体拮抗剂DNQX有效地抑制PKC活性的同时,可降低胞外GLU的堆积,而NMDA受体阻断剂AP_5无作用。进一步实验证明,PKC激动剂PDB浓度依赖性地抑制突触体对3H-GLU的摄取(IC50=131±10μmol/L),此抑制作用可由PKC抑制剂H-7(100μmol/L)抵消。提示脑缺血诱发GLU堆积的作用机理可能是:脑缺血引发钙内流导致GLU过量释放,GLU又通过突触前非NMDA受体激活PKC,抑制其自身摄取,正反馈性加重胞外GLU的堆积。  相似文献   

6.
Ca^2+敏感性微电极在心肌胞浆Ca^2+活度检测中的应用   总被引:1,自引:0,他引:1  
王镇辛  马逸龙 《生理学报》1994,46(4):409-414
改进的中性载体Ca2+敏感性微电极(Ca-ISE)在尖端直径为0.4—0.8μm时仍具有良好特性,可用于心肌胞浆Ca2+活度(αCai)的检测。测得豚鼠右心乳头肌、狗心室肌和浦肯野纤维静息时分别为0.19±0.01(n=22),0.20±0.02(n=11)和0.46±0.07(n=13)μmol·L-1。毒毛旋花苷G3μmol·L-1使静态及动态心肌分别增高0.18±0.02和6.69±2.09μmol·L-1(n=22),并出现触发活动(TA)。100μmol·L-1蝙蝠葛碱可抑制毒毛旋花苷G引起的增高,同时使其TA消失。表明Ca-ISE技术可用于心肌组织TA与的同步检测。  相似文献   

7.
本文报道了我国蒿属6种的染色体核型,它们的核型公式分别为:牡蒿(ArtemisiajaponicaThunb.)2n=18=12m+6sm(2SAT);西南牡蒿(A.parvifloraBucb.-Ham.exRoxb.)2n=36=30m+4sm+2st(6SAT);多花蒿(A.myrianthaWall.exBess.)2n=36=30m+6sm:牛尾蒿(A.dubiaWall.exBess.)2n=36=28m+8sm(2SAT);野艾蒿(A.lavandulaefoliaDC.)2n=54=42m+12sm;荚毛蒿(A.velutinaPamp.)2n=54=36m+18sm.  相似文献   

8.
吉林省产5种百合的核型研究   总被引:17,自引:0,他引:17  
报道了吉林省产5种百合科植物的染色体数目和核型:①毛百合Lilium dauricum Ker.-Gew1.2n=24=2m(2SAT)+2sm(2SAT)+8st(2SAT)+12t(2SAT);②有斑百合L.concolor Salisb.var.buschianum(Lodd.)Baker 2n=24=2m(2SAT)+4sm(4SAT)+6st(2SAT)+12t;③兰州百合L.david  相似文献   

9.
MPEG-SOD对急性低氧下鼠左心功能的保护作用   总被引:1,自引:0,他引:1  
单甲氧基聚乙二醇(MPEG)活化后与超氧化物歧化酶(SOD)偶联,经纯化后得到MPEG-SOD,鉴定其分子量约为7.0×105Dation。其在血液循环中酶活性半衰期超过30h,远大于天然SOD(6-10min)。SD雄性大鼠分三组.对照组(n=8.由股静脉注入0.2ml生理盐水)、NativeSOD组(n=8,注以0.2ml生理盐水配的800USOD)和MPEG-SOD组(n=9,注以800UMPEG-SOD)。低氧前三组鼠的心率(HR)、左室内峰压(LVP)、左室压微分(LV±dp/dtmax)和股动脉压(AP)均无统计学差别。在模拟6000—6500m高度急性低氧1.8.14min记录上述各项指标,结果如下:除HR外,NativeSOD组与对照组各指标均无统计学差别,MPEG-SOD组的各项指标均明显高于对照组。表明MPEG-SOD对急性低氧导致的左心室力学指标的减弱有明显保护作用,提示超氧自由基(O2-)在急性低氧导致左心室功能损伤中起重要作用,即可能是由O2-及其衍生的其它自由基损害心肌细胞生物膜系统所致。  相似文献   

10.
青海南部太白韭4居群的核型研究   总被引:1,自引:0,他引:1  
研究了葱属太白韭青海4个居群的染色体数目和核型。结果如下,居群1:2n=2x=16=12m+2sm+2st(2SAT),居群2:2n=2x=16=14m+2st(2SAT);居群3:2n=4x=32=24m+4sm+4st(4SAT),居群4:2n=2x=16=14m+2st(2SAT)+Bs(0-2)。并讨论了多倍体和B染色体形成与分析。  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   

16.
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   

17.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

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