黑斑蛙松果复合体的形态结构研究

黑斑蛙松果体由额器和松果体本部两部分组成，额器位于颅骨外，两眼之间皮肤的真皮层内，呈一团致密细胞，其结构和位置与其它变温动物的松果眼不同，缺乏感光结构，光果体本部包括脑旁体和松果体本体，主要成分有光接受细胞，支持细胞，血管和神经纤维。光接受细胞除具有许多和视锥，视杆细胞相似的细胞学特征，如排列不规则的外节，内节和突触成分外；胞质内还含有大量的线粒体，核糖体粗面和滑面内质网，中等量的高尔基复合体及少     

刚刺颚口线虫病流行区的发现及其生物学研究

剖检猪 1 213只,平均感染率 23.6％。鱼类检查 19种,本虫第三期幼虫阳性者 7种。两栖类检查 4种,阳性 2种,其中虎纹蛙 Rana tigrina rugulosa 是转续宿主新纪录,感染率高达 50％。家猪每月定点调查结果表明全年均可受本病侵袭,春夏季感染率高于秋冬季;湖区感染率明显高于非湖区。对终宿主和中间宿主体内寄生的2种易混淆的颚口线虫鉴别特征作了简述。扼要讨论了防治措施。     

Membrane permeability changes duringRana oocyte maturation

A transition from an open system to a closed one must occur during the complex process of meiotic maturation of the amphibian oocyte. Membrane permeability to urea inRana oocytes following progesterone stimulation was determined, and the largest decrease was found to coincide with germinal vesicle breakdown. These findings suggest that the timing of the disappearance of membrane permeability correlates with developmental events that prepare the oocyte for a hostile environment.     

Differential sensitivity of amphibian nodal and paranodal K+ channels to 4-aminopyridine and TEA

Summary Voltage-dependent K⁺ channels are blocked by several drugs, including 4-aminopyridine (4-AP) and tetraethylammonium (TEA). 4-AP is most widely used to localize K⁺ channels in mammalian and non-mammalian nerve fibers, but 4-AP and TEA alter various K⁺ channels and/or preparations in specific ways. The reason is not known, in part because dissociation constants for 4-AP and TEA have not been measured for nodal and internodal K⁺ channels in the same fibers. Smith and Schauf showed that the density of nodal versus paranodal K⁺ channels in frog nerves depends on fiber diameter. This size dependence was used to determine the relative sensitivity of nodal and internodal K⁺ channels to 4-AP and TEA, and to compare voltage- and time-dependent activation. The results show nodal and internodal K⁺ channels activate similarly. However, internodal channels are selectivity blocked by 4-AP while TEA is more effective on nodal channels. A high sensitivity of internodal K⁺ channels may explain why 4-AP improves symptoms in diseases such as multiple sclerosis.     

实验温度对牛蛙神经冲动产生和传导的影响

测定了牛蛙(Rana catesbeiana)离体坐骨神经干在5、15、25、30、33、35、39℃七个温度条件下的动作电位波幅和传导速度.结果表明:温度显著影响牛蛙神经干的动作电位幅度和传导速度,牛蛙神经干动作电位幅度和传导速度不随温度的改变而呈同步的变化.在5-30℃温度范围内,牛蛙神经干的动作电位幅度随温度升高而增大,30℃后显著下降,39℃时最低;25、30、33℃动作电位的传导速度相对较快,温度低于25℃或高于33℃,牛蛙神经干的传导速度均呈显著的下降趋势.     

饲料对中国林蛙蝌蚪期生长发育的影响

在前人工作的基础上,分别用单纯植物性饲料、单纯动物性饲料和两者混合制成的饲料饲养中国林蛙蝌蚪,在发育的不同阶段对不同饲料饲养的蝌蚪的体长、体质量等项指标进行测定．发现饲料对中国林蛙蝌蚪的体长、体质量和发育速度都有影响,这对于人工养殖中国林蛙具有重要意义．     

虎纹蛙的早期胚胎发育

报道了虎纹蛙的早期胚发育,自受精卵期至鳃成期共分２５时期,其发育进程及各期胚胎的形态特征与一般蛙科种类基本相似,但其受精卵期和８细胞期有明显的特异之处,在水温１８－２３℃下,其胚胎发育的全过程历时约１２６ｈ。     

Cu2+和Cr6+对中国林蛙蝌蚪的急性毒性

采用中国林蛙(Rana chensinensis)出膜后一周的蝌蚪为实验对象,研究了Cu2 和Cr6 对中国林蛙蝌蚪的急性毒性.实验结果表明,在水温22℃～24℃条件下,Cu2 对中国林蛙蝌蚪24 h,48 h,72 h的半致死浓度(LC50)分别为0.131,0.105,0.038 mg/ L;Cu2 对蝌蚪的安全浓度为0.02 mg/ L.Cr6 对中国林蛙蝌蚪24 h,48 h,72 h的半致死浓度(LC50)分别为4.16,4.48,4.57 mg/ L;Cr6 对蝌蚪的安全浓度为1.55 mg/ L.同时讨论了中国林蛙与其他两栖类蝌蚪相比对Cu2 和Cr6 耐受性的差异.     

辽宁产中国林蛙早期胚胎发育研究

在恒温条件下，观察了辽宁产中国林蛙的正常胚胎发育。根据基外形变化和胚胎主要特征的出现以及胚胎的行为，将其胚胎发育划分为２５个期。从卵子受精开始至蝌蚪的鳃盖闭合，出水孔形成止。１８℃时共历时１５１．５６ｈ。     

黑斑蛙Sox基因的PCR扩增

以特异扩增人SRY基因HMG -box保守区的一对引物 ,扩增了黑斑蛙的Sox基因 (SRY -boxgene) .结果表明 ,雌雄黑斑蛙个体均扩增出了两条带 ,大小分别为 4 50bp和 90 0bp ,显示了Sox基因在黑斑蛙雌雄个体间无性别特异性 ,且可能含有内含子 .本文为探讨黑斑蛙的性别决定机制及Sox基因的进化提供了分子资料 .