离散拓扑空间X上的超拓扑及P(X)上的核

本文给出了离散拓扑空间Ｘ上的九种超拓扑及其某些性质，并讨论了场所Ω（）＝Ｐ（Ｘ）的开核、闭核、最大核、最小核，并证明了Ｎ（Ｐ（Ｘ））为一个布尔代数。     

冰核细菌的分离和鉴定

于不同季节采集样品１８１种．分离获得３７５株细菌并采用经Ｌｉｎｄｏｗ修改的方法进行冰核活性测定，结果有２０株活性较高．并对其活性最高的２５６号菌株进行分类鉴定，归类为欧文氏菌的草生群     

LiCl致畸的蟾蜍胚胎发育早期外胚层细胞核超微结构观察

花背蟾蜍Bufo raddei胚胎发育早期,原肠期外胚层细胞核内含有大量凝聚状的异染色质块。神经板形成后,神经外胚层细胞核内染色质多呈分散状态,到较晚阶段,细胞核内有一部分染色质又由分散状态转变为凝聚状态,利用LiCl在囊胚中期前处理,可产生明显的胚胎背前部化发育,这样的胚胎其外胚层细胞核内染色质的超微变化与未处理胚胎的一致。     

巨细胞网状核5-HT能纤维对小脑浦肯野细胞自发电活动的影响

用电生理学方法、观察了小脑皮层第Ⅵ—Ⅶ小叶蚓部的浦肯野细胞（Purkinje cell,PC）对巨细胞网状核（Gigantocellularis reticularis nucleus,GI）刺激的反应特性,并观察了颈静脉注射5-羟色胺（5-HT）受体阻断剂二甲麦新碱（Methysergide）后GI刺激的效应。 结果表明:（1）刺激GI对小脑皮层Ⅵ—Ⅶ小叶PC自发放电的影响有抑制（41％）、兴奋（27％）及无明显作用（32％）三种形式,其中以抑制性作用为主。（2）GI刺激引起的PC反应在小脑皮层上呈区域性差异,表现为由VIA（64.3％）、VTB（65.3％）、VIC（71.4％）至Ⅶ小叶（74.2％）PC反应比率逐渐升高。（3）颈静脉注射二甲麦角新碱后,由GI刺激引起的PC自发放电的抑制性效应可逐渐被消除,而兴奋性效应则不被减弱。 结果提示:GI—小脑之间存在着5-HT能纤维投射,这些5-HT能纤维可能以“非突触释放”的形式调节着PC的机能活动。PC对GI刺激反应的区域性差异,可能与GI—小脑5-HT能纤维投射的解剖学分布特性有关。     

关于广义FitzHugh神经传导方程的周期波解

本文利用常微分方程周期解问题的一些已知结果,获得了保证广义FitzHugh神经传导方程周期波解存在的一些充分条件。     

Hopfield网络与Hamming网络的组合应用研究

本文首先从Hamming距离的角度对神经网络中有关Hopfield网络和Hamming网络的性能进行比较．分析了两种网络在各自单独应用时的优势与不足。然后结合数字显示模式实例探讨了这两种网络的一种组合应用。     

除草通对黑斑蛙红细胞核异常的诱导效应

采用旱田除草剂除草通对黑斑蛙进行染毒试验,研究其以不同浓度在不同时间范围内对黑斑蛙红细胞核异常的诱导效应,结果表明:核异常现象与除草剂浓度的相关性有一定的范围;随着时间的推移,黑斑蛙红细胞核异常率呈现先上升后下降的规律性变化.从整个实验结果看,旱田除草剂对水体的污染性不容忽视.     

腰上三角的临床应用解剖

目的：为肾脏疾病及腰疝的手术操作提供解剖学依据．方法：观察腰上三角的形态及构成，观察经过该三角前方的肋下神经、髂腹下神经和髂腹股沟神经的组合形式及走行．结果：腰上三角的形态可为四边形、三角形和不规则形；肋下神经、髂腹下神经和髂腹股沟神经在腰上三角前方有4种不同的组合形式．结论：熟悉腰上三角前方肋下神经、髂腹下神经和髂腹股沟神经的走行及与第12肋的位置关系，对于避免手术中损伤这3条神经具有重要的实际意义．     

HCN channels contribute to the intrinsic activity of cochlear pyramidal cells

A hyperpolarization-activated current recorded from the pyramidal cells of the dorsal cochlear nucleus was investigated in the present study by using 150- to 200-m-thick brain slices prepared from 6- to 14-day-old Wistar rats. The pyramidal neurones exhibited a slowly activating inward current on hyperpolarization. The reversal potential of this component was –32 ± 3 mV (mean ± SE, n = 6), while its half-activation voltage was –99 ± 1 mV with a slope factor of 10.9 ± 0.4 mV (n = 27). This current was highly sensitive to the extracellular application of both 1 mM Cs⁺ and 10 M ZD7288. The electrophysiological properties and the pharmacological sensitivity of this current indicated that it corresponded to a hyperpolarization-activated non-specific cationic current (I_h). Our experiments showed that there was a correlation between the availability of the h-current and the spontaneous activity of the pyramidal cells, suggesting that this conductance acts as a pacemaker current in these neurones. Immunocytochemical experiments were also conducted on freshly isolated pyramidal cells to demonstrate the possible subunit composition of the channels responsible for the genesis of the pyramidal h-current. These investigations indicated the presence of HCN1, HCN2 and HCN4 subunits in the pyramidal cells.Received 15 May 2003; received after revision 26 June 2003; accepted 21 July 2003     

Nerve growth factor activity of several immunal related serine proteases

Rabbit was immuned by the previously purified protein with high nerve growth factor (NGF) bioactivity (NGF_like protease) from \%Agkistrodon halys Pallas\% and the antisera were collected. The polyclonal antibodies were tentatively purified and then used as ligands of an affinity column. The \%A.h.Pallas\% crude venom was fractionated by this affinity column and then by Mono Q on fast protein liquid chromatography (FPLC). As a result, fraction Ⅱ and fraction Ⅲ were purified respectively, whose N_terminal amino acid sequences show high homology with the serine proteases in snake venoms, as well as the previous NGF_like protease. However, they possessed different levels of NGF bioactivity. The NGF activity of the previous NGF_like protease is equivalent to that of NGF, while the activity of fraction Ⅱ seems relatively low in contrast to fraction Ⅲ which had no NGF activity.