白纹伊蚊幼虫龄期的发育历期

在实验室内20±1℃, 23±1℃, 25±1℃, 28±1℃和30±1℃恒温条件下, 观察了白纹伊蚊(Aedes albopictus)幼虫(广州株)的发育历期.幼虫的总发育历期和各龄幼虫的发育历期随温度的上升而缩短, 各龄幼虫历期在总发育历期中占有恒定的百分比, 据此计算出其捕获机率.各龄幼虫的发育历期与温度呈直线回归关系.通过积温公式, 求出各龄幼虫的积温常数.此外还探索了营养对幼虫发育历期的影响, 从而影响各龄幼虫捕获机率的计算.     

内毒素对人血小板聚集,释放的体外作用

大肠杆菌 O55B5内毒素在体外可抑制人血小板自发性聚集,并使血小板内 cAMP、钙调素明显增高,但对肾上腺素诱发的血小板聚集无作用,也不能引起血小板致密颗粒和α-颗粒的释放。此外还观察到内毒素组无血小板上清液中5-HT 含量减少。     

福尔马林致痛提高大鼠中枢μ阿片受体密度及电针的加强作用

用放射自显影方法观察到;（１）大鼠脚掌注射福尔马林后,某些与镇痛有关的脑区如尾核头部、伏隔核、杏仁核、中央灰质、脚间核、中缝大核、脊髓背角等结构中μ阿片受体密度明显增加（Ｐ＜０．０５,Ｐ＜０．０１）;（２）给予电针抑制痛反应的大鼠,在其大部分上述结构及扣带回、隔区、视前内侧区、内膝体、上丘、中缝背核及中央上核受体密度明显增加;与福尔马林注射组相比,脚间核、中央灰质尾端腹外侧区、腰膨大背角的受体密度进一步增加。从而在受体水平支持伤害性刺激可以激活体内内阿片肽能活动,而电针可以加强这一活动的设想。     

Role of calcium in differentiation of murine erythroleu-kemia cells

Calcium plays a crucial role in the normal and abnomal cell metabolism.The role of calcium in the differentiation process of murine erythroleukemia cells(MELC)remains controversial.Here,based upon quantitative measurement of fluorescence in single cells,a method was developed to investigate the intracellular free calcium[Ca^2 ]i concentration and DNA contents simultaneously,by employing the fluorescent probe,fluo-3 acetoxymethyl ester and DNA dye Hoechst 33342.During MELC differentiation.[Ca^2 ]i concentration incresed.We also demonstrated that calcium ionophore,A23187,enhanced the HMB-induced MELC differentiation,while verapamil,an inhibitor of calcuim uptake,slightly reduced differentiation.These results suggested that an increase in the [Ca^2 ]i level was an essential step in HMBA-induced MELC differentiation.     

变黄黑文衣,中国黑文衣属地衣一新记录种

通过对文字衣科黑文衣属形态学、解剖学、化学与分子生物学的研究,发现中国新记录种1种,即变黄黑文衣(Phaeographis flavescens Dal-Forno&Eliasaro),该种主要特征为地衣体壳状,表面浅黄绿色,无光泽,光滑;子囊盘弯曲,多分支,聚生于假子座中;盘缘黑色,相邻线盘之间有小缝隙,盘面较平坦,黑色,覆有白色粉霜;子囊层无色透明,侧丝顶端分支;子囊含8个子囊孢子;子囊孢子褐色,横隔透镜型,(4～)6胞室,大小19～25.5μm×6～7μm,I+紫红色。该种分布于云南和福建,该研究丰富了对中国黑文衣属物种组成与分布的认知。     

远交系小鼠胚胎干细胞系的建立及嵌合鼠的获得

ＥＳ细胞（ＥｍｂｒｙｏｎｉｃＳｔｅｍＣｅｌｌｓ）是来源于小鼠早期胚胎的多潜能干细胞,它可以在体外大量培养。并以单细胞的形式注射到早期胚胎里,发育为嵌合体。到目前为止,通常使用的１２９小鼠品系是来源于近交系（ｉｎｂｒｅｄ）小鼠的胚胎．与之相比,远交系小鼠应当具有较强的生命力和抗病能力。曾有人报道过建成了远交系小鼠胚胎干细胞系,但是尚没有见到获得嵌合鼠的报道。有人甚至认为：由于不同品系小鼠所具有的遗传背景不同,有的小鼠不能建成ＥＳ细胞系。最近,本实验室在这方面做了有益的探索,成功地建成了远交系小鼠胚胎干细胞系,并在这里报导首例用远交系小鼠胚胎干细胞系培育成功嵌合体小鼠。采用源于Ｓｗｉｓｓ小鼠远交群的昆明（ＫＭ）品系小鼠囊胚建成了三个小鼠胚胎干细胞系（ＫＥ１．ＫＥ２．ＫＥ５）。核型正常率均达到７０％以上。自第八代起分批冻存,复苏后,培养至第１２代,消化成单细胞,通过囊胚显微注射,将其注射到６１５品系小鼠胚胎。在幸存的幼鼠中获得了一只来源于ＫＥ１细胞的嵌合鼠（Ｔａｂｌｅ１）．其毛色表现为受体鼠（６１５）的白色中嵌合有供体鼠（ＫＭ）的黑褐色（ＰｌａｔｅＩ－Ａ）．嵌合鼠与受体鼠的杂交后代鼠中仍然出现了受体鼠的毛色类型（     

In vitro stimulation of alkaline phosphatase activity in immature embryonic chick pelvic cartilage by adenosine

Cyclic AMP content in embryonic chick pelvic cartilage increases significantly as the embryo ages from 8 to 10 d. This in ovo elevation in cyclic AMP content precedes maximal cartilage alkaline phosphatase activity by some 24 h. We studied whether this temporal relationship may be causally related, using an in vitro organ culture. Incubation of pelvic cartilage from 9- and 10-d embryos in medium containing monobutyryl cyclic AMP (BtcAMP) resulted in significant increases in alkaline phosphatase activity (220 and 66 percent, respectively) as compared to that of cartilages incubated in medium alone. This stimulation was both concentration- and time-dependent with maximal response at 0.5 mM BtcAMP and 4-h incubation, respectively. Similar incubations of cartilage in medium containing 1-methyl-3-isobutyl xanthine (MIX), 0.25 mM, also resulted in increased alkaline phosphatase activity (114 percent). However, pelvic cartilage from 11-d embryos incubated in medium containing BtcAMP or MIX showed no increase in alkaline phosphatase activity. We postulated that developmental age was the factor responsible for this difference in response and that immature cartilage (that with little or no alkaline phosphatase activity) would respond to BtcAMP whereas mature cartilage (that with significant alkaline phosphatase activity) would not. This was tested by incubating end sections of 11-d cartilage, which have little alkaline phosphatase activity, and center sections, which have significantly alkaline phosphatase activity, with both BtcAMP and MIX. Alkaline phosphatase activity in end sections (immature cartilage) was stimulated by BtcAMP and MIX, whereas it was not stimulated in the center sections. Actinomycin D and cycloheximide inhibited BtcAMP and MIX stimulation of alkaline phosphatase activity. Thus, the in vitro data suggest that cyclic AMP is a mediator for the stimulation of alkaline phosphatase activity in embryonic cartilage.     

湖北省潜水蜂一新种（膜翅目：潜水蜂科）

潜水蜂属Agriotypus Curtis全世界共报道8种,其中我国已知4种。本文新添一采自湖北省房县的新种:郑氏潜水蜂A.zhengi sp.nov。     

油菜FBA基因克隆、表达分析及其与抗旱性的关系

为了解果糖-1,6-二磷酸醛缩酶(fructose-1,6-bisphosphate aldolase,FBA)在油菜抗旱中的作用,揭示油菜干旱胁迫下FBA基因表达量、光合指标、产量等之间的关系,为油菜等作物抗旱性鉴定和抗旱性改良提供依据。以抗旱性强的甘蓝型油菜94005为材料,在初花期进行干旱胁迫处理,以正常浇水作为对照;测定叶片光合参数和FBA酶活性,通过实时荧光定量PCR(RT-qPCR)分析FBA基因的表达量;采用RACE方法对FBA基因进行全长克隆,并对测序结果进行生物信息学分析;复水后生长至成熟期测定产量,分析产量、光合指标、FBA基因表达量等之间的关系。结果表明,随着干旱的加剧,油菜叶片的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、产量均下降,FBA活性和FBA基因的表达量上升。在轻度、中度和重度干旱胁迫下,油菜叶片胞间CO_2浓度(Ci)显著下降,水分利用率(WUE)上升;极度胁迫下,Ci上升,WUE下降;油菜产量、净光合速率与FBA活性和FBA表达量呈显著负相关。FBA基因全长序列1440bp,ORF(开放阅读框)位于60—1172区域,编码370个氨基酸;蛋白分子量为38.51 KDa,等电点6.92;同源性对比显示,甘蓝型油菜FBA基因与拟南芥FBA基因的一致性在87%以上。二级结构预测结果表明FBA蛋白由α-螺旋、无规则卷曲、延伸链以及β-转角组成,4种二级结构元件所占比例分别为43.85%、31.28%、17.60%、7.26%。因此,干旱胁迫下油菜的净光合速率下降、产量降低,随着胁迫的加剧,降低幅度增大。FBA基因与干旱胁迫密切相关,干旱胁迫下,FBA基因主要通过抑制光合、降低蒸腾、促进糖酵解和有氧呼吸等途径来提高植物对干旱胁迫的适应性。