变性科学家

世上本无所谓“有代表性”的生物学家。来认识两位不适应自己本来性别的科学家，他们在职业生涯中改变了性别。下面会介绍他们怎样适应变性所带来的改变。     

Self-/conspecific discrimination and superparasitism strategy in the ovicidal parasitoid Echthrodelphax fairchildii （Hymenoptera： Dryinidae）

Superparasitism in solitary parasitoids results in fatal competition between the immature parasitoids, and consequently only one individual can emerge. In the semisoli- tary ovicidal parasitoid Echthrodelphaxfairchildii （Hymenoptera： Dryinidae）, 2 adults can emerge under superparasitism with a short interval （〈24 h） between the first and second ovipositions. We determined the female parasitoid＇s behavioral responses under self- and conspecific superparasitism bouts with first-to-second oviposition intervals of 〈2 h. The self- and conspecific superparasitizing frequencies increased up to an oviposition interval of 0.75 h, with the former remaining lower than the latter, particularly for oviposition intervals of _〈0.25 h, suggesting the existence of self-/conspecific discrimination. The superparasitizing frequency plateaued for oviposition intervals of _〉0.75 h, with no dif- ference between self- and conspecific superparasitism. The ovicidal-probing frequency did not differ under self- and conspecific superparasitism, and was usually 〈20%. The females exhibited no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny） and almost always laid female eggs for any oviposition in- terval under self- and conspecific superparasitism. The sex ratio was not affected by the type of superparasitism, oviposition sides, or the occurrence of ovicidal probing. These observed results about the oviposition side, ovicidal probing, and sex ratios differed from the predictions obtained assuming that the females behave optimally. Possible reasons for the discrepancies are discussed： likely candidates include the high cost of selecting oviposition sides and ovicidal probing, and, for the sex ratio, the low frequency of encountering suitable hosts before superparasitism bouts.     

生物的性别决定和性别分化及其在生产实践中的应用

生物的性别决定和性别分化既紧密联系、又有本质区别,通过事例进行解释和说明:在生产实践中,有些生物的性别需要调控,才能更好地服务于人类,并通过事例介绍了部分方法措施.     

发头裸腹zao雄性性别分化的诱导

本文报道了重金属铜，锌，镉对发头裸腹zao(Moina irrasa)雄性性别分化的诱导作用。     

用蝶啶荧光分析法推断大头金蝇成虫日龄

应用蝶啶荧光分析法分析了常见尸食性蝇类大头金蝇Chrysomyamegacephala成虫头部蝶啶含量与日龄间关系 ,以及温度、性别等对这种关系的影响。结果表明 ,日龄、温度和性别对成虫蝶啶含量均有显著影响 ,其中温度为主要影响因子。在 16℃、2 0℃、2 4℃、2 8℃和 32℃各恒温下 ,成虫头部蝶啶含量与日龄间存在显著的线性关系。雌雄成虫头部蝶啶积累速率 (或 )与温度 (t)的关系分别可用指数函数FV =0 0 12 88×e(0 2 2 41t-3 12 7) +0 36 49(r2 =0 9987)和线性函数MV =0 0 5 74t- 0 36 37(r2 =0 95 5 7)很好地加以拟合。依据恒温试验结果 ,提出了自然变温条件下成虫日龄的 3种候选估测方法 ,证实这 3种方法仅适宜雄成虫而不适于雌成虫 ,其中对雄成虫日龄估测的最小误差平均为 2 5 5d。最后实际应用中如何选用这 3种方法作了讨论。     

激素的新时期

Novo实验室的T.Chadwich博士叙述说,激素的新时期已经开始,在这个时期将有可能随意地制造对身体气质特应性及其他至今还没有认识到的大量特性起极大决定作用的激素并精确地“裁判”激素使之适应人体的需要。     

可溶性CD40配体通过miR-152/SOX11信号轴调节非霍奇金淋巴瘤Raji细胞的增殖和凋亡

目的 探讨可溶性CD40配体（soluble CD40 ligand, sCD40L）基于性别决定区Y框蛋白11(SRY-related HMG box 11, SOX11)信号轴影响非霍奇金淋巴瘤Raji细胞增殖和凋亡的机制。方法 对Raji细胞用sCD40L处理，或转染miR-152mimics过表达miR-152，转染miR-152 inhibitor抑制miR-152的表达，转染SOX11 siRNA沉默SOX11的表达；用CCK-8实验检测细胞活力，流式细胞术测定细胞凋亡，Western blot检测SOX11水平，EdU染色检测细胞增殖水平，免疫组织化学染色检测Cleaved Caspase-3水平，qRT-PCR检测miR-152表达水平；应用生物信息学软件预测miR-152的靶基因，双荧光素酶报告系统鉴定miR-152与靶基因的靶向关系。结果 sCD40L处理Raji细胞使其miR-152表达增多，SOX11水平降低，细胞存活率降低，细胞凋亡率升高。过表达miR-152和沉默SOX11均使Raji细胞存活率降低，细胞凋亡率升高。sCD40L处理联合抑制miR-152表达...     

黄瓜去顶苗花决定临界期的研究

黄瓜幼苗分别培养于诱化和诱导营养芽培养基后，逐日进行了交换培养基试验，并在培养开始２ｄ后去顶。诱导营养芽培养基中培养１－６ｄ后转入诱花培养基，成花率依次递降，７ｄ后再转成花率极低。诱花培养基中培养少于５ｄ即转诱芽培养基，成花率极低；培养６ｄ则跃增；并随诱花培养基中培养天数增加而成花率上升，直至１８ｄ达顶点。