金霉素和灭蚁灵的几种合剂对五种常见白蚁的毒力对比

通过三种抗生素对几种常见白蚁毒力的实验室生物测定,综合结果发现盐酸金霉素对白蚁肠内原生动物的毒力相对较优,可以用作杀白蚁剂配方中的有效组成成份。本试验的目的在于从一些金霉素和灭蚁灵的合剂中选择可用于防治白蚁的含抗生素成份的最佳有效配方。     

绿僵菌与白僵菌对黑翅土白蚁的室内毒力测定

白蚁是世界性的主要害虫之一,世界各大洲都有分布,其为害面积约占全球总面积的50％,尤其在热带、亚热带地区,白蚁为害更为突出(李桂祥等,1989)。福建省的白蚁种类之多位居全国第三。     

几种杀虫剂对小地老虎的毒力测定

本研究了９种杀虫剂对小地老虎Ａｇｒｏｔｉｓ ｙｐｓｉｌｏｎ（Ｒｏｔｔｅｎｂｅｒｇ）３龄幼虫的触杀毒力。结果得出,触杀毒力从大到小的顺序：功夫菊酯、溴氰菊酯、农哈哈、卡死克、拉维因、米满、辛硫磷、锐劲特、敌百虫。其中功夫菊酯、溴氰菊酯和农哈哈的触杀毒力最强,比敌百虫高出１００００倍以上,在生产上可推荐使用。本试验还发现３龄幼虫的体重对毒力也有一定的影响。     

几种常用农药对拉萨麦蚜的毒力测定

<正> 麦蚜是危害我区麦类作物的重要害虫,具有直接造成产量损失和传播病毒病双重危害。主要种类有:白无网长管蚜Metolophium albidum Hille Ris hambers、麦长管蚜Sitobion avenae(F.)和禾缢管蚜Rhopalosiphum padi(L.)。为监测其抗药性发生发展和科学用药提供依据,1986～1987年作者测定了几种常用农药对这些麦蚜的毒力。     

几种杀菌剂对黄瓜疫霉菌的毒力测定

采用菌丝生长速率法检测60%嘧菌酯悬浮剂、80%代森锰锌可湿性粉剂、75%百菌清可湿性粉剂、60%唑醚·代森联水分散粒剂、2%蛇床子素微乳剂、64%杀毒矾可湿性粉剂等6种杀菌剂对黄瓜疫霉菌的室内毒力。结果表明,唑醚·代森联和蛇床子素对黄瓜疫霉菌的毒力最高,EC50值分别为3.4143 mg·L-1和10.4641 mg·L-1。将两种原药混配后,表现出增效作用,在两者混配比为1∶2时增效最明显,EC50值为5.8178 mg·L-1。     

黑胸散白蚁和台湾乳白蚁对镇江地区几种常见木材品种的取食偏好性研究

【目的】本文研究了黑胸散白蚁Reticulitermes chinensis和台湾乳白蚁Coptotermes formosanus对镇江几种常见木材树种的取食偏好性,分析了白蚁种类和木材品种对白蚁取食偏好性和死亡率的影响,以期为本地区白蚁治理及预防提供科学依据。【方法】采取白蚁非选择性取食试验,研究两种白蚁分别取食香樟Cinnamonum campora、银杏Ginkgo biloba、水杉Metasequoia glyptostrodoides、垂柳Salix babylonica、广玉兰Magnolia grandiflora、枇杷树Eriobotrya japonica、马尾松Pinus massoniana 7种树种食料的取食偏好和死亡率,取食偏好采用白蚁取食率,即每克白蚁每天取食量(mg)评价。试验数据采用多因素方差分析。【结果】方差分析结果表明,白蚁种类和不同木材对白蚁取食率和死亡率均影响显著。在供试的7种木材中,黑胸散白蚁最喜食垂柳和马尾松,其取食率分别为31.46和30.59 mg;台湾乳白蚁最喜食马尾松、水杉和银杏,其取食率分别为26.53、21.82和21.81 mg。两种白蚁对银杏、垂柳、广玉兰这3种木材的取食率有显著差异,而对其他4种木材的取食率差异不显著。【结论】白蚁取食率和死亡率受白蚁种类和木材品种影响明显。7种供试木材中,两种白蚁都对马尾松显示出明显偏好,且死亡率最低。     

几种杀螨剂对食菌嗜木螨的毒力测定和菇房药效试验

毒力测定结果表明．五种杀螨荆对食菌嗜木螨的毒力顺序由高至低为：天力Ⅱ号、扑螨特、单甲胖、螨克、克螨特。药效试验显示,用天力Ⅱ号(0．12%灭虫丁可湿性粉剂)的250倍液和10%扑螨特乳油的1000倍液防治食菌嗜木螨可取得较好的防治效果。     

几种杀虫剂对西花蓟马的室内毒力

用浸渍法进行了7种杀虫剂对西花蓟马成虫和若虫的室内毒力测定。结果表明,多杀霉素(48 h)、甲氨基阿维菌素苯甲酸盐(48 h)、阿维菌素(48 h)、辛硫磷(24 h)对西花蓟马成虫的LC50值为0.0544-3.1573 mg.L-1,对西花蓟马若虫的LC50值为0.0219-1.0905 mg.L-1,是防治西花蓟马的较好药剂。     

7种杀虫剂对烟蚜的毒力测定

烟蚜是危害烟草的主要害虫之一,为寻找防治烟蚜的高效低毒药剂,本文采用浸叶法和浸渍法比较了藜芦碱、吡虫啉、啶虫脒、噻虫嗪、吡蚜酮、除虫菊素和双丙环虫酯7种药剂对烟蚜的毒力.结果表明,浸叶法处理后,噻虫嗪和吡虫啉对烟蚜的毒力较高,LC₅₀值分别为2.220 mg/L和2.619 mg/L;而浸渍法处理后吡虫啉和藜芦碱对烟蚜的毒力较高,LC₅₀值分别为1.203 mg/L和2.554 mg/L.吡虫啉在两种不同处理方法的试验中都显示对烟蚜有较高毒力,可以作为防治田间烟蚜的推荐使用药剂,在吡虫啉被限制使用的情况下,可选用噻虫嗪或藜芦碱防治烟蚜。研究结果可为烟蚜的有效防治提供科学的参考依据.     

三种杀虫剂对几种昆虫天敌的毒力测定

为了明确几种常用杀虫剂对捕食性天敌（异色瓢虫Harmonia axyridis Pallas、东亚小花蝽Orius sauteri Poppius、智利小植绥螨Phytoseiulus persimilis）和寄生性天敌（松毛虫赤眼蜂Trichogramma dendrolimi Matsumura、丽蚜小蜂Encarsia formosa Gahan、中红侧沟茧蜂Microplitis mediator Haliday）的影响,在室内采用标准生物测定方法测定了阿维菌素、吡虫啉和噻嗪酮对以上昆虫天敌的毒力。结果表明：三种杀虫剂对六种供试天敌的毒力大小表现出相似趋势,即阿维菌素 > 吡虫啉 > 噻嗪酮;三种药剂对寄生性天敌的毒力均显著高于捕食性天敌。因此在害虫综合治理中应尽量选用对天敌昆虫相对安全的昆虫生长调节剂类的噻嗪酮,以起到保护天敌的作用。     

鲫耳石重量与年龄的关系及其在年龄鉴定中的作用

耳石重量在年龄组间重叠较少,大小相近的个体,年龄大的,即生长慢的耳石重量比年龄小的,即生长快的大,不同龄组之间耳石重量有显著差异（P＜0．05）,按年龄组在耳石重量与相应的体长作图,可初步判断观测年龄的可靠性,分析耳石重量频率分布能分离出体长相近,年龄不同的个体,其结构与耳石年轮观测的基本一致,耳石重量与年龄呈显著线性正相关（P＜0．05）,用耳石重量与年龄关系估算的年龄从耳石上直接读取的年龄无显著差异（P＞0．05）,文中对耳石重量直接用于确定鱼类年龄的可能性作了分析和探讨。     

SEX RATIO SELECTION AND THE EVOLUTION OF ENVIRONMENTAL SEX DETERMINATION IN LABORATORY POPULATIONS OF MENIDIA MENIDIA

What happens when a population with environmental sex determination (ESD) experiences a change to an extreme environment that causes a highly unbalanced sex ratio? Theory predicts that frequency-dependent selection would increase the proportion of the minority sex and decrease the level of ESD in subsequent generations. We empirically modeled this process by maintaining five laboratory populations of a fish with temperature-dependent sex determination (the Atlantic silverside, Menidia menidia) in extreme constant temperature environments that caused highly skewed sex ratios to occur initially. Increases in the minority sex consistently occurred from one generation to the next across all five populations, first establishing and then maintaining a balanced sex ratio until termination of the experiment at 8 to 10 generations. The extent to which the level of ESD changed as balanced sex ratios evolved, however, was not consistent. Two populations that experienced high temperatures each generation displayed a loss of ESD, and in one of these ESD was virtually eliminated. This suggests that temperature-insensitive, sex-determining genes were being selected. In populations maintained in low temperature environments, however, the level of ESD did not decline. Instead, the response of sex ratio to temperature was adjusted upward or downward, perhaps by selection of sex-determining genes sensitive to higher (or lower) temperatures. The two different outcomes at low versus high temperatures occurred independent of the geographic origin of the founding population. Our results demonstrate that ESD is capable of evolving in response to selection.     

四种剧毒鹅膏菌肽类毒素的HPLC分离与鉴定

利用反相高效液相色谱（ＨＰＬＣ）、紫外吸收光谱、质谱分析了灰花纹鹅膏Ａｍａｎｉｔａｆｕｌｉｇｉｎｅａ,白毒鹅膏Ａ．ｖｅｒｎａ,鳞柄白毒鹅膏Ａ．ｖｉｒｏｓａ,豹斑鹅膏Ａ．ｐａｎｔｈｅｒｉｎａ等四种剧毒鹅膏菌的肽类毒素,结果表明：Ａ．ｆｕｌｉｇｉｎｅａ、Ａ．ｖｅｒｎａ含有九种标样毒素中的七种。Ａ．ｖｉｒｏｓａ含有标样中的五种;Ａ．ｐａｎｔｈｅｒｉｎａ含有标样中的四种毒素。Ａ．ｆｕｌｉｇｉｎｅａ的毒素含量最高,其中最重要的ａ－ａｍａｎｉｔｉｎ含量高达６７８８．２(ｇ／ｇ干子实体,是Ａ．ｖｅｒｎａ的４倍,β－ａｍａｎｉｔｉｎ含量（２６３３．８μｇ／ｇ干子实体）是Ａｖｅｒｎａ的６倍。     

混合稀土及化学药物添加剂与抗生素联合应用的抗菌效果测定

采用试管液体法在测定混合稀土及2种化学药物添加剂喹乙酸、阿散酸单独抗菌活性的基础上将它们与常用抗生素金霉素、土霉素进行组合联用,测定其联用后的抗菌效果。结果表明,混合稀土、阿散酸与金霉素、土霉素联合应用后呈相加作用或无拮抗作用。喹乙酸与金霉素、土霉素联合作用后有较好的协同抗菌作用。试验结果对于畜牧业生产中将化学药物添加剂与抗生素配合使用具有一定参考价值。     

EVOLUTION OF SEX DETERMINATION SYSTEMS WITH HETEROGAMETIC MALES AND FEMALES IN SILENE

The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex‐determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex‐determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family.     

用双波长薄层层析扫描法测定中药黄柏中小檗碱等生物碱含量的研究

本文以乙酸异戊酯—无水乙醇—甲酸(7:1:2)作展开剂,用双波长薄层扫描法测定了三种不同来源以及同种来源而产地不同黄柏药材中小檗碱及巴马汀含量,并评价黄柏质量。     

THE DETERMINATION OF CHLOROPHYLL a IN WATER CONTAINING SEDIMENT

SUMMARY

The presence of sediment at concentrations of 0,2% by mass in water samples significantly lowered the amount of chlorophyll a that could be measured. Two types of sediment differed in their ability to lower the chlorophyll a concentration. The chemically more active sediment had a marked depressive effect on the chlorophyll a concentration and the relationship between chlorophyll a and cell numbers in the samples was non-linear. It is recommended that the use of chlorophyll a as an indicator of biomass in water containing sediment should be approached with care.     

复方大黄配伍抗生素腹腔灌注法治疗急性出血坏死性胰腺炎的实验研究

目的：实验观察大黄复方与抗生素配伍腹腔灌注对急性出血坏死性胰腺炎(ANP)的作用。方法：制备ANP模型,随机分组后分别以腹腔灌注给药,以ELISA法及鲎试验法检测血浆或组织中自细胞介素—6(IL—6)和内毒素脂多糖(LPS)水平。结果：各治疗组IL—6、LPS水平均明显低于实验对照组(非治疗组)。结论：大黄复方配伍头孢哌酮钠腹腔灌注法对ANP大鼠内毒素和炎性介质的产生有一定的抑制作用。     

两相滴定法测定苦参片中苦参碱的含量

用两相滴定法测定苦参片中苦参碱的含量。用NaCl饱和溶液为水相,含苦参碱的CHCl3为有机相,0．1％邻氯酚红为指示剂,在两相溶液中加入定量的酸标准液,充分振摇后,用标准碱液剩余滴定。加标回收,测定6次,平均回收率为：99．67％;RSD为1．86％(n=6)。     

ON THE PERSISTENCE OF OOCYTE NUCLEI FROM FETUS TO MATURITY IN THE LABORATORY MOUSE

Tritiated thymidine injected intraperitoneally into female mice midway through the gestation period was demonstrated by autoradiographic methods to be incorporated into the nuclei of oocytes of female embryos, observed at the pachytene stage of meiosis 2 to 4 days after the injection. The tritium label was also demonstrated in the oocyte nuclei of the daughters of similarly treated females at maturity (6 weeks post partum). It was also found that some follicle cells, likewise labeled with H³-thymidine in mid-fetal life, persisted to maturity with few or no intervening mitoses. The observations are presented in support of the prevailing view that individual oocytes which arise from germ cell primordia in fetal stages become the egg cells of the adult female mammal.