Ultrastructural Studies of Spermiogenesis of Conocephalus saltator (Saussure)

The acrosome of the spermatozoa is the organelle involved in its penetration through the ova membranes during the fertilization process. Several features of this process are considered to be related to the fertilization events e.g. some substance coats outside the membrane. During the maturation process the spermatozoa of Conocephalus saltator develop a coat of tubules and filaments which overly some membrane regions in a specific array. The mature spermatozoa are seen to adhere in these regions and form threads of 20 cells long and five to six wide. It is suggested that the external coat plays a role in this 'sticking' phenomenon.     

产超广谱β- 内酰胺酶肺炎克雷伯菌耐药性及其基因分型分析

目的:了解新疆独山子地区肺炎克雷伯菌超广谱β-内酰胺酶(ESBLs)的发生率、作为指示剂的五种抗生素的检出情况及ESBLs主要基因型。方法:收集临床分离的148株肺炎克雷伯菌,采用双纸片协同筛选法、NCCLS推荐的表型筛选和确证试验对细菌进行ESBLs产酶株的识别;耐药基因的质粒重组、转化,聚合酶链反应(PCR)扩增阳性产物测序,通过GenBank对序确定基因型。结果:本地区肺炎克雷伯菌ESBLs的分离率达31.1%,头孢曲松(CRO)安曲南(ATM)和头孢噻肟(CTX)头孢泊肟(CPD)、头孢他定(CAZ)作为指示剂检出率分别为97.8%、95.6%、93.4%、76.0%、65.2%;本地区产ESBLs菌株耐药基因型CTX-M-22占54.3%,CTX-M-18占41.3%,TEM61.8%,52.1%的产ESBLs肺炎克雷伯菌SHV耐药基因阳性。结论:CRO、ATM和CTX对检测ESBLs阳性率较高;CTX-M-22、CTX-M-18是本地区产ESBLs菌株的主要基因型。     

Secondary galling: a novel feeding strategy among ‘non‐pollinating’ fig wasps from Ficus curtipes

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胞外ATP对AlCl3诱导的细胞死亡过程中胞内H2O2和Ca2+水平的影响及其生理机制分析

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Tropomyosin is localized in the nuclear matrix and chromosome scaffold of physarum polycephalum

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