Mediastinal Schwannoma in a horse-cytologic,histologic, and immunochemical evaluation

A 31-kg mediastinal mass from a 24-year-old horse is described. Cytologic imprints contained numerous spindle cells with indistinct cytoplasm and multiple foci of palisading nuclei. Histologic sections had these same characteristics and areas of central fibrillar material between palisading nuclei (Verocay bodies). Within histologic sections, spindle cell cytoplasm had positive immunoreactivity for vimentin and S-100, whereas immunoreactivity was not detected for desmin and cytokeratin. Cytologic, histologic, and immunochemical evaluation confirmed a diagnosis of solitary schwannoma.     

Sensitivity and specificity of cytologic evaluation in the diagnosis of neoplasia in body fluids from dogs and cats

Sensitivity and specificity were determined for the cytologic detection of malignant tumors in canine and feline body cavity effusions. In a prospective study, 424 body cavity effusions from dogs and cats were collected and evaluated, including 70 pleural and 163 peritoneal effusions from dogs, and 77 pleural and 114 peritoneal effusions from cats. Final diagnoses were confirmed in 339 of the 424 cases by clinical follow-up, necropsy, and in the case of malignant tumors, Histopathology. Malignant tumors were found in 18% of canine and 25% of feline body cavity effusions. Approximately one-half of tumors in both dogs and cats were carcinomas. Discrete cell tumors accounted for 56% of feline neoplastic effusions. The sensitivity of cytologic evaluation for the detection of malignant tumors in body cavity effusions was 64% for dogs and 61% for cats. Specificity was 99% for canine and 100% for feline effusions. Sensitivity and specificity were comparable to those obtained with cytologic evaluation of human samples.     

Malignant histiocytosis in a domestic cat: cytomorphologic and immunohistochemical features

Malignant histiocytosis (MH) was diagnosed in a 13-year-old neutered male Domestic Shorthair cat on the basis of light microscopic and immunohistochemical findings. Thoracic fluid analysis showed a modified transudate which contained a very few atypical discrete cells. Cytologic and histologic evaluation of mediastinal and splenic masses revealed a pleomorphic population of large, discrete, round cells 10 to 30 micrometers in diameter with marked cellular atypia. Nuclei were oval to reniform, often with prominent, bizarre nucleoli. Multinucleated cells and mitotic figures were commonly seen. Erythro- and leucocytophagia were noted. Immunohistochemistry indicated a scattered positive staining pattern with the histiocytic antigenic marker Mac387 and a minor population of cells showing positive reactivity for lysozyme. This report describes the characterization of MH in a cat and emphasizes that MH should be considered as a differential diagnosis in proliferative disorders of discrete-cells in this species.     

植物胚囊发育的细胞与分子生物学研究

综述了植物胚囊发育的细胞及分子生物学研究进展 ,并对该领域的进一步研究和发展提出了问题     

冬小麦1A缺体单倍体的细胞学研究

对1B/1R易位系冬小麦73(36)9-1的1A缺体单倍体小孢子母细胞和小孢子进行了细胞学观察,结果表明:①减数分裂有双线期,76.7％细胞的全部染色体都有不同形态的双线结构,而中期Ⅰ染色体配对的细胞只有41％;②末端联会较多,并靠联会较少,其分布随每个细胞二价体数目的增加而逐渐减少;③四分体时期有大量的二分体,一分体和三分体,它们进一步发育成大量的败育小孢子和少量异常小孢子;④中期Ⅰ和小孢子中有不同频率的融合细胞。     

罗汉果胚轴培养再生植株及其细胞学观察

以罗汉果胚轴为外植体,探讨了不同培养基对胚轴不定芽再生的影响,并进行了再生不定芽的细胞学观察.结果表明:胚轴在改良的MS+4 mg.L-16-BA+1 mg.L-1IAA的固体培养基中,不定芽分化平均每瓶高达7.6个;单芽段一步生根成苗.细胞学观察结果表明:不定芽和体细胞胚起源于胚轴形成的愈伤组织表层;不定根起源于愈伤组织内部.     

小麦核不育×中国春3C二体附加系后代(F1)的细胞学分析

以小麦核不育×中国春3C二体附加系杂种F1和小麦核不育×普通小麦4E单体附加系杂种F1代为材料,利用细胞学方法研究了花粉母细胞减数分裂期(中期和后期)的染色体及二分体、四分体时期的小核。结果表明,小麦核不育×中国春3C二体附加系杂种F1代在花粉母细胞减数分裂中期出现了3个单价体的染色体构型,后期出现了2个或2个以上的落后染色体,二分体、四分体时期出现了2个或2个以上的小核,在不同的核不育背景中出现的频率各不相同,说明3C染色体在小麦核不育背景中具有诱导染色体断裂的作用,但在不同的小麦核不育背景中诱导染色体断裂的作用各不相同;在小麦核不育×普通小麦4E单体附加系杂种F1代花粉母细胞减数分裂中期、后期、二分体和四分体时期也观察到了同样的结果,说明4E染色体同样具有诱导染色体断裂的作用;3C或4E染色体诱导染色体断裂可能是在花粉母细胞减数分裂的多个时期。     

诱导浙贝母多倍体的研究初报

浙贝母(Fritillaria thunbergii Miq)是二倍体植物(2n=24),本试验用不同浓度的秋水仙碱处理(野生浙贝×细叶种)F_1种子,结果表明:用0.20％秋水仙碱处理湿种子和干种子的加倍成功率最高,分别为33.62％和10.17％;变异株具有典型的多倍体特性,植株生长旺盛,叶片明显增厚,叶色深绿,叶片表皮气孔增大,根系肥大,细胞学观察结果表明;变异株的染色体数已加倍成2n=48。此外,对浙贝母倍性育种的前景进行了简略的讨论。