武汉东湖柄裸藻(Colacium Ehr.)的研究——1.形态和分类

<正> 近几年来,在武汉东湖,每到深秋至次年初夏都出现数量较多,主要附生在枝角类和桡足类等浮游动物体表的柄裸藻属(Colacium Ehr.)植物;在冬末春初,出现种群数量的高峰。自1981年至1984年,作者曾对它进行过有关形态、分类和生态方面的探讨。在本文仅简述其有关形态和分类方面的问题。

金环蛇毒心脏毒对S180,EAC腹水癌细胞的细胞毒性作用

目的: 探讨金环蛇毒心脏毒对S180, EAC 腹水癌细胞的细胞毒作用。方法: 采用小白鼠腹腔和皮下接种S180, EAC 腹 水癌细胞造成小白鼠腹水模型后腹腔注射金环蛇毒心脏毒。结果: 腹腔注射金环蛇毒心脏毒, 能抑制肿瘤细胞的生长, 降低接 种率。但不能完全控制腹水和癌细胞的生长。体外试验表明有明显的细胞毒作用。台酚蓝染色镜检可见死细胞显著增加, 腹 水图片检查, 给药后细胞膜破裂, 纤维化坏死明显。结论: 能延长小白鼠存活时间。

金环蛇蛇毒对S180, EAC 腹水癌细胞的细胞毒性作用

　目的　探讨金环蛇毒对S180, EAC 腹水癌细胞的细胞毒性作用。　方法　采用小白鼠腹腔和皮下 接种S180, EAC 腹水癌细胞造成小白鼠腹水模型后腹腔注射金环蛇毒。　结果　腹腔注射金环蛇毒, 能 抑制肿瘤细胞的生长, 降低接种率。但不能完全控制腹水和癌细胞的生长。体外试验表明有明显的细胞毒 作用。台酚蓝染色镜检可见死细胞显著增加, 腹水图片检查给药后细胞膜破裂, 纤维化坏死明显。　结论 　能延长小白鼠存活时间。

The vertical microdistribution of cyanobacteria and green algae within desert crusts and the development of the algal crusts

Substantial amounts of algal crusts were collected from five different desert experimental sites aged 42, 34, 17, 8 and 4 years, respectively, at Shapotou ( China) and analyzed at a 0.1 mm microscale of depth. It was found that the vertical distribution of cyanobacteria and microalgae in the crusts was distinctly laminated into an inorganic-layer (ca. 0.00 - 0.02 mm, with few algae), an algae-dense-layer ( ca. 0.02 - 1.0 mm) and an algae-sparse-layer ( ca. 1.0 - 5.0 mm). It was interesting to note that in all crusts Scytonema javanicum Born et Flah ( or Nostoc sp., cyanobacterium), Desmococcus olivaceus (Pers ex Ach., green alga) Laundon and Microcoleus vaginatus Gom. ( cyanobacterium) dominated at the depth of 0.02 - 0.05, 0.05 - 0.1 and 0.1 - 1.0 mm, respectively, from the surface. Phormidium tenue Gom. ( or Lyngbya cryptovaginatus Schk., cyanobacterium) and Navicula cryptocephala Kutz.( or Hantzschia amphioxys (Ehr.) Grun. and N. cryptocephala together, diatom) dominated at the depth of 1.0 - 3.0 and 3.5 - 4.0 mm, respectively, of the crusts from the 42 and 34 year old sites. It was apparent that in more developed crusts there were more green algae and the niches of Nostoc sp., Chlorella vulgaris Beij., M. vaginatus, N. cryptocephala and fungi were nearer to the surface. If lichens and mosses accounted for less than 41.5% of the crust surface, algal biovolume was bigger when the crust was older, but the opposite was true when the cryptogams other than algae covered more than 70%. In addition to detailed species composition and biovolume, analyses of soil physicochemical properties, micromorphologies and mineral components were also performed. It was found that the concentration of organic matter and nutrients, electric conductivity, silt, clay, secondary minerals were higher and there were more micro-beddings in the older crusts than the less developed ones. Possible mechanisms for the algal vertical microdistribtion at different stages and the impact of soil topography on crust development are discussed. It is concluded that biomethods ( such as fine species distribution and biovolume) were more precise than mineralogical approaches in judging algal crust development and thus could be a better means to measure the potentiality of algal crusts in desert amelioration.

Floral surveys on Gomphonemaceae and Cymbellaceae (Bacillariophyta) from the headwaters of the Yangtze River, Qinghai, China

Gomphonemaceae and Cymbellaceae from the headwaters of the Yangtze River, Qinghai Province, China, comprised 84 taxa belonging to four genera. The dominant species were Gomphonema kaznakowi Mer., G. hedini Hust., G. olivaceum (Lyngbye) Kutz., Cymbella cistula (Ehr.) Kirchn. var. cistula and C. minuta Hilse ex Rabh. var. minuta. Some arctic and alpine forms also occurred, and the following taxa were unique to this region: C. cistula var. asiatica Mer., C. cistula var. capitata Grun., C. yabe Skvortzow var. punctata Li and Shi, G. olivaceum (Lyngbye) Kutzing var. brevistriatum Li and Shi and G. staurophorum (Pant.) Cleve-Euler var. oblongum Li and Shi. Different morphological forms of G. kaznakowi Mer. may be related to the upheaval of the plateau. Species diversity of the diatoms appears to be related not only to macro-environment (e.g., geographic zonation) but also to microhabitat and microclimate.