首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
Summary Specially in stress conditoin, some hyaline droplets occur in the perikarya of the neurosecretory hypothalamic cell of Zoarces viviparus. They first appear as filamentous macromolecular material in the intracisternal space, then tend to accumulate in the form of irregular electron dense rods or reticulum. The neurosecretory cells containing such hyaline bodies have usually few elementary neurosecretory granules and dilated endoplasmic reticulum.Aided by a Grant from NATO and the Deutsche Forschungsgemeinschaft.My thanks are due to Prof. Dr. E. Lindner and Doz. Dr. K. H. Andres for their kind help in the explanation of electronmicrographs.  相似文献   

3.
Summary The morphology and the role of the follicle cells of Viviparus viviparus were examined by means of light and electron microscopy. The follicle cells appear to contain glycogen and fat, and often lysosomes or heterogeneous inclusions. Therefore, they seem to be active in phagocytosis and storage. They are probably involved in the nutrition of the oocyte. Their role in the formation of a selectively permeable barrier is discussed.The authors thank Drs. H.H. Boer, M. de Jong-Brink and J. Wijdenes of the Free University of Amsterdam for their assistance in the translation of this paper  相似文献   

4.
Yanygina  Liubov V. 《Limnology》2020,21(1):165-171
Limnology - Alien species can have significant impacts on invaded ecosystems that include but are not limited to the reduction in biodiversity and alteration of the structure and functioning of...  相似文献   

5.
Acid phosphatases differing in both subcellular localization and substrate specificity were isolated for the first time from the liver of the freshwater snail Viviparus viviparus L. by preparative isoelectrofocusing. One of five characterized phosphatases is highly specific to ADP and the others can hydrolyze (at variable rate) a series of natural substrates. A scheme is proposed for the involvement of the studied phosphatases in carbohydrate metabolism. We have also studied some peculiarities of the effect of Cd2+ in vitro and in vivo on the activities of individual components of the acid phosphatase complex and corresponding changes in metabolism of the freshwater snail as a new test-object allowing the estimation of toxicity in water.  相似文献   

6.
Static bioassays with copper (as CuSO4 · 5H2O) were conducted in laboratory with a freshwater pond snailViviparus bengalensis, at different environmental temperatures. The 96 hr LC50 values in ppm of Cu were 0.060 at 32.5 °C; 0.066 at 24 °C; 0.09 at 27.3 °C and 0.39 at 20.3 °C. In higher copper concentrations some behavioural changes such as secretion of mucus, discharge of eggs and embryos were noted. The results indicate that toxicity to copper increases with temperature increase.  相似文献   

7.
8.
The species of the Angelica archangelica L.-group and Angelica lucida L.-group are included in Angelica L. based on morphological coincidences and simularities. Both related groups represent different section, the sect. Coelopleurum (Ledeb.) Pimen. and sect. Archangelica Regel of the genus Angelica L. The area of Angelica L. shows an holarctic distribution (fig. 1). A map and diagnoses give an idea of the distribution patterns of the species. They generally occur in mesic sites along rivers often also along the edge of forests. A. archangelica L. is divided into subsp. archangelica with var. decurrens (Ledeb.) comb. nov., f. decurrens, f. tschimganica (Korov.) comb. nov., f. komarowii (Schischk.) comb, nov., f. himalaica (Clarke) comb. nov., var. sativa (Mill.) Rikli and subsp. litoralis (Fries) Thell.  相似文献   

9.
10.
11.
12.
Johannes Rumberg 《Planta》1931,15(1-2):1-42
Ohne ZusammenfassungMit 29 Textabbildungen und Tafel I–X.  相似文献   

13.
14.
15.
16.
17.
18.
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号