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.
A comparative study of % fat was carried out on Nepali children (Ranging from 6 to 18 years old) to clarify the cause of obesity attended with modernization. 126 males and 79 females who have a natural living style, in rural district (KV) and 166 males and 133 who have a living style affected by the rapid urbanization, in suburban district (BV) were selected as subjects. %Fat was estimated from skinfold thickness according to the method of Nagamine (1975). The results summarized as follows. 1) Mean %Fat of BV in each age were clearly higher than those of KV with coincidental age, especially in male subjects. 2) According to the previous reports (Yoshimizu et al., 1990; Ito et al., 1989), it's considered physical activities in the subjects of BV were lower than those of the subjects in KV. But we could not found the nutritional factors to explain the difference of % fat between BV and KV. From these results, it's considered the difference of % fat in both districts is due to the difference of their physical activities.  相似文献   

2.
The irregular echinoids Plesiechinus ornatus (Buckman) (Pygasteroida) and Galeropygus agariciformis (Forbes) (Cassiduloida) occur together in beds of the murchisonoe Zone, Bajocian, outcropping in the Cheltenham region of Gloucestershire. These species were largely restricted to different lithofacies within the carbonate shelf environment. Both adopted a hidden mode of life but achieved this by different techniques. Plesiechinus had fairly short spines and strongly muscular podia over the whole corona and was able to cover itself with coarse substrate particles. The oral tubercles are bilaterally symmetrical and are radially arranged. The oral spines are thought to have pulled sediment out from beneath the test, excavating a small depression for it. Galeropygus bore a dense covering of very small spines and its tube feet were differentiated into aboral respiratory podia and oral suckered podia. It had a preferred anterior direction of locomotion and is thought to have buried itself completely by excavating and ploughing into the substrate as it moved forward. Plesiechinus fed using only its lantern and postulated peristomial tube feet, whereas Galeropygus was a continugus sediment swallower and used its phyllode tube feet and peristomal lip spines in transferring particles towards the mouth.  相似文献   

3.
The insect fat body plays major roles in the intermediary metabolism, in the storage and transport of haemolymph compounds and in the innate immunity. Here, the overall structure of the fat body of five species of mosquitoes (Aedes albopictus, Aedes fluviatilis, Culex quinquefasciatus, Anopheles aquasalis and Anopheles darlingi) was compared through light, scanning and transmission electron microscopy. Generally for mosquitoes, the fat body consists of lobes projecting into the haemocoel and is formed by great cell masses consisting of trophocytes and oenocytes. Trophocytes are rich in lipid droplets and protein granules. Interestingly, brown pigment granules, likely ommochromes, were found exclusively in the trophocytes located within the thorax and near the dorsal integument of Anopheles, which is suggestive of the role these cells play in detoxification via ommochrome storage. This study provides a detailed comparative analysis of the fat body in five different mosquito species and represents a significant contribution towards the understanding of the structural-functional relationships associated with this organ.  相似文献   

4.
E. Rebollo  P. Arana 《Chromosoma》1995,104(1):56-67
Orientational movements and modes of segregation at anaphase I were analyzed in three different types of univalents in living spermatocytes of the grasshopper species Eyprepocnemis plorans, namely the sex univalent, three types of accessory chromosomes and spontaneous and induced autosomal univalents. When two or more univalents were present in the same spindle, their dynamics were directly compared. Chromosomes may show variable velocity and number of reorientations: the X and the most common B types (B1 and B2) are slow and rarely reorient, a more geographically restricted B (B5) is faster and reorients more often, and autosomal univalents are the fastest and show the highest frequency of reorientations. Nonetheless, the X and the accessories are rigorously reductional at anaphase I whereas autosomal univalents often fail to migrate or divide equationally. This indicates that orientational and segregational behavior are controlled mainly by chromosomal rather than cellular characteristics and that chromosomes may display a great variety of strategies to achieve regular segregation.  相似文献   

5.
Summary The kinetics of fluoresceindiacetate (FDA)-hydrolysis in erythrocytes, CHO-cells and homogenized cells was investigated by means of fluorescence spectroscopy. At a 10–6 m FDA concentration the enzymatic conversion in the homogenized cells can be described by first order reactions. When studying intact cells, total kinetics requires the addition of a first order transport term. Consequently, the total hydrolytic process can be described by three exponentials. The following model was set up on the basis of the data obtained: FDA, which exists in two sterically differing conformations, reaches the cell via an active transport mechanism, where the two conformations are converted at different rates into fluorescein by an enzymatic reaction. Intracellular FDA-enrichment factors of 100–600 were derived. In addition, the action of chemical inhibitors and of elevated temperatures on the individual reaction steps was investigated.  相似文献   

6.
7.
The distribution of actin in proteose peptone-elicited murine peritoneal macrophages is examined with fluorescent analog cytochemistry (FAC), immunofluorescence, and electron microscopy (EM). Living adherent macrophages, microinjected with 5- iodoacetamidofluorescence-labeled actin, show a rather uniform distribution of actin with punctuate and linear fluorescence in the thin peripheral areas of the cell. Apparent incorporation of a portion of linear fluorescence in the thin peripheral areas of the cell. Apparent incorporation of a portion of the microinjected actin into the cell’s actin cytoskeleton is also demonstrated when microinjected cells are subsequently examined for fluorescein fluorescence after fixation and extraction. However, a substantial perinuclear pool of actin, observed with FAC, is lost when microinjected cells are prepared for immunofluorescence using standard fixation methods. These results suggest that part of the cellular actin, possibly nonfilamentous or oligomeric, can be extracted during the normal preparative steps for immunofluorescence. When the dynamic distributin of actin structures is examined in living cells, extension of the cell’s periphery is associated with the formation of punctuate structures. The distribution of the most stable, nonextractable actin structures in fixed cells at different stages of spreading is quantified using rhodamine-labeled phalloidin and antiactin indirect immunofluorescence. At early stages, the rounded cells show cortical bands of fluorescence surrounding the nuclear region with punctuate structures directly above the plane of the attached plasma membrane. At later time periods, fully spread cells contain both punctuate and linear fluorescent structures. Adherent macrophage membranes, a preparation in which the attached membrane and membrane-cortex are isolated by shearing away the unattached plasma membrane and underlying cytoplasm, show punctuate and linear fluorescence when stained with rhodamine-labeled phalloidin. When the same cell remnant is negatively stained and examined with EM, the fluorescent punctuate structures coincide with electron-dense foci and associated radiating thin filaments. We suggest that the optimal approach for elucidating the distribution of cytoskeletal and contractile proteins involved in motile processes is a combined approach using all three techniques. Although each technique is subject to potential artifacts and limitations, the use of FAC can permit the visualization of both the soluble and stabilized components of the cytoskeleton in living, functional cells. A qualitative method for determining differences in local concentrations of proteins is also presented.  相似文献   

8.
9.
10.
11.
Summary Interspecific relationship studies between A, S and D genome diploid species, and between AAGG and AABB allotetraploid species of the genus Triticum were conducted using isoenzymatic characters located in dry mature seeds. Data was analyzed by the factorial analysis of correspondences, and dendograms were obtained by two different genetic distances. The discussion of results was based on the limitations of the study, intraspecific variability differences, isoperoxidase frequency differences and chromosomal location of peroxidases in T. aestivum cv. Chinese Spring. The closest relationship was found between dicoccoides and carthlicum. Relationships found between T. turgidum L. and T. timopheevvi Zhuk., both allotetraploid species and boeoticum; this species and speltoides; tauschi and searsii, and the last two species with bicorne, are discussed at the phylogenetic level.  相似文献   

12.
13.
A comparative study on glyoxalase II from vertebrata   总被引:1,自引:0,他引:1  
S-2-hydroxyacylglutathione hydrolase (glyoxalase II) from the liver of animals belonging to the various vertebrate classes (Oryctolagus cuniculus, Gallus gallus, Python molurus, Rana esculenta, Esox lucius) have been purified from 100,000 g supernatants of liver homogenates, using acetone fractionation and affinity chromatography. Subsequent comparative studies were concerned with some molecular and kinetic properties. Isoelectric focusing gave evidence for a single form of liver glyoxalase II in O. cuniculus, P. molurus and E. lucius, while the enzyme from G. gallus and R. esculenta showed respectively two and three forms with different pI values. All studied enzymes are basic proteins. The relative molecular mass values range from 18,000 to 23,000. The various glyoxalases II do not display markedly different Kn or Ki values. Their stability behavior at different temperatures is also quite similar.  相似文献   

14.
A comparative study of wound healing   总被引:1,自引:0,他引:1  
  相似文献   

15.
A comparative study of tryptophan catabolism   总被引:1,自引:0,他引:1  
  相似文献   

16.
17.
18.
The patterns of monosaccharide distribution of the mucilages of Cycadales are characteristic at the generic level. Arabinose, fucose, galactose, mannose, rhamnose and methylrhamnose were identified in the hydrolysed mucilage of Bowenia, Ceratozamia, Cycas, Dioon, Encephalartos, Lepidozamia, Macrozamia, Microcycas and Zamia. Stangeria contains no rhamnose and methylrhamnose, and Ceratozamia contains galactose only in traces. American genera may easily be distinguished from the others by means of their different monosaccharide composition. Lepidozamia appears to be well separated from Macrozamia.  相似文献   

19.
利用113份芥菜型油菜,运用典范相关分析方法,对西藏及周边地区芥菜型油菜的产量性状、主茎性状、分枝性状、角果性状等4组性状间的典范相关关系进行了比较研究。结果表明:(1)所研究的18个性状中,西藏芥菜型油菜的均值为周边地区芥菜型油菜的1.88倍,总体变异系数比周边省份芥菜型油菜高10.22%;(2)西藏芥菜型油菜单株产量主要取决于每株角果数和千粒重,而周边省份芥菜型油菜单株产量主要取决于每株有效角果数,中国周边国家芥菜型油菜单株产量主要取决于每株有效角果数、千粒重;(3)影响西藏芥菜型油菜产量性状最重要的因素是角果性状,其次是分枝性状和主茎性状,而影响周边省份和中国周边国家芥菜型油菜产量性状最重要的因素则是主茎性状,其次是分枝性状和角果性状;(4)西藏芥菜型油菜4组性状间极显著或显著相关的典型变量累计有9对性状,周边省份芥菜型油菜有8对性状,中国周边国家芥菜型油菜有5对性状,西藏与周边省份和中国周边国家芥菜型油菜生态性状间既有密切联系,亦略不同。  相似文献   

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