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51.
Developmental change in microheterogeneity of chicken serum transferrin (Tf) was investigated by polyacrylsmide-gel isoelectric focusing, direct immunofixation, and densitometry. Three main Tf species (Tf-0, Tf-1, and Tf-2, which have 0, 1, and 2 sialic acid residues per molecule, respectively) were resolved and their relative ratios were determined. As development proceeded, a relative increase occurred in the most acidic species (Tf-2) with decreases in the less acidic ones (Tf-0 and Tf-1).  相似文献   
52.
To control container-breeding mosquitoes in the small island of Minnajima (0.56 km2), northern Okinawa, Japan, laboratory-reared adults (aged 7-10 days) of Toxorhynchites splendens (Palawan strain), a mosquito with predatory larvae, were released repeatedly during 1984, 1986 and 1987. Thirteen species of mosquitoes (Diptera: Culicidae) occurred in artificial containers, ground pools or crab-holes on the island, the predominant species being Aedes (Stegomyia) albopictus and Culex (Culex) quinquefasciatus. Predatory mosquito larvae of Culex (Lutzia) fuscanus and Cx (Lt.) halifaxii were found commonly in wet containers. In the first year of study, during a period of 54 days from 13 May to 5 July 1984, totals of 879 female and 806 male adults of Tx.splendens were released on six occasions. Similarly, between 29 April and 30 August 1986, totals of 2920 female and 2878 male adult Tx.splendens were released. In the third study year, totals of 2041 female and 1783 male Tx.splendens were released on eight occasions during 199 days from 23 April to 7 November 1987. After adult releases at two sites, the immature stages of Tx.splendens were found in 164 out of 502 traps in 1984, 421 out of 933 traps in 1986, and 151 out of 502 traps in 1987. The number of immatures of Tx.splendens present in each trap varied from 1 to 40 in 1984, 1 to 29 in 1986 and 1 to 9 in 1987. Numbers of immatures of the target species found in the traps during August-September averaged 71.9/trap/month in 1984, 114.7/trap/month in 1986 and 36.0/trap/month in 1987, significantly less in the traps with Tx.splendens than in those without them. The present field studies indicated that, in this small island, approximately 250 adult female and 200 male Tx.splendens per month should be released from April to November, and the releases should be carried out every year, in order to control effectively the target mosquitoes Ae.albopictus and Cx quinquefasciatus breeding in artificial containers in Minnajima.  相似文献   
53.
54.
In the starfish, Asterias amurensis , the acrosome reaction-inducing capacity of the egg jelly has been attributed to two components in the egg jelly: a sulfated glycoprotein (ARIS) and an unidentified low-molecular weight substance (Co-ARIS). In the process of purification of Co-ARIS, we found that Co-ARIS is not a single chemical entity but a series of closely related molecules. Co-ARIS was first group-separated by using octadecylsilane and anion-exchanger. Three major Co-ARIS' (I, II and III) were then purified by successive chromatographies using octadecylsilane and silica gel to the homogeneity in thin layer chromatography. Each of purified Co-ARIS', together with ARIS or the Pronase-digest of ARIS, induced the acrosome reaction at high ratios in normal seawater.  相似文献   
55.
Chick myogenic cells grew in a medium composed of Eagle's minimum essential medium (MEM), horse serum (HS), and one of the essential factors needed for myogenic cell growth (EFMG), that is, chick embryo extract (EE), chick serum (CS), or the muscle trophic factor (MTF). But they did not grow in the absence of the EFMG. In the absence of HS, they scarcely grew in a medium composed of MEM, and EE or MTF. They grew in a medium composed of MEM and CS; they grew much better in a medium composed of MEM, CS, and HS.
In the presence of one of the EFMG, the optimal HS concentration for growth varied depending on its lot. At higher HS concentrations, growth was suppressed. Further, it was suggested that an inhibitory substance(s) for myogenic cell growth was present in HS. The inhibitory effects can usually be minimized by diluting the serum with an artificial medium.  相似文献   
56.
When the axis of castor-bean which has been fixed in a horizontalposition for some time is rotated around its longitudinal axisand is then fixed in a new horizontal position, the zone ofmucilaginous layers which was being formed (in a symmetricalcrescent shape with its thickest portion situated at the topmostpart of the xylem on the upper side), ceases further formation,and a new, less symmetrical, zone begins to form in the areawhich extends from the new upper side to the new lower one inthe direction opposite to that of rotation. The greater theangle of rotation, the further the area where the new zone ofmucilaginous layers is laid down extends; in the case wherethe horizontal axis is turned upside-down, the new zone of mucilaginouslayers is formed symmetrically in the xylem on the new upperside. Moreover, if the axis once horizontally fixed is turnedto a vertical position, the formation of mucilaginous layersstops on the old upper side and starts on the old lower one.However, formation on the lower side is soon discontinued. As a possible physiological factor for producing these results,the effect of the accommodation of protoplasm to the precedinghorizontal fixation upon the formative and metabolic responsesto the stimulation of gravitational forces is discussed.  相似文献   
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