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991.
Carlo Moscovici M.Giovannella Moscovici Humberto Jimenez Michael M.C. Lai Michael J. Hayman Peter K. Vogt 《Cell》1977,11(1):95-103
Several continuous tissue culture cell lines were established from methylcholanthrene-induced fibrosarcomas of Japanese quail. The lines consist either of fibroblastic elements, round refractile cells or polygonal cells. They show transformed characteristics in agar colony formation and hexose uptake, and most are tumorigenic. Their cloning efficiency in plastic dishes is not increased over that of normal quail embryo fibroblasts. The quail tumor cell lines do not produce endogenous avian oncoviruses and fail to complement the Bryan high titer strain of Rous sarcoma virus; those tested lack the p27 protein of avian oncoviruses. Most of the cell lines are susceptible to subgroup A avian sarcoma viruses, but are relatively resistant to viruses of subgroups C, E and F as compared to normal quail embryo fibroblasts. 相似文献
992.
Marke E. Swanson Thomas E. Hughes Irene St Denny Dennis S. France James R. Paterniti Jr Carlo Tapparelli Patrick Gfeller Kurt Bürki 《Transgenic research》1992,1(3):142-147
To examine the consequences of increased apolipoprotein A-I production on cholesterol and lipoprotein metabolism, we have
produced two lines of transgenic rats; one expressing moderate and one very high levels of human apolipoprotein A-I. The rats
were produced by microinjection of a 13 kbp DNA fragment containing the human apolipoprotein A-I gene plus 10 kbp of its 5′
flanking sequence and 1 kbp of its 3′ flanking sequence. Both lines of transgenic rats express human apolipoprotein A-I mRNA
in liver and human apolipoprotein A-I in plasma. Sera from these rats contain significantly higher levels of total apolipoprotein
A-I, high density lipoprotein cholesterol and phospholipid than sera from non-transgenic littermates. Transgenic rats expressing
high levels of human apolipoprotein A-I have reduced levels of serum rat apolipoprotein A-I suggesting a mechanism exists
to down-regulate apolipoprotein A-I production. These transgenic rats provide a unique animal model to examine the effects
of increased apolipoprotein A-I production on lipid and lipoprotein metabolism. 相似文献
993.
Histomorphological changes in the reproductive condition of parasitized marine planktonic copepods 总被引:1,自引:0,他引:1
Ianora A.; di Carlo B.Scottodi; Mazzocchi M.G.; Mascellaro P. 《Journal of plankton research》1990,12(2):249-258
Changes in the internal morphology of parasitized copepods sampledin the Gulf of Naples from 1986 to 1988 were investigated usingboth light and transmission electron microscopy. The most commonand devastating form of infection was due to the parasitic dinoflagellateSyndinium, which induced gross modifications in the internaland external morphology of the host population. The parasitereduced fecundity and longevity of infected individuals, whichmainly included juvenile and female populations of the copepodParacalanus parvus. Infection rates for this species were ashigh as 12% for. juveniles and 13% for adult females for theperiod investigated. Infection by the parasitic dinoflagellateBlastodinium induced less negative effects on the reproductivebiology of their hosts. This pathogen did not lead to sexualcastration and oogonal development appeared normal. Other formsof infestation were rare and included infections due to protozoa,fungi and bacteria.
*Died tragically at sea during a cruise on December 15, 1988 相似文献
994.
By Guido Frizzi Anna Lecis Carlo Contini 《Journal of Zoological Systematics and Evolutionary Research》1970,8(1):154-159
Males of Urosimulium stefanii Cont., (1963) from various populations in Sardinia, differ from females by a long asynaptic region in one pair of salivary gland chromosomes. This asynaptic tract does not seem to be due to inversions but rather to large structural changes. In meioses of the male, a pair of chromosomes does not show interstitial chiasmata. It is suggested that this pair of chromosomes represents the sex chromosome pair. The evolutionary process has been discussed. 相似文献
995.
996.
THE DEMONSTRATION OF ENZYMATIC ACTIVITY IN PINOCYTIC VESICLES OF BLOOD CAPILLARIES WITH THE ELECTRON MICROSCOPE 总被引:10,自引:7,他引:3
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In aldehyde-fixed myocardium, enzymatic activity to nucleotide substrates was localized to the pinocytic vesicles of blood capillaries with the electron microscope. No other structures of the endothelial cell showed activity under the conditions employed. These findings are discussed in relation to recent concepts of transport across the capillary wall. 相似文献
997.
998.
Gregorio Oxilia Eugenio Bortolini Giulia Marciani Jessica Cristina Menghi Sartorio Antonino Vazzana Matteo Bettuzzi Daniele Panetta Simona Arrighi Federica Badino Carla Figus Federico Lugli Matteo Romandini Sara Silvestrini Rita Sorrentino Adriana Moroni Carlo Donadio Maria Pia Morigi Viviane Slon Marcello Piperno Sahra Talamo Carmine Collina Stefano Benazzi 《American journal of physical anthropology》2022,179(1):18-30
999.
Pulido Mantas Torcuato Pola Lisa Cerrano Carlo Gambi Maria Cristina Calcinai Barbara 《Hydrobiologia》2022,849(8):1969-1980
Hydrobiologia - Considering the pivotal role played by erosive organisms in the marine habitat and the scanty knowledge of this phenomenon in the Mediterranean Sea, the present study aimed to... 相似文献
1000.
Pagotto João Paulo Alves Pessoa Leonardo Antunes Goulart Erivelto Mise Fábio Teruo Ortega Jean Carlo Gonçalves Landgraf Guilherme Okuda 《Hydrobiologia》2022,849(10):2299-2316
Hydrobiologia - Human activities change the environmental conditions of streams and alter their assemblages. However, the environmental factors associated with the change in the ecomorphological... 相似文献