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111.
Ganoderma microsporum immunomodulatory protein induces apoptosis and potentiates mitomycin C‐induced apoptosis in urinary bladder urothelial carcinoma cells 下载免费PDF全文
112.
Synonymous substitution rates have been shown to vary among evolutionary
lineages of both nuclear and organellar genes across a broad range of
taxonomic groups. In animals, rate heterogeneity does not appear to be
correlated across nuclear and mitochondrial genes. In this paper, we
contrast substitution rates in two plant groups and show that grasses
evolve more rapidly than palms at synonymous sites in a mitochondrial, a
nuclear, and a plastid gene. Furthermore, we show that the relative rates
of synonymous substitution between grasses and palms are similar at the
three loci. The correlation in synonymous substitution rates across genes
is particularly striking because the three genes evolve at very different
absolute rates. In contrast, relative rates of nonsynonymous substitution
are not conserved among the three genes.
相似文献
113.
K C Lowe N F Beck D C McNaughton C A Jansen A L Thomas P W Nathanielsz K Mallon D H Steven 《Quarterly journal of experimental physiology and cognate medical sciences》1979,64(4):253-262
The fine structural appearance of the placenta of the ewe has been examined following long-term infusion of CB154 into either the fetus or the pregnant ewe. Binucleate cells which usually contain aggregations of spherical membrane-bound electron-dense inclusions, are a characteristic component of the chorionic epithelium of the sheep. Following CB154 infusion into either the fetus or ewe at 111 to 137 days of gestation, binucleate cells were partially or completely depleted of the droplets which are present in binucleate cells of control animals at a similar gestational age. No obvious changes in the maternal epithelial syncytium were observed after CB154 administration. Infusion of CB154 into the fetus alone was also followed by degenerative changes in some binucleate cells which ranged from condensation of nuclei to complete cell fragmentation. Either a direct or an indirect action of CB154 on binucleate cells is suggested by these observations. Hypoprolactinaemia followed CB154 infusion in all treated animals; its possible influence on binucleate cell activity is discussed. 相似文献
114.
D H Steven L B Jeffcott K A Mallon S W Ricketts P D Rossdale C A Samuel 《Journal of reproduction and fertility. Supplement》1979,(27):579-586
Post-partum placentae and uterine biopsy samples from mares after normal and abnormal foalings are described. After normal delivery there is little damage to fetal or maternal tissues. The villous epitheliochorial palcenta separates cleanly at the maternal-fetal interface and the afterbirth consists almost exclusively of fetal tissue. Uterine involution is well advanced by the 3rd and 4th days post partum and the changes are usually complete by the oestrus 7--10 days after parturition. Placental separation and involution of the uterus appear to proceed normally in malpresented foals and in otherwise viable foals with musculoskeletal defects. In aborted, stillborn or dysmature foals there are obvious signs of damage to both fetal and maternal tissues. It is generally accepted that the growth and development of the fetus is dependent upon a placenta of adequate functional capabilities. The observations suggest that the placenta is similarly dependent upon its association with a normal healthy fetus. 相似文献
115.
Eva Lana-Elola Heather Cater Sheona Watson-Scales Simon Greenaway Jennifer Müller-Winkler Dorota Gibbins Mihaela Nemes Amy Slender Tertius Hough Piia Keskivali-Bond Cheryl L. Scudamore Eleanor Herbert Gareth T. Banks Helene Mobbs Tara Canonica Justin Tosh Suzanna Noy Miriam Llorian Patrick M. Nolan Julian L. Griffin Mark Good Michelle Simon Ann-Marie Mallon Sara Wells Elizabeth M. C. Fisher Victor L. J. Tybulewicz 《Disease models & mechanisms》2021,14(10)
116.
Recent ecological studies in invertebrates show that the outcome of an infection is dependent on the specific pairing of host and parasite. Such specificity contrasts the long-held view that invertebrate innate immunity depends on a broad-spectrum recognition system. An important question is whether this specificity is due to the immune response rather than some other interplay between host and parasite genotypes. By measuring the expression of putative bumblebee homologues of antimicrobial peptides in response to infection by their gut trypanosome Crithidia bombi, we demonstrate that expression differences are associated with the specific interactions. 相似文献
117.
118.
Megaherbivorous dinosaur coexistence on the Late Cretaceous island continent of Laramidia has long puzzled researchers, owing to the mystery of how so many large herbivores (6–8 sympatric species, in many instances) could coexist on such a small (4–7 million km2) landmass. Various explanations have been put forth, one of which–dietary niche partitioning–forms the focus of this study. Here, we apply traditional morphometric methods to the skulls of megaherbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta to infer the ecomorphology of these animals and to test the niche partitioning hypothesis. We find evidence for niche partitioning not only among contemporaneous ankylosaurs, ceratopsids, and hadrosaurids, but also within these clades at the family and subfamily levels. Consubfamilial ceratopsids and hadrosaurids differ insignificantly in their inferred ecomorphologies, which may explain why they rarely overlap stratigraphically: interspecific competition prevented their coexistence. 相似文献
119.
120.
Chromatophore membrane formation was induced in low-aeration suspensions of Rhodopseudomonas sphaeroides and highly purified chromatophore preparations were isolated at various intervals between 4 and 18 h. The levels of several functional components associated with the isolated structures were investigated. B-875, the light-harvesting bacteriochlorophyll complex associated with the reaction center, was preferentially inserted into the chromatophore membrane during the early stages of induction, and thereafter its levels reached a steady state; b- and c-type cytochromes were also maintained at essentially constant levels. In contrast, the levels of B-850, the accessory light-harvesting bacteriochlorophyll, together with its associated protein, continued to increase throughout the induction process. Increases in the levels of the major carotenoid component followed a similar course. These findings are consistent with a stepwise assembly mechanism for associated bacteriochlorophyll and protein components and suggest that separate regulatory mechanisms control the levels of functionally essential and accessory components within the membrane. 相似文献