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21.
A spontaneous melanotic ependymoma was observed in the brain of an adult female Goeldi's marmoset (Callimico goeldii). The mass completely occupied the left lateral ventricle, rupturing the fornix and corpus callosum, and compressing the adjacent neuropil. Special histochemical techniques, including melanin bleach, periodic acid-Schiff, Perls iron and phosphotungstic acid hematoxylin, demonstrated the neoplasms to be an ependymoma with a rare melanotic differentiation. 相似文献
22.
Crystallization and preliminary X-ray diffraction studies of aSFP, a bovine seminal plasma protein with a single CUB domain architecture.
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J. M. Dias A. L. Carvalho I. Klln J. J. Calvete E. Tpfer-Petersen P. F. Varela A. Romero C. Urbanke M. J. Romo 《Protein science : a publication of the Protein Society》1997,6(3):725-727
Bovine acidic seminal fluid protein (aSFP) is a 1.29 kDa polypeptide of the spermadhesin family built by a single CUB domain architecture. The CUB domain is an extracellular module present in 16 functionally diverse proteins. To determine the three-dimensional structure of aSFP, the protein was crystallized at 21 degrees C by vapor diffusion in hanging drops, using ammonium sulfate, pH 4.7, and polyethyleneglycol 4,000 as precipitants, containing 10% dioxane to avoid the formation of clustered crystals. Elongated prismatic crystals with maximal size of 0.6 x 0.3 x 0.2 mm3 diffract to beyond 1.9 A resolution and belong to space group P2(1)2(1)2(1), with cell parameters a = 52.4 A, b = 41.5 A, c = 48.2 A. There is one aSFP molecule per asymmetric unit, which corresponds to a crystal volume per unit molecular mass of 2.04 A3/Da, and analytical ultracentrifugation analysis show that aSFP is a monomeric protein. 相似文献
23.
Wistar-derived rats were raised and maintained either on a normal- (25% casein) or on a low-protein (8% casein) diet until the age of 100 to 114 days. Both diets were isocaloric and contained an adequate supply of salts and vitamins. There were gross differences in body, brain and pituitary weight between the two groups. In addition, the brain and pituitary content of β-endorphin like immunoreactivity was lower in the protein malnourished rats, and three different forms of training (50 tone-footshock shuttle avoidance trials; 50 tones alone (habituation); 50 footshocks alone) caused a depletion of brain β-endorphin like immunoreactivity in the normal, but not in the malnourished rats. Footshock stimulation caused, in addition, a pituitary decrease and a plasma increase of β-endorphin like immunoreactivity, also restricted to the normal diet group. Performance in the habituation and in the shuttle avoidance tasks was similar in the two groups, despite the different responsiveness of their brain and pituitary β-endorphin systems to training and/or stimulation. In view of the possible involvement of these systems in learning suggested by these and by previous data, it seems likely that the neurohumoral regulation of habituation and avoidance learning may be different in rats submitted to protein malnutrition when compared to controls. 相似文献
24.
Silvia M.C. Dias João B. Fernandes José G.S. Maia Otto R. Gottlieb Hugo E. Gottlieb 《Phytochemistry》1982,21(7):1737-1740
The trunk wood of an Amazonian Aniba (Lauraceae) species contains, besides dillapiol and the benzodioxane-type neolignan eusiderin, four bicyclo(3.2.1)octanoid neolignans. These comprise representatives of the canellin-type: the known methoxycanellin-A and the novel compounds characterized as (1R, 3S, 4S, 5S, 6S, 7R)-1-allyl-4-hydroxy-3, 5-dimethoxy-7-methyl-6-(3′-methoxy-4′, 5′-methylenedioxyphenyl)-8-oxo-bicyclo(3.2.1)octane; (1R, 3S, 4S, 5S, 6S, 7R)-1-allyl-4-hydroxy-3, 5-dimethoxy-7-methyl-6-(3′, 4′, 5′-trimethoxyphenyl)-8-oxobicyclo(3.2.1)octane and (1R, 4R, 5R, 6S, 7R, 8S)-1-allyl-4, 8-dihydroxy-5-methoxy-7-methyl-6-(3′-methoxy-4′,5′-methylenedioxyphenyl)-3-oxobicyclo(3.2.1)octane. 相似文献
25.
40 pelvic preparations of rabbits (oryctolagus cuniculus) were bilaterally studied by dissection under the stereomicroscope and angiography. The arterial pattern of the pelvis, i.e. origin and branching of the umbilical, urogenital and internal pudendal arteries (visceral branches), is described. The main characteristics observed are as follows: (1) The umbilical artery is permeable in adults and gives origin to the cranial vesical artery and a caudal branch that irrigates the pelvic urogenital organs and, eventually, the rectum, with six patterns of branching in both sexes. (2) Usually, the urogenital artery is the continuation of the visceral branch of the internal iliac artery. In 1 animal, unilaterally, it arises from the median sacral artery. In 12 animals (6 bilaterally and 6 unilaterally) the urogenital artery is absent. When present, it forms two branches, a cranial and a caudal one, that irrigate of the urogenital organs in both sexes. (3) The internal pudendal artery is the direct continuation of the internal iliac artery and gives to rise to some visceral branches that irrigate the penis, bulbourethral gland and rectum (with six patterns of branching) in males, and the vagina, clitoris and rectum (with three patterns of branching) in females. 相似文献
26.
Marden A. de Alvarenga Raimundo Braz Fo Otto R. Gottlieb João P. de P. Dias Aderbal F. Magalhães Eva G. Magalhães Gouvan C. de Magalhães Mauro T. Magalhães José G.S. Maia Raquel Marques Anita J. Marsaioli Antônio A.L. Mesquita Anselmo A. de Moraes Alaide B. de Oliveira Geovane G. de Oliveira Gentil Pedreira Sebastião K. Pereira Sonildes L.V. Pinho Celira C. Santos 《Phytochemistry》1978,17(3):511-516
Wood samples, infested by fungi during storage, were shown to contain, besides the known 5-methyl-mellein, additional (3R)-8-hydroxy-3-methyl-3,4-dihydroisocoumarins substituted by 7-methyl, 5-formyl, 5-carboxy, 5-hydroxy, 5-methoxy, 6-methoxy-5-methyl and 6,7-dimethoxy-5-methyl groups, as well as 6-formyl-7-hydroxy-5-methoxy-4-methylphthalide. Several 2-methylchromanones were synthesized in order to show that this class of compounds can be distinguished from 3-methyl-3,4-dihydroisocoumarins by MS. 相似文献
27.
S O Andrade H O da Silva Lopes M de Almeida Barros G G Leite S M Dias M Saueressig D Nobre J A Temperini 《Arquivos do Instituto Biológico》1978,45(2):117-136
Aspects of photosensitization in bovines grazing on pastures of Brachiaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures 45(2):117-136, 1978. This paper reports experimental studies on photosensitization in bovines grazing on different pastures of Brachiaria decumbens Stapf in the "Cerrados" region (Planaltina, DF). Climatic conditions, zinc content and occurence of fungi on pastures were investigated. Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures examined. Photosensitization was observed in one animal maintained on a pasture of B. decumbens formed with seeds from Australia. Clinical and necropsy data were similar to those related in literature for sporidesmin-intoxicated animals. An isolate of P. chartarum and samples of bovine bile were assayed for sporidesmin presence. 相似文献
28.
Hadj S. Aoued Soma Sannigrahi Sarah C. Hunter Nandini Doshi Zakia S. Sathi Anthony W. S. Chan Hasse Walum Brian G. Dias 《Genes, Brain & Behavior》2020,19(4)
Salient sensory environments experienced by a parental generation can exert intergenerational influences on offspring. While these data provide an exciting new perspective on biological inheritance, questions remain about causes and consequences of intergenerational influences of salient sensory experience. We previously showed that exposing male mice to a salient olfactory experience, like olfactory fear conditioning, resulted in offspring demonstrating a sensitivity to the odor used to condition the paternal generation and possessing enhanced neuroanatomical representation for that odor. In this study, we first injected RNA extracted from sperm of male mice that underwent olfactory fear conditioning into naïve single‐cell zygotes and found that adults that developed from these embryos had increased sensitivity and enhanced neuroanatomical representation for the odor (Odor A) with which the paternal male had been conditioned. Next, we found that female, but not male offspring sired by males conditioned with Odor A show enhanced consolidation of a weak single‐trial Odor A + shock fear conditioning protocol. Our data provide evidence that RNA found in the paternal germline after exposure to salient sensory experiences can contribute to intergenerational influences of such experiences, and that such intergenerational influences confer an element of adaptation to the offspring. In so doing, our study of intergenerational influences of parental sensory experience adds to existing literature on intergenerational influences of parental exposures to stress and dietary manipulations and suggests that some causes (sperm RNA) and consequences (behavioral flexibility) of intergenerational influences of parental experiences may be conserved across a variety of parental experiences. 相似文献
29.
Thiago F. Rodrigues Aline M. B. Mantellatto Mariella Superina Adriano G. Chiarello 《Biological reviews of the Cambridge Philosophical Society》2020,95(1):1-21
Awareness of the natural ecological processes provided by organisms that benefit human well‐being has significantly progressed towards the goal of making conservation a mainstream value. Identifying different services and the species that provide them is a vital first step for the management and maintenance of these so‐called ecosystem services. Herein, we specifically address the armadillos, which play key functional roles in terrestrial ecosystems, including as ecosystem engineers, predators, and vectors of invertebrates and nutrients, although these roles have often been overlooked. Armadillos can control pests, disperse seeds, and be effective sentinels of potential disease outbreaks or bioindicators of environmental contaminants. They also supply important material (meat, medicines) and non‐material (learning, inspiration) contributions all over the Americas. We identify key gaps in the understanding of ecosystem services provided by armadillos and areas for future research required to clarify their functional role in terrestrial ecosystems and the services they supply. Such information will produce powerful arguments for armadillo conservation. 相似文献