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101.
RNA metabolism in tracheal epithelium: alteration in hamsters deficient in vitamin A 总被引:4,自引:0,他引:4
D G Kaufman M S Baker J M Smith W R Henderson C C Harris M B Sporn U Saffiotti 《Science (New York, N.Y.)》1972,177(54):1105-1108
The electrophoretic pattern of RNA molecules that are synthesized in vitro in tracheal epithelium from hamsters deficient in vitamin A differs from that of RNA synthesized in normal, pair-fed control hamsters. There is less RNA of low electrophoretic mobility in the epithelial cells deficient in vitamin A. This alteration is reversed after the deficient animals have been treated with vitamin A. 相似文献
102.
PE Fernández ME Diessler A Pachame HH Ortega EJ Gimeno EL Portiansky CG Barbeito 《Reproduction in domestic animals》2014,49(2):263-269
The aim of this study was to characterize cytoskeletal intermediate filament proteins and glycoconjugates of syncytiotrophoblast, cytotrophoblast and decidual cells of feline endotheliochorial placenta. Samples from 12 normal pregnant female cats, after 45 ± 5 days of gestation, were obtained removing the uterine horns by hysterectomy. Sections were processed for routine observation and for immunohistochemistry using anticytokeratin, antivimentin and antidesmin antibodies. In addition, lectin histochemistry was performed using a panel of several biotinylated lectins to characterize glycosides expression profile. Cytotrophoblast and syncytiotrophoblast showed immunoreactivity only with acidic and basic cytokeratins. Decidual cells were only positive to vimentin, consistent with their origin from endometrial fibroblasts. Trophoblast expressed a broad population of glycans, highly exposing terminal N‐acetyl glucosamine residues and non‐sialylated galactose and N‐acetyl galactosamine oligomers. Oligosaccharides bound by Phaseolus vulgaris erythroagglutinin were the only highly branched N‐linked residues evidenced in cats, and they were restricted to the syncytium. Unlike results reported on humans, mice and rats on lectin affinity of decidual cells, sialid acids and complex N‐linked oligosaccharides were not demonstrated in cats. Glycosylation of proteins determines many of their final properties, thus becoming essential for the embryo‐maternal dialogue during implantation and placentation. Changes in glycosylation pattern have been related to pathological pregnancies in other species. Hence, the knowledge about glycosylation profile of the normal cat placenta may lead to a better understanding of both normal and pathological reproductive events. 相似文献
103.
LYNNE A. SNOW DVM RICK WHITE DVM SCOTT GUSTAFSON DVM MS Diplomate ACVS LIN XIE BS GISELLE HOSGOOD BVSc MS PhD Diplomate ACVS W. TODD MONROE PhD PE JOHN P. CASEY BS MANDI J. LOPEZ DVM MS PhD Diplomate ACVS 《Veterinary surgery : VS》2010,39(2):195-207
Objective— To quantify and compare canine stifle stability after 3 stabilization techniques. Study Design— Randomized controlled study. Sample Population— Adult canine cadaveric pelvic limbs. Methods— Total craniocaudal (CrCa) tibial translation quantified in stifles with the cranial cruciate ligament (CrCL) intact, transected, and stabilized with 1 of 3 techniques: (1) hamstring graft (HG); (2) modified retinacular imbrication (MRIT); (3) anatometric fascia lata translocation (AFLT). Tibial translation was quantified from radiographs generated during application of cranial and caudal forces to the tibia. After removal of all soft tissues except periarticular ligaments and fixation, CrCa tibial translation, as before, and medial–lateral rotation, via torsional loading, was quantified with an active motion analysis system. Total tibial translation was evaluated for effect of technique and cruciate status using mixed effect linear model with significance considered at P‐value <.05. Results— CrCa translation was not significantly different across stabilization techniques with CrCLs intact, transected, or after stabilization. Poststabilization translation was significantly less than posttransection for all techniques. Compared with the intact CrCL, CrCa translation poststabilization after HG was significantly greater whereas poststabilization after MRIT and AFLT was not significantly different. Tibial rotation exceeded instrumentation limits in 62.5% HG limbs, 20% MRIT limbs, and 60% AFLT limbs. Conclusions— All 3 stifle stabilization techniques confer comparable CrCa translational stability after CrCL disruption with that provided by the MRIT and AFLT techniques comparable to the intact CrCL. Clinical Relevance— The extra‐ and intracapsular techniques evaluated in this study reduced CrCa tibial translation in CrCL deficient stifles to varying amounts. 相似文献
104.
A 10-year evaluation of the functional basis for regeneration habitat preference of trees in an African evergreen forest 总被引:2,自引:0,他引:2
Colin A. Chapman Kaoru Kitajima Amy E. Zanne Les S. Kaufman Michael J. Lawes 《Forest Ecology and Management》2008,255(11):3790-3796
The spatial distribution of tree juveniles in relation to light environments may reflect species differences in growth, survival, and functional traits and will shape the nature of forest regeneration. Long-term field experiments are important to evaluate this issue because of the potentially very long juvenile period in trees. Here, we combine a 10-year seedling survival–growth data with the results of community ordination and multivariate analyses of functional traits to ask how observed juvenile light guilds are related to species functional traits and seedling performance. We transplanted seedlings at a standardized height of 11 cm into the shaded understory and quantified their growth and survival for 10-years. Using the community-wide stem distribution data, we categorized 33 species including the focal 11 species to understory vs. gap/edge guilds. Then, we determined differences between the two guilds in seedling survival, growth, as well as seed size, adult height, and a series of leaf traits, including toughness and chemical traits (fiber, protein, phenolics, tannins, alkaloids, saponins). Among the 11 non-pioneer species whose seedlings were planted into the understory, there was no significant difference in 10-year survival between light guilds, but species in gap/edge guild tended to achieve greater height than species in the understory guild. The leaf chemical traits of 33 species did not differ between the two juvenile light guilds, but gap/edge species had smaller seeds, taller adults, and tougher leaves than understory species. We used logistic regression as a complementary approach to assess the extent to which plant traits varied between light guilds and the most parsimonious model based on AICc ranking included only leaf toughness and had an Akaike weight of 0.52. In addition, across the 11 species planted as seedlings, these traits were not significantly related to survivorship or growth over 10 years. A Principle Components Analysis illustrated associations among traits. We conclude that light guilds in terms of juvenile stem distribution could not be explained by long-term field performance of post-establishment seedlings alone. Earlier seedling stage or later sapling stage may be more important in differentiation of light guilds. For the species examined difference in growth rates could be linked to seed size and adult stature, but not to the adult leaf chemical traits considered. These results suggest the importance of examining ontogenetic shifts and relationships among functional traits for a better understanding of regeneration strategies of tropical trees. 相似文献
105.
106.
Recurrent herpes in the rabbit and man 总被引:11,自引:0,他引:11
Herpesvirus was present in secretory glands and frequently in tears of rabbits with recurrent herpetic keratitis even in the absence of corneal lesions. In normal people, herpesvirus could be cultured from saliva and tears. Chronic virus multiplication in structures such as the lacrimal and salivary glands, rather than latency, may cause recurrent herpetic disease. 相似文献
107.
“楚源果业”(长沙楚源果业有限公司的简称)从2003年起开始实施湖南省优质鲜食猕猴桃产业化工程。公司按照产业化经营的思路和集中成片、规模发展的原则,选择丰悦、翠玉等优良品种,在省内旅游区周边交通便利、农业生产管理水平较高的中低海拔地区建立生产基地,并以公司为龙头,按行业协作组织的形式将各生产基地组织起来,统一技术管理和果品营销。现已建立产业化基地约200hm^2,并在湘中、湘北、湘西北及湘西建立了鲜食猕猴桃重点示范基地。两年来,湖南省优质鲜食猕猴桃产业化开发从无到有,从小到大,极大地促进了湖南省猕猴桃产业的整体发展。 相似文献
108.
Systemic candidiasis, with involvement of the spleen, liver, kidneys, and lymph nodes, was diagnosed in a geriatric captive cheetah (Acinonyx jubatus). The animal had a long clinical history of intermittent chronic gastritis associated with Helicobacter acinonyx and chronic renal failure, both of which were repeatedly treated with broad-spectrum antimicrobial therapy. Following euthanasia, a postmortem examination showed numerous microabscesses and granulomas composed of degenerate eosinophils and containing asteroids or Splendore-Hoeppli material throughout the body. Yeast, pseudohyphae, and infrequently branching septate hyphae, demonstrated with special stains, were identified as a Candida sp. by fluorescent antibody testing. Low genetic variation in cheetahs may increase their susceptibility to infectious agents. Additional factors contributing to the overgrowth and dissemination of Candida sp. in this case may have included changes in the bacterial flora of the alimentary tract as a result of repeated antimicrobial therapy and alterations in the topography of the alimentary mucosa caused by chronic gastritis. 相似文献
109.
Atomic force microscopy was used to characterize the sliding of molybdenum oxide (MoO3) nanocrystals on single-crystal molybdenum disulfide (MoS2) surfaces. Highly anisotropic friction was observed whereby MoO3 nanocrystals moved only along specific directions of the MoS2 surface lattice. The energy per unit area to move the MoO3 nanocrystals along their preferred sliding direction was an order of magnitude less than required to slide macroscopic MoS2-bearing contacts. This extreme friction anisotropy was exploited to fabricate multicomponent MoO3 nanostructures. These reversibly interlocking structures could serve as the basis for devices such as mechanical logic gates. 相似文献
110.