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排序方式: 共有291条查询结果,搜索用时 31 毫秒
81.
Neiger R Witt AL Noble A German AJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(2):160-164
Hyperadrenocorticism is a rare syndrome in cats. Current medical therapy is unsatisfactory and prognosis for long-term survival with surgical treatment is guarded. We report on 5 cats treated with the 3-beta hydroxysteroid dehydrogenase inhibitor trilostane. Diagnosis was confirmed in all cats by endocrine testing. Three cats had concurrent diabetes mellitus. Trilostane reduced clinical signs and improved endocrine test results in all cats, but insulin requirements did not change and all continued to have some signs of hypercortisolemia. Two died or were euthanized after 16 and 140 days, whereas 3 were still alive 6, 11, and 20 months after the start of trilostane therapy. Trilostane ameliorates clinical signs of feline hyperadrenocorticism, but more research is needed before it can be recommended for treatment. 相似文献
82.
G Pugliesi ML Oliveria SC Scolari E Lopes FV Pinaffi BT Miagawa YN Paiva JRG Maio GP Nogueira M Binelli 《Reproduction in domestic animals》2014,49(1):85-91
Strategic supplementation of P4 may be used to increase conception rates in cattle, but timing of supplementation in relation to ovulation, mass of supplementary P4 and formulation of the P4‐containing supplement has not been determined for beef cattle. Effects of supplementation of long‐acting progesterone (P4) on Days 2 or 3 post‐ovulation on development, function and regression of corpus luteum (CL) were studied in beef cattle. Cows were synchronized with an oestradiol/P4‐based protocol and treated with 150 or 300 mg of long‐acting P4 on Day 2 or 3 post‐ovulation (6–7 cows/group). Colour‐doppler ultrasound scanning and blood sample collection were performed from Day 2–21.5. Plasma P4 concentrations were greater (p < 0.05) from Day 2.5–5.5 in the Day 2‐treated groups and from Day 3.5–5.5 in the Day 3‐treated cows than in the control group. CL area and blood flow during Day 2–8.5 did not differ (p > 0.05) among groups, suggesting no effect of P4 treatment on luteal development. The frequency of cows that began luteolysis before Day 15 was greater (p < 0.04) in cows treated with 300 mg than in the controls, but there were no differences between non‐treated and 150 mg‐treated cows. The interval from pre‐treatment ovulation to functional and structural luteolysis was shorter (p < 0.01) in the combined P4‐treated groups than in the control cows. In conclusion, was showed for the first time that long‐acting P4 supplementation on Day 2 or 3 post‐ovulation increases P4 concentrations for ≥3 day, has no effect on luteal development, but anticipates the beginning of luteolysis in beef cattle. 相似文献
83.
Combined data derived from clinical, cytogenetic, and blood-grouping studies of one family suggest that the MN locus is on the long arm of either the No. 2 or the No. 4 chromosome. 相似文献
84.
Kohler E Keysers C Umiltà MA Fogassi L Gallese V Rizzolatti G 《Science (New York, N.Y.)》2002,297(5582):846-848
Many object-related actions can be recognized by their sound. We found neurons in monkey premotor cortex that discharge when the animal performs a specific action and when it hears the related sound. Most of the neurons also discharge when the monkey observes the same action. These audiovisual mirror neurons code actions independently of whether these actions are performed, heard, or seen. This discovery in the monkey homolog of Broca's area might shed light on the origin of language: audiovisual mirror neurons code abstract contents-the meaning of actions-and have the auditory access typical of human language to these contents. 相似文献
85.
Leonard JA Wayne RK Wheeler J Valadez R Guillén S Vilà C 《Science (New York, N.Y.)》2002,298(5598):1613-1616
Mitochondrial DNA sequences isolated from ancient dog remains from Latin America and Alaska showed that native American dogs originated from multiple Old World lineages of dogs that accompanied late Pleistocene humans across the Bering Strait. One clade of dog sequences was unique to the New World, which is consistent with a period of geographic isolation. This unique clade was absent from a large sample of modern dogs, which implies that European colonists systematically discouraged the breeding of native American dogs. 相似文献
86.
Turrà D 《浙江大学学报(农业与生命科学版)》2004,30(4):449-449
The molecular factors involved in the three-way interaction between plant, pathogenic fungi and antagonistic/biocontrol fungi, such as Trichoderma, are still poorly understood, even if they represent a matter of interest for improving crop management and developing new strategies for plant diseases control. The aim of this work is to investigate the components involved in this interaction and, for this purpose, a proteomic approach was used. 2-D maps of the protein extracts from the single co… 相似文献
87.
Lenz G Davis RE Ngo VN Lam L George TC Wright GW Dave SS Zhao H Xu W Rosenwald A Ott G Muller-Hermelink HK Gascoyne RD Connors JM Rimsza LM Campo E Jaffe ES Delabie J Smeland EB Fisher RI Chan WC Staudt LM 《Science (New York, N.Y.)》2008,319(5870):1676-1679
Diffuse large B cell lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma. In the least curable (ABC) subtype of DLBCL, survival of the malignant cells is dependent on constitutive activation of the nuclear factor-kappaB (NF-kappaB) signaling pathway. In normal B cells, antigen receptor-induced NF-kappaB activation requires CARD11, a cytoplasmic scaffolding protein. To determine whether CARD11 contributes to tumorigenesis, we sequenced the CARD11 gene in human DLBCL tumors. We detected missense mutations in 7 of 73 ABC DLBCL biopsies (9.6%), all within exons encoding the coiled-coil domain. Experimental introduction of CARD11 coiled-coil domain mutants into lymphoma cell lines resulted in constitutive NF-kappaB activation and enhanced NF-kappaB activity upon antigen receptor stimulation. These results demonstrate that CARD11 is a bona fide oncogenein DLBCL, providing a genetic rationale for the development of pharmacological inhibitors of the CARD11 pathway for DLBCL therapy. 相似文献
88.
Surface-generated mesoscale eddies transport deep-sea products from hydrothermal vents 总被引:1,自引:0,他引:1
Adams DK McGillicuddy DJ Zamudio L Thurnherr AM Liang X Rouxel O German CR Mullineaux LS 《Science (New York, N.Y.)》2011,332(6029):580-583
Atmospheric forcing, which is known to have a strong influence on surface ocean dynamics and production, is typically not considered in studies of the deep sea. Our observations and models demonstrate an unexpected influence of surface-generated mesoscale eddies in the transport of hydrothermal vent efflux and of vent larvae away from the northern East Pacific Rise. Transport by these deep-reaching eddies provides a mechanism for spreading the hydrothermal chemical and heat flux into the deep-ocean interior and for dispersing propagules hundreds of kilometers between isolated and ephemeral communities. Because the eddies interacting with the East Pacific Rise are formed seasonally and are sensitive to phenomena such as El Ni?o, they have the potential to introduce seasonal to interannual atmospheric variations into the deep sea. 相似文献
89.
Vapor-deposited amorphous solid and hyperquenched glassy water were found to irreversibly transform, on compression at 77 kelvin, to a high-density amorphous solid. On heating at atmospheric pressure, this solid became viscous water (water B), with a reversible glass-liquid transition onset at 129 +/- 2 kelvin. A different form of viscous water (water A) was formed by heating the uncompressed vapor-deposited amorphous solid and hyperquenched liquid water. On thermal cycling up to 148 kelvin, water B remained kinetically and thermodynamically distinct from water A. The occurrence of these two states, which do not interconvert, helps explain both the configurational relaxation of water and stress-induced amorphization. 相似文献
90.
L. German Hussein Mansoor Getachew Alemu Waga Mazengia T. Amede A. Stroud 《Agricultural Systems》2007
This paper focuses on the conceptual evolution of watershed management within the context of an action research program operating in the highlands of eastern Africa, as informed by both theory and practice. Following a review of the watershed management literature, and brief program and methodological overviews, the paper explores in detail the concepts of “participation” and “integration” in watershed management. Conceptual and methodological dimensions of the terms are discussed in the context of a watershed implementation process, clarifying how “watershed issues” are defined by local users, how “stakeholders” are defined with respect to those issues, and how participation and integration may be operationalized in practice. Data are selectively chosen from different pilot sites to illustrate how concepts underlying watershed management have been refined, and methods improved. It is clear that “participation” in problem diagnosis and program implementation must move beyond community-level fora to socially-disaggregated processes and explicit management of trade-offs to diverse groups. Secondly, integration does not come about through implementation of parallel interventions, but rather through an explicit analysis of potential trade-offs and synergies of interventions to diverse system components, and strategies to define and reach systems-level goals. Each approach requires attention to ways to optimize returns to diverse social groups and system components while minimizing negative spin-offs. The paper concludes with a discussion of implications for agricultural research and development in the eastern African region. 相似文献