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排序方式: 共有416条查询结果,搜索用时 281 毫秒
1.
M D Pérez Alenza E Tabanera L Pe?a 《Journal of the American Veterinary Medical Association》2001,219(8):1110-1114
OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs. 相似文献
2.
Behaviour of bentazon as influenced by water and tillage management in rice‐growing conditions 下载免费PDF全文
Antonio López‐Piñeiro David Peña Ángel Albarrán Javier Sánchez‐Llerena José Manuel Rato‐Nunes María Ángeles Rozas 《Pest management science》2017,73(6):1067-1075
Bentazon is a widely used herbicide in rice agroecosystems that has commonly been found in water resources. To assess how tillage and water regimes affect sorption/desorption, dissipation and leaching of bentazon in Mediterranean rice‐growing conditions, field experiments were carried out using tillage and flooding (TF), tillage and sprinkler irrigation (TS), no‐tillage and sprinkler irrigation (NTS) and long‐term no‐tillage and sprinkler irrigation (NTS7). After 3 years, the Kd values in TS were 2.3, 1.6 and 1.7 times lower than the values in NTS7, NTS and TF respectively. Greater sorption of bentazon was related to higher contents in total organic carbon and, although to a lesser extent, in humic acids and dissolved organic carbon. The persistence of bentazon was significantly greater under anaerobic (half‐life DT50 = 94.1–135 days) than under aerobic (DT50 = 42.4–91.3 days) incubation conditions for all management regimes. Leaching losses of bentazon were reduced from 78 and 74% in TS and TF to 61 and 62% in NTS7 and NTS respectively. The mid‐ and long‐term implementation of sprinkler irrigation in combination with no‐tillage could be considered a management system that is effective at reducing water contamination by bentazon in Mediterranean rice‐growing agroecosystems. © 2017 Society of Chemical Industry 相似文献
3.
Effect of Ovariohysterectomy at the Time of Tumor Removal in Dogs with Mammary Carcinomas: A Randomized Controlled Trial 下载免费PDF全文
4.
Profile of Steroid Receptors and Increased Aromatase Immunoexpression in Canine Inflammatory Mammary Cancer as a Potential Therapeutic Target 下载免费PDF全文
PJ De Andrés S Cáceres M Clemente MD Pérez‐Alenza JC Illera L Peña 《Reproduction in domestic animals》2016,51(2):269-275
Canine inflammatory mammary cancer (IMC) has been proposed as a model for the study of human inflammatory breast cancer (IBC). The aims of this study were to compare the immunohistochemical expression of aromatase (Arom) and several hormone receptors [estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR) and androgen receptor (AR)], in 21 IMC cases vs 19 non‐IMC; and to study the possible effect of letrozole on canine IMC and human inflammatory breast cancer (IBC) in vitro using IPC‐366 and SUM‐149 cell lines. Significant elevations of the means of Arom Total Score (TS), ERβ TS and PR TS were found in the IMC group (p = 0.025, p = 0.038 and p = 0.037, respectively). Secondary IMC tumours expressed higher levels of Arom than primary IMC (p = 0.029). Non‐IMC PR‐ tumours contained higher levels of Arom than non‐IMC PR+ tumours (p = 0.007). After the addition of letrozole, the number of IMC and IBC cells dropped drastically. The overexpression of Arom found and the results obtained in vitro further support canine IMC as a model for the study of IBC and future approaches to the treatment of dogs with mammary cancer, and especially IMC, using Arom inhibitors. 相似文献
5.
Anna Bassols José Angel Robles-Guirado Laura Arroyo Lourdes Soler Natalia García Raquel Pato Raquel Peña Yolanda Saco Ramon Armengol Fermín Lampreave María A. Alava Francesca Canalias Matilde Piñeiro 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(Z1):64-74
6.
Lydia Serrano Xavier Carbonell Robert Savé Oriol Marfà Josep Peñuelas 《Irrigation Science》1992,13(1):45-48
Summary Strawberry plants (Fragaria x annanasa D. cv Chandler) were grown in field plots and in drainage lysimeters under controlled soil moisture regimes. Four irrigation treatments were established by watering the plants when soil water potential reached -0.01, -0.03,-0.05 and -0.07 MPa. The maximum yield was attained at -0.01 MPa soil water potential. Differences in yield were caused by both changes in the number of fruits per plant and in the fresh weight per fruit. Yield reductions were associated with reductions in total assimilation rate resulting from the decreased assimilatory surface area in plants irrigated at lower soil water potentials. The crop water production function calculated on a fruit fresh weight basis resulted in a yield response factor (K
y) of 1.01. 相似文献
7.
Tania S. Peña James R. Watson Laura I. González-Guzmán Timothy H. Keitt 《Landscape Ecology》2017,32(8):1643-1656
Context
Many nearshore species are distributed in habitat patches connected only through larval dispersal. Genetic research has shown some spatial structure of such metapopulations and modeling studies have shed light onto possible patterns of connectivity and barriers. However, little is known about human impact on their spatial structure and patterns of connectivity.Objectives
We examine the effects of fishing on the spatial and temporal dynamics of metapopulations of sedentary marine species (red sea urchin and red abalone) interconnected by larval dispersal.Methods
We constructed a metapopulation model to simulate abalone and sea urchin metapopulations experiencing increasing levels of fishing mortality. We performed the modularity analysis on the yearly larval connectivity matrices produced by these simulations, and analyzed the changes of modularity and the formation of modules over time as indicators of spatial structure.Results
The analysis revealed a strong modular spatial structure for abalone and a weak spatial signature for sea urchin. In abalone, under exploitation, modularity takes step-wise drops on the path to extinction, and modules breakdown into smaller fragments followed by module and later metapopulation collapse. In contrast, sea urchin showed high modularity variation, indicating high- and low-mixing years, but an abrupt collapse of the metapopulation under strong exploitation.Conclusions
The results identify a disruption in larval connectivity and a pattern of collapse in highly modular nearshore metapopulations. These results highlight the ability of modularity to detect spatial structure in marine metapopulations, which varies among species, and to show early changes in the spatial structure of exploited metapopulations.8.
Robert Manuel L. Juárez-Gómez Juan Chaires-Pacheco Mariana Peña-Ramírez Yuri J. 《New Forests》2020,51(2):335-347
New Forests - Spanish red cedar, Cedrela odorata L. (Meliaceae), is a valuable timber tree in tropical American forests. Existing demand for elite individuals endangers the conservation of... 相似文献
9.
Santana Pedro Henrique Lopes Burak Diego Lang Thiengo Cássio Carlette Peçanha Anderson Lopes Neves Mirna Aparecida Mendonça Eduardo de Sá 《Journal of Soils and Sediments》2020,20(11):4103-4110
Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for... 相似文献
10.
冬播麦区Glu-1和Glu-3位点变异及1B/1R易位与小麦加工品质性状的关系 总被引:22,自引:3,他引:22
贮藏蛋白组成是决定小麦加工品质的重要因素。本文调查了我国冬播麦区251份主栽品种和高代品系的高分子量麦谷蛋白亚基(HMW-GS)、低分子量麦谷蛋白亚基(LMW-GS)和1B/1R易位的分布状况,研究了它们与加工品质性状的关系。结果表明,品质较差的HMW-GS N、7+9、2+12和LMW-GS Glu-A3a与Glu-B3j(1B/1R易位)在冬播麦区分布较广,频率分别为39.4%、45.0%、59.8%、37.1%和44.6%。HMW-GS和LMW-GS等位变异对籽粒蛋白质含量影响较小,对SDS沉降值、和面时间与耐揉性的加性和互作效应达1%的显著水平。按位点对加工品质性状的贡献大小,Glu-D1>Glu-B3>Glu-B1>Glu-A3>Glu-A1;就单个亚基而言,Glu-A1位点,1>2*>N;Glu-B1位点,7+8>14+15>7+9;Glu-D1位点,5+10>4+12>2+12;Glu-A3位点,Glu-A3d>Glu-A3a>Glu-A3c>Glu-A3e,Glu-B3位点; Glu-B3d>Glu-B3b>Glu-B3f >Glu-B3j。1B/1R易位对SDS沉降值、和面时间和耐揉性等加工品质性状有显著负面效应。通过选择优质高低分子量麦谷蛋白亚基和淘汰1B/1R易位系,将有助于提高我国小麦的面筋质量。 相似文献