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31.
为了探索依据水面蒸发量确定灌溉定额的可行性,在防雨棚下测坑中进行了夏玉米灌溉试验。结果表明,从总耗水量看,畦灌略高于沟灌,而沟灌又略高于滴灌,但差别不是很大。畦灌条件下植株发育快,滴灌次之,沟灌最慢。畦灌和滴灌下产量均以中等灌溉定额处理最高,而沟灌下产量以最大灌溉定额处理最高。总体上,滴灌条件下水分利用效率高于其他2种灌溉方式。干旱条件下,畦灌下以E601蒸发皿蒸发量(PE)作为夏玉米灌溉定额,每次灌水60mm;滴灌下以2/3PE作为灌溉定额为宜,灌水定额为20mm。 相似文献
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Letter to the Editor re Hergt et al “Use of a 2‐tier histologic grading system for canine cutaneous mast cell tumors on cytology specimens”
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Mellor PJ Haugland S Murphy S Smith KC Holloway A Archer J Powell RM Polton GA Tasker S McCormick D Tempest ME McNeil PE Scase TJ Knott CD Bonfanti U Villiers EJ Argyle DJ Herrtage ME Day MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(6):1376-1383
BACKGROUND: Myeloma-related disorders (MRD) are rare neoplasms of plasma cells. Published case reports describe a diversity of clinical presentations with confusing terminology and diagnostic criteria as a consequence of the assumption that MRD in cats are analogous to those in dogs or humans. OBJECTIVE: The aim of the study was to describe clinical, clinicopathologic and imaging findings, response to treatment, survival and possible associations with other diseases or vaccination in a large case series. A priori hypotheses were that cats with MRD commonly present with extramedullary involvement and uncommonly have radiographic bone lesions, in contrast to human patients. ANIMALS: Twenty-four cats with MRD confirmed by cytology or histopathology and immunohistochemistry. METHOD: A multicenter retrospective study was performed. RESULTS: Two types of clinical presentation were observed. The first group (n = 17) had neoplasia involving abdominal organs, bone marrow, or both. All developed systemic clinical signs and paraproteinemia. Five of 7 cats that received chemotherapy improved clinically or had decreased serum globulin concentration (median survival, 12.3 months; range, 8.5-22 months). The second group comprised 7 cats with skin masses, 2 of which were paraproteinemic and developed rapidly worsening systemic signs. In cats without systemic signs, excision of the skin masses appeared to be associated with prolonged survival (up to 2.4 years). Cats with MRD commonly presented with extramedullary involvement (67%), versus humans with MRD (5%) (P < .001), and uncommonly presented with radiographic bone lesions (8%) versus humans with MRD (80%) (P < .001). CONCLUSIONS: Radiographic bone lesions are uncommon in cats with MRD and extramedullary presentation is common, relative to human myeloma. 相似文献
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Rogers I Emmett P Gunnell D Dunger D Holly J;ALSPAC Study Tteam 《Public health nutrition》2006,9(3):359-368
OBJECTIVE: The mechanisms underlying the association of insulin-like growth factor-I (IGF-I) and leg length (a marker of prepubertal growth) with cancer risk are uncertain. One hypothesis is that diet in early childhood might provide the link. The aim of the present study was to examine the association between early diet - in particular, the intakes of cows' milk and dairy products - and height, leg length and IGF-I levels at age 7-8 years.SUBJECTS: Children participating in the Avon Longitudinal Study of Parents and Children.DESIGN: Diet was assessed using a 3-day unweighed food record. Anthropometry, IGF-I and insulin-like growth factor-binding protein-3 (IGFBP-3) were measured by standard methods.RESULTS: Data on both diet and height were available for 744 children (404 boys) and on diet and IGF for 538 (295 boys). After adjusting for energy, both cows' milk and dairy product intakes were positively associated with IGF-I (P=0.040 and 0.027, respectively) and IGFBP-3 levels (P=0.082 and 0.067, respectively). These associations persisted on adjustment for potential confounders, but were abolished on controlling for protein intake. In energy-adjusted models there was only weak evidence of associations of milk and dairy product intakes with anthropometry. In boys only, dairy product intake was positively associated with leg length (equivalent to a 0.058 (0.002, 0.114) standard deviation score increase in leg length per 100 g increase in daily intake).CONCLUSIONS: These data provide some evidence that variation in childhood milk and dairy product intakes underlies associations of leg length, IGF-I and cancer risk. The association appears to be due to the protein content of milk. 相似文献
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Residues of iprodione and vinclozolin were measured following repeated application of the fungicides to a sandy loam soil in the laboratory. There was a progressive increase in rates of degradation with successive treatments. With iprodione, for example, the times for 50% loss of the first and second applications were about 23 and 5 days respectively. When treated for the third time, less than 10% of the applied dose remained in the soil after just 2 days. Similar results were obtained with vinclozolin in the same soil, and with both compounds in a second soil. In a third soil, which had relatively low pH, degradation of both compounds occurred only slowly and the rate of degradation of a second application was the same as that of the first. Degradation rates in this soil were increased by addition of 100 g kg?1 of a soil in which degradation occurred more readily, and they were markedly increased by addition of 100 g kg?1 of a soil in which enhanced degradation had been previously induced. Residues of both fungicides were also measured following repeated application in the field. When iprodione was applied to previously untreated plots, about 3% of the initial dose remained in the soil after 77 days. When applied to plots treated once before, less than 1% remained after 18 days, and when applied to plots treated twice previously less than 1% remained after 10 days. Similar results were obtained with vinclozolin. Enhanced degradation of subsequent soil treatments was also observed following a sequence of low-dosage sprays in the field. 相似文献
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Latimer KS Niagro FD Rakich PM Campagnoli RP Ritchie BW McGee ED 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1997,26(4):158-163
Cloacal and oral papillomas from 27 psittacine birds of various species were examined for the presence of parrot papillomavirus by DNA in situ hybridization, DNA in situ polymerase chain reaction, and nested polymerase chain reaction. Parrot papillomavirus was detected in one oral papilloma from an African grey parrot by all three techniques. In addition, rare basophilic intranuclear inclusions were observed by light microscopy in tissue sections of the oral papilloma from this parrot. The remaining lesions were negative for parrot papillomavirus DNA. This study suggests that parrot papillomavirus may be involved in the development of papillomas in African grey parrots, but apparently is not responsible for development of similar lesions in unrelated species of psittacine birds. 相似文献
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Evidence of farm-level synergies in mixed-farming systems in the Australian Wheat-Sheep Zone 总被引:1,自引:0,他引:1
Synergies are reported for mixed-enterprise farming systems in a benchmarking group in the Wheat-Sheep Zone in New South Wales, Australia. A stochastic input distance function is estimated and a measure of synergies is calculated, based on the second cross partial derivative of output variables in the distance function. Evidence is presented of strong synergies from complementarity between sheep and beef enterprises, sheep and crop enterprises, and beef and crop enterprises. 相似文献