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排序方式: 共有732条查询结果,搜索用时 15 毫秒
1.
A minialurized method of determining the toxicity of pesticides to large numbers or soil mitroorganisms is described. Bacteria. actinomycetes, yeasts, fungi and algae can be used as test organisms. A modification of the method allows determination of minimum inhibitory concentrations of pesticides to specific microorganisms. Some results obtained with herbicides are presented. Microméthodex pour éprauver la toxicité des pesticides vis-á-vis des micro-organismes Une micromethode pour determiner la toxicité des pesticides vis-á-vis de nombreux micro-organismes du sol est décrite. Des bactéries. des actinomycetes, des levures. des champignons et des algues peuvent ëtre utilisés comme organismes-tesis. Une modifitation de la méthode permel les determinations des concentrations minimales inhibitrices des pesticides vis-á-vis des micro-organismes specifiques. Quelques resultats obtenus avec des herbicides sont présentés. Miniaturisierte Methoden zur Prüf'ung der Toxizitüt von Pflan- zenhehandlumgsmit teln auf Mikraorganismen Es wird einc miniaturisierte Methode zur BestimmungderToxi- zität von Pfianzenbehandlungsmitteln für groβe Zablen von Bodenmikroorganismen beschrieben, Als Testorganismen können Bakterien. Actinomyceten. Hefen, Pilze und Algen benutzi werden. Eine Modifizierung der Methode gestattet die Bestimmung der Minimum-Hemmkonzentration von Pflanzen- behandlungsmitteln auf spezielle Mikroorganismen. Einige Ergebnisse, die mit Herbiziden erarbeitel wurden. sind darge-stellt. 相似文献
2.
F. Gentilini C. Calzolari A. Buonacucina M. Di Tommaso G. Militerno P. Famigli Bergamini 《Veterinary and comparative oncology》2005,3(2):87-97
Waldenström Macroglobulinemia is a low‐grade immunosecretory disorder associated with lymphoid tumours, which is rarely reported in veterinary medicine. In this study, we describe two clinical cases of this rare syndrome in dogs, each characterized by a different onset and clinical course. In one case, a hyperacute onset and aggressive behaviour of the neoplasm was observed. Absolute serum viscosity (SV) was retrospectively evaluated in order to explain clinical findings. Rotational viscosimetry showed good precision in measuring SV. Both dogs had SV values higher than a control groups of healthy dogs although only one subject developed hyperviscosity symptoms and complications. At high paraprotein concentrations, a slight reduction of the M‐component was associated with a marked decrease in SV. Thus, this work suggests that SV assessment is a relevant tool for managing monoclonal gammopathies, whose usefulness should be further confirmed in larger cohorts of dogs. 相似文献
3.
4.
Alessandra Bertoli Anthea LoBue Luca Quattrini Stefania Sartini Beatrice Polini Sara Carpi Francesco Paolo Frontini Graziano Di Giuseppe Graziano Guella Paola Nieri Concettina La Motta 《Marine drugs》2022,20(11)
Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound. 相似文献
5.
新侵入害虫蔗扁蛾的寄主范围正在扩大 总被引:8,自引:0,他引:8
蔗扁蛾Opogona sacchari (Bojer)是一种新传入我国的重要检疫害虫,给花卉生产、园林绿化和华南的经济作物生产造成严重威胁。该虫属鳞翅目Lepidoptera,辉蛾科Hieroxestidae,扁蛾属Opogona,广谱钻蛀性贪食者,已记载的寄主植物达22科49种,其中主要包括一些名贵观赏植物如巴西木[香龙血树Dracena fragrans(L.)]、发财树和经济作物如甘蔗、香蕉等。该虫在南美巴巴多斯为害甘蔗的程度超过蔗螟Diatraea saccharalis,在非洲加那利群岛对香蕉造成毁灭性为害。因此,许多国家将其列为重要的检疫对象。我国1997年正式报道在北京发现此虫,虫源是广州北运的巴西木。笔者在广州及其附近县市的初步调查表明,该虫除主要为害巴西木和发财树外,其寄主范围已扩大至 相似文献
6.
西藏降水化学分析 总被引:3,自引:0,他引:3
1987-1988年及1997-2000年间,在西藏拉萨、定日、当雄、安多采集降雨样品及部分大气浮尘样品,分析测定了pH、电导率、CO2分压、总悬浮颗粒含量及10多种离子浓度。共测量了300场次降雨的pH值、电导率和其中60场次降雨的化学成分含量。结果显示:青藏高原降雨常呈弱碱性,1987-1988年间加权平均pH值为8.36,1997-1999年间为7.5。造成高原降雨呈弱碱性的主要原因是来自地面富含钙的粉尘。西藏是世界上空气污染最轻的地方,但是从20世纪80-90年代的降雨中,NO3^-与SO4^2-含量增加,pH值降低,表明保护这片脆弱环境的紧迫性。 相似文献
7.
Rose Luiza Moraes Tavares Zigomar Menezes de Souza Diego Silva Siqueira Newton La Scala Júnior Alan Rodrigo Panosso 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):755-762
Sugarcane management systems affect soil attributes such as the carbon cycle. This fact has stimulated the sugar and alcohol industry to refine the sugarcane production systems by replacing the pre-harvest burning (PB) and manual harvest with mechanized harvesting followed by residue deposition. The aim of this study was to evaluate different management systems with respect to C cycling carbon dioxide and soil parameters (chemical, physical and biological) which were determined over the season. Three sugarcane cultivation systems were evaluated at the following periods: (a) PB, (b) 5-year green harvest and (c) 10-year green harvest. The results indicated that CO2 emission was 36% greater in the 10-year sugarcane green harvest system than in the PB system. The bulk density and macroporosity were the factors that were most affected by the different sugarcane management systems and that significantly influenced soil CO2 emissions. The principal component analysis showed that soil CO2 emission was 18% influenced by base saturation (V%) and 14% by pH, especially in the PB area. Additionally, 19% was affected by carbon and macroporosity in the 5- and 10-year green harvest areas, respectively. From our results, it can be concluded that the most CO2 emissions are in the areas of sugarcane green, this is due to the higher carbon concentration when compared with the area of burning sugarcane. The parameters that most influenced the CO2 emissions were bulk density, porosity, macroporosity, pH and V%. 相似文献
8.
Mariarita Romanucci Paolo E. Crisi Maria Veronica Giordano Morena Di Tommaso Francesco Simeoni Leonardo Della Salda 《Journal of veterinary diagnostic investigation》2021,33(1):112
A 14-y-old spayed female Labrador Retriever was presented with an 8-mo history of chronic vomiting. Abdominal ultrasound and gastrointestinal endoscopy revealed a mass protruding into the gastric lumen, with cytologic features suggestive of sarcoma. A partial gastrectomy was performed; the gastric body and antrum were thickened, with a cerebriform appearance of the mucosal surface. Histologic examination revealed a submucosal neoplastic proliferation of fusiform cells variably arranged in irregular bundles and scattered whorls. Fusiform cells strongly reacted to antibodies against vimentin, S100, and neuron-specific enolase; glial fibrillary acidic protein was moderately and multifocally expressed. Pancytokeratin, KIT, α–smooth muscle actin, and desmin were nonreactive. Histologic and immunohistochemical findings suggested a diagnosis of gastric sarcoma with features referable to a non-GIST (gastrointestinal stromal tumor), non–smooth muscle NIMT (non-angiogenic, non-lymphogenic intestinal mesenchymal tumor). The overlying gastric mucosa was thickened by elongated and dilated gastric glands, predominantly lined by intensely periodic acid-Schiff–stained mucous cells. This altered mucosal architecture was suggestive of Ménétrier-like disease. Although this disease has been hypothesized to predispose to gastric adenocarcinoma in dogs, an association with gastric sarcoma has not been documented previously in the veterinary literature, to our knowledge. 相似文献
9.
Tommaso Gregori Richard Lam Simon L. Priestnall Christopher R. Lamb 《Veterinary radiology & ultrasound》2016,57(6):582-586
The truncation artifact in magnetic resonance (MR) images is a line of abnormal signal intensity that occurs parallel to an interface between tissues of markedly different signal intensity. In order to demonstrate the truncation artifact in sagittal images of the canine spinal cord and the effect of changing spatial resolution, we conducted an experimental in vitro study. A section of fixed canine spinal cord was imaged using a 1.5T magnet. Spatial resolution was increased by increasing the acquisition matrix and reconstruction matrix, producing series of T2‐weighted (T2w) images with the following pixel sizes: A, 1.6 (vertical) × 2.2 mm2 (horizontal); B, 1.2 × 1.7 mm2; C, 0.8 × 1.1 mm2; D, 0.4 × 0. 6 mm2. Plots of mean pixel value across the cord showed variations in signal intensity compatible with truncation artifact, which appeared as a single, wide central hyperintense zone in low‐resolution images and as multiple narrower zones in high spatial resolution images. Even in images obtained using the highest spatial resolution available for the MR system, the edge of the spinal cord was not accurately defined and the central canal was not visible. The experiment was repeated using an unfixed spinal cord specimen with focal compression applied to mimic a pathologic lesion. Slight hyperintensity was observed within the spinal cord at the site of compression although the cord was normal histologically. Results of this study suggest that caution should be applied when interpreting hyperintensity affecting the spinal cord in T2w sagittal images of clinical patients because of the possibility that the abnormal signal could represent a truncation artifact. 相似文献
10.
La Bonnardière C Bonaiti B Abrial D Gasqui P Calavas D Ducrot C Barnouin J 《Preventive veterinary medicine》2007,78(1):67-78
The epidemic of bovine spongiform encephalopathy (BSE) in France, as in the UK, has affected dairy cattle much more than beef cattle. However, the intensification of dairy herd management as a risk factor for BSE has not to date been analyzed. For this purpose, two databases were merged: the French Milk Records database, and the French BSE database, which can be considered as being devoid of notification bias since July 2001, when systematic tests were implemented. Only pure Holstein herds were considered, which represent the vast majority of total and BSE-affected dairy herds in France. A case-control study was designed so that 20 control herds were matched to each case herd according to the location of the farm and the year of birth of the index case. Three thousand and forty five farms were included, among which 145 with a BSE case notified between July 2001 and July 2003, and 2900 controls. With respect to the risk of BSE, odds ratios for each class of milk yield and age at first calving were estimated by using conditional logistic regression models with appropriate adjustments to herd size. The two main results were the following: firstly, whereas most Holstein herds, with average production between 7000 and 10,000kg, had nearly the same BSE risk, a small category of very intensive herds, with annual milk yields above 10,000kg, were significantly more at risk than the other herds. Secondly, a very early first calving (under 26 months of age) was found to be at risk for BSE as compared to other categories, independently of the milk yield. These results are discussed in the light of the known age-dependent susceptibility to BSE. 相似文献