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91.
Braconi D Possenti S Laschi M Geminiani M Lusini P Bernardini G Santucci A 《Journal of agricultural and food chemistry》2008,56(10):3836-3845
Agricultural herbicides are among the most commonly used pesticides worldwide, posing serious concerns for both humans, exposed to these chemicals through many routes, and the environment. To clarify the effects of three herbicides as commercial formulations (namely, Pointer, Silglif, and Proper Energy), parameters related to oxidative issues were investigated on an autochthonous wine yeast strain. It was demonstrated that herbicides were able to affect the enzymatic activities of catalase and superoxide dismutase, as well as to induce carbonylation and thiol oxidation as post-translational modifications of proteins. Saccharomyces cerevisiae is an optimal model system to study responses to xenobiotics and oxidative stress. Thus, the results obtained could further the understanding of mechanisms underlying the toxicity of herbicides. 相似文献
92.
93.
Silvia M. Contreras-Ramos Dioselina Álvarez-Bernal Luc Dendooven 《Soil biology & biochemistry》2008,40(7):1954-1959
Earthworms burrow through the soil thereby accumulating many lipophilic organic pollutants from the surrounding environment, so they could be used to remove polycyclic aromatic hydrocarbons (PAHs) from soil. Sterilized and unsterilized soil was contaminated with phenanthrene (Phen), anthracene (Anth) and benzo[a]pyrene (BaP), with or without added Eisenia fetida and biosolid or vermicompost. Concentrations of PAHs were monitored in soil and earthworms for 70 days. Removal of PAHs increased in soil with earthworms added as 91% of Anth, 16% BaP and 99% Phen was dissipated compared to 42%, 3% and 95% in unamended soil. The microorganisms in the gut of the earthworm contributed to PAHs removal and 100% of Phen, 63% of Anth and 58% of BaP was removed from sterilized soil with E. fetida added. Biosolid and to lesser extent vermicompost accelerated removal of PAHs from soil. Applying earthworms to a contaminated site might be an environmentally friendly way to remove hydrocarbons from soil. However, a limitation might be the cost of the large amounts of earthworms required to remove PAHs from soil and the necessity to supply them with sufficient substrate while maintaining the water content of the soil high enough for their normal functioning. 相似文献
94.
Farroni AE Matiacevich SB Guerrero S Alzamora S Del Pilar Buera M 《Journal of agricultural and food chemistry》2008,56(15):6447-6453
The purpose of this work was to analyze the effect of water on thermal transitions, mechanical properties, and molecular mobility in corn flakes (CF), and their relationships. Commercial common (CCF) and sugar-frosted (SCF) corn flakes were studied in a water content (wc) range from 5 to 20 (% dry basis). The slope of (1)H NMR spin-spin relaxation time T 2* (determined by FID) versus temperature plot changed close to T g. Compression force showed a maximum at wc of ca. 12 and 16% (db) for SCF and CCF, respectively. (1)H NMR complemented DSC data in determining the temperature dependence of water and solid mobility, in order to assess quality of laminated corn products. The results of the present work indicate that while the compression force showed a maximum value as a function of water content, T g values determined by DSC or by spin-spin relaxation decreased progressively with increasing water content. 相似文献
95.
Justice A. Tambo Roger K. Day Julien Lamontagne-Godwin Silvia Silvestri Patrick K. Beseh Birgitta Oppong-Mensah 《国际虫害防治杂志》2020,66(4):298-310
AbstractSince its emergence in Africa in 2016, fall armyworm (FAW) has spread rapidly and poses a severe threat to the food security and livelihood of millions of smallholder farmers in the continent. Using survey data from Ghana and Zambia, we examined FAW prevention and control methods implemented by farm households and their impacts on maize output and household consumption of self-produced maize. The main control methods used included pesticide application and handpicking of larvae, while access to information on FAW was a key driver behind the implementation of the control methods. Results from an endogenous switching regression showed that the implementation of a FAW management strategy significantly enhanced maize yield and households’ own maize consumption. When disentangling the impacts of the main control methods, we found that the combination of pesticide application and handpicking of larvae produced the highest yield gain of 125%. We concluded that the current interventions put in place by farmers to tackle FAW infestations are providing positive outcomes, but successful management of the pest will require more actions, including raising awareness to enhance the adoption of control interventions and exploring other control options. 相似文献
96.
97.
Mast cells (MCs) are well known for their neoplastic transformation in solitary and multiple cutaneous mast cell tumours (MCTs), as well as visceral and systemic mastocytosis. Dogs have a unique risk of developing cutaneous MCTs, and they account for 7% to 21% of all canine skin tumours. The aetiology of canine MCTs is unknown but is probably multifactorial. This article reviews up-to-date knowledge on the pathogenesis, the clinical presentation, the clinical prognostic factors, the diagnostic workup including clinical staging, cytological findings, histological findings and the various grading systems which have been evaluated based on morphology, the assessment of proliferation markers and other factors such as vessel density. Furthermore, detailed information about current treatment protocols for canine cutaneous MCTs is provided. 相似文献
98.
Zanetti S Bua A Molicotti P Delogu G Mura A Ortu S Sechi LA 《Acta veterinaria Hungarica》2008,56(2):145-152
During a six-month period a region of Northern Sardinia was monitored to check the presence of mycobacterial infections in wild boars. Forty-eight serum and 229 biopsy samples were collected from different animals and examined by both traditional diagnostic techniques (culture, bacterioscopic and molecular tests) and enzyme-linked immunosorbent assay (ELISA). The latter was used to determine the antibody response against both methylated and nonmethylated Heparin-Binding Haemagglutinin (HBHA) protein. Nine mycobacterial strains were isolated: three M. avium ssp. paratuberculosis (Map), three M. avium, one M. interjectum and two M. scrofulaceum strains. By PCR, only one animal was positive for M. bovis, whereas 10 animals were positive for Map. Out of the 48 sera tested, 19 showed a good humoral response to methylated HBHA and 17 to nonmethylated HBHA. Our data provide new information on the prevalence of mycobacterial infection among wild boars in Northern Sardinia and suggest that a more effective program should be developed to monitor mycobacterial infections in the wild animal population. 相似文献
99.
Laura Marconato Carmit Chalfon Riccardo Finotello Gerry Polton Maria E. Vasconi Maurizio Annoni Damiano Stefanello Paola Mesto Ombretta Capitani Chiara Agnoli Maria Amati Silvia Sabattini 《Veterinary and comparative oncology》2019,17(4):537-544
Treatment options for dogs with metastatic (stage III) splenic hemangiosarcoma are limited. A doxorubicin‐based chemotherapy regimen is commonly administered; however, there are no published data to support this practice. The aim of this study was to investigate the impact of maximum‐tolerated‐dose chemotherapy (MTD), metronomic chemotherapy (MC) and no adjuvant treatment on outcome in dogs with stage III splenic hemangiosarcoma undergoing splenectomy. Medical records of dogs with stage III splenic hemangiosarcoma that underwent splenectomy followed by MTD chemotherapy, MC or no adjuvant treatment were retrieved. Time to progression (TTP), survival time (ST) and toxicity were evaluated. One hundred three dogs were identified: 23 received adjuvant MTD, 38 MC and 42 were not medically treated. Overall median TTP and ST were 50 (95% confidence interval [CI], 39‐61) and 55 days (95% CI, 43‐66), respectively. Dogs treated with adjuvant MTD had a significantly longer TTP and ST compared with dogs receiving MC (median TTP, 134 vs 52 days, P = .025; median ST, 140 vs 58 days, P = .023, respectively). Dogs treated by splenectomy only had the shortest median TTP (28 days) and ST (40 days). However, treatment‐related adverse events (AEs) were significantly more frequent in the MTD group (P = .017). The outcome for dogs with metastatic splenic hemangiosarcoma is poor. While MTD showed greater efficacy compared to MC, toxicity was higher in this group. Treatment‐related AEs need to be carefully balanced against this modest survival prolongation when offering adjuvant MTD to dogs with advanced stage hemangiosarcoma. 相似文献
100.
Silvia Kohutova Michaela Paninarova Miša Škorič Vladimir Jekl Zdenek Knotek Karel Hauptman 《Journal of Exotic Pet Medicine》2018,27(1):41-45
A 3-year-old, 920 g intact female guinea pig presented with a 4-month history of nonpruritic hair loss on the ventral abdomen. The physical examination revealed flank and ventral abdominal alopecia, mucoid vulvar discharge, and abdominal distension. Bilateral rounded masses just caudal to the kidneys and structures consistent with enlarged uterine horns were detected on abdominal palpation. Abdominal ultrasound revealed bilateral ovarian cysts, thickened uterine horns, and multiple circular hypoechoic and anechoic structures in the uterine wall. The patient underwent ovariohysterectomy. Gross examination of the uterus revealed a piece of hay in the left uterine horn. A final diagnosis was hormonally active ovarian follicular cysts, cystic endometrial hyperplasia, and purulent bacterial endometritis caused by Escherichia coli, Fusobacterium nucleatum, and Arthrobacter spp. Cystic endometrial hyperplasia is infrequently reported in guinea pigs, and this report describes an associated bacterial endometritis and uterine foreign body with concurrent ovarian cysts. 相似文献