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排序方式: 共有350条查询结果,搜索用时 390 毫秒
31.
Cabizza M Angioni A Melis M Cabras M Tuberoso CV Cabras P 《Journal of agricultural and food chemistry》2004,52(2):288-293
Rotenone and rotenoids (deguelin, beta-rotenolone (12a beta-hydroxyrotenone), tephrosin (12a beta-hydroxydeguelin), 12a alpha-hydroxyrotenone, and dehydrorotenone) were determined in cubè resins and formulations. Cubè resins from Lonchocarpus contain large quantities of deguelin (ca. 21.2%) and smaller quantities of tephrosin (ca. 3.5%) and beta-rotenolone (ca. 3.0%). The composition of commercial formulations may present very different rotenoid contents depending on the extracts used to prepare them. Because these rotenoids also present insecticide activity, the efficacy of these formulations may be very different. The storage stability and photodegradation of some rotenone formulations were studied. Rotenone and rotenoids are very sensitive to solar radiation, which degrades them rapidly, with half-lives in the order of a few tens of minutes. Some formulations show greater disappearance rates than that of cubè resin, indicating that not much attention has been paid to protecting the active ingredients from photodegradation in the formulation. A study on the residues on olives was also carried out to assess not only the rotenone content, but also that of the main rotenoids. At harvest, the residues of deguelin, tephrosin, and beta-rotenolone were 0.10, 0.06, and 0.10 mg/kg, respectively, very similar to rotenone (0.08 mg/kg), and though a few data indicate similar acute toxicity values for deguelin, only rotenone is taken into consideration in the legal determination of the residue. 相似文献
32.
Mario Cipone DVM Marco Pietra DVM Gulatiero Gandini DVM Andrea Borai DVM Carlo Guglielmini DVM Massimiliano Venturoli DVM 《Veterinary radiology & ultrasound》1997,38(3):200-206
A pulsed wave-Doppler ultrasonographic evaluation of common carotid arterial blood flow was carried out on 63 healthy Italian Saddlebred horses. Vessel diameter and tracing morphology were evaluated were evaluated and blood flow parameters (systolic, diastolic and mean velocity, acceleration and deceleration of the systolic wave, cartid pulse volume) were calculated and correlated with class variables (sex, age and body weight). On the basis of the presence of an incisure in the ascending branch of the systolic curve, subjects were divided in two groups: one with a bifid systolic curve and the other with a monophasic aspect. Correlations between: 1) diameter of the vessel and body weight and 2) carotid pulse volume and flow velocity (systolic, diastolic and mean) were found. A greater systolic pulse volume was found in male subjects, in subjects with greater body weight and in those which had a monophasic systolic wave. 相似文献
33.
De Lorenzi D Bonfanti U Masserdotti C Tranquillo M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(2):100-105
BACKGROUND: The cytologic diagnosis of ear canal tumors is difficult or impossible by swab alone because cell exfoliation may be poor and neoplastic cells may be masked by associated inflammation. Fine-needle biopsy (FNB) can be used to obtain a higher yield of cells for diagnosis. OBJECTIVE: The purpose of this study was to assess the efficacy and diagnostic value of FNB and cytologic examination in providing an accurate diagnosis of masses growing in the external ear canal of cats. METHODS: Cytologic specimens from masses in the external ear canal, taken under inhaled, general anesthesia, were classified into 4 groups: 1) ceruminous gland hyperplasia or adenoma, 2) ceruminous gland adenocarcinoma, 3) inflammatory polyps, and 4) other neoplastic and non-neoplastic masses. Cytopathologic diagnoses were compared with the final histopathologic diagnoses, and indices of diagnostic test accuracy (sensitivity, specificity, likelihood ratios, diagnostic-odds ratios) were calculated. RESULTS: Twenty-seven masses (from 25 cats, including 2 cats affected bilaterally) were included in the study. The results showed good correspondence between cytologic and histologic diagnoses with an overall agreement index (kappa) of .74, a diagnostic odds ratio of 22, and 100% (27/27) agreement in the diagnosis of inflammatory polyps versus neoplasia (both benign and malignant). CONCLUSIONS: FNB cytopathology of external ear masses in the cat was sufficiently accurate for distinguishing inflammatory polyps from neoplasia. For differentiation of benign proliferation and malignant neoplasia, however, histopathologic confirmation is recommended. 相似文献
34.
Dacasto M Eeckhoutte C Capolongoa F Dupuy J Carletti M Calléja C Nebbia C Alvinerie M Galtier P 《Veterinary research》2005,36(2):179-190
The cytochrome P450 (P450) superfamily represents a group of relevant enzymes in the field of drug metabolism and several exogenous or constitutional factors contribute to regulate its expression. Cattle represent an important source of animal-derived food-products and studies concerning the P450 expression are needed for the extrapolation of pharmacotoxicological data from one species to another and for the evaluation of the consumer's risk associated with the consumption of harmful residues found in foodstuffs. In the present study, possible breed-, gender- and species-differences in P4503A (the P450 subfamily more expressed in the human liver) expression were studied in vitro in Piedmontese (PDM) and Limousin (LIM) meat cattle breeds of both sexes and in domestic Ruminants (cattle, sheep and goats). Cytochrome P450 and P4503A contents as well as CYP3A-dependent drug metabolising enzymes (DME) were measured in liver microsomes. Significant lower levels of P450 (P < 0.001) and P4503A (P < 0.05) contents were observed in PDM vs. LIM of both sexes; the P4503A-dependent DME activities were significantly (P values ranging from 0.05 up to 0.001) higher in PDM cattle, particularly in males. A gender-effect in DME activities was noticed (P < 0.05) only in PDM male cattle. With regards to the species, the expression of both P4503A apoprotein and some of the related DME activities were more pronounced in sheep (P < 0.01 vs. cattle) and in goats (P < 0.05 vs. sheep; P < 0.01 vs. cattle) than in cattle. The significant differences in P4503A expression observed in LIM and PDM cattle are consistent with previously published data on strain- and breed-differences pointed out in rats and men. As far as a possible sex-effect is concerned, no clear-cut evidence is likely to be drawn. Finally, P4503A expression was more relevant in small ruminants. 相似文献
35.
Guido?MarchiEmail author Carlo?Viti Luciana?Giovannetti Giuseppe?Surico 《European journal of plant pathology / European Foundation for Plant Pathology》2005,112(2):101-112
Mixtures of wet vegetable wastes (Brassica, carrot or onion) and dry onion waste were composted at 50 °C for 7 days. The incorporation of the raw or composted vegetable waste mixtures into sandy loam, silt and peat soils reduced the viability of sclerotia of S. cepivorum in glasshouse pot bioassays. The reduction in viability was dependent on waste type, rate of incorporation, duration of exposure and soil type. Onion waste was the most effective waste type in reducing sclerotia viability in all three soils. The Brassica and carrot wastes were as effective as the onion waste in silt soil but less effective in sandy loam and peat soil. A 50% w/w incorporation rate of the wastes gave the largest reduction in viability, with an increase in reduction over time. Composted onion waste reduced sclerotia viability under glasshouse and field conditions although the effect was smaller in the field. Composted onion waste incorporated into soil at 50% w/w reduced the incidence of Allium white rot on onion seedlings in glasshouse pot tests. Incidence and control of the disease differed with soil type. The most consistent control was achieved in peat soil whereas no control was observed in silt soil. Incorporation of the waste 2 months prior to sowing or transplanting reduced seedling emergence in sandy loam soil and growth in all three soil types. The potential for field application of composted vegetable wastes as a sustainable method for control of Allium white rot and waste disposal is discussed. 相似文献
36.
37.
Diana A Preziosi R Guglielmini C Degliesposti P Pietra M Cipone M 《American journal of veterinary research》2004,65(12):1625-1630
OBJECTIVE: To assess the applicability of high-frequency diagnostic ultrasonography for evaluation and accurate measurement of the skin thickness of clinically normal dogs. ANIMALS: 26 healthy dogs (12 sexually intact males, 13 sexually intact females, and 1 spayed female) of various breeds and ages. PROCEDURE: Ultrasonographic examination of the skin and histomorphometric analysis of skin biopsy specimens obtained from the same site were performed. A 13-MHz linear-array transducer was used to obtain a series of ultrasonographic images of the skin in the flank region; images were analyzed and measured by use of imaging software. Cutaneous biopsy specimens were placed in fixative and then stained with H&E and Masson trichrome stains. Histomorphometric analysis was performed by use of an image analyzer. Thickness of the epidermis and dermis of each specimen was evaluated by use of a semiautomatic procedure of quantification. Data obtained from ultrasonographic and histologic measurements were compared by use of the Pearson correlation test. RESULTS: The ultrasonographic pattern of canine skin was consistently characterized by 3 distinct, defined echogenic layers corresponding to the epidermal entry echo, epidermis and dermis, and subcutaneous tissues. A positive correlation was found between ultrasonographic and histologic measurements of skin thickness. CONCLUSIONS AND CLINICAL RELEVANCE: Comparison between ultrasonographic and histologic appearance of the skin revealed that layering of canine skin (ie, epidermis and dermis) and the subcutaneous tissues may be recognized and measured by use of high-frequency ultrasonography. Thus, diagnostic ultrasonography may be a useful tool for the noninvasive evaluation of cutaneous disorders in dogs. 相似文献
38.
De Carlo E Re GN Letteriello R Del Vecchio V Giordanelli MP Magnino S Fabbi M Bazzocchi C Bandi C Galiero G 《The Veterinary record》2004,154(6):171-174
Two healthy buffaloes (Bubalus bubalis) in a herd which had not been vaccinated against infectious bovine rhinotracheitis (IBR), were selected for their seropositivity for anti-bovine herpesvirus type 1 (BoHV-1) glycoprotein E antibodies, and injected intramuscularly daily with dexamethasone for five consecutive days (day 1 to day 5) to reactivate any latent herpesvirus. Blood samples and nasal and vaginal swabs were collected daily from day 5 to day 15 from each buffalo for virological examination. All the vaginal swabs and blood samples were negative, but 13 of the 22 nasal swabs were positive; a cytopathic effect was observed in primary cultures of bovine fetal lung cells, and the viral isolates were identified as a herpesvirus by PCR. The viral strains were characterised by the sequence analysis of the genes coding for glycoproteins D and B, and the gene sequences were then used for phylogenetic analysis. The isolates from both buffaloes appeared identical at the level of the two genes, and were more closely related to bovine herpesvirus type 5 than to BoHV-1. 相似文献
39.
Four different polyphenolic compounds were isolated by chromatographic methods from methanolic and hydromethanolic extracts of Ipomoea batatas tuber flour. On the basis of UV, mass, and NMR analysis procedures, the structure of the isolated compounds were determined as 4,5-di-O-caffeoyldaucic acid (1), 4-O-caffeoylquinic acid (2), 3,5-di-O-caffeoylquinic acid (3), and 1,3-di-O-caffeoylquinic acid (4). To the best of our knowledge, this is the first report of isolation and characterization of compound 1. Then, we evaluated the antioxidant activity of daucic acid derivative by using DPPH and FRAP methods together with authentic antioxidant standards, l-ascorbic acid, tert-butyl-4-hydroxy toluene (BHT), and gallic acid. The activity of compound 1 in both methods was higher than that of all standards used at the same molar concentration. 相似文献
40.