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241.
242.
Lupin protein is capable of reducing plasma lipids in hypercholesterolemic man and animals. Whether lipid-lowering properties of lupin protein will be influenced by thermal treatment or by other nutrients has not been elucidated. In a two-factorial study, rats were fed hypercholesterolemic diets based on high amounts of carbohydrates (HC) or fat (HF), which contained either (20.4% of energy) untreated or thermally treated lupin protein (steam: 120 °C, 30 min) or casein as control protein. Lupin protein lowered plasma lipid concentrations in rats fed the HF diet but not in those fed the HC diet (P < 0.05). Among rats fed the HF diet, plasma and VLDL triglyceride concentrations were lower in rats fed thermally treated (−46% and −44%, P < 0.05) and untreated lupin protein (−47% and −46%, P < 0.05) than in those fed casein; whereas liver triglycerides were reduced only in rats fed untreated lupin protein (P < 0.05). Compared to casein, untreated lupin protein had slightly stronger cholesterol-lowering effects in plasma, LDL and HDL (−34%, −37%, −35%; P < 0.05) than thermally treated lupin protein (−23%, −29%, −31%, P < 0.10). In conclusion, the lipid-lowering effect of lupin protein strongly depends on composition of the basal diet, and thermal treatment is accompanied by a slight reduction of its hypocholesterolemic properties.  相似文献   
243.
Plasmopara viticola is an economically important pathogen of grapevine. Early detection of P. viticola infection can lead to improved fungicide treatment. Our study aimed to determine whether chlorophyll fluorescence (Chl-F) imaging can be used to reveal early stages of P. viticola infection under conditions similar to those occurring in commercial vineyards. Maximum (FV/FM) and effective quantum yield of photosystem II (ΦPSII) were identified as the most sensitive reporters of the infection. Heterogeneous distribution of FV/FM and ΦPSII in artificially inoculated leaves was associated with the presence of the developing mycelium 3 days before the occurrence of visible symptoms and 5 days before the release of spores. Significant changes of FV/FM and ΦPSII were spatially coincident with localised spots of inoculation across the leaf lamina. Reduction of FV/FM was restricted to the leaf area that later yielded sporulation, while the area with significantly lower ΦPSII was larger and probably reflected the leaf parts in which photosynthesis was impaired. Our results indicate that Chl-F can be used for the early detection of P. viticola infection. Because P. viticola does not expand systemically in the host tissues and the effects of infection are localised, Chl-F imaging at high resolution is necessary to reveal the disease in the field.  相似文献   
244.
A soil's cation exchange capacity (CEC) is expected to be relatively inert against changes in cation loading. In this study, we treated a soil sample originating from the organic layer of a forest soil with various bivalent cations after removing the native cations. Sorption isotherms and cation exchange capacity were determined, the latter using the BaCl2 method. Sorption showed Langmuir characteristics, with the maximum coverage (Qmax) increasing in the order Ba2+ < Ca2+ < Mg2+, but being clearly smaller than the initial load of native exchangeable cations. The Langmuir coefficient, kMe, depended oppositely to the order obtained for Qmax. CEC increased upon cation treatment and it varied by a factor of almost two. The unexpected variation of CEC was explained by the low cation exchange capacity of the organic matter such that not all functional groups are close enough to be bridged and the second charge of a bivalent cation is not neutralized by the organic functional group. The Langmuir sorption type, and Qmax being smaller than the content of sorption sites and being largest for Mg, suggested that only a part of the sites can be cross‐linked and at least part of the cross‐links are formed by hydrated cations. Thermodynamic considerations allowed reconstruction of two contrasting processes during CEC determination by Ba2+: Case A: the disruption of cross‐links, which increases with the cationic strength and the cation load before CEC determination, but does not require structural re‐orientation in the SOM matrix, and Case B: the formation of new cross‐links during CEC determination, depending only on the content of unoccupied sites before CEC determination and requiring structural re‐organization of the matrix and thus a minimum matrix flexibility. The use of bivalent cations for CEC determination may thus result in an overestimation of CEC for organic matter with low CEC. This has, however, promising potential when comparing CEC determined with monovalent cations and bivalent cations. Using a set of bivalent cations, may allow probing distribution of distances between functional groups in the organic matter and even characterize the matrix rigidity of the cation‐cross‐linked network.  相似文献   
245.
We have recently shown that inactivated parapoxvirus ovis (iPPVO) effectively stimulates canine blood phagocytes. However, a potential link between innate and adaptive immunity induced by iPPVO remained open. The objective of this study was to define the effects of repeated iPPVO treatment of dogs to evaluate (i) iPPVO-specific antibody production, and (ii) modulation of iPPVO-induced oxidative burst by anti-iPPVO antibodies. Serum analysis of dogs treated repeatedly with iPPVO (Zylexis®) showed transient production of non-neutralising iPPVO-specific IgG. There was a correlation between iPPVO-specific IgG levels and enhanced oxidative burst rates in vitro upon transfer of immune sera. Even four years after Zylexis® treatment considerably stronger oxidative burst rates in response to iPPVO were observed in monocytes and PMN, whereas only moderate burst rates were detected in monocytes, but not in PMN, from dogs treated with a placebo. Depletion of serum IgG by protein A-sepharose or by parapoxvirus ovis coupled to sepharose abolished the increase of oxidative burst responses and resulted in burst rates similar to blood leukocytes from control dogs. However, uptake of viral particles was found to be independent of iPPVO-specific IgG and restricted to cells with dendritic and monocytic morphology. These data demonstrate that non-neutralising iPPVO-specific IgG is produced during treatment with Zylexis®. Moreover, for the first time the interaction of iPPVO with antibodies is shown to enhance oxidative burst.  相似文献   
246.
We conducted a cross-sectional convenience sampling study of dogs racing in the 2010 Iditarod to determine the seroprevalence of canine influenza virus (CIV) in the sled dog population. Questionnaires were completed detailing medical and CIV vaccination history, kennel size and location, travel history, and social interactions for each team. A total of 399 dogs were tested for CIV antibodies by hemagglutination inhibition assay. None of these, including 39 samples from dogs reported as CIV vaccinated, were seropositive for CIV antibodies. All of the vaccinated dogs were also negative on virus microneutralization assay. Risk factors for CIV seropositivity could not be determined due to a lack of positive samples. This is the first published study investigating the prevalence of CIV in sled dogs and additional studies are warranted to assess CIV infection among racing sled dogs and to evaluate the ecology of CIV and the vaccine efficacy in this population of dogs.  相似文献   
247.
248.
Following pretreatment with clindamycin, cleaning, scaling, polishing, and curettage, six beagles that were patients at the Dental Department of the Clinic for Surgery and Ophthalmology of the University of Veterinary Medicine of Vienna received a doxycycline polymer filling (Doxirobe, Pharmacia Animal Health) in periodontal pockets of teeth 204, 208, 304, and 309. Gingivitis index, gingival crevicular fluid, probing depth, and attachment loss were determined before and 6 and 12 weeks after treatment. Teeth 104, 108, 404, and 409 did not receive antibiotic therapy but were pretreated in the same manner as the doxycycline-treated teeth. Pocket depth for teeth treated with doxycycline was significantly reduced (improved) by 39% after 6 weeks (P =.001) and by 35% after 12 weeks (P =.001). Pockets around control teeth were improved after cleaning and curettage but were still significantly deeper than around teeth treated with doxycycline. Compared with control teeth, teeth treated with doxycycline had significantly less gingival crevicular fluid after treatment (P =.001). Teeth treated with doxycycline gained significant attachment after 6 (42%) and 12 (38%) weeks. Significantly fewer bacteria were harvested from doxycycline-treated teeth than from control teeth. The gingival index was significantly lower in the doxycycline-treated teeth than in the control teeth 6 (P =.002) and 12 (P =.007) weeks after treatment. Local application of doxycycline complements traditional subgingival curettage therapy in a reasonable and effective way and can significantly improve treatment success, especially with regard to pocket depth reduction and attachment gain.  相似文献   
249.
An 8-year-old neutered male Boxer was presented with tenesmus, hemorrhagic urethral discharge, and dysuria. Abdominal ultrasound and radiographic examinations revealed irregular prostatic enlargement. Laparotomy was performed and intraoperative cytology was done on imprint smears of a biopsy specimen obtained from a prostatic mass. The cytologic preparation was highly cellular and contained a predominant population of atypical, large, loosely cohesive spindle cells, with rare multinucleated cells and mitotic figures. The cytologic findings were consistent with undifferentiated sarcoma. At necropsy, a large cystic prostatic mass and numerous satellite nodules in the soft tissues around the pelvis were found. On histologic examination the tumor was composed primarily of bundles of neoplastic spindle cells. Rare pseudo-acinar structures and signet-ring cells also were observed. On immunohistochemical examination, the neoplastic cells co-expressed cytokeratin and vimentin. Based on histologic and immunohistochemical findings, the tumor was diagnosed as primary prostatic sarcomatoid carcinoma. This is a rare tumor in dogs, in which biphasic morphology of epithelial and mesenchymal cells can complicate the diagnosis, requiring immunochemical stains for confirmation.  相似文献   
250.

Given its high nutritional value and capacity to grow in harsh environments, quinoa has significant potential to address a range of food security concerns. Monitoring the development of phenotypic traits during field trials can provide insights into the varieties best suited to specific environmental conditions and management strategies. Unmanned aerial vehicles (UAVs) provide a promising means for phenotyping and offer the potential for new insights into relative plant performance. During a field trial exploring 141 quinoa accessions, a UAV-based multispectral camera was deployed to retrieve leaf area index (LAI) and SPAD-based chlorophyll across 378 control and 378 saline-irrigated plots using a random forest regression approach based on both individual spectral bands and 25 different vegetation indices (VIs) derived from the multispectral imagery. Results show that most VIs had stronger correlation with the LAI and SPAD-based chlorophyll measurements than individual bands. VIs including the red-edge band had high importance in SPAD-based chlorophyll predictions, while VIs including the near infrared band (but not the red-edge band) improved LAI prediction models. When applied to individual treatments (i.e. control or saline), the models trained using all data (i.e. both control and saline data) achieved high mapping accuracies for LAI (R2?=?0.977–0.980, RMSE?=?0.119–0.167) and SPAD-based chlorophyll (R2?=?0.983–0.986, RMSE?=?2.535–2.861). Overall, the study demonstrated that UAV-based remote sensing is not only useful for retrieving important phenotypic traits of quinoa, but that machine learning models trained on all available measurements can provide robust predictions for abiotic stress experiments.

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