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21.
In this study dealing with the development of management strategies for P. ramorum in Rhododendron stands several plant protection and fertilizer products were tested for their suitability to control this pathogen on Rhododendron. Tests were conducted on young potted plants and abscised leaves, using the following products: phosphite (Nutri-Phite® PK), copper hydroxide (Cuprozin® liquid), Bacillus subtilis (Serenade®), a mycorrhizal preparation, and a product based on ‘effective microorganisms’ (EMa). Although transmission of the pathogen from infected to healthy plants was successfully inhibited by phosphite, Cu hydroxide and B. subtilis, subsequent tests showed that only phosphite and Cu hydroxide had a significant effect on disease development. All other preparations based on antagonistic or growth promoting microorganisms had no preventive or curative effect. While B. subtilis tended to increase disease symptoms, the remaining products caused a slight reduction of disease severity only. In contrast, phosphite and Cu hydroxide almost completely inhibited infection by P. ramorum. Therefore, in field situations, the use of the ecologically safe, systemic phosphite against P. ramorum in Rhododendron stands appears to be reasonable and advisable. Along with other supporting measures within the framework of a management strategy, this will allow to prevent or slow down further spread of the disease.  相似文献   
22.
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients.  相似文献   
23.
Chronic exposure to ultraviolet (UV) light promotes the breakdown of collagen in the skin and disrupts the extracellular matrix (ECM) structure, leading to skin wrinkling. Pacific whiting (Merluccius productus) is a fish abundant on the Pacific coast. In the current study, we investigated the anti-wrinkle effect of hydrolysate from Pacific whiting skin gelatin (PWG) in UVB-irradiated human dermal fibroblasts and the molecular mechanisms involved. PWG effectively restored type 1 procollagen synthesis reduced by UVB-irradiation. Also, we found that PWG inhibited collagen degradation by inhibiting MMP1 expression. Furthermore, PWG decreased cytokines TNF-α, IL-6, and IL-1β associated with inflammatory responses and increased antioxidant enzymes, HO-1, SOD, GPx, CAT, and GSH content, a defense system against oxidative stress. In terms of molecular mechanisms, PWG increased collagen synthesis through activating the transforming growth factor β (TGF-β)/Smad pathway and decreased collagen degradation through inhibiting the mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1) pathway. It also suppressed the inflammatory response through suppressing the nuclear factor-κB (NF-κB) pathway and increased antioxidant enzyme activity through activating the nuclear factor erythroid 2/heme oxygenase 1 (Nrf-2/HO-1) pathway. These multi-target mechanisms suggest that PWG may serve as an effective anti-photoaging material.  相似文献   
24.
Growth of the cellulose-synthesizing bacterium Acetobacter xylinum ATCC 53524 in media supplemented with 5% (w/v) glucose and 0.2% (w/v) of a water-soluble, nearly linear xylan from tobacco stalks resulted in the synthesis of a highly crystalline composite having a xylose/glucose ratio ranging from 0.06 to 0.24. The digestion of one composite (88% cellulose/12% xylan) by mixed ruminal microflora displayed kinetics of gas production similar to those of an unassociated mixture of the two components added in a xylan/cellulose ratio similar to that of the composite. The data suggest that intimate association of xylan and cellulose, as is typically found in secondary plant cell walls, does not inhibit the rate of digestion of the component polysaccharides.  相似文献   
25.
Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.  相似文献   
26.
Germanium biotite (GB) is an aluminosilicate mineral containing 36 ppm germanium. The present study was conducted to better understand the effects of GB on immune responses in a mouse model, and to demonstrate the clearance effects of this mineral against Porcine reproductive and respiratory syndrome virus (PRRSV) in experimentally infected pigs as an initial step towards the development of a feed supplement that would promote immune activity and help prevent diseases. In the mouse model, dietary supplementation with GB enhanced concanavalin A (ConA)-induced lymphocyte proliferation and increased the percentage of CD3+CD8+ T lymphocytes. In pigs experimentally infected with PRRSV, viral titers in lungs and lymphoid tissues from the GB-fed group were significantly decreased compared to those of the control group 12 days post-infection. Corresponding histopathological analyses demonstrated that GB-fed pigs displayed less severe pathological changes associated with PRRSV infection compared to the control group, indicating that GB promotes PRRSV clearance. These antiviral effects in pigs may be related to the ability of GB to increase CD3+CD8+ T lymphocyte production observed in the mice. Hence, this mineral may be an effective feed supplement for increasing immune activity and preventing disease.  相似文献   
27.
In a feeding experiment (54 piglets) and a slaughtering test for the registration of tract and digesta properties (15 piglets) the influence of rations with 69% rye (R) or wheat (W) with and without a supplement of 200 mg of the chinoxalin derivate Bisergon/kg DM (rations RB and WB) was studied. In the sequence R, RB, W and WB the feed intake in the test period of 3 weeks after weaning amounted to 581, 651, 583 and 764 g, weight gain to 314, 365, 319 and 424 g per animal and day. In the same sequence the concentration of organic acids in the stomach amounted to 41, 5, 25 and 18 mmol per 100 g dry matter and in the colon to 106, 83, 64 and 62. Bisergon caused a redistribution of the digesta from the stomach to the large intestine and a more rapid emptying of the stomach as well. Rye caused extreme fermentation processes in the front part of the tract and Bisergon clearly has ergotropic qualities for the stabilization of the intestinal flora.  相似文献   
28.
With a view to studying the effect of acid addition, weaned piglets and fattening pigs were fed graduated amounts of protein mixed silage (pH-value 3.15 by adding 20 g H2SO4/kg) in rations of equal energy and protein levels. On average, the fattening pigs were taking in 0.26 g H2SO4/kg, whilst the amounts for piglets were 0.60 and 0.72 g H2SO4/kg. Higher acid intakes had a negative effect of energy expenditure, weight gains and feed intake. The experimental animals had significantly longer small intestines, whilst the intestine's wall was found thinner and the amount of digesta reduced and with a higher water content. The microbial activity in the stomach proved significantly inhibited. However, it was higher in the caecum as compared to the control animals. Metabolic parameters suggest that water and mineral balances are under stress. The significance of acid addition for tract flora and its metabolites is discussed. Protein mixed silage is regarded a dietetically favourable feed when given at a maximum daily amount of 25 g/kg LW or 1 kg/animal. The recommendation for dosing the daily administration of inorganic acids is as follows: max. 0.5 g acid/kg LW or 20 g/animal.  相似文献   
29.
30.
A 16-year-old, castrated, male English cocker spaniel dog was presented due to generalized alopecia. Routine clinical pathology, endocrine and abdominal ultrasonography results were consistent with a diagnosis of pituitary-dependent hyperadrenocorticism. The adenohypophyseal lesion was clearly visualized on both 3 T and 7 T magnetic resonance imaging (MRI) of the pituitary gland. Although biochemical and MRI findings were consistent with a functional pituitary microtumor, a pituitary lesion was not detected using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). This report firstly describes the application of high-resolution FDG-PET to a spontaneous pituitary microtumor in a dog.  相似文献   
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