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1.
Xanthomonas fragariae spreads in symptomlessly infected strawberry plantlets and a method for detection of latent infections is necessary. It is a very slow‐growing bacterium in culture and is easily overgrown by saprophytic bacteria. Therefore, plating is not a suitable method for detecting low numbers of bacteria in symptomless plants. In addition, selective media are not available. Serological assays like immunofluorescence are useful for testing in‐vitro plants, but they are not suitable for field‐grown plants, as cross reactions are common with the available antisera. For these plants, nested PCR with primers from Pooler ( Pooler et al., 1996 ) and Zimmermann ( Zimmermann et al., 2004 ) has proved to be a valuable method. The method was successfully applied for a survey of strawberry plants from fields in Germany and for testing imported plants (frigo and green plants).  相似文献   
2.
The use of Trichogramma egg parasitoids has further increased. T. brassicae, released against the European Corn Borer Ostrinia nubilalis, holds the largest share in Germany with 11,000 hectare. For small-scale fruits crops the commercial use of T. cacoeciae and T. dendrolimi against the Codling Moth (Cydia pomonella) and the Plum Moth (Grapholita funebrana) has been expanded. Trichogramma species are also being offered for controlling the vine moths, Lobesia botrana and Eupoecilia ambiguella on grapevine in homegardens. A strain of T. evanescens is available against cabbage pests, especially noctuids. Research has been conducted on the biological control of Autographa gamma in spinach, as well as of the Pea Moth (Cydia nigricana) and the Leek Moth (Acrolepiopsis assectella) in organic farming. Trichogramma is also important for the biocontrol of exotic pests in greenhouses. These are often polyphagous pests that have been introduced together with ornamental plants, such as Duponchelia fovealis and Clepsis spectrana. The Carnation Tortrix (Cacoecimorpha pronuba) was successfully controlled by Trichogramma in the field. The use of Trichogramma has been further established for the control of storage pests. T. evanescens is used against the Indian Meal moth (Plodia interpunctella) in stored cereal products. Other target pests in storage environments are Ephestia kuehniella and Sitotroga cerealella. In addition, Trichogramma species have been tested for the control of the Common Cloths Moth (Tineola bisselliella) under laboratory conditions. The range of target pests for Trichogramma egg parasitoids has therefore increased considerably in research and commercial applications in Germany.  相似文献   
3.
Cutaneous leiomyosarcomas are malignant mesenchymal tumors of smooth muscle origin and are reported occasionally in avian species. A 14-y-old male laboratory White Carneau pigeon (Columba livia) was presented for surgical excision of a cervical soft tissue mass. Ultrasonography with color flow Doppler imaging revealed multiple cavitations of mixed echogenicity within the mass and vascularization. Histologically, the dermis and subcutis were expanded by a densely cellular multinodular mass comprised of fusiform cells forming haphazardly arranged broad streams and short interwoven bundles, often surrounding blood vessels and variably sized cavitations. Neoplastic cells were strongly immunopositive for desmin and α–smooth muscle actin, and negative for pancytokeratin, S100, and von Willebrand factor. Based on histopathology and IHC findings, the cutaneous mass was diagnosed as leiomyosarcoma (LMS). The pigeon died 312 d post-operatively. Postmortem examination revealed masses infiltrating the left and right pulmonary airways and one hepatic nodule, but no regrowth at the surgical site. Histologic and IHC evaluation of the pulmonary and hepatic masses were consistent with LMS, representing metastatic foci from the primary cutaneous LMS. Our case highlights the malignant behavior and histomorphologic features of cutaneous LMS in an avian species.  相似文献   
4.
Table grapes (Vitis vinifera L. cv. Crimson Seedless) were coated with Aloe vera gel according to our developed patent (SP Patent P200302937) and then stored for 35 days at 1 degrees C, and the subsequent shelf life (SL) was monitored at 20 degrees C. Uncoated clusters showed a rapid loss of functional compounds, such as total phenolics and ascorbic acid. These changes were accompanied by reduction of the total antioxidant activity (TAA) and increases in total anthocyanins, showing an accelerated ripening process. On the contrary, table grapes coated with Aloe vera gel significantly delayed the above changes, such as the retention of ascorbic acid during cold storage or SL. Consequently, Aloe vera gel coating, a simple and noncontaminating treatment, maintained the functional properties during postharvest storage of table grapes.  相似文献   
5.
J Stone  M Fabian 《Science (New York, N.Y.)》1966,152(726):1277-1279
Three new types of receptive field have been found in the cat's retina. The responses of these fields to flashing lights and moving objects suggest that the manner in which they code visual information may be quite different from that of the center-surround fields described in previous studies. These "specialized" fields were all found in the area centralis. A definite functional difference, corresponding to the known anatomical difference, between this region and the rest of the retina, is suggested.  相似文献   
6.
Ohne Zusammenfassung Mit 2 Abbildungen.  相似文献   
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8.
Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, anti-viral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for COVID-19 recovery. This work aimed to determine the ex-vivo effects of treatment with fucoidan (20 µg/mL) on mitochondrial membrane potential (ΔΨm, using a cationic cyanine dye, 3,3′-dihexyloxacarbocyanine iodide (DiOC6(3)) on human peripheral blood mononuclear cells (HPBMC) isolated from healthy control (HC) subjects, COVID-19 patients (C-19), and subjects that recently recovered from COVID-19 (R1, 40 ± 13 days after infection). In addition, ex-vivo treatment with fucoidan (20 and 50 µg/mL) was evaluated on ΔΨm loss induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP, 150 µM) in HPBMC isolated from healthy subjects (H) and recovered subjects at 11 months post-COVID-19 (R2, 335 ± 20 days after infection). Data indicate that SARS-CoV-2 infection induces HPBMC loss of ΔΨm, even 11 months after infection, however, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered subjects. Therefore, fucoidan may be a potential treatment to diminish long-term sequelae from COVID-19, using mitochondria as a therapeutic target for the recovery of cellular homeostasis.  相似文献   
9.
Rice culture of a toxigenic strain of Aspergillus ochraceus was fed at a concentration of 25% to weanling pigs for 10 days. The clinicopathological abnormalities reflected renal damage. Activities of lactic dehydrogenase, glutamic-oxaloacetic transaminase and isocitrate dehydrogenase were increased in the urine but not in the serum. Serum concentrations of urea nitrogen and creatinine were high. Cellular and granular casts, blood, protein, and glucose were in the urine of pigs fed toxic diet. Serum concentrations of K+, Na+ and Cl- were unchanged, but concentrations of these electrolytes were reduced in the urine.  相似文献   
10.
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