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161.
Susanne M. Stieger Christian Wenker Daniela Ziegler-Gohm Mark Flückiger PHD 《Veterinary radiology & ultrasound》2003,44(3):326-329
A 5-year-old guinea pig with suspected urolithiasis was presented for radiology and ultrasound examinations of the abdomen. Radiographically, an irregular-shaped mineral opacity was detected in the area of the urinary bladder. Ultrasonographically, pyelectasia of the right kidney, hydroureter with an ureterolith cranial to a thickened ureter wall close to the ureterovesical junction, and a thickened urinary bladder wall were detected. Histopathologically, the thickened ureter wall was found to be a papilloma. The ureter calculus consisted of 100% calcite. 相似文献
162.
Christian Walzer DVM Katharina Hittmair DVM Christa Walzer-Wagner DVM 《Veterinary radiology & ultrasound》1996,37(4):289-292
A total of 44 live cheetahs were examined sonographically between 1989 and 1994. Seventeen of these animals originated from 4 European facilities, the other 27 cheetahs were examined in 3 facilities in Namibia. Evaluation of the cheetahs included a clinical examination, abdominal ultrasound, and complete blood work. Splenic myelolipomas were diagnosed sonographically in 11 cheetahs. In 7 cheetahs the diagnosis was confirmed at necropsy. Nine of the 14 cheetahs in Europe had myelolipomas in the spleen, while in the African cheetahs there were only 2 animals with myelolipomas. Histologically these lesions were characterized by fatty nodules. A more fitting term of Nodular Lipomatosis of the spleen is therefore suggested. All cheetahs with nodular lipomatosis of the spleen, had concurrent chronic diseases at necropsy. An indicator function of splenic nodular lipomatosis for chronic disease and/or stress is possible. 相似文献
163.
Christian Friis 《Veterinary research communications》1983,7(1):349-352
The renal excretion of organic acids involves three mechanisms: glomerular filtration, active tubular secretion and passive tubular reabsorption. The postnatal development of each of these mechanisms was assessed in piglets. From birth to 8 weeks of life glomerular filtration rate (GFR) and clearance of p-amino-hippurate (PAH) rose twofold while the maximal tubular secretion of PAH (TmPAH) rose fourfold. Thus, the active secretion increased in parallel with GFR when the transport mechanism was unsaturated, whereas it increased about twofold more than GFR at saturation point. Age differences in the passive reabsorption were evaluated by using sulphachlorpyridazine (SCP) as test substance. Although the renal handling of SCP includes both secretion and reabsorption, the age-dependent rise in the ratio between clearance of ultrafiltrable SCP and GFR indicated a relative decrease in reabsorption with age. 相似文献
164.
Zusammenfassung Von 380 Winter- und 1400 Sommergersten des Sortiments Gatersleben wurde in Halle das Verhalten gegen die virulente Rasse 24 vonPuccinia striiformis West, untersucht. Als hochresistent erwiesen sich 5 Winter- und 43 Sommerformen. Ein großer Teil dieser Sommergersten, darunter auch wertvolle Kombinationen von Gelbrost- mit Zwergrost- bzw. Mehltauresistenz, stammen aus Aethiopien. Resistenz zeigten weitere 88 Proben oder ca. 5% des Sortiments. In 12% lagen Gemische anfälliger mit resistenten Pflanzen vor. 80% der Gersten waren mäßig bis stark anfällig für Gelbrost.
Summary Stripe rust reaction of 380 winter and 1400 spring barley varieties of the Gatersleben collection was tested in the greenhouse as well as in the disease nursery by artificial infection with the virulent race 24 ofPuccinia striiformis West. Five winter and 43 spring barley varieties have proved to be highly resistant. A large number of the latter were collected in Ethiopia, among them are useful combinations of stripe rust with dwarf rust resistance and mildew resistance, respectively. Resistance was shown by other 88 varieties or by about 5% of the total. Susceptible as well as resistant plants were found in 12% of the samples. 80% of the varieties were moderately or highly susceptible to stripe rust.
am ¶rt;au 380 1400 24 . 5 43 . ¶rt; , , . 88 5% . 12% . 80% .相似文献
165.
Zusammenfassung In einer ersten Mitteilung werden aus dem Sortiment röntgeninduzierter Mutanten der Sojabohnensorte Heimkraft I 19 Mutanten nach ihren Hauptmerkmalen benannt und in das morphologische System der Sojabohne,Glycine max (L.) Merr. eingeordnet. Die Mutanten haben die taxonomische Rangstufe einer Linie (der gleiche Rang wie Sorte bzw. Cultivar). Sie können 8 verschiedenen Varietäten der Art zugeordnet werden.
Summary Within a first report 19 X-ray induced mutants of the soybean variety Heimkraft I are named according to her main characters and integrated into he morphological system of the soybean,Glycine max (L.) Merr. The mutant lines are of the same level as cultivar (variety). They are placed in 8 different varieties (varietates).
a I ¶rt; 19 , . Glycine max (L.) Merr. . .相似文献
166.
167.
Stein Nilsen Kirsti Hovland Christian Dons Sonja Prehn Sletten 《Scientia Horticulturae》1983,20(1):1-14
Net photosynthesis of tomato plants was measured as CO2 uptake in various light intensities, CO2 concentrations, O2 concentrations and temperatures during short-term experiments. Net photosynthesis increased significantly with increasing CO2 concentration at all light intensities, even at the lowest one. The optimal temperature for photosynthesis increased with CO2 enrichment. The changes in photosynthesis when the ratio was varied suggest that the effect of CO2 enrichment is a result of a reduction in photorespiration.To determine whether the increase in photosynthesis caused by CO2 enrichment would produce a greater yield, tomato plants were cultivated from seed to harvest in a tightly-closed greenhouse that was enriched with CO2 continuously during the entire growing-period. The control greenhouse was ventilated by openings in the roof and door. The temperature of the 2 greenhouses was kept the same. Plants enriched with CO2 showed a significant increase in fresh and dry weight and yield of tomatoes. The results are discussed in relation to earlier work in which CO2 enrichment was discontinued when there was a need for ventilation. 相似文献
168.
169.
Pillonel C 《Pest management science》2005,61(11):1069-1076
The effects of diverse phenylaminopyrimidines (PAP), namely PAP-pyridines (type A), PAP-pyrazoles (type B) and PAP-thiazoles (type C), on Neurospora crassa Shear & Dodge has been investigated. The results revealed that type A strongly inhibit the in vitro growth of N crassa, whereas types B and C are much less active. A significant correlation was observed between the Neurospora growth inhibition and the intrinsic activity of type A compounds on the cyclin-dependent protein kinase p34(CDC2) of starfish, suggesting that the target of phenylaminopyrimidines in fungi is a cyclin-dependent protein kinase (CDK). The phenylaminopyrimidine-binding CDKs Phoss (major band) and CDC2 (minor band) involved in phosphorus uptake, glycogen synthesis and the cell cycle were identified from N crassa by affinity chromatography on phenylaminopyrimidine-sepharose. Comparative experiments with different protein kinases revealed the importance of the side chain of phenylaminopyrimidines for their target selectivity. A type B compound was found to selectively inhibit the MAP-kinase OS-2 involved in the osmoregulatory pathway of Neurospora. 相似文献
170.
Rabea EI Badawy ME Rogge TM Stevens CV Höfte M Steurbaut W Smagghe G 《Pest management science》2005,61(10):951-960
Chitosan, the N-deacetylated derivative of chitin, is a potential biopolysaccharide owing to its specific structure and properties. In this paper, we report on the synthesis of 24 new chitosan derivatives, N-alkyl chitosans (NAC) and N-benzyl chitosans (NBC), that are soluble in dilute aqueous acetic acid. The different derivatives were synthesized by reductive amination and analyzed by 1H NMR spectroscopy. A high degree of substitution (DS) was obtained with N-(butyl)chitosan (DS 0.36) at a 1:1 mole ratio for NAC derivatives and N-(2,4-dichlorobenzyl)chitosan (DS 0.52) for NBC derivatives. Their insecticidal and fungicidal activities were tested against larvae of the cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), the grey mould Botrytis cinerea Pers (Leotiales: Sclerotiniaceae) and the rice leaf blast Pyricularia grisea Cavara (Teleomorph: Magnaporthe grisea (Hebert) Barr). The oral feeding bioassay indicated that all the derivatives had significant insecticidal activity at 5 g kg(-1) in artificial diet. The most active was N-(2-chloro-6-fluorobenzyl)chitosan, which caused 100% mortality at 0.625 g kg(-1), with an estimated LC50 of 0.32 g kg(-1). Treated larvae ceased feeding after 2-3 days; the mechanism of action remains unknown. In a radial hyphal growth bioassay with both plant pathogens, all derivatives showed a higher fungicidal action than chitosan. N-Dodecylchitosan, N-(p-isopropylbenzyl)chitosan and N-(2,6-dichlorobenzyl)chitosan were the most active against B cinerea, with EC50 values of 0.57, 0.57 and 0.52 g litre(-1), respectively. Against P grisea, N-(m-nitrobenzyl)chitosan was the most active, with 77% inhibition at 5 g litre(-1). The effect of different substitutions is discussed in relation to insecticidal and fungicidal activity. 相似文献