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91.
Despite the importance of mucilage for soil–plant relations, little is known about the effect of soil drying on mucilage exudation. We introduce a method to collect mucilage from maize growing in wet and dry soils. Mucilage was collected from brace roots. The amount of mucilage exuded did not change with soil water content and transpiration rate. Mucilage exuded in dry soils had a higher degree of hydrophobicity, suggesting that the wetting properties of mucilage change in response to soil drying.  相似文献   
92.
In plants, zinc is commonly found bound to proteins. In barley (Hordeum vulgare), major storage proteins are alcohol‐soluble prolamins known as hordeins, and some of them have the potential to bind or store zinc. 65Zn overlay and blotting techniques have been widely used for detecting zinc‐binding protein. However, to our knowledge so far this zinc blotting assay has never been applied to detect a prolamin fraction in barley grains. A radioactive zinc (65ZnCl2) blotting technique was optimized to detect zinc‐binding prolamins, followed by development of an easy‐to‐follow nonradioactive colorimetric zinc blotting method with a zinc‐sensing dye, dithizone. Hordeins were extracted from mature barley grain, separated by SDS‐PAGE, blotted on a membrane, renatured, overlaid, and probed with zinc; subsequently, zinc‐binding specificity of certain proteins was detected either by autoradiography or color formation. The dithizone staining method gave similar reproducibility to the radioactive blotting. The detected zinc‐binding protein was identified as B‐hordein by Western blotting.  相似文献   
93.
B-mode ultrasonography using a 7.5 megahertz (MHz) transducer was performed on 95 equine cadaver eyes submerged in a water bath. Identification and measurement of the anterior to posterior diameters of the intraocular structures and of the axis bulbi was done. The dorsal ventral axis of the eye was also measured. The eyes were then frozen, sectioned in a saggital plane and the same measurements were made using calipers. Two sets of measurements were then compared statistically.
With the exception of the cornea and the dorsal ventral axis measurements of male horses there was no statistically significant difference in the measurements obtained by the two methods.
The use of B-mode ultrasonography at a frequency of 7.5 MHz to examine the architecture of the equine eye is suggested as a valuable clinical tool. Biometry of the intraocular structures at this frequency may be reasonably accurate.  相似文献   
94.
95.
Male and female Japanese quail (Coturnix coturnix japonica) were given intraperitoneal injections of [14C]DDT in ethanol at a rate of 13.4 mg/kg body wt. Fifty-six days later the tissues and droppings were analysed for total 14C and metabolites. The rate of loss of 14C in droppings was very similar in males and females. The maximal rate was reached on the third day, and 65–66% of the injected dose was voided by the fifty-sixth day. Ninety-three to ninety-four percent of the 14C in droppings and 83–90% of the 14C in tissues were extracted by solvents. Combined extracts from males and females were used for determination of DDT and its metabolites. Expressing all results as percentages of injected dose, the following were isolated from droppings: DDA (24%), DDT (3%), DDD (5.1%), DDE (11%), and uncharacterised polar metabolites (17%). Twenty-five percent of the dose was retained in the tissues and this was largely accounted for as DDT (10.4%) and DDE (10.5%). Of the total metabolites found 31% was DDE (almost equally divided between tissues and droppings) and 35% was DDA (almost entirely in droppings). Since DDD was not found in significant quantities in tissues, the substantial quantities in droppings were probably produced from DDT by the action of microorganisms.  相似文献   
96.
Despite the intensive management and husbandry precautions, exotic pregnant heifers imported to the Gezira, Sudan, suffered excessive stress. Four of five heifers aborted due to stress. Death was due to pasteurellosis, babesiosis and heart water.  相似文献   
97.
98.
Contents: The onset and progression of goat fetal skeletal radio opacity were studied to identify the stage of pregnancy and the number of fetuses present. Lateral radiographs using 75 KVP, 200 Ma, 0.25 s and 100 FFD was found to be good values for detection of pregnancy in goats. Lengths taken for skull, femur and vertebral column of the fetus were used as a parameter for determination of the stage of pregnancy. Counting the number of fetal skulls were used for estimating the number of fetuses present. Accurate radiological diagnosis of pregnancy in goat was possible after 10 weeks of gestation .
Inhalt: Radiographische Bestimmung der Trächtigkeit bei der Ziege
Der Beginn und die Weiterentwicktung fötater Skelettbildung wurde radiologisch bestimmt, um das Stadium der Trächtigkeit und die Zahl der Föten zu ermitteln. Laterale Röntgenbilder wurden mit 75 KVP, 200 Ma., 0,25 Sek. und 100 FFD ermittelt, wobei sich diese Einstellung als günstig für die Trächtigkeitserkennung bei Ziegen erwies. Die Ermittlung der Schädellänge, des Femurs und des Rückenmarks beim Fötus wurden als Parameter für die Bestimmung des Trächtigkeitsstadiums benutzt. Die Zahl der Fötalschädel ergab die Zahl der Föten. Genaue radiologische Diagnose der Trächtigkeit bei Ziegen war ab etwa 10 Wochen der Trächtigkeit möglich .  相似文献   
99.
Extracellular products in culture filtrates of Aeromonas salmonicida subsp. achromogenes and Vibrio anguillarum isolated from infected fish have been shown to possess skin inflammatory factor. The extracellular products from Vibrio anguillarum were cytotoxic in HeLa and CHO cells. In addition to the skin lesions, the culture filtrates of V. anguillarum caused necrotic reaction on the rabbit skin. Five of 6 strains of V. anguillarum were lethal to mice after intraperitoneal administration of 3×107 CFU. Only 1 strain of 5 A. salmonicida subsp. achromogenes produced extracellular products which elicited cytotoxic effects in the CHO cells. None of the A. salmonicida subsp. achromogenes strains were lethal to mice. The cytotoxins were inactivated when heated at 65°C for 30 min. The results indicate that the thermolabile exotoxins are non-enterotoxic since they failed to stimulate fluid accumulation in the rabbit ileal loop and did not cause elongation of the CHO cells. The rounding off of CHO cells, as well as of HeLa cells indicate that the exotoxins may play an important role in fish diseases.  相似文献   
100.
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