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991.
T M Hill S P Schmidt R W Russell E E Thomas D F Wolfe 《Journal of animal science》1991,69(11):4570-4576
To determine the effect of dry (D); reconstituted and ensiled (R); reconstituted and acid-treated (A); and urea-treated, high-moisture (U) sorghum grain on starch digestibility, four Angus x Hereford steers (means BW = 350 kg) with duodenal and ileal cannulas were used in a 4 x 4 Latin square design. Diets consisting of 69% ground sorghum grain were fed every 2 h in equal portions (8.2 kg/d). Diets averaged 46.5% starch and 12% CP, except for U, which averaged 14% CP due to urea treatment. Ytterbium attached to sorghum was used as a particulate marker. Duodenal, ileal, and fecal samples were taken 1 h postfeeding after a 14-d adaption to diets. Whole samples were analyzed. Preduodenal starch digestion (%) was 89, 83, 76, and 70, and starch digestion over the total tract was 99, 97, 95 and 91 for R, U, A, and D, respectively. Starch digestion proximal to each site (duodenum and ileum) was enhanced (P less than .05) by R and U compared with D. Within the small intestine, there was a linear relationship (P less than .003) between starch digestion and daily starch supply. However, digestibility of starch in the small intestine (mean = 45%) was not different among diets. Apparent digestibility of starch in the large intestine was not significantly different from digestibility in the small intestine. Urea-treated sorghum grain was equivalent to reconstituted, ensiled sorghum in digestion characteristics and was superior to dry sorghum. 相似文献
992.
993.
Chirality index, molecular overlay and biological activity of diastereoisomeric mosquito repellents 总被引:1,自引:0,他引:1
Both 1-methylisopropyl 2-(2-hydroxyethyl)piperidine-1-carboxylate, (Picaridin((R))) and cyclohex-3-enyl 2-methylpiperidin-1-yl ketone (AI3-37220; 220) have two asymmetric centers, and the four diastereoisomers of each compound are known to have differing degrees of mosquito-repellent activity according to quantitative behavioral assays conducted at the United States Department of Agriculture. Computational chemistry was used to identify the structural and configurational basis for repellent activity. Molecular overlay of the optimized geometries of the lowest energy conformers of the diastereoisomers was investigated to elucidate the role of chiral centers in 220 and Picaridin. It was found that the presence of a chiral carbon alpha to the nitrogen with the S configuration in the piperidine ring is essential to the three-dimensional arrangement of the atoms of the pharmacophore for effective repellent activity. 相似文献
994.
H. Schmidt 《Journal of pest science》1973,46(12):180-183
Summary Within the family Dermestidae (Bacon Beetles) the speciesDermestes maculatus (= D. vulpinus) has a world-wide distribution today and is well known as a household insect pest. The larvae of the Bacon Beetles bore holes for pupation in various soft materials, including wood. Here are given some observations on the biology of the adult and larva, especially concerning their nutrition. The study of the microscopic anatomy of the alimentary canals has shown that the adult and larva ofD. maculatus do not digest wood particles. Both eat mostly foodstuffs with a high fat content. 相似文献
995.
The transient change in conductivity in diluted barium hydroxide solutions during and immediately after irradiation with single pulses of electrons from a 15-million-electron-volt linear accelerator was measured. Ionic mobility of the radiation-produced hydrated electrons was 1.84 x 10(-3)cm(-2) volt(-1) sec(-1) +/- 10 percent. This value corresponds to a diffusion constant of 4.75 x 10(-5) cm(2) sec(-1). 相似文献
996.
997.
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999.
G Schmidt 《Tier?rztliche Praxis》1985,13(2):255-266
The history of araneidism is long and confusing. The superstition seems to be inexterminatable that tropical mygalomorphs and mediterranean tarantulas are dangerous for humans. It can be looked up even in the most recent edition of the widespread clinical dictionary of Pschyrembel. In contrast to this certain ctenids, the most dangerous spiders up to now known, are mentioned not at all in medical publications. Exaggerated spider-fear is out of place because about 0.1% of all species are dangerous for man only and many of the venomous species live as hidden as they scarcely come in contact with humans. 相似文献
1000.
Two large cysts recovered from the abdominal cavity of a domestic chicken superficially resembled hydatid cysts of Echinococcus spp. No protoscolices were present. Microscopic examination of the internal lining of one of the cysts revealed a single cuboidal to columnar, ciliated epithelium, leading to a diagnosis of oviduct cysts. Earlier records of hydatids of fowl are reviewed. 相似文献