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721.
722.
Research on the implementation of comprehension-strategies instruction is discussed briefly. The particular focus is on the challenges educators have encountered in translating research-based strategies instruction into workable, school-based interventions and, ultimately, into classroom practice. The research outcomes reviewed here are consistent with Gersten, Vaughn, Deshler, and Schiller's (this issue) analysis, except that the present authors are a bit more sanguine about the fact that, in some settings, substantial progress already has been made in translating researcher-developed instruction into effective classroom instruction. Moreover, it is encouraging that there is a large body of research that is ready to be applied. 相似文献
723.
PB Rossiter 《Canadian Metallurgical Quarterly》1982,7(5):419-425
Rabbits hyperimmunized with inactivated malignant catarrhal fever virus (MCFV) infected rabbit lymph node cells did not develop specific antibodies to the virus and succumbed to challenge with live MCFV-infected lymphoid cells. Rabbits hyperimmunized with either inactivated or live, cultured bovine kidney cells infected with MCFV developed antibodies to the virus, but also succumbed to challenge with live MCFV-infected rabbit lymphoid cells. Rabbits hyperimmunized with live cultured rabbit kidney cells infected with MCFV developed antibodies to the virus and resisted challenge with live MCFV-infected rabbit lymphoid tissues 47 weeks later. However, rechallenge of this group at 90 weeks post immunization resulted in the death of 2/4 rabbits suggesting a waning immunity. 相似文献
724.
725.
The effect on canine otitis externa of a topical preparation composed of Fucidin, Framycetin, Nystatin, and Prednisolone was evaluated in a clinical trial comprising 235 dog ears. Cases caused by parasites or foreign bodies and cases requiring systemic therapy were excluded. Swabs from these and an additional 434 affected ears were examined bacteriologically and the sensitivity to antibiotics of the bacteria isolated determined. The infection most frequently diagnosed was staphylococci plus yeasts (29 % of total material) followed by pure yeast-infections (19 %) and pure staphylococcus infections (16 %). Pseudomonas aeruginosa and/or Proteus mirabilis were found in 7 % of the ears, while no organisms could be isolated from 22 %. Sensitivity tests showed a satisfactory in vitro effect of Neomycin (Framycetin) on most of the bacteria commonly isolated, and a very good effect of Fucidin on the staphylococci. Approximately 91 % of the ears treated were clinically cured or improved very considerably; the relation between clinical response and type of infection is shown diagrammatically in Fig. 1. It was confirmed that infections with Ps. aeruginosa represent a special problem; the results of post-treatment sensitivity tests seem to suggest, however, that a longer or more intense course of treatment than the one used in the trial (two weeks) would provide the answer to this. 相似文献
726.
Live but not fixed or heat-killed Borrelia burgdorferi bound to galactocerebroside, lactosylceramide, and ceramide trihexoside. In addition, this organism bound to the disialoganglioside GD1a and the trisialoganglioside GT1b but not to gangliosides GM1, GD1b, GM2, and GM3 and not to asialo GM1. This adhesion pattern confirmed earlier findings of binding to galactocerebroside and places this organism within a prokaryotic group which binds to lactosylceramide. The binding to GD1a and GT1b, both of which carry terminal as well as multiple sialic acids, indicates that B. burgdorferi can show specificity of binding within a group of acidic gangliosides. Adhesion could not be inhibited by several concentrations of sugars and sialic acid, indicating more complex binding requirements than for terminal carbohydrates alone. Low-passage strains adhered to the four substrates in greater numbers than strains in culture for long periods of time. OspB mutants in general bound better or at least equally well to several of the glycosphingolipids, and preincubation of substrates with soluble recombinant and affinity-purified Osp did not inhibitor or weakly inhibited the binding of the organisms. These findings suggest that outer surface lipoproteins A and B are not directly involved in adhesion to glycosphingolipids. 相似文献
727.
728.
PB Crevenna 《Canadian Metallurgical Quarterly》1976,18(2):409-420
An electron-capture gas chromatographic method is described for the determination of naloxone and naltrexone as the perfluoroalkyl esters. Each compound serves as internal standard for determination of the other. The method permits quantitation of 2-100 ng of either compound. Conditions for derivatization with heptafluorobutyric anhydride (HFBA), pentafluoropropionic anhydride (PFPA), and trifluoroacetic anhydride (TFAA) have been investigated. When catalyzed with pyridine, derivatization with HFBA and PFPA at 70 degrees gives naloxone and naltrexone triesters. Evidence for triester formation was obtained from gas chromatography-methane chemical ionization mass spectrometry and infrared spectral analysis. It was found that both the HFB and PFP triesters are suitable for quantitation of the narcotic antagonists, the HFB derivatives having greater stability than the PFP derivatives. The TFA derivatives are substantially less stable. 相似文献
729.
730.
DJ Schneider PB Tracy BE Sobel 《Canadian Metallurgical Quarterly》1998,33(5):107-10, 115-8, 121-4 passim
Therapies with novel antiplatelet agents and anticoagulants are the focus of current research. When used separately or in combination, these agents prevent generation of thrombin by activated platelets. The new therapies, in conjunction with judicious use of fibrinolytic drugs and mechanical interventions, are revolutionizing the management of patients with acute coronary syndromes. 相似文献