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11.
Smokeless tobacco use is a significant health risk for carcinoma of the oropharynx, and has a high prevalence in the southern United States. To evaluate the potential demand for a smokeless tobacco cessation program, we surveyed patients attending the General Medicine Clinic of a Veterans Affairs Medical Center. The prevalence of smokeless tobacco use was 5.8%, which did not justify creation of a clinic-based cessation program. Since we observed adults using smokeless tobacco as a means to reduce or stop their smoking, smoking cessation programs should include counseling against smokeless tobacco use. 相似文献
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The results of an investigation into the effects of the magnetic processing procedure on the intrinsic coercivity of a Sm(Co0.673Cu0.080Fe0.222Zr0.025)8.92 (217-type) alloy are reported. Two basic types of magnet were investigated: polymer-bonded fine powder magnets and cast (solid) magnets. The fine particles which were processed into polymer-bonded magnets were prepared by two different methods; i.e. by milling or by a hydrogen treatment. The cast magnets were manufactured from selected parts of solidified ingots exhibiting preferrred orientation and along directions parallel to the preferred orientation of magnetization. Magnetic properties and Vickers microhardness measurements on the solid solution treated (1170° C) and isothermally aged (800° C) samples, revealed that there was a clear similarity between the variations of the intrinsic coercivity and microhardness values versus ageing period. This suggests a coercivity mechanism for the present 217-type alloy which is predominantly controlled by general domain wall pinning by a critical dispersion of coherent precipitates. Certain aspects of the intrinsic coercivity against ageing time variations of the variously processed magnets as well as the corresponding microhardness variations have been attributed to a partial conversion of coherent precipitates to semi- or in-coherent particles during processing. 相似文献
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The rôle of carboxyl proteases in tenderising meat was investigated by injecting the inhibitors, pepstatin and EPNP, into pre-rigor muscle. The increase in shear force values induced by these inhibitors provided a minimum estimate of the extent to which endogenous carboxyl proteases normally tenderise meat at 60°C.Gel electrophoresis showed that connectin was hydrolysed to a greater extent than other muscle proteins at this temperature and that breakdown of connectin was inhibited by pepstatin and EPNP. Thus it is likely that, when intact, connectin may contribute to the strength of cooked meat. 相似文献