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991.
992.
It has been reported previously that populations with a decreased concentration of fecal bile acids have a lower incidence of colon cancer. We examined the importance of fecal bile acid dilution by wheat bran (WB) in inhibiting colonic tumorigenesis in an experimental animal model. Male F344 rats received oral doses of the colon carcinogen 1,2-dimethylhydrazine [CAS: 540-73-8] and were assigned randomly to groups fed one of four semipurified diets for 26 weeks. The diets were fiber-free (FF), 10% WB, FF + bile salts, or WB + bile salts. The amount of bile salts added was adjusted to produce a fecal bile acid concentration in the group fed WB + bile salts equal to that found in the FF groups. Fecal bile acid concentrations at 12 and 24 weeks in the WB + bile salts group were similar to those in the FF group. Gross and microscopic findings at necropsy revealed a reduced total number and multiplicity of colon tumors in both bran-fed groups. Although the fecal bile acid concentrations of the FF and WB + bile salts groups were equal, the latter showed a significant reduction in tumor yield.  相似文献   
993.
Chlamydia trachomatis recently has emerged as the most frequently diagnosed sexually transmitted disease (STD) agent. An estimated three million cases are diagnosed annually in the United States. Because the infection is not reportable, only estimates can be made. The most common STD, it also is often transmitted to infants through infected mothers. Prevention and treatment of the disease in newborns require different procedures from those for gonorrhea, as do diagnostic and treatment methods for infected adults. Chlamydia also appears to pose a threat to pregnancy.  相似文献   
994.
Twenty patients (15 males; five females) aged 11-70 years, with urinary tract infections were treated with one 250 mg tablet of ciprofloxacin every 12 h for 5-10 days. Clinical response to this treatment was the complete disappearance of symptoms in 85% of cases and the elimination of the micro-organism responsible for infection. In only three patients, who all had urinary calculus in addition to an infection, clinical failure of the therapy occurred and the causative micro-organism persisted. Tolerance to the therapy was excellent in this study, no adverse reactions connected with the treatment being reported.  相似文献   
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External enhancement of free-radical processes followed by considerable tissue accumulation of toxic lipid peroxidation products in an early postresuscitation period is the main pathochemical mechanism which causes lung air-blood barrier disturbance. The basis of animal respiratory insufficiency morphogenesis after clinical death is ventilation failure (dis- and atelectasis), circulation disorder (edema, hemorrhage) being secondary. However, morphological examination of lungs of animals after four-minutes clinical death from an acute blood loss and resuscitation showed that it is the severity of circulation disorders that determines the animals condition in the postresuscitation period.  相似文献   
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