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For the past 10 to 15 years, radiation therapy and chemotherapy have played an increasingly important role in the treatment of various gastrointestinal malignancies, most prominently in anal and rectal cancer. Critical issues in the care of patients with anal and rectal cancer include not only local control and survival but organ preservation as well. For patients with carcinoma of the anal canal, external-beam irradiation with 5-fluorouracil and chemotherapy with mitomycin C have replaced surgery as primary therapy. Current studies are optimizing this therapy. In contrast, the management of distal rectal cancer is in evolution. Although the abdominoperineal resection has been long regarded as the definitive treatment of distal rectal cancer, it is associated with substantial morbidity (loss of anorectal function with a permanent colostomy and a high incidence of sexual and genitourinary dysfunction). As an alternative, treatment programs utilizing sphincter-preserving procedures with radiation therapy and chemotherapy are under active investigation. In selected patients, these strategies appear promising, and there have been reports of satisfactory local control and survival, as well as preservation of sphincter integrity.  相似文献   
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In a 63-year-old woman with longstanding type I diabetes mellitus, CAD and chronic heart failure, a subacute myocardial infarction developed, together with decompensation of cardiac function and diabetes and concurrent pneumonia. Acute heart failure with acute renal failure on top of diabetic nephropathy, and interstitial pulmonary edema was initially treated with hemofiltration and catechol amines together with antibiotic and perfusor-regulated insulin therapy, and systemic heparinization. Subsequent chronic treatment with digitalis, acetyl salicylic acid, insulin and a combination of an ACE inhibitor and a loop diuretic resulted in an improvement of heart failure to NYHA functional class II where PTCA of coronary multi-vessel disease could be performed with low risk.  相似文献   
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Three studies were conducted to evaluate amino acid utilization by cattle. In Exp. 1, five steers (580 kg) were fed 86% rolled corn diets with mixtures of amino acids containing up to 6 g/d DL-Met, 24 g/d L-Lys, 6 g/d L-Thr, and 3 g/d L-Trp. Treatments had little effect on ruminal fermentation, diet digestibility, N flow to the duodenum, or microbial efficiency. Ruminal concentrations of Met and Lys increased linearly (P < .05) with amino acid supplementation, whereas Thr responded quadratically, and Trp was not altered. In Exp. 2, four steers (414 kg) were used to measure effects of dietary monensin or laidlomycin propionate in high-grain diets supplemented with amino acids. Ionophores had no significant effect on ruminal fermentation or outflows of amino acids from the rumen. In Exp. 3, 100 steers (287 kg initial BW) were fed diets containing 1% of a nonprotein N source. Treatments were 1) no supplemental N (UREA), 2) UREA plus soybean meal (SBM), 3) UREA plus 2 g/d DL-Met, 8 g/d L-Lys, 2 g/d L-Thr, and 1 g/d L-Trp, or 4) UREA plus 4 g/d DL-Met, 16 g/d L-Lys, 4 g/d L-Thr, and 2 g/d L-Trp. During the growing period (diets based on whole-plant milo silage), gains were higher for SBM-supplemented steers than for UREA steers and intermediate for steers supplemented with amino acids. Few significant differences in performance were observed among treatments during the finishing phase (diets based on dry-rolled corn) or for the entire experiment, but cattle fed SBM or amino acids tended to be fatter and have better marbling scores and quality grades. Amino acids did not greatly alter ruminal fermentation or cattle performance.  相似文献   
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BACKGROUND: The sensitivity of diagnostic imaging of processes in the parotid gland has been increased by improved spatial resolution, yet specificity remains unchanged. The purpose of this study was to determine whether the low-flow color duplex technique alters the specificity of B-mode ultrasonography. PATIENTS AND METHODS: Forty-one patients with tumors of the parotid gland were examined by color duplex echography as well as histologically. Twenty-eight of the 41 patients had benign tumors and 13 had malignant disease. In 17 of 41 patients, color duplex ultrasonography failed to detect any vascularization within the tumor. Histopathological examination showed that 3 of these 17 tumors were malignant and 14 of 17 were benign. Intranodal vascularization was detected in 24 cases. Ten of these patients were found to have malignant tumors of the parotid gland; 14 had benign parotid tumors. RESULTS: Our present findings show that marked intratumoral vascularization especially appears in malignant tumors. In contrast to lymph nodes, the location and texture of intranodal blood vessels do not provide information about the nature of the neoplasm. CONCLUSIONS: Low flow duplex ultrasonography does not increase the specificity of preoperative examination in tumors of the parotid gland.  相似文献   
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BACKGROUND: The purpose was to study activation markers of the eosinophil granulocytes in seasonal allergic rhinitis, and the impact of topical steroid therapy thereupon. METHODS: Sixty-three rhinitis patients with monoallergy to grass were examined before and at peak pollen season. Blood eosinophil count, eosinophil cationic protein (ECP), and eosinophil peroxidase (EPO) in serum and nasal lavage fluid were measured. During the season, patients were randomized to treatment with intranasal fluticasone propionate 0.1 mg o.d. (n=26), 0.2 mg o.d. (n=25), or placebo (n=12). Six healthy persons served as controls. RESULTS: During the season, all parameters, except nasal lavage ECP, increased in the placebo group (P<0.001-P<0.05). Significant differences were seen between the steroid groups and the placebo group for all parameters (P<0.001-P<0.05). Higher eosinophil count (P<0.05), serum EPO (P<0.02), and nasal lavage EPO (P<0.05) were found in patients before season than in controls. The following winter, 44 patients returned for repeated measurement. Lower levels of nasal lavage EPO were observed for patients than levels at the beginning of the season (P<0.0001). CONCLUSIONS: Intranasal fluticasone propionate reduced inflammation of the nasal mucosa, demonstrated locally by nasal lavage ECP and EPO, and systemically by blood eosinophils, serum ECP, and serum EPO. EPO seemed more sensitive than ECP as indicator of allergic inflammation. EPO demonstrated some perennial eosinophil activity in hay fever patients, increasing locally during spring.  相似文献   
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It is not clear what therapeutic application is most likely for agents blocking glycine site of the NMDA receptors (glycineB). Majority of the studies to date used either glycineB antagonists with doubtful brain penetration or partial agonists. Following systemic administration to rats of our newly developed glycineB antagonists (MRZ 2/570; 2/571 and 2/576) and L-701,324 (MSD) as a reference agent the following behavioural effects were observed: weak (if any) antiparkinsonian-like effects, lack of anxiolytic activity, inhibition of physical and motivational aspects of morphine dependence and neuroprotective activity in global ischaemia. The side effects include: sedation, ataxia, and myorelaxation. We detected neither vacuolisation in the cingulate cortex nor impairment of pre-pulse inhibition indicating lack of psychotomimetic potential.  相似文献   
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