Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Q: Abstract: Seventy-five patients, 80-90 years old, each having approximately three associated diseases, underwent a total of 104 gastrointestinal endoscopies. Of these, 73 were upper (29 emergencies) and 31 lower endoscopies (21 were rigid sigmoidoscopies). There were two very mild short-lived complications; vomiting and bleeding. We found 16 gastric ulcers, 16 duodenal or pyloric ulcers, and 11 cases of esophagitis. Bleeding duodenal (8) or gastric (4) ulcers and polyps or malignant tumors (7) were seen less often. In 34 of 68 lesions the endoscopic and x-ray findings were the same. In the other 34 there were 10 endoscopic failures to identify colonic diverticula, hiatus hernia, and gastroesophageal reflux that were seen radiologically. In 24 patients, diagnoses were not made radiologically, but were recognized at endoscopy. The safety and accuracy of endoscopy in the old and sick does not differ from that in younger patients.

A: Aged
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Q: Abstract: Pertussigen is a protein toxin of Bordetella pertussis that acts as a powerful stimulator of the intensity and duration of delayed-type hypersensitivity (DTH) in mice. This study describes the potent in vivo effect of pertussigen on the levels of antigen-specific macrophage-activating lymphokine(s); lymphokine(s) was measured by the stimulation of macrophage procoagulant activity (mPCA), or plasminogen activator (PA) activity. Lymphoid cells were removed from immunized animals and cultured with specific antigen, keyhole limpet hemocyanin, ovalbumin, or human gamma-globulin. The culture supernatants were then incubated with the monocyte-like cell line WEHI-265 to measure mPCA or with WEHI-265 or resident peritoneal macrophages to measure PA activity. Mice were given pertussigen at the time of immunization, and the subsequent generation by lymphocyte supernatants of both of these macrophage activities proved to be greatly enhanced; the effect of pertussigen was antigen specific. Pertussigen thus induces an increase in lymphokine(s) production responsible for the in vitro increase in macrophage mPCA and PA activity and which may be responsible for some of the potent immune effects of this agent in vivo.

A: Animal
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Q: Abstract: We evaluated the role of portasystemic shunts in the hyperkinetic circulatory state in rats with portal hypertension. Cardiac output and regional blood flow were measured by the radioactive microsphere technique in rats with portal hypertension caused by portal vein stenosis, in rats with end-to-side portacaval shunts, and in sham-operated rats. Cardiac output was significantly higher in rats with surgical shunts than in those of the two other groups and was significantly lower in sham-operated rats compared with portal hypertensive rats. Portal tributary blood flow and hepatic arterial blood flow expressed in absolute flow as well as in percentage of cardiac output were significantly increased in rats with surgical shunts compared with other groups. These blood flows were also significantly higher in portal hypertensive rats than in sham-operated animals. A significant correlation was found between cardiac output and portal tributary blood flow in rats with portal vein stenosis and in rats with surgical shunts; this correlation was absent in sham-operated rats. This study shows that the hyperkinetic circulatory state in rats with portal hypertension and a normal liver is related to the presence of portasystemic shunts but not to portal hypertension per se.

A:
Animal
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