During simulated hypokinetics, many biological functions have a tendency to stabilize at different levels with the passing of time. In this experiment, hypokinetic exposure was induced in albino rats by the suspension method for 5 weeks. A new plateau in urinary K+ excretion was attained during the third week, after a transient decrease during the first week. Since the formation of this steady plateau is considered a manifestation of the adaptation of this function, the hypokinetic exposure period was divided into a prestabilized phase and a stabilized phase. To ascertain the biochemical mechanisms of this adaptation process, the effects of aldosterone and anti-aldosterone substances (e.g., tetracycline) on K+ and Na+ excretion patterns in each phase were investigated. Decreasing aldosterone activity in the prestabilized phase and increasing activity in the stabilized phase are recognized as one of the main factors in the renal adaptation process to hypokinetics.

Adaptation, Physiological↗

PubMed1975

[A case of hemangiopericytoma of the stomach (author's transl)].

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Hemangiopericytoma↗

PubMedDate not supplied

Hydroxyl free radical production by the reaction of N-methyl-N'-nitro-N-nitrosoguanidine with hydrogen peroxide without exposure to light.

We examined hydroxyl free radical (.OH) production in the mixture of H2O2 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) without exposure to light using the electron spin resonance spin-trapping technique. When the mixtures were protected from exposure to light, .OH was formed at pH 6.5 and above; it was not formed at pH 5.0 and below, consistent with our previous report. The amount of .OH trapped depended on the concentrations of MNNG and H2O2 and the pH. Nitrite ion was also detected colorimetrically at pH 6.5 and above, but not detected at pH 5.0 and below in the mixtures without exposure to light. Moreover, its production depended on the concentrations of MNNG and H2O2 and the pH. The formation of N-methyl-N'-nitroguanidine in the mixture at pH 7.8 was confirmed by thin-layer chromatography and melting point. These results suggest that nucleophilic attack by H2O2 on the nitroso nitrogen of MNNG results in the formation of N-methyl-N'-nitroguanidine and peroxynitrous acid, which degrades homolytically to yield .OH and nitrogen dioxide, resulting in the production of nitrite ion, at pH 6.5 and above without exposure to light.

Free Radicals↗

PubMedDate not supplied

Whether or not prophylactic excision of the extrahepatic bile duct is appropriate for patients with pancreaticobiliary maljunction without bile duct dilatation.

BACKGROUND/AIMS: The standard treatment for patients with a pancreaticobiliary maljunction (PBM) without bile duct dilatation remains controversial. METHODOLOGY: We followed up 29 patients with such PBM who mainly underwent a cholecystectomy alone. The ages of the patients ranged from 3 to 76 years (average age 47.3 years) and the ratio of males to females was 8 vs. 21. When the diameter of the common bile duct was less than 10mm, such bile ducts were diagnosed to have no dilatation. The main clinical indications for surgery were cholecystolithiasis in 15 patients, choledocholithiasis in 3, cholecystocholedocholithiasis in 2, gallbladder polyp in 2, adenomyomatosis in 2, cholecystitis in 2, and protein plug in 1. RESULTS: The amylase levels of gallbladder bile in 20 patients ranged from 115 to 460,200 IU/mL (a mean of 191,698 IU/mL). One patient died of gastric cancer 182 months after surgery and two patients died of other diseases 153, 171 months after surgeries, respectively. The remaining 26 patients have all been doing well for 36 months to 326 months after surgery (a median follow-up period, 160.5 months). The 10- and 15-year survival rates were 100% and 89.7%. CONCLUSIONS: In conclusion, a prophylactic resection of the extrahepatic bile duct and biliary diversion could be unnecessary for patients with PBM without bile duct dilatation.

Adolescent↗

PubMedDate not supplied

Cytologic demonstration of Entamoeba histolytica using immunoperoxidase techniques. Report of two cases.

An indirect immunoperoxidase technique to detect Entamoeba histolytica in cell samples from patients suspected to have amebiasis is described. Using a rat antiserum specific for E. histolytica, the organism was clearly identified both in smears and in cell blocks. This immunoperoxidase technique seems to offer great possibilities for a specific, accurate and rapid identification of amebic infestation in diagnostic cytology.

Aged↗

PubMedDate not supplied

Immunocytochemical demonstration of carcinoembryonic antigen in cerebrospinal fluid with carcinomatous meningitis from rectal cancer.

The case presented illustrates the application of the immunoperoxidase technique to cerebrospinal fluid (CSF) cytology. The cytologic findings in a Papanicolaou-stained slide of the CSF permitted the diagnosis of a metastatic carcinoma. Positive reactions to carcinoembryonic antigen (CEA) were demonstrated in the tumor cells in the CSF sample as well as in the paraffin-embedded section of the primary rectal cancer. Rising CEA levels were also detected in both CSF and serum. The determination of cancer-associated antigens, such as CEA in the CSF specimen, may be useful in establishing the presence of metastatic tumor in the CSF.

Adult↗