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991.
992.
993.
The kinetics of inhaled methyl ethyl ketone (MEK) at a concentration of 200 ppm for four hours were studied in volunteers after swallowing ethanol at a dose of 0.8 g/kg. Ethanol was given either before or at the end of the exposure to MEK. The blood concentrations of MEK, 2-butanol, and 2,3-butanediol were monitored during and after the exposure. MEK concentrations in exhaled air and MEK and 2,3-butanediol concentrations in urine were also measured. Ethanol inhibited the primary oxidative metabolism of MEK and caused an increase in the blood concentrations of MEK and 2-butanol after ingestion. Ethanol ingestion, through higher blood MEK concentrations, also increased the elimination of MEK in the urine and exhaled air. Ethanol taken before exposure to MEK reduced the serum concentration of 2,3-butanediol initially but there was an increase about eight hours after the exposure. Urinary excretion of 2,3-butanediol followed the same pattern. Prior ingestion of ethanol thus seemed to interfere with the metabolism of 2,3-butanediol during and after exposure to MEK. 相似文献
994.
Correlation between penile angiography and duplex scanning of cavernous arteries in impotent men 总被引:1,自引:0,他引:1
During the diagnostic evaluation of patients with vasculogenic impotence duplex scanning has been proposed as a reliable noninvasive method to evaluate the cavernous arteries. However, the sensitivity and specificity of this test have never been elucidated. To provide insight into the clinical value of this test 25 men who presented with impotence and failed to respond to 60 mg. intracavernous papaverine were evaluated with duplex scanning and the results of this modality were compared to penile angiography. The cavernous arteries were considered normal by duplex scanning if the artery demonstrated either a 60% or greater increase in diameter and/or a peak flow velocity of greater than 25 cm. per second 5 minutes after papaverine injection. Penile angiography was considered normal if both cavernous arteries were visualized and appeared to be normal radiographically (after intracorporeal papaverine). In the 25 patients studied there was no significant difference in peak flow velocity between patients with normal or abnormal cavernous arteries by angiography. In addition, arterial dilatation (more than 60%) after papaverine injection did not correlate with the results of the angiogram. These data demonstrate that duplex scanning of the cavernous arteries does not correlate well with what is observed by penile angiography in a selected population of men with vasculogenic erectile dysfunction. Since penile angiography itself has limitations in the evaluation of the penile arteries, the reliability of duplex scanning to identify cavernous artery dysfunction needs additional confirmation. 相似文献
995.
Indications for relaparotomy 总被引:2,自引:0,他引:2
D I Krivitski? V A Shuliarenko I A Babin 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1990,(1):18-21
From 1980 to 1987, 10,446 patients were operated on. In 152 patients, the necessity of a repeated operative intervention arose. In 106 patients the emergency, in 42--delayed, and in 4--elective relaparotomies were performed. There were the following indications for relaparotomy: diffuse and circumscribed peritonitis (78 patients), ileus (46), eventration (11), hemorrhage (12), others (5). Diagnosis of postoperative complications requiring relaparotomy is difficult. The postoperative lethality was 26%. 相似文献
996.
K.M. SIVANANDAIAH V.V. SURESHBABU S.C. SHANKARAMMA 《Chemical biology & drug design》1995,45(4):377-379
Deprotection of the tert-butoxycarbonyl group during solid-phase synthesis of peptides can be conveniently and efficiently carried out using a neutral reagent, silicon tetrachloride/sodium iodide (iodotrichlorosilane). This simple and rapid method has been advantageously employed during the solid-phase synthesis of the pituitary hormone, oxytocin. 相似文献
997.
A Ia Shabalin I Kh Rabkin V I Posudnevski? S M Minkina 《Grudnaia i serdechno-sosudistaia khirurgiia / Ministerstvo zdravookhraneniia SSSR [i] Vsesoiuznoe nauchnoe obshchestvo khirurgov》1990,(6):23-27
The article deals with the experience in surgical treatment of 157 patients with vasorenal hypertension consequent upon unspecific aortoarteritis. On the grounds of communications in the literature and their own clinical findings, the authors analyse the character of the affection in unspecific aortoarteritis and the peculiarities of the course of vasorenal hypertension and emphasize the malignancy of its course and inefficacy of nonoperative treatment. The indications and contraindications for various reconstructive operations on the renal arteries and the dependence of the results of surgery on the duration of the disease and the term of the operative intervention are discussed in detail. The authors also describe their experience in the modern methods of kidney revascularization. With the use of radiologically guided endovascular dilatation and an nitinol endoprosthesis they not only expanded considerably the possibilities of intervention on the renal vessels but improved the results of the management of vasorenal hypertension. 相似文献
998.
N. K. Venkataramana V. R. S. Kolluri K. S. Narayana Swamy V. K. Jain B. S. Das S. Das 《Acta neurochirurgica》1990,107(1-2):44-46
Intradural extramedullary glial tumours of the spinal cord are rare. We report for such tumours arising from the dorsal cord. Myelography and operative findings were almost similar to that of an intradural neurofibroma. Surgical removal had resulted in rewarding neurological recovery. One of them had a recurrence after six years and was re-explored. Anterolateral attachment near the root entry zone suggests its origin probably from the spinal cord with an exophytic growth. 相似文献
999.
There are very few reported cases of milk of calcium in the ureter. Its presence in the ureter is quite unusual and is the
subject of the present report. 相似文献
1000.