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31.
Since the methods for metronidazole susceptibility testing of Helicobacter pylori have not been standardized or validated, we compared three methods that are used to test the metronidazole susceptibilities of 25 isolates of H. pylori. Specifically, we examined the methods of Steer's replicator agar dilution, tube broth microdilution, and modified Kirby-Bauer disk diffusion. The metronidazole disk zone sizes obtained by the disk diffusion method correlated well (r = 0.74) with the MICs obtained by the agar dilution method. Afterward, the disk diffusion method was used to characterize the metronidazole susceptibilities of 44 isolates of H. pylori. Dual therapy (bismuth and metronidazole) proved to be highly effective against metronidazole-susceptible strains (81.6% eradication rate) but fared poorly against resistant strains (16.7% eradication rate; P < 0.01). Using agar dilution testing, we validated the modified Kirby-Bauer disk diffusion method for metronidazole susceptibility testing of H. pylori and conclude that it is practical, accurate, and clinically applicable.  相似文献   
32.
Growth hormone (GH) secretion declines during normal aging, resulting in lower serum insulin-like growth factor (IGF)-I levels. It has been proposed that many of the catabolic changes seen in normal aging, including osteoporosis and muscle atrophy, are in part caused by the decreased action of the GH-IGF-I axis. In addition, patients with GH deficiency have increased overall cardiovascular mortality. Several investigators have initiated GH treatment for elderly patients with relative hyposomatotropinemia. Initial reports suggest that GH can increase muscle mass, improve exercise tolerance, increase REM sleep and cause an enhanced sense of well-being. The basis for neuropsychiatric changes during GH therapy may be due to a direct CNS action of GH itself, to the increased IGF-I secretion which GH elicits, or to enhanced functioning of peripheral organ systems. Long-term studies will determine whether GH or IGF-I can exert a neurotrophic action in the aging brain.  相似文献   
33.
The pudendal thigh is a sensate fasciocutaneous flap supplied by the posterior labial artery. We report on the results of pudendal thigh flaps used for vaginal reconstruction in eight patients at the time of pelvic exenteration (6) and radical vaginectomy (2). Patients were interviewed and results were assessed 5 to 19 months after surgery. The flaps were raised in the thigh creases just lateral to the hair bearing area of the labia majora and included skin, subcutaneous tissues, deep fascia of the thigh, and the epimysium of the adductor muscles. Flap sizes varied from 9 × 4 cm to 15 × 6 cm. Bilateral flaps were used in seven patients. The flaps were technically easy to perform. Partial (apical) flap necrosis occurred in four patients. One patient developed complete necrosis of bilateral flaps, followed by an enterovaginal fistula. One patient whose flaps did not necrose developed a rectovaginal fistula at the site of rectal reanastomosis. The functional results are disappointing. The only patient having successful vaginal intercourse had a unilateral flap reconstruction following lower vaginectomy in a nonirradiated pelvis. No patient with bilateral flaps or prior pelvic irradiation has had successful coitus. Other long-term sequelae include vulvar pain (2), chronic vaginal discharge (2), hair growth (4), and protrusion of the flaps (2). These vulvovaginal symptoms discourage patients and their partners from genital contact. Breaching the integrity of the vulva to construct a neovagina that is likely to be unsuitable for sexual intercourse may deprive women of their only potential for normal genital sexual responsiveness. Techniques of vaginoplasty require continued assessment.  相似文献   
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The syndrome of inappropriate secretion of arginine vasopressin (AVP) known as the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is associated with a variety of malignant and nonmalignant diseases. Only 17 cases of SIADH have been reported in the literature in association with cancer isolated to the head and neck. A retrospective review of 1,436 patients with head and neck malignancy excluding skin cancer through The University of Iowa Tumor Registry revealed 60 patients with the diagnosis of either SIADH or hyposmolality. A chart review for each of these patients was then done to establish the diagnosis of SIADH through relevant laboratory values and by excluding other causes of hyposmolality and hyponatremia. In 43 of these patients (3%), SIADH was found to be associated only with the cancer of the head and neck. We conclude that the incidence of SIADH in patients with cancer of the head and neck is much higher than previously recognized. As elevated serum AVP levels may not be clinically apparent unless associated with excessive water ingestation, it is possible that an even higher percentage of patients may have increased serum AVP levels.  相似文献   
37.
Sixty-seven patients with advanced carcinoma of the lower female genital tract (cervix, vagina, and vulva) were treated with radiation and concomitant intravenous cisplatin and/or 5-fluorouracil. Fifty-seven patients (85%) responded completely clinically. Thirty-five (61%) complete responders recurred with a median time to recurrence of 6 months. Twenty-six of the thirty-five patients who recurred had some component of local failure. The 22 complete responders who have not recurred have been followed a median of 13 months. Acute toxicity was minimal, with only 6 patients requiring interruption of therapy. Nine (13%) patients developed severe late complications and eight required surgery. The actuarial 5-year survival is 22%. This treatment regimen is disappointing in terms of both survival and local control.  相似文献   
38.
This study was conducted to identify factors that were associated with injuries during 59 varsity high school football games in 1987. For each injury, medical personnel recorded data on the type and body location of each injury, player position, specific player activity at the time of injury, the quarter of the game, the week of the season, playing field conditions, and ambient air temperature. We found injury frequencies, types, body locations and seasonal and game quarter distributions similar to previous reports. This study demonstrated a previously unreported association between playing field condition and injury rate.  相似文献   
39.
The syntheses of a series of 7-(3,5-disubstituted [1,1'-bephenyl]-2-yl)-3,5-dihydroxy-6-heptenoic acids and their lactones are reported. Intrinsic 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitory activity is enhanced markedly when the biphenyl moiety is substituted by chloro or methyl groups at positions 3 and 5 and a fluoro group at position 4'. These substitutions, followed by resolution, provided compounds 100(+) and 110(+) with 2.8 times the intrinsic inhibitory activity of compactin. Compound 100(+) was shown to possess the same chirality in the lactone ring as compactin by single-crystal X-ray crystallography.  相似文献   
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