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M H Miller W S Tucker J M Bilbao 《Journal l'Association canadienne des radiologistes》1986,37(1):35-37
Multiple vascular lesions in the brain were identified by angiography in a 45-year-old woman with Von Hippel Lindau disease. One of these lesions was a histologically-proven hemangioblastoma. The occurrence of such lesions in a cerebral hemisphere is exceedingly rare and is usually related to Von Hippel Lindau disease. 相似文献
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Werner E Bischoff Brian K Tucker Michelle L Wallis Beth A Reboussin Michael A Pfaller Frederick G Hayden Robert J Sherertz 《Infection control and hospital epidemiology》2007,28(10):1148-1154
OBJECTIVE: Transmission of Staphylococcus aureus via air may play an important role in healthcare settings. This study investigates the impact of barrier precautions on the spread of airborne S. aureus by volunteers with experimentally induced rhinovirus infection (ie, the common cold). DESIGN: Prospective nonrandomized study. SETTING: Wake Forest University School of Medicine (Winston-Salem, NC).Participants. A convenience sample of 10 individuals with nasal S. aureus carriage selected from 593 students screened for carriage. INTERVENTION: Airborne S. aureus dispersal was studied in the 10 participants under the following clothing conditions: street clothes, surgical scrubs, surgical scrubs and a gown, and the latter plus a face mask. After a 4-day baseline period, volunteers were exposed to a rhinovirus, and their clinical course was followed for 12 days. Daily swabs of nasal specimens, pharynx specimens, and skin specimens were obtained for quantitative culture, and cold symptoms were documented. Data were analyzed by random-effects negative binomial models. RESULTS: All participants developed a common cold. Incidence rate ratios (IRRs) indicated that, compared with airborne levels of S. aureus during sessions in which street clothes were worn, airborne levels decreased by 75% when surgical scrubs were worn (P<.001), by 80% when scrubs and a surgical gown were worn (P<.001), and by 82% when scrubs, a gown, and a face mask were worn (P<.001). The addition of a mask to the surgical scrubs and gown did not reduce the airborne dispersal significantly (IRR, 0.92; P>.05). Male volunteers shed twice as much S. aureus as females (incidence rate ratio, 2.04; P=.013). The cold did not alter the efficacy of the barrier precautions. CONCLUSIONS: Scrubs reduced the spread of airborne S. aureus, independent of the presence of a rhinovirus-induced cold. Airborne dispersal of S. aureus during sessions in which participants wore surgical scrubs was not significantly different from that during sessions in which gowns and gowns plus masks were also worn. 相似文献
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L D Holinger M S Volk G F Tucker 《The Annals of otology, rhinology, and laryngology》1987,96(5):505-508
Forty-eight cases of tracheal agenesis have been reported to date. Previous authors have studied gross postmortem laryngeal specimens. Of 37 cases wherein laryngeal findings were mentioned, only 14 were reported to be abnormal. This report details two more cases of tracheal agenesis and includes a detailed histopathologic study of the laryngeal anomalies by serial horizontal section. Although one of these specimens appeared normal at autopsy, both were found to have several abnormalities when studied microscopically in horizontal section. Both have an elliptical cricoid cartilage, an abnormality originally discovered by one of us (G.F.T.) using the same technique. 相似文献
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Rat kidneys were isolated and perfused with a cell-free perfusion buffer containing 4% albumin. Infusion of platelet activating factor (s-PAF) into the isolated perfused kidney caused a dose-dependent fall in renal vascular resistance (RVR): 12 +/- 6% at 10 nM s-PAF, 18 +/- 3% at 100 nM s-PAF and 20 +/- 7% at 1 microM s-PAF. Glomerular filtration rate fell by 32 +/- 5% at 10 nM, 38 +/- 6% at 100 nM, and 52 +/- 10% at 1 microM. s-PAF (50 nM) increased urinary protein excretion after 20 minutes. Because GFR fell to a greater extent than RVR, possible changes in glomerular permeability after s-PAF treatment were assessed morphologically using native ferritin. After s-PAF treatment (100 nM), the number of ferritin particles/micron2 increased from 1.2 +/- 0.9 (control) to 795 +/- 69 in the glomerular basement membrane (GBM) and from 0.2 +/- 0.06 (control) to 98 +/- 29 in lamina rara externa (LRE). To quantitate changes in fixed anionic charges, polyethylenimine (PEI) was quantitated morphologically in GBM. No significant change between s-PAF treated and untreated kidneys was seen. s-PAF did not alter the sialoglycoprotein pattern in the perfused kidney as assessed by lysozyme staining. These results are in contrast to findings with s-PAF in vivo where in addition to increased glomerular permeability, a reduction of fixed anionic charges is seen.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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