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71.
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Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
73.
P L Wyffels J R DeBord J S Marshall G Thors W H Marshall 《Journal of vascular surgery》1992,15(5):771-8; discussion 778-9
Over a 30-month period (May 1988 to November 1990) 143 acutely ischemic lower extremities (126 patients) were treated with an aggressive surgical approach that included ankle level tibial-peroneal artery thromboembolectomy. Twelve lower extremities in 10 patients that remained ischemic were further treated with adjuvant ankle level urokinase infusion. Sixteen ankle level arteries in 12 extremities were infused with an intraoperative bolus (1 to 2) of urokinase (50,000 to 100,000 units). Continuous postoperative urokinase (25,000 to 50,000 units per catheter per hour x 1 to 5 days) was infused through ankle level arteriotomies in 10 extremities (14 arteries) that did not improve with the initial intraoperative bolus. Concomitant bypass grafting was necessary in four extremities. With adequate inflow established, adjuvant ankle level urokinase salvaged all 12 extremities. The mean increase in ankle/brachial pressure index was 0.84. During continuous postoperative urokinase infusion, lower extremity bleeding requiring blood transfusion occurred in four patients (50%). No deaths occurred in the operative period. Although rhabdomyolysis occurred in 90% of patients, no patients had renal insufficiency. The addition of ankle level urokinase delivery increased the potential limb salvage from 90% of the entire 143 extremities treated during this period to an actual limb salvage of 98%. A mean follow up of 13 months (6 to 36 months) identified one late amputation. Despite the demanding postoperative management required in these patients and the frequent need for early reoperation, the limb salvage obtained justifies this aggressive adjuvant technique in the management of the acutely ischemic lower extremity. 相似文献
74.
Elevated NMDA receptors in parkinsonian striatum. 总被引:3,自引:0,他引:3
Dopamine-glutamate interactions contribute to normal striatal function and have been implicated in neurotoxicity at nigrostriatal dopamine (DA) terminals. The present study examined the striata of idiopathic Parkinson's disease (PD) patients and age-matched controls for regional differences in the DA transporter and binding to N-methyl-D-aspartate (NMDA) receptors. [3H]Mazindol labeling of the DA transporter was reduced by 70-80% in the caudate and putamen of PD patients, with reductions being more extensive dorsally than ventrally. In contrast, L-[3H]glutamate binding to NDMA-sensitive receptors was 20-40% higher in PD cases than in controls. These findings raise the possibility that modifications occur within corticostriatal glutamate synapses of PD patients, possibly as a consequence of reduced nigrostriatal DA activity. 相似文献
75.
P Le Roux B Marshall F Toutain J-F Mary G Pinon E Briquet B Le Luyer 《Archives de pédiatrie》2004,11(8):908-915
Nosocomial infections are a preoccupation in a pediatric hospital mainly during the winter with bronchiolitis and gastroenteritis epidemics. We have examined the risk factors of nosocomial infections. MATERIAL AND METHODS: A prospective study was conducted between November, 1999 and March, 2000 in the infants units of the Le Havre hospital. We systematically listed the admissions and contacted the family after their discharge by phone. A geographic information system was implemented to display the epidemiological data; this software is able to illustrate the sectors at risk. RESULTS: During the study, 687 infants were hospitalized of whom 458 for bronchiolitis and community-acquired gastroenteritis. Mean age was 5.4 months old. No nosocomial bronchiolitis occurred. Prevalence of nosocomial gastroenteritis was 10% (68 cases including nine after discharge). Infants with nosocomial infection were younger than those with community-acquired infection (6.6 months vs. 11.2 months, P < 0.01). The mean length of stay was longer in nosocomial infection (7.7 vs. 4.1 days, P < 0.05). Among the infants with bronchiolitis, 16% have developed nosocomial intestinal infections (RR = 2.65, IC: 1.59-4.4; P < 0.01). The geographic analysis pointed the area with nosocomial risk (bedroom without water, nearness of nurse office and games room). CONCLUSION: Geographic information system is a part of the quality control system and may have some interaction effect on final decision making. Incidence of nosocomial infections showed the need for a prevention strategy in a pediatric hospital. 相似文献
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Shamir Patel Geoffrey B Marshall Robin R Gray 《Journal l'Association canadienne des radiologistes》2004,55(5):288-93; quiz 293
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