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21.
Prosopagnosia is currently viewed within the constraints of two competing theories of face recognition, one highlighting the analysis of features, the other focusing on configural processing of the whole face. This study investigated the role of feature analysis versus whole face configural processing in the recognition of facial expression. A prosopagnosic patient, SC made expression decisions from whole and incomplete (eyes-only and mouth-only) faces where features had been obscured. SC was impaired at recognizing some (e.g., anger, sadness, and fear), but not all (e.g., happiness) emotional expressions from the whole face. Analyses of his performance on incomplete faces indicated that his recognition of some expressions actually improved relative to his performance on the whole face condition. We argue that in SC interference from damaged configural processes seem to override an intact ability to utilize part-based or local feature cues.  相似文献   
22.
The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc.  相似文献   
23.
The presence of noble gas and other short-lived radionuclides in air borne effluents from RBMK-1500-type reactor has been investigated using experimental and theoretical instrumentation for detection purposes. Activity concentrations of (85m)Kr, (87)Kr, (88)Kr, (135m)Xe, (135)Xe, (133)Xe and (41)Ar were measured in air emissions from Ignalina NPP using a special method and special equipment. Theoretical detection of reactor-borne radionuclides and investigation of their behaviour in a nuclear fuel during operation of nuclear reactor was performed using an analytical model based on reactor physics. An innovative method for the estimation of noble gas flow time from the defective nuclear fuel element through the ventilation stack of NPP to the atmosphere based on comparison of the experimentally and theoretically evaluated activity ratios of (88)Kr/(85m)Kr; (135)Xe/(133)Xe has been proposed. The estimated flow time of noble gas provides an excellent possibility to obtain modelling-based information about the qualitative and quantitative content of atmospheric releases from NPP.  相似文献   
24.
We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas are highlighted and discussed.  相似文献   
25.
OBJECTIVE: The purpose of this study was to compare the preparation costs of two common methods used for neonatal red blood cell transfusion aliquots. METHODS: Three months of data from a Level 2 and Level 3 neonatal intensive care unit (NICU) were used to determine the comparative cost for red cell aliquot transfusions using an eight bag aliquot/transfer system or the syringe set system. Using leuko-poor red blood cell blood collected in Adsol and containing approximately 320 ml of red blood cells and supernatant solution, the average cost of neonatal transfusion aliquots was determined using the Charter Medical syringe set and the Charter Medical eight bag aliquot/transfer system. RESULTS: A total of 126 red blood cell transfusion aliquots were used over the three month period. The amount transfused with each aliquot ranged from 5.0 ml - 55.0 ml with an average of 24.0 ml per aliquot. The cost per aliquot using the eight aliquot/transfer set was calculated as $36.25 and the cost per aliquot using the syringe set cost was calculated as $30.71. Additional benefits observed with the syringe set included decreased blood waste. CONCLUSION: When comparing Charter Medical multiple aliquot bag sets and the Charter Medical syringe aliquot system to provide neonatal transfusions, the use of the syringe system decreased blood waste and proved more cost effective.  相似文献   
26.
Binding of [3H]Ro 5-4864 to mitochondrial membrane preparations of rat cerebral cortex was measured after repeated (5 days) IV administration of diazepam (10 mg/kg daily) and clonazepam (2.5 mg/kg daily). The B(max) value for [3H]Ro 5-4864 was significantly reduced in rats treated with diazepam (-49%) but not in those treated with clonazepam. These findings suggest the involvement of peripheral-type binding sites in the development of rapid tolerance to the sedative effects of benzodiazepines. A downregulation of [3H]Ro 5-4864 (-65%) was also observed after repeated administration of Ro 5-4864 (4 mg/kg daily), thus confirming that this compound behaves as an agonist at its own recognition sites.  相似文献   
27.
Abstract: Between 1970 and 1990, 1,008 patients with early-stage breast cancer were treated by conservative surgery without axillary dissection followed by radiation therapy to the intact breast in the Department of Therapeutic Radiology at Yale-New Haven Hospital. The patient population, broken down by histologic subtype, was as follows: 761 patients presented with infiltrating ductal carcinoma, 70 patients with pure intraductal, 38 intraductal with focal invasion, 54 infiltrating lobular, 21 tubular, 17 medullary, 16 mucinous, and 29 with other various histologic subtypes. Patients were followed on a regular basis by the referring physicians and radiation oncologists. Diagnostic studies for distant metastases were performed as clinically indicated. Annual mammography was a routine component of the follow-up program. As of 3/96, with a median follow-up of 10.5 years, 83 patients developed an ipsilateral breast tumor recurrence, and 109 patients developed distant metastases resulting in an overall 10-year breast recurrence-free rate of 84%, and a 10-year distant metastasis-free rate of 78%. There were significant differences in clinical stage, pathological nodal involvement, and administration of systemic therapy between various histologic subtypes. As expected, those patients with histologies of low metastatic potential (such as intraductal, tubular, and mucinous) had significantly superior distant recurrence-free survival rates. With respect to breast relapse rates, there were no statistically significant differences in the 5- and 10-year breast recurrence-free rates between any of the histologic subtypes. Patients with intraductal carcinoma with or without focal invasion had similar breast relapse rates as those with other histologic subtypes. Patients with lobular carcinoma in situ as a histologic component also had a similar overall breast relapse-free recurrence rate. In conclusion, long-term follow-up of conservatively treated breast cancer patients demonstrates no significant differences in ipsilateral breast tumor recurrence rates between various histologic subtypes. There are no histologies which had a statistically significantly higher breast-relapse rate than infiltrating ductal carcinomas and therefore no primary histologic subtype represents a relative contraindication to breast conservation therapy.  相似文献   
28.
29.
Corneal abrasion is the most common ocular injury occurring in the perioperative period. Corneal abrasion may occur during general anesthesia, monitored anesthesia care, regional anesthesia, or in the immediate recovery period. This injury is not usually apparent until the patient is in the PACU, and the perianesthesia nurse may be the first clinician to detect this complication. Preventive measures and vigilant care can help reduce the incidence of corneal abrasion in susceptible patients. Early detection and prompt intervention may help reduce the incidence of ocular morbidity. The purpose of this article is to explore the incidence, mechanism of injury, prevention, recognition, and treatment of perioperative corneal abrasion.  相似文献   
30.
The National Collegiate Athletic Association (NCAA) mandates the use of brightly colored, intraoral mouth- guards by football players to reduce the frequency and severity of craniofacial and intraoral morbidity and mortality, and to enhance the ability of officials to observe player compliance. The purpose of this 12-question mail survey was to determine the attitudes of on-Held game officials regarding current NCAA mouthguard regulations and patterns of utilization by college football players. The sample consisted of all 50 Big East Football Conference officials; a response rate of 100 percent was achieved. Only 42 percent of the officials reported observing all players in compliance, and quarterbacks were identified by others as the least compliant group (52%). The majority (88%) indicated that the 1990 rule for brightly colored mouthguards had been beneficial to them in determining player compliance, and 52 percent reported that this rule had resulted in more frequent use by these athletes. Nearly all officials (96%) indicated that they would issue a warning for noncompliance to the player or coach, rather than charging a timeout for a violation as prescribed by NCAA regulations. The majority (70%) believe current enforcement is appropriate, but expressed the opinion that coaches should be held more accountable for player compliance.  相似文献   
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