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61.
62.
Fahim C Stip E Mancini-Marïe A Mensour B Boulay LJ Leroux JM Beaudoin G Bourgouin P Beauregard M 《Psychiatry research》2005,140(1):1-15
The aim of this functional magnetic resonance imaging (fMRI) study was to compare regional brain activity in schizophrenia subjects with (FA+) and without (FA-) flat affect during the viewing of emotionally negative pictures. Thirteen FA+ subjects and 11 FA- subjects were scanned while being presented with a series of emotionally negative and neutral pictures. Experientially, the viewing of the negative pictures induced a negative emotional state whose intensity was significantly greater in the FA- group than in the FA+ group. Neurally, the Negative minus Neutral contrast revealed, in the FA- group, significant loci of activation in the midbrain, pons, anterior cingulate cortex, insula, ventrolateral orbitofrontal cortex, anterior temporal pole, amygdala, medial prefrontal cortex, and extrastriate visual cortex. In the FA+ group, this contrast produced significant loci of activation in the midbrain, pons, anterior temporal pole, and extrastriate visual cortex. When the brain activity measured in the FA+ group was subtracted from that measured in the FA- group, only the lingual gyrus was significantly activated. Perhaps in FA+ subjects an amygdaloid malfunction rendered the amygdala unable to correctly evaluate the emotional meaning of the pictures presented, thus preventing effective connectivity linking the amygdala to the brain regions implicated in the physiological and experiential dimensions of emotion. Alternatively, a disturbance of effective connectivity in the neural networks linking the midbrain and the medial prefrontal system may have been responsible for the quasi absence of emotional reaction in FA+ subjects, and the abnormal functioning of the medial prefrontal cortex and anterior cingulate cortex in the FA+ group. 相似文献
63.
64.
Surgeon-performed ultrasound in the ICU setting 总被引:3,自引:0,他引:3
Evaluation of critically ill patients is often challenging due to altered sensorium, underlying disease, and the presence of multiple drains or monitoring devices. In such circumstances, the ability of physicians to perform ultrasound examinations in the intensive care unit provides a useful diagnostic and therapeutic adjunct. In this article,we review the application of surgeon-performed ultrasonography in the evaluation and management of critically ill patients. 相似文献
65.
Secondary ultrasound examination increases the sensitivity of the FAST exam in blunt trauma 总被引:3,自引:0,他引:3
Blackbourne LH Soffer D McKenney M Amortegui J Schulman CI Crookes B Habib F Benjamin R Lopez PP Namias N Lynn M Cohn SM 《The Journal of trauma》2004,57(5):934-938
INTRODUCTION: Approximately one third of stable patients with significant intra-abdominal injury do not have significant intraperitoneal blood evident on admission. We hypothesized that a delayed, repeat ultrasound study (Secondary Ultrasound--SUS) will reveal additional intra-abdominal injuries and hemoperitoneum. METHODS: We performed a prospective observational study of trauma patients at our Level I trauma center from April 2003 to December 2003. Patients underwent an initial ultrasound (US), followed by a SUS examination within 24 hours of admission. Patients not eligible for a SUS because of early discharge, operative intervention or death were excluded. All US and SUS exams were performed and evaluated by surgical/emergency medicine house staff or surgical attendings. RESULTS: Five hundred forty-seven patients had both an initial US and a SUS examination. The sensitivity of the initial US in this patient population was 31.1% and increased to 72.1% on SUS (p < 0.001) for intra-abdominal injury or intra-abdominal fluid. The specificity for the initial US was 99.8% and 99.8% for SUS. The negative predictive value was 92.0% for the initial US and increased to 96.6% for SUS (p = 0.002). The accuracy of the initial ultrasound was 92.1% and increased to 96.7% on the SUS (p < 0.002). No patient with a negative SUS after 4 hours developed clinically significant hemoperitoneum. CONCLUSION: A secondary ultrasound of the abdomen significantly increases the sensitivity of ultrasound to detect intra-abdominal injury. 相似文献
66.
Pervez A Zaman F Aslam A Petty S Murphy S Vachharajani T Abreo K;American Society of Diagnostic Interventional Nephrology 《Seminars in dialysis》2004,17(1):61-64
We retrospectively reviewed all subcutaneous single- and double-lumen port catheters (PCs) inserted by interventional nephrologists at our institution to determine the success rate, immediate and late complications, and functional life. From January 2000 to August 2002, 187 PCs were placed in 187 patients (42% males, 51% Caucasians, mean age 50 +/- 14 years). There were no immediate complications related to the procedure such as hemorrhage, pulmonary embolism, or pneumothorax. There were a total of 35,078 catheter-days of follow-up. Sixteen catheters were removed during the observation period: three because of infection, seven after completion of chemotherapy, and six for other reasons. The remaining PCs are either functioning or the patients have died. The initial success rate was 100%. Kaplan-Meier analysis showed a 30-day survival of 97% and a 1-year survival of 92%. Interventional nephrologists, who have adequate training in central venous tunneled cuffed catheter placements, can successfully place PCs, with excellent success and minimal complications. 相似文献
67.
Carey J Fahim A Munro M 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,70(1):73-81
Cardiovascular catheterization is a common medical procedure. A single braided catheter with different rigidities at the proximal and distal ends can, if properly designed, provide the necessary control and flexibility and thus replace the current two-piece (external catheter/internal guidewire) system. An analytical model based on classical laminate plate theory was developed in order to predict the elastic properties of angle-plied, single-overlap two-dimensional fiber composite tubular braids, which are required for the determination of the axial, flexural, and torsional rigidities. In this work the analytical model has been used to design one-piece cardiovascular catheters with axial, flexural, and torsional rigidities similar to those values for existing two-piece catheters, thus validating the model as a tool for designing braided cardiovascular catheters. 相似文献
68.
Because of the potential importance of the lactational amenorrhea method (LAM) as a family-planning option in Egypt, we analyzed data from the 1995 Egyptian Demographic and Health Survey (EDHS) to study breastfeeding practices, use of contraception, reproductive history and sociodemographic factors for 5504 mothers with children under 3 years. According to the EDHS data, about 80% of Egyptian women breastfed for at least 6 months, and 40% breastfed for 15-18 months. Over half of breastfeeding mothers used no additional contraception. Thirty-six percent of mothers breastfeeding children younger than 6 months who reported using no additional contraception were exclusively breastfeeding and amenorrheic, but only 4% reported relying on breastfeeding for family planning. We also held eight focus group discussions with breastfeeding mothers from urban and rural Upper and Lower Egypt on their use of contraceptive methods, breastfeeding, lactational amenorrhea and LAM. Participants showed strong recognition of the contraceptive effects of breastfeeding but differed widely in their understanding of lactational infecundability and knowledge of LAM as a method. These results suggest that LAM would be widely acceptable to Egyptian women, but that an educational program about the method is needed. 相似文献
69.
Haji SA Brocks DC Fahim MM Asbell PA 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2004,20(4):329-336
PURPOSE: We used EyeSys videokeratography to evaluate corneal shape changes induced by conductive keratoplasty, a procedure that utilizes radio frequency energy to alter corneal shape to correct hyperopia. METHODS: Follow-up data were available for 19 eyes (out of 24 eyes of 13 patients). Preoperative spherical hyperopia ranged from +0.75 to +3.25 D with astigmatism <0.75 D. Manifest refractive spherical equivalent refraction (MRSE), uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical parameter predicted corneal acuity (PCA), corneal uniformity index (CU Index), regular astigmatism, total astigmatism, average simulated keratometry (Avg Sim K), effective refractive power, and asphericity were measured preoperatively and at 6 and 12 months postoperatively. RESULTS: Twelve months postoperatively, mean PCA, CU Index, and BSCVA were maintained at preoperative levels. Mean UCVA (LogMAR) improved from 0.53+/-0.21 to 0.10+/-0.19 (P<.05) with a mean MRSE change from +1.62+/-0.76 D to -0.06+/-0.84 D (P<.05) from preoperative to 12 months postoperative. Mean asphericity increased +0.044+/-0.24 D (P>.05), mean Avg Sim K increased 1.88+/-0.72 D (P<.05), mean effective refractive power increased 1.71+/-0.79 D (P<.05), mean cylinder (cycloplegic refraction) increased 0.19+/-0.36 D (P<.05), mean regular astigmatism increased 0.25+/-0.49 D (P>.05), and mean irregular astigmatism decreased 0.01+/-0.13 D (P>.05) from preoperative to 12 months after conductive keratoplasty. CONCLUSIONS: Avg Sim K and effective refractive power changes support the refractive results; 12-month postoperative maintenance of BSCVA, PCA, and CU Index suggest the procedure is safe. Conductive keratoplasty induced a slight regular astigmatism in some eyes, which decreased with time. The increase in mean corneal asphericity indicated possible induction of central and peripheral cornea changes. 相似文献
70.
Tiplaxtinin, a novel, orally efficacious inhibitor of plasminogen activator inhibitor-1: design, synthesis, and preclinical characterization 总被引:7,自引:0,他引:7
Elokdah H Abou-Gharbia M Hennan JK McFarlane G Mugford CP Krishnamurthy G Crandall DL 《Journal of medicinal chemistry》2004,47(14):3491-3494
Indole oxoacetic acid derivatives were prepared and evaluated for in vitro binding to and inactivation of human plasminogen activator inhibitor-1 (PAI-1). SAR based on biochemical, physiological, and pharmacokinetic attributes led to identification of tiplaxtinin as the optimal selective PAI-1 inhibitor. Tiplaxtinin exhibited in vivo oral efficacy in two different models of acute arterial thrombosis. The remarkable preclinical safety and metabolic stability profiles of tiplaxtinin led to advancing the compound to clinical trials. 相似文献