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91.
K P Stanley R B Fraser M Milner C Bruce 《British journal of obstetrics and gynaecology》1992,99(6):512-515
OBJECTIVE: To assess the distribution of cord blood insulin in an unselected population, and examine its relation to birthweight centiles. SETTING: District General Hospital in Nottinghamshire. SUBJECTS: 209 unselected singleton births. MEAN OUTCOME MEASURE: Cord blood insulin; cord blood C-peptide; birthweight centiles. RESULTS: Hyperinsulinaemic babies (greater than 97th centile for cord insulin) were found at all birthweight centiles. 15% of high birthweight babies were hyperinsulinaemic. For low birthweight babies, the distribution of cord insulin/C-peptide was skewed indicating a high number of low values. Hypoinsulinaemic babies were present up to the 50th centile for birthweight. CONCLUSIONS: Abnormalities of fetal insulinisation may be found in babies of all birthweights. 相似文献
92.
S Falcone R M Quencer B Bowen J H Bruce T P Naidich 《AJNR. American journal of neuroradiology》1992,13(1):403-406
The authors present two biopsy-proved cases of Creutzfeldt-Jakob disease. MR appears to be more sensitive than CT in detecting pathologic changes; signal abnormalities, when found, are predominantly within gray matter and may involve only peripheral cortex. 相似文献
93.
Bruce E. Lewis Colin Sumida Ming H. Hwang Henry S. Loeb 《Catheterization and cardiovascular interventions》1992,26(4):295-299
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc. 相似文献
94.
Jeffrey S. Berns Howard A. Pearson Karen M. Gaudio Bruce McDonald Leonard Krassner Frederic Anderson Dennis Durante Norman J. Siegel 《Pediatric nephrology (Berlin, Germany)》1988,2(2):244-246
Children with the idiopathic nephrotic syndrome (NS) are known to be susceptible to bacterial infections. A recent report suggested that splenic hypofunction may be responsible for this immunological defect. We assessed splenic function by counting the circulating pocked red blood cells (PkRBCs) using interference phase contrast microscopy. PkRBCs are removed by the spleen, so that normal eusplenic individuals have less than 2% PkRBCs while asplenics have 15%–30%. Intermediate values are seen in hyposplenism. Thirty-three measurements of PkRBCs were made in 19 children with NS (mean age 7.5±0.8 years). PkRBCs were normal in all children tested (range 0–0.8%), including two patients with bacterial peritonitis associated with relapse. Thus we were unable to find evidence of hyposplenism in children with NS. 相似文献
95.
96.
Acute selective serotonin reuptake inhibitors increase conditioned fear expression: blockade with a 5-HT(2C) receptor antagonist. 总被引:3,自引:0,他引:3
Nesha S Burghardt David E A Bush Bruce S McEwen Joseph E LeDoux 《Neuropsychopharmacology》2007,62(10):1111-1118
BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) effectively treat various anxiety disorders, although symptoms of anxiety are often exacerbated during early stages of treatment. We previously reported that acute treatment with the SSRI citalopram enhances the acquisition of auditory fear conditioning, which is consistent with the initial anxiogenic effects reported clinically. Here, we extend our findings by assessing the effects of acute SSRI treatment on the expression of previously acquired conditioned fear. METHODS: Rats underwent fear conditioning drug-free. Tone-evoked fear responses were tested after drug treatment the following day. This protocol more closely resembles the clinical setting than pre-conditioning treatment, because it evaluates effects of treatment on a pre-existing fear rather than on the formation of a new fear memory. RESULTS: A single pre-testing injection of the SSRIs citalopram or fluoxetine significantly increased fear expression. There was no effect of the antidepressant tianeptine or the norepinephrine reuptake inhibitor tomoxetine, indicating that this effect is specific to SSRIs. The SSRI-induced enhancement in fear expression was not blocked by tropisetron, a 5-HT(3) receptor antagonist, but was blocked by SB 242084, a specific 5-HT(2C) receptor antagonist. CONCLUSIONS: Enhanced activation of 5-HT(2C) receptors might be a mechanism for the anxiogenic effects of SSRIs observed initially during treatment. 相似文献
97.
98.
Norberto Adame Jr. MD Bruce T. Horwood MD Daniel Caruso MD Ted Wallace MD Louis Velasco MD 《Academic emergency medicine》2006,13(1):114-116
Objectives: To determine whether the Mac‐technique test can detect kinking of the chest tube upon thoracostomy tube placement. Methods: This was a prospective observational study that was conducted October 2000 through October 2001 in an urban Level 1 trauma center. There were 103 consecutive nonrandomized adult trauma patients who required immediate tube thoracostomy during their initial resuscitation who were entered into the study. The Mac‐technique test was performed during standard tube thoracostomy insertion to the appropriate depth. The test involved grasping the external portion of the thoracostomy tube, turning it clockwise 180°, and then releasing the tube. If the tube spontaneously spun back to its original position, the test was considered positive, and the tube was considered kinked. If the tube did not spontaneously spin back and stayed in position upon release, the test was considered negative. Regardless of the results of this test, the tube was secured, and a postprocedure chest radiograph was obtained. The criterion standard for determining a kinked chest tube was its appearance on this chest radiograph. Results: A total of 103 chest tubes were placed by using the Mac‐technique test. The test was positive in eight placements; four tubes were kinked on chest radiograph. The Mac‐technique test was negative in 95 placements; four tubes were kinked on chest radiograph. The Mac technique had a sensitivity of 50% (95% confidence interval [CI] = 15.7% to 84.3%), a specificity of 95.8% (95% CI = 89.6% to 98.8%), a positive likelihood ratio of 11.9, a negative likelihood ratio of 0.52, and an odds ratio using Yates correction of 20.3 (95% CI = 4.1 to 102.1). Conclusions: On the basis of this study, a positive Mac‐technique test is useful to detect chest tubes that are likely to be kinked after insertion and before securing. 相似文献
99.
Kristin Fraser Adam Peets Ian Walker Janet Tworek Michael Paget Bruce Wright & Kevin McLaughlin 《Medical education》2009,43(8):784-789
Context Prior research has demonstrated that residents have poor clinical skills in cardiology and respirology. It is not clear how these skills can be improved because the number of patients with suitable clinical findings whose cooperation might help residents to better develop these clinical skills is limited.
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
100.