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81.
Droste DW Jekentaite R Stypmann J Grude M Hansberg T Ritter M Nabavi D Nam EM Dittrich R Wichter T Ringelstein EB 《Cerebrovascular diseases (Basel, Switzerland)》2002,13(4):235-241
BACKGROUND AND PURPOSE: Cardiac right-to-left shunts (RLS) can be identified by transesophageal echocardiography (TEE) as well as by transcranial Doppler ultrasound (TCD) using contrast agents, such as Echovist-200 or Echovist-300 in conjunction with a Valsalva maneuver (VM) as provocation procedure. Both Echovist preparations are in use. Currently, the appropriate timing of the VM is still under debate. Methods: Sixty-four patients were investigated by both TEE and bilateral TCD of the middle cerebral arteries. The following protocol was applied in a randomized way: (1) no VM, (2) VM for 5 s starting with the beginning of Echovist-300 injection, (3) VM for 5 s starting 5 s after the beginning of Echovist-300 injection, (4) VM for 5 s starting 10 s after the beginning of Echovist-300 injection, and (5) VM for 5 s starting 5 s after the beginning of Echovist-200 injection. Results: In 27 patients, an RLS was demonstrated by both TEE and contrast TCD (shunt-positive). Twenty-two patients were negative in both investigations, no patient was positive on TEE but negative on TCD, 15 patients were only positive on at least one TCD investigation but negative on TEE. Tests 3 and 5 were the most appropriate ones; test 3 was slightly superior to test 5. Conclusions: TCD using Echovist-300 or Echovist-200 is a sensitive method to identify TEE-proven cardiac RLS. To achieve the best diagnostic accuracy, the VM should be performed for a duration of 5 s starting at 5 s following the beginning of contrast injection. 相似文献
82.
83.
Kaufman CS Bachman B Littrup PJ White M Carolin KA Freman-Gibb L Francescatti D Stocks LH Smith JS Henry CA Bailey L Harness JK Simmons R 《American journal of surgery》2002,184(5):394-400
BACKGROUND: Fibroadenomas commonly found by palpation and routine mammography account for approximately 20% of open surgical breast biopsies. Alternatives to open surgery include tumor removal using an automated coring device and tumor ablation using heating or cooling elements. We report our initial experience with cryoablation of biopsy-proven benign fibroadenomas. METHODS: A table-top cryoablation system employing a 2.4-mm cryoprobe was used to treat biopsy-proven benign fibroadenomas up to 4 cm in maximum diameter in a prospective nonrandomized fashion. The cryoprobe was placed under ultrasound guidance. Using a treatment algorithm based on fibroadenoma size, all tumors were subjected to two freeze cycles with an interposing thaw. Skin appearance and temperature, probe temperature, iceball size, and patient comfort were closely monitored during the procedure. Follow-up examinations including ultrasonography and photographs were scheduled for up to 12 months postablation. RESULTS: Fifty patients with 57 core biopsy-proven benign fibroadenomas were treated. Seven early cases were treated in an ambulatory surgery center setting. The remaining procedures were completely office-based using only local anesthetic. Tumor diameter varied from 7 mm to 42 mm (mean 21 mm). The iceball engulfed the target lesion in each case. Transient postoperative side effects were local swelling and ecchymosis. Postoperative discomfort rarely required medication beyond acetaminophen or ibuprofen. Lesions showed progressive shrinkage and disappearance over 3 to 12 months. No skin injury was noted and appearance remained excellent. Patient satisfaction was excellent. CONCLUSIONS: With office-based use of ultrasound-guided cryoablation for fibroadenomas there was little or no pain, target lesions were reduced in size or eliminated, scarring was minimal, cosmesis outstanding, and patient satisfaction was excellent. Cryoablation offers a useful office-based alternative to surgical excision of benign fibroadenomas. 相似文献
84.
NO reduces PMN adhesion to human vascular endothelial cells due to downregulation of ICAM-1 mRNA and surface expression 总被引:8,自引:0,他引:8
Lindemann S Sharafi M Spiecker M Buerke M Fisch A Grosser T Veit K Gierer C Ibe W Meyer J Darius H 《Thrombosis research》2000,97(3):113-123
Reperfusion damage is largely due to the adherence of polymorphonuclear leukocytes to the endothelium initiated by adhesion molecule upregulation. The reduced endothelial nitric oxide release during ischemia may be involved in the upregulation of intercellular adhesion molecule 1. In this study, we tested if nitric oxide donors suppress polymorphonuclear leukocyte adherence to activated endothelial cells by inhibition of the intercellular adhesion molecule 1 surface expression. Confluent human umbilical vein endothelial cells were stimulated with tumor necrosis factor alpha (300 U/mL) after preincubation with increasing concentrations of the nitric oxide donors CAS 1609 (0.005-5 mM/L) and 3-(4-morpholinyl)-sydnonimine (0.01-1 mM/L). Intercellular adhesion molecule 1 surface expression was measured in a cell surface enzyme-linked immunosorbent assay, intercellular adhesion molecule 1 mRNA by Northern analysis. Human saphenous vein endothelial cells were transfected with the inducible nitric oxide synthase gene and stimulated with tumor necrosis factor alpha (300 U/mL). Fluorescein green-labeled polymorphonuclear leukocytes adhering to activated human umbilical vein endothelial cells/human saphenous vein endothelial cells were quantified by epifluorescent microscopy. The intercellular adhesion molecule 1 surface expression of activated human umbilical vein endothelial cells/human saphenous vein endothelial cells was significantly diminished to 40 to 60% of the maximum after treatment with CAS 1609, 3-(4-morpholinyl)-sydnonimine, or transfection with the inducible nitric oxide synthase gene. Intercellular adhesion molecule 1 mRNA was diminished by CAS 1609 and 3-(4-morpholinyl)-sydnonimine in the same manner. The functional relevance of our data was shown by reduction of polymorphonuclear leukocyte adherence to activated human umbilical vein endothelial cells/human saphenous vein endothelial cells following treatment with CAS 1609 and 3-(4-morpholinyl)-sydnonimine or transfection with inducible nitric oxide synthase. Tumor necrosis factor-induced polymorphonuclear leukocyte adherence was abolished by blocking antibody against intercellular adhesion molecule 1. Thus, exogenous or endogenous substitution of nitric oxide diminishes the expression of endothelial intercellular adhesion molecule 1 and its mRNA following tumor necrosis factor alpha stimulation. This results in a reduced polymorphonuclear leukocyte adherence to activated endothelium. 相似文献
85.
Roman Müllenbach Darius Makuch Hans-Joachim Wagner Nikolaus Blin 《International journal of legal medicine》1993,105(6):307-309
Summary The present report describes a novel approach for the identification of human or non-human specimens after long-term storage in a badly preserved state. The application of the PCR-technique (polymerase chain reaction) using human-specific primers as well as Southern blot (filter) hybridization of the sample DNA to a primate-specific DNA probe enabled us to extend the positive identification beyond the limits of conventional methods such as serological or morphological examinations. 相似文献
86.
87.
Physicians' communication with a cancer patient and a relative: a randomized study assessing the efficacy of consolidation workshops 总被引:1,自引:0,他引:1
Delvaux N Merckaert I Marchal S Libert Y Conradt S Boniver J Etienne AM Fontaine O Janne P Klastersky J Mélot C Reynaert C Scalliet P Slachmuylder JL Razavi D 《Cancer》2005,103(11):2397-2411
BACKGROUND: Although patients with cancer are often accompanied by a relative during medical interviews, to the authors' knowledge little is known regarding the efficacy of communication skills training programs on physicians' communication skills in this context. The objective of the current study was to assess the efficacy of 6 consolidation workshops, 3 hours in length, that were conducted after a 2.5-day basic training program. METHODS: After attending the basic training program, physicians were assigned randomly to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual interviews that were recorded on an audio tape at baseline, after consolidation workshops for the consolidation-workshops group, and 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' and relatives' perceptions of and satisfaction with physicians' communication performance were assessed using a 15-item questionnaire. RESULTS: Sixty-two physicians completed the training program. Compared with physicians who participated to the basic training program, when addressing the patient, physicians who were randomized to the consolidation workshops used more open, open directive, and screening questions (P = 0.011 in simulated patient interviews and P = 0.005 in actual patient interviews) and elicited and clarified psychologic concerns more often (P = 0.006 in simulated patient interviews and P < 0.001 in actual patient interviews). When they addressed the relative, physicians who were randomized to the consolidation workshops gave less premature information (P = 0.032 in simulated patient interviews and P < 0.001 in actual patient interviews). When they addressed the patient and the relative simultaneously, physicians who were randomized to the consolidation workshops used more empathy, educated guesses, alerting to reality, confronting, negotiating, and summarizing (P = 0.003 in simulated patient interviews and P = 0.024 in actual patient interviews). Patients, but not relatives, who interacted with physicians in the consolidation-workshops group were more satisfied globally with the interviews (P = 0.022). CONCLUSIONS: Six 3-hour consolidation workshops resulted in improved communication skills addressed to patients and to relatives. The current results showed that the transfer of skills addressing relatives' concerns remained limited and that consolidation workshops should focus even more systematically on the practice of three-person interviews. 相似文献
88.
Merckaert I Libert Y Delvaux N Marchal S Boniver J Etienne AM Klastersky J Reynaert C Scalliet P Slachmuylder JL Razavi D 《Cancer》2005,104(2):411-421
BACKGROUND: No study to date has assessed the impact of skills acquisition after a communication skills training program on physicians' ability to detect distress in patients with cancer. METHODS: First, the authors used a randomized design to assess the impact, on physicians' ability to detect patients' distress, of a 1-hour theoretical information course followed by 2 communication skills training programs: a 2.5-day basic training program and the same training program consolidated by 6 3-hour consolidation workshops. Then, contextual, patient, and communication variables or factors associated with physicians' detection of patients' distress were investigated. After they attended the basic communication skills training program, physicians were assigned randomly to consolidation workshops or to a waiting list. Interviews with a cancer patient were recorded before training, after consolidation workshops for the group that attended consolidation workshops, and approximately 5 months after basic training for the group that attended basic training without the consolidation workshops. Patient distress was recorded with the Hospital Anxiety and Depression Scale before the interviews. Physicians rated their patients' distress on a visual analog scale after the interviews. Physicians' ability to detect patients' distress was measured through computing differences between physicians' ratings of patients' distress and patients' self-reported distress. Communication skills were analyzed according to the Cancer Research Campaign Workshop Evaluation Manual. RESULTS: Fifty-eight physicians were evaluable. Repeated-measures analysis of variance showed no statistically significant changes over time and between groups in physicians' ability to assess patient distress. Mixed-effects modeling showed that physicians' detection of patients' distress was associated negatively with patients' educational level (P = 0.042) and with patients' self-reported distress (P < 0.000). Mixed-effects modeling also showed that physicians' detection of patient distress was associated positively with physicians breaking bad news (P = 0.022) and using assessment skills (P = 0.015) and supportive skills (P = 0.045). CONCLUSIONS: Contrary to what was expected, no change was observed in physicians' ability to detect distress in patients with cancer after a communication skills training programs, regardless of whether physicians attended the basic training program or the basic training program followed by the consolidation workshops. The results indicated a need for further improvements in physicians' detection skills through specific training modules, including theoretical information about factors that interfere with physicians' detection and through role-playing exercises that focus on assessment and supportive skills that facilitate detection. 相似文献
89.
Dickerson RN Mason DL Croce MA Minard G Brown RO 《JPEN. Journal of parenteral and enteral nutrition》2005,29(6):429-435
BACKGROUND: Computer-based simulated biologic neural network models have made significant strides in clinical medicine. METHODS: To determine the predictive performance of a conventional regression model and an artificial neural network for estimating urea nitrogen appearance (UNA) during critical illness, 125 adult patients admitted to the trauma intensive care unit who required specialized nutrition support were studied. The first 100 consecutive patients were used to develop the 2 models. The first model used stepwise multivariate regression analysis. The second model entailed the use of a feeding-forward, back-propagation, supervised neural network. Bias and precision of both methods were evaluated in 25 separate patients. RESULTS: Multivariate regression analysis revealed a significant highly correlative relationship (r(2) = .918, p < or = .01): Predicted UNA (g/d) = (0.29 x WT) + (1.20 x WBC) + (0.44 x SUN) with WT as current body weight in kg, WBC as white blood cell count in cells/mm(3), and SUN as serum urea nitrogen concentration (mg/dL). The regression method was biased toward overestimating measured UNA, whereas the neural network was unbiased. Precision (95% confidence interval) of the neural network was significantly better than the regression (3.3-7.2 g vs 7.3-11.6 g, respectively, p < .01). Regression analysis successfully predicted UNA within 3 g of measured UNA in 16% (4 of 25) of patients, whereas the neural network successfully predicted UNA in 44% (11 out of 25) of patients (p < .06). CONCLUSIONS: These preliminary data indicate that use of an artificial neural network may be superior to conventional regression modeling techniques for estimating UNA in critically ill adult multiple-trauma patients receiving specialized nutrition support. 相似文献
90.
Cook A Salle JL Reid J Chow KF Kuan J Razvi H Farhat WA Bagli DJ Khoury AE 《The Journal of urology》2005,174(5):1958-1960
PURPOSE: Changes in referral patterns and resource allocation into Centers of Excellence affect the educational experience of urology trainees by altering resident exposure to patients and clinicians, especially at sites where subspecialty deficiencies exist. Access to educators at Centers of Excellence using interactive videoconferencing technology may facilitate residency training objectives and enhance trainees' overall educational experience. We prospectively evaluated the implementation of this technology at tertiary care teaching centers to enhance urology resident education. MATERIALS AND METHODS: Using videoconferencing technology, urology residents at the University of Western Ontario (London, Canada) participated in a series of didactic, interactive pediatric urology teleteaching seminars. These were presented by an expert pediatric urologist from the Hospital for Sick Children, Toronto, Canada. Using a 5-point Likert scale (1-strongly disagree, 5-strongly agree), participants responded to statements pertaining to seminar content, technology and ease of use at the completion of each session. The results were subsequently tabulated and evaluated to determine the effectiveness and accessibility of the program in providing expert pediatric urological education to residents at a remote urology training program. RESULTS: The entire urology resident staff from postgraduate year 1 to 5 participated in the seminar program. The overall acceptance of this medium was high (mean score 4.5). The quality of presentation, as well as picture and sound quality, all received mean scores greater than 4. Participants indicated that their ability to interact with the presenter was not inhibited by using this medium. All participants agreed that they would use this technology in the future (mean score 4.5) and that the presentation would not be improved if the presenter were on-site. Due to preexisting technology at both centers, no direct cost was incurred throughout the study. CONCLUSIONS: Our experience suggests that interactive teleteaching using readily available, existing technology, is a cost-effective and accepted method of providing trainees with an appropriate educational experience. In centers where subspecialty deficiencies exist, this medium may provide residents with the necessary education requirements of their respective programs without the need for costly teacher (or student) travel. Continual improvements in technology as well as the addition of multiple sites will increased this medium's impact in the future. 相似文献