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81.
Gallium-67 lung uptake: conjugate-view technique 总被引:1,自引:0,他引:1
A conjugate-view technique is derived for calculation of absolute gallium-67 (Ga-67) uptake from scintillation-camera images. The technique combines counts of posterior and anterior images of the lung with an attenuation correction obtained from cobalt-57 (Co-57) transmission imaging. The formulation is such that the effects of Compton scatter build-up are accounted for. Studies utilizing a canine model indicated that, normally, more activity is located in the chest wall than in the lungs. The quantitative technique must therefore accurately account for a variety of Ga-67 distributions, including that in the chest wall. Calculations were performed using a three-component model comparing results obtained with the conjugate-view approach to the actual uptake. These calculations suggest that an assumption of uniform activity distribution allows an accuracy of approximately +/- 10% over a broad range of body-part thicknesses and uptake by the lungs. It was concluded that the conjugate-view technique is necessarily approximate but can provide clinically useful results. 相似文献
82.
Anodic polarization of porous fiber metals 总被引:1,自引:0,他引:1
83.
Background
Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.Methods
Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.Results
The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3rd post-operative day showing lack of activation of platelets in cases of severe bleeding.Conclusion
Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage 相似文献84.
Making errors is part of normal human behaviour. However when errors have significant consequences or occur in high risk industries they become of paramount importance. There has been little research in why and how errors occur in the healthcare industry. Errors occur throughout healthcare, but in particular, surgery as a high risk speciality. Surgery is a dynamic speciality with a milieu of possible mishaps waiting to happen. So to understand and prevent errors in surgery we must explore this intricate multi-cogwheel process. This article will summarise the epidemiology of surgical errors, factors which influence them in the patient pathway, explain concepts and models of why errors occur, technical skill error assessment and possible strategies to prevent or reduce surgical errors. Practicing surgery in the new millennium will embrace new innovations, medications, technologies, equipment, operations, all which aim to improve the treatment and care of patients. However we must remember with this constant evolution in healthcare the error goalposts are forever moving, so we must be vigilant not to take our eye off the error ball. 相似文献
85.
Background: Performing laparoscopic surgery involves a complex cascade of cognitive skills, which may inherently have a constant technical error rate. We assess generic and specific minor and major error rates in laparoscopic cholecystectomies (LCs) performed by consultant surgeons.Methods: Checklists of generic (11) and specific technical minor (six) and major events (eight) were devised for LCs. Two experienced surgeons assessed each full-length operation blindly and independently.Results: A total of 37 LCs were performed by eight consultants. There were no major intraoperative or postoperative complications. Mean inter-rater reliability was κ = 0.91 (range 0.80–0.98) for each of the error categories. Error rates were generic (27/407) 6.6%, minor (59/222) 26.6%, and major (8/296) 2.7%, respectively. There was a significant statistical difference between the minor error group and the other groups, p ≤ 0.05.Conclusions: Performing laparoscopic surgery may always have a background technical error rate. Our present study demonstrates a migration of surgical technical errors in expert laparoscopic surgeons. The surgeons migrate technically when they execute a high rate of procedure-specific minor errors. However, when it comes to the major fundamental aspects of the operation, they dynamically adapt and migrate away from performing major technical errors. We aim to continue the study to increase cases, assess trainees as well, and also explore other factors that may affect the surgeon when executing surgical technical tasks.Presented at the 12th annual meeting of the European Association for Endoscopic Surgery, Barcelona, Spain, June 2004 相似文献
86.
87.
There is limited U.S. data on short- and long-term complications of laparoscopic adjustable gastric banding (LAGB) as a treatment option for morbid obesity. Hereafter, we present our experience with the first 154 consecutive LAGBs performed at Loyola University Medical Center. Inpatient and outpatient charts were reviewed retrospectively for all patients undergoing LAGB between November 2001 and February 2003 for perioperative morbidity and mortality and repeat operations. Thirty-seven men (24%) and 117 women (76%) underwent LAGB in a 16-month period. There was one (0.6%) death from postoperative myocardial infarction (MI) and one (0.6%) pulmonary embolism. Six (3.9%) patients required readmission to the hospital for dehydration. During a mean follow-up of 33 weeks (range, 4-69 weeks), 14 (9%) patients required repeat operations. There were five (3.2%) band slippages and one (0.6%) gastric erosion. Three bands were removed laparoscopically. Three slippages were revised laparoscopically. One patient underwent laparoscopic cholecystectomy. Seven patients (4.5%) required port revisions for catheter disconnection (4), leak at port site (2), or flipped port (1). LAGB is a safe operative approach for the management of morbid obesity. The incidence of postoperative complications can be minimal with application of a standardized technique. LAGB should be strongly considered for morbidly obese patients who have failed nonoperative management. 相似文献
88.
Systems approaches to surgical quality and safety: from concept to measurement 总被引:14,自引:0,他引:14 下载免费PDF全文
OBJECTIVE: This approach provides the basis of our research program, which aims to expand operative assessment beyond patient factors and the technical skills of the surgeon; to extend assessment of surgical skills beyond bench models to the operating theater; to provide a basis for assessing interventions; and to provide a deeper understanding of surgical outcomes. SUMMARY BACKGROUND DATA: Research into surgical outcomes has primarily focused on the role of patient pathophysiological risk factors and on the skills of the individual surgeon. However, this approach neglects a wide range of factors that have been found to be of important in achieving safe, high-quality performance in other high-risk environments. The outcome of surgery is also dependent on the quality of care received throughout the patient's stay in hospital and the performance of a considerable number of health professionals, all of whom are influenced by the environment in which they work. METHODS: Drawing on the wider literature on safety and quality in healthcare, and recent papers on surgery, this article argues for a much wider assessment of factors that may be relevant to surgical outcome. In particular, we suggest the development of an "operation profile" to capture all the salient features of a surgical operation, including such factors as equipment design and use, communication, team coordination, factors affecting individual performance, and the working environment. Methods of assessing such factors are outlined, and ethical issues and other potential concerns are discussed. 相似文献
89.
Yamaji K Sarker KP Abeyama K Maruyama I 《International journal of food sciences and nutrition》2004,55(1):61-66
It has been suggested that oxidation of low-density lipoprotein (LDL) plays an important role in the initiation and progression of atherosclerosis. In the present study, we determined the anti-atherogenic effects of egg yolk-enriched garlic powder (EGP), which has been used as a traditional health-promoting food in southern Japan since ancient times, on LDL oxidation and oxidant stress-induced cell injury models. We confirmed that EGP inhibits copper-induced LDL oxidation in a dose-dependent manner. We also observed that pretreatment of EGP significantly suppressed the production of peroxides in HL60 cells and protected endothelial cells from hydrogen peroxide-induced cell injury. These findings might, in part, be ascribed to the biodistribution of garlic compounds and egg yolk interaction, and suggest that EGP might be useful in the prevention of atherosclerosis. 相似文献
90.
Sarker CB Rahman S Siddiqui NI Huq MH Musa AK Talukder SI Alam KS Debnath CR Kabir AK Saleh FM 《Mymensingh medical journal : MMJ》2004,13(1):88-90
Thoracic actinomycosis represents about one-fourth of all cases of the disease. Isolated pleural effusion due to Actinomycosis is rare. We report a case of right sided pleural effusion with discharging sinus in the right anterior chest wall. Actinomycosis was suspected and confirmed by microscopic identification of "sulfur granules" in the discharge of the sinus tract and also identification of gram-positive filamentous bacteria in the specimen of discharging sinus. The patient improved clinically and radiologically after treatment with intravenous penicillin G followed by oral penicillin and aspiration of pleural fluid. 相似文献