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101.
BACKGROUND AND OBJECTIVES: Laparoscopy in patients with poor cardiac function has been the subject of controversy and is considered by many surgeons a relative contraindication. METHODS: We report the case of a patient who presented with acute cholecystitis and choledocholithiasis concurrent with unstable angina. Our experience in laparoscopic management of patients with calculous biliary disease and severe coronary artery disease is examined. RESULTS: The patient was managed by coronary angioplasty and stenting immediately followed by laparoscopic cholecystectomy and common bile duct exploration under close invasive hemodynamic monitoring and low-pressure pneumoperitoneum. Between 1996 and 2001, 39 patients with coronary artery disease and an ASA class of III or IV underwent laparoscopic cholecystectomy. Eight of these patients (20.5%) had common bile duct stones necessitating laparoscopic common bile duct exploration. No conversions were necessary, and no major morbidity or mortalities occurred. CONCLUSIONS: Laparoscopic cholecystectomy and common bile duct exploration can be safely performed in patients with severe ischemic cardiac disease under close hemodynamic monitoring and a low-pressure pneumoperitoneum (10 to 12 mm Hg).  相似文献   
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Variations in levels of motivation to learn among established general practitioners (GPs) have received scant attention. Building on previous work, we present an analysis of factors contributing to the development of motivation to learn in those who are entering and already established in practice. This approach suggests that individual motivation is both complex and unstable in response to external factors. We draw attention to the possibility of motivational immaturity in recruits to general practice, the contribution of values, and the presence of demotivators. The implications of our analysis are explored in relation to individual professional development and continuing education provision. We suggest that motivational audit will identify individual and contextual factors that are reducing the capacity of GPs to continue learning. A number of approaches addressing these factors are proposed.  相似文献   
103.
The cholinergic hypothesis of memory dysfunction has guided most of the recent proposals for treating the primary symptoms of AD. The efficacy of these treatments has been severely limited. This review examines two major lines of evidence which suggest that the cholinergic hypothesis may have to be expanded and revised. The cholinergic hypothesis focuses on pre-synaptic defects. It assumes cholinoceptive neurons would function normally with adequate stimulation. Evidence is not sufficient to support this assumption. In addition, dissociations have been demonstrated between muscarinic receptor number and functional response of cholinoceptive neurons. Various measures are proposed to investigate the functional integrity of muscarinic receptors in AD patients. AD often has been characterized as a disorder produced by generalized cholinergic hypoactivity. Evidence for cortisol hypersecretion, abnormal dexamethasone suppression, and the occurrence of depressive symptoms, motoric dysfunction and sleep abnormalities in AD patients is more consistent with regional cholinergic hyperactivity than generalized hypoactivity. Resolution of these discrepancies could shed new light on the pathophysiology and treatment strategies for AD. Cholinoceptive neurons could be hypersensitive, subsensitive or have unaltered responsivity. These options would have very different treatment implications. New developments in outcome assessment which are capable of discriminating varieties of differential response to treatment can spur treatment development and improve quality of care for patients with complex disorders such as AD.  相似文献   
104.
INTRODUCTION: Cerebral metastases are associated with a very poor prognosis. The best survival results are seen after surgical resection. However this involves a relatively invasive procedure and many patients are not suitable for surgical resection. We have evaluated the safety and efficacy of radiofrequency ablation of the brain in a sheep model. METHODS: We produced ablations of 1 - 3 cm diameter in the brain of sheep using the RITA starburst XL probe and RITA 1500 generator. We varied the time of RF application between 1 minute and 5 minutes and observed the animals for between 24 hours and 3 weeks for short-term and long-term effects and measured the intracranial pressure (ICP) in 2 animals following RFA. RESULTS: A total of 8 ablations were produced in 8 sheep. There was no change in the ICP measurements and there were no neurological complications in the 5 sheep with superficial ablation of up to 2 cm. Three sheep failed to regain consciousness due to large ablations near the brain stem and cerebellum. The sizes of the ablations were confirmed on necropsy and there was no other evidence of damage to the surrounding brain. Satisfactory ablation of brain was achieved at 70 degrees C and an ablation time as short as 3 minutes produced a 1.5 - 2.0 cm diameter of ablation. CONCLUSION: Cerebral RFA is a relatively safe and effective technique capable of producing a predictable ablation with no damage to surrounding brain. The potential of this technique requires further evaluation but likely advantages include the ability to treat multiple tumours and perform repeated treatment with a minimally invasive approach.  相似文献   
105.
Academic Achievement of Children with Epilepsy   总被引:31,自引:23,他引:8  
The academic achievement scores of 122 children with epilepsy were examined in relation to demographic and clinical seizure variables. As a group, these children were making less academic progress than expected for their age and IQ level. Academic deficiencies were greatest in arithmetic, followed by spelling, reading, comprehension, and word recognition. Results of the multiple regression analyses indicated a modest combined predictive significance of the demographic and clinical seizure variables for academic performance. In addition, the magnitude of these relationships varied by academic area. Among the individual variables examined the strongest correlates of academic performance were age of the child, age of seizure onset, lifetime total seizure frequency, and presence of multiple seizures (absence and tonic-clonic). These results are discussed in relation to developing an understanding of the factors which underlie academic vulnerability in children with epilepsy.  相似文献   
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Problems that can occur when single implants are utilized to restore first molar teeth include the frequent loosening of screws, as well as screws and/or implant breakage. These may result from torquing and rotational movements of the prosthesis during masticatory and parafunctional mandibular movements. When sufficient bone and mesio-distal restorative space is present, the placement of two implants should be considered.  相似文献   
110.
We have characterized the localization and the ontogenetic changes in Neuropeptide tyrosine (NPY) before birth and investigated the regulation of NPY expression by cortisol and undernutrition in the fetal sheep hypothalamus during late gestation. Using immunohistochemistry, we have identified NPY-containing neurons in the infundibular nucleus and the internal layer of the median eminence in fetal hypothalami collected between 110 and 147 days gestation. NPY projections were also present in the paraventricular nucleus (PVN) of fetal hypothalami at all ages between 110 days gestation and term. There was a significant increase in the amount of immunoreactive NPY/g hypothalamus between 87 and 113 days and 131–140 days gestation and a further significant increase after 141 days gestation. The total hypothalamic content of immunoreactive NPY increased significantly between 87 and 113 days and 141–145 days gestation. The levels of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus were significantly higher at 145–146 days gestation than at any earlier gestational age between 116 and 141 days gestation. Cortisol (2.5–3.0 mg/24 h) was infused intrafetally between 109 and 116 days gestation. The ratio of NPY mRNA: 18s rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the cortisol-infused group when compared with the saline-infused control group at 116 days gestation. Maternal, and hence fetal undernutrition, was induced between 110 and 146 days gestation. At 145–146 days gestation the ratio of NPY mRNA: 18S rRNA in the mediobasal region of the fetal hypothalamus was significantly higher in the undernutrition group when compared with control animals. We have therefore demonstrated that NPY is present in the hypothalamus of the sheep fetus before birth and that hypothalamic NPY content and NPY mRNA increase before delivery. We have also found that glucocorticoids and undernutrition stimulate increases in NPY mRNA levels in the hypothalamus before birth.  相似文献   
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