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71.
We measured CBF and the CMRglc in normal controls and in patients with severe liver disease and evidence for minimal hepatic encephalopathy using positron emission tomography. Regions were defined in frontal, temporal, parietal, and visual cortex; the thalamus; the caudate; the cerebellum; and the white matter along with a whole-slice value obtained at the level of the thalamus. There was no difference in whole-slice CBF and CMRglc values. Individual regional values were normalized to the whole-slice value and subjected to a two-way repeated measures analysis of variance. When normalized CBF and CMRglc values for regions were compared between groups, significant differences were demonstrated (F = 5.650, p = 0.00014 and F = 4.58, p = 0.0073, respectively). These pattern differences were due to higher CBF and CMRglc in the cerebellum, thalamus, and caudate in patients and lower values in the cortex. Standardized coefficients extracted from a discriminant function analysis permitted correct group assignment for 95.5% of the CBF studies and for 92.9% of the CMRglc studies. The similarity of the altered pattern of cerebral metabolism and flow in our patients to that seen in rats subjected to portacaval shunts or ammonia infusions suggests that this toxin may alter flow and metabolism and that this, in turn, causes the clinical expression of encephalopathy.  相似文献   
72.
Digital archive center: implementation for a radiology department.   总被引:2,自引:0,他引:2  
OBJECTIVE. In this article, we describe the implementation of a digital archive center for a radiology department in a 700-bed teaching hospital. MATERIALS AND METHODS. The archive center consists of two identical archive systems, each comprising five components: an archive server, a data-base server, an optical disk library, a stand-alone optical disk drive, and a communication network. An image management system controls the image traffic from acquisition devices to display stations. A fault-tolerant mechanism was built into the archive center to achieve a 100% uptime. RESULTS. The center has been in operation for over 6 months. We have not experienced a single total system failure during this period. It currently archives all digital images from three MR units and four CT scanners and selected images from three computed radiographic systems and two laser film digitizers. The center archives between 1.5 and 2.0 gigabytes of images per workday. CONCLUSION. With its built-in fault-tolerant mechanism, we believe that the implemented archive center is very reliable and is suitable for a radiology department to archive its digital images.  相似文献   
73.
C M Lo  S T Fan  C L Liu  W I Wei  R J Lo  C L Lai  J K Chan  I O Ng  A Fung    J Wong 《Annals of surgery》1997,226(3):261-270
OBJECTIVE: The authors report their experience with living donor liver transplantation (LDLT) using extended right lobe grafts for adult patients under high-urgency situations. SUMMARY BACKGROUND DATA: The efficacy of LDLT in the treatment of children has been established. The major limitation of adult-to-adult LDLT is the adequacy of the graft size. A left lobe graft from a relatively small volunteer donor will not meet the metabolic demand of a larger recipient. METHODS: From May 1996 to November 1996, seven LDLTs, using extended right lobe grafts, were performed under high-urgency situations. All recipients were in intensive care units before transplantation with five having acute renal failure, three on mechanical ventilation, and all with hepatic encephalopathy. The median body weight for the donors and recipients was 58 kg (range, 41-84 kg) and 65 kg (range, 53-90 kg), respectively. The body weights of four donors were less than those of the corresponding recipients, and the lowest donor-to-recipient body weight ratio was 0.62:1. The extended right lobe graft was chosen because the left lobe volume was <40% of the ideal liver mass of the recipient. RESULTS: Median blood loss for the donors was 900 mL (range, 700-1600 mL) and hospital stay was 19 days (range, 8-22 days). Homologous blood transfusion was not required. Two donors had complications (one incisional hernia and one bile duct stricture) requiring reoperation after discharge. All were well with normal liver function 5 to 10 months after surgery. The graft weight ranged from 490 g to 1140 g. All grafts showed immediate function with normalization of prothrombin time and recovery of conscious state of the recipients. There was no vascular complication, but six recipients required reoperation. One recipient died of systemic candidiasis 16 days after transplantation and 6 (86%) were alive with the original graft at a median follow-up of 6.5 months (range, 5-10 months). CONCLUSIONS: When performed by a team with experience in hepatectomy and transplantation, LDLT, using an extended right lobe graft, can achieve superior results. The technique extends the success of LDLT from pediatric recipients to adult recipients and opens a new donor pool for adults to receive a timely graft of adequate function.  相似文献   
74.
Geographic clustering of human T cell lymphoma/leukaemia virus type 1 (HTLV-1) infection is well recognised, particularly in south western Japan, parts of West and Central Africa, the south eastern United States and the Caribbean islands. Sporadic cases have been reported in many other parts of the world. The first case of HTLV-1 associated leukaemia/lymphoma (ATLL) in South East Asia is reported. Contact tracing showed a high incidence of carriers among the relatives.  相似文献   
75.
76.
PURPOSE: To describe the outbreak of severe acute respiratory syndrome (SARS) in Toronto, its impact on anesthesia practice and the infection control guidelines adopted to manage patients in the operating room (OR) and to provide emergency intubation outside the OR. Clinical features: The SARS outbreak in Toronto was the result of a single index patient. The causative virus, SARS-CoV, is moderately contagious, and is spread by droplets and contact. The virus gains access to host through the mucosa of the respiratory tract and the eyes. It can affect both healthy and compromised patients. The use of several precautionary measures such as goggles, gloves, gowns and facemasks and the application of various infection control strategies designed to minimize the spread of the virus are discussed. CONCLUSION: In containing the spread of SARS, vigilance and strict infection control are important. This results in the rediscovery of standards of infection control measures in daily anesthesia practice.  相似文献   
77.
An audit of the safety of an acute pain service   总被引:9,自引:0,他引:9  
We audited and analysed the adverse effects and safety of postoperative pain management on 2509 consecutive patients under care of the Acute Pain Service at a tertiary referral teaching hospital over a 32-month period. Our standard respiratory monitoring consisted of continuous pulse oximetry, hourly respiratory rate counting, sedation scoring and intermittent arterial blood gas sampling. This protocol was reliable and detected six episodes of bradypnoea, 13 of hypercapnia and 23 of oxygen desaturation occurring in 39 patients (1.8% of all spontaneously breathing patients) . Two patients required naloxone injection and none had long-term sequelae. Hypotension due to epidural bupivacaine 0.0625% and fentanyl 3.3 μg.ml−1 infusion occurred in four patients (1.2%), all with a sensory block higher than T5. They readily responded to fluid infusion and ephedrine (two patients). Postoperative nausea or vomiting occurred in 723 (28.8%) and 380 (15.1%) patients, respectively. Odds ratio analysis showed that the risk factors for postoperative nausea and vomiting were: female gender, gynaecological operations, nongeriatric patients and systemic analgesia. Postoperative nausea and vomiting decreased analgesic efficacy by discouraging the use of patient-controlled analgesia and was regarded as equally distressing as pain. Other side-effects included: pruritus in 182 patients; dizziness in 333 and lower limb weakness in 73 (21.2% of patients receiving epidural local anaesthetics). It is concluded that a standard monitoring and management protocol, an experienced nursing team and reliable Acute Pain Service coverage is mandatory for the safe use of modern analgesic techniques.  相似文献   
78.
In both saline-injected control and streptozotocin-induced diabetic rats, insulin-like immunoreactivity was localized in the cervical, thoracic, lumbar and sacral segments of the spinal cord. This insulin-like immunoreactivity was consistently localized in the neurons and dendrites from control rats as well as from diabetic rats ranging from 1 month to 12 months after diabetes induction. In the neuronal cell bodies, the reaction product was predominantly localized in the cell nucleus and the proximal and distal dendrites. In the labelled cell nucleus, the reaction product was scattered throughout the cell cytoplasm and nucleoplasm, but not within the nucleolus. The inner and outer nuclear membranes were also labelled. In labelled dendrites, the reaction product was closely associated with the parallel arrays of neurotubules, plasma membranes and synaptic densities. Most of the labelled distal dendrites were postsynaptic to unlabelled axon terminals. A labelled dendrite often formed the central element of a synaptic glomerulus with several unlabelled axon terminals. It is hereby hypothesized that some of the neurons in the spinal cord of the diabetic rat are capable of synthesizing insulin-like substance(s), which appears to be involved in neurotransmission and neuromodulation.  相似文献   
79.
80.
Surgical resection for metastatic melanoma to the lung   总被引:5,自引:0,他引:5  
From 1971 through December 1986, the courses of 47 patients who underwent thoracotomy for pulmonary metastases from melanoma were retrospectively reviewed to determine the efficacy of this approach in the management of selected patients with melanoma. The overall five-year survival rate was 25% (median survival, 19 months). Thirty-eight patients were free of disease following thoracotomy. These patients fared significantly better than those who had residual disease following thoracotomy, with a five-year survival rate of 31% (median survival, 24 months) compared with 0% (median survival, six months). Survival was not influenced by the addition of adjuvant therapy or duration of time before the development of metastases (less than 12 months vs greater than or equal to 12 months). In selected patients with melanoma metastatic to the lung, thoracotomy with complete excision of the metastatic deposits results in improved survival and should be considered the treatment of choice.  相似文献   
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