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951.
952.
The evoked EMG response commonly decreases in amplitude during the first few minutes of anaesthesia. The purpose of this study was to determine if a relationship exists between changes in hand temperature, which are known to occur with induction of anaesthesia, and drift in the EMG signal. The indirectly evoked response of the 1st dorsal interosseous muscle was measured using a Datex Relaxograph in 15 patients undergoing elective surgery. The test arm was wrapped in towels in order to minimize heat loss. Core body temperature, hand temperature, and T1 were recorded at two minute intervals for the next 30 min. Patients then received a bolus of mivacurium 0.08 mg.kg-1 and additional doses were given as needed. Complete recovery was defined as a TOF ratio > 0.90. Regression analysis plotting delta temperature against delta T1 was performed for each individual. The slope of the regression line for the relationship between delta degree C and delta T1 was then used to calculate a correction factor (CF) which might be used to "fine tune" the last measured T1. The initial hand temperature averaged 30.8 +/- 1.4 degrees C and this increased by 4.1 +/- 1.2 degrees C over the next 30 min. During this period T1 decreased by 24.8 +/- 5.9% or -6.05%/degrees C. The final mean T1 value at the end of anaesthesia (uncorrected) was 70.6 +/- 7% of control. The average corrected T1 value was 94.7 +/- 8.5% (range, 83-111%). It is concluded that there was a correlation between delta degree C and delta T1 during the first 30 min of anaesthesia (r2 = 0.77, P < 0.0001). However, in 5 of 15 individuals it was not possible to "temperature correct" the final T1 value to within +/- 10% of control. Hence, while changes in muscle temperature probably play a major role in the T1 drift seen with the Datex monitor, other factors remain to be identified.  相似文献   
953.
Results following liver transplantation for hepatocellular carcinoma have been dismal, attributed largely to recurrent disease locally or at distance sites. Undetected micrometastases or tumor that embolizes at the time of liver transplant from manipulation of the liver may account for these recurrences. A model and treatment protocol were developed to address this clinical problem. The protocol is modeled on the concept of bone marrow transplantation for leukemia. Hepatotoxins that are lethal to both normal hepatocytes and hepatoma cells are administered followed by liver transplantation to "rescue" the failing liver. The feasibility of this protocol was examined in a rat model. Male Buffalo rats were injected with 1 million Morris hepatoma MH-7777 cells intravenously at Day 0 as a model for micrometastatic disease. Three treatment groups were established. Group 1 received no treatment. Group 2 received 5% dextrose in water (D5W) followed by a syngeneic orthotopic liver transplant (OLTX). Group 3 received the hepatotoxin pyrazofuin (10 mg/kg) followed by OLTX. Animals were followed to Day 35, at which time they were sacrificed and examined for evidence of pulmonary metastases and quantitation of nodules with India ink insufflation. There was a significant decrease in the number with pulmonary nodules as well as the number of animals with pulmonary metastatic disease in the pyrazofurin-treated group compared with groups 1 and 2 (4.8 +/- 4.0 nodules/animal vs 45.2 +/- 11.2 nodules/animal--no treatment and 60.8 +/- 21.4 nodules animal--D5W/OLTX group) These data indicate that this model is reliable for examining metastatic hepatoma and that pyrazofurin is effective in preventing hematogenous micrometastases of hepatoma cells. Other hepatotoxins and the effect of allogeneic transplantation and immunosuppression could be examined in this model.  相似文献   
954.
A review of 150 consecutive endoprosthetic replacements for acute displaced femoral neck fractures was undertaken to investigate the following serious criticisms of the method. The first is excessive hospital mortality and morbidity, especially in comparison to internal fixation procedures retaining the femoral head. The second is pain, derived from the "unphysiologic" nature of placing a metal prosthesis against otherwise normal acetabular cartilage. In the first instance the procedure is condemned as too major an operative procedure, poorly tolerated by elderly patients. In the second, it is a poor procedure if it requires revision in a patient incapable of withstanding more than one operation. A detailed follow-up shows that the in-hospital mortality in patients averaging 79.8 years of age, was 4%, lower than published mortality for either hemiarthroplasty or internal fixation. Close postoperative monitoring, antibiotic and antiembolic prophylaxis (2.0% infection, 6% embolic complications), and rapid mobilization contributed significantly to the increased survival. Painful endoprostheses, the most frequent complication, occurred in 16.7% of the 125 patients available for follow up at an average of 21 months. The causes of pain were considered technical problems judging prosthetic neck length, head size, sinking and loosening. Dissolution of the medial femoral neck was associated with a narrow stem prosthesis in five of six of these failures. The above statistics suggest that primary endoprosthetic replacement for displaced femoral neck fractures carries with it neither the excessive mortality and morbidity nor the pain induced potential for early reoperations that have been suggested by the recent literature.  相似文献   
955.
Television epilepsy and pattern sensitivity   总被引:2,自引:0,他引:2  
Properly functioning domestic television sets may induce seizures in epileptic patients (TV epilepsy). We investigated the effects of different types of visual stimuli on paroxysmal electroencephalographic (EEG) activity in 32 patients known to be sensitive to intermittent photic stimulation (stroboscopic light). We monitored sensitivity to patterns of horizontal and vertical lines, both stationary and vibrated (pattern sensitivity), and to normal broadcasts on a domestic, black and white (405- or 625-line) TV receiver (TV sensitivity). Twenty-three of the 32 patients were sensitive to pattern. Twenty-two were sensitive to vibrated patterns, and 11 to static patterns (P less than 0-01), All patients sensitive to pattern were also sensitive to TV; The association between sensitivity to pattern and to TV was significant. Clinical history of TV epilepsy (16 out of 32 patients) and laboratory evidence of pattern or TV sensitivity were not significantly associated. The high incidence of pattern sensitivity among flicker-sensitive patients and its association with TV sensitivity suggests that linear patterns produced by the raster of a black and white set as it scans, or "line-jitter" produced by the raster in areas of low TV-signal strength may contribute to the epileptogenic effect of TV.  相似文献   
956.
Between 1988 and 1992 new rules were enacted to open the EU utilities procurement market to increased competition. The aim was to end national preference for local suppliers and to encourage increased cross-border trade both from within the EU and, when appropriate, from countries outside. This article draws on data that analyse the impact of the new rules on utilities procurement in 1993. The data show that so far the new rules have not significantly altered the preference of EU member states for procurement from locally based suppliers.  相似文献   
957.
In essence, the virtual physiological human (VPH) is a multiscale representation of human physiology spanning from the molecular level via cellular processes and multicellular organization of tissues to complex organ function. The different scales of the VPH deal with different entities, relationships and processes, and in consequence the models used to describe and simulate biological functions vary significantly. Here, we describe methods and strategies to generate knowledge environments representing molecular entities that can be used for modelling the molecular scale of the VPH. Our strategy to generate knowledge environments representing molecular entities is based on the combination of information extraction from scientific text and the integration of information from biomolecular databases. We introduce @neuLink, a first prototype of an automatically generated, disease-specific knowledge environment combining biomolecular, chemical, genetic and medical information. Finally, we provide a perspective for the future implementation and use of knowledge environments representing molecular entities for the VPH.  相似文献   
958.
The present study compared the attitudes and feelings of law-enforcement, corrections, parole and probation personnel, and college students toward mental illness. Modified versions of the Criminally Insane Scale (Khanna, Pratt, & Gardiner, 1962) and Attitudes Toward Mental Illness Scale (Cohen & Struening, 1962) were used in assessing these attitudes. Law-enforcement and corrections personnel tended to believe many of the stereotypic causes of mental illness, while the college students based their views on more current thinking. In addition, law-enforcement and corrections personnel indicated greater fear of the criminally insane than the other two groups. Possible causes and ramifications of these differences are discussed.  相似文献   
959.
Self-care, although growing as a concept and a movement among providers and consumers, has not been studied systematically in any dimension. Because of the potential role of physicians in establishing the credibility and acceptability of self-care interventions and practices, an exploratory investigation was launched to develop an attitude instrument, to describe the degree to which practicing physicians in a community favor self-care, and to explore some of the correlates of the attitudes expressed. A 13-item attitude scale was developed. Physicians with the most favorable attitudes were most likely to have come from a Jewish religious background, to be under 46 years old, to have health beliefs which reflect an internal locus of control, and to be in a group practice or clinic. Physicians with the least favorable attitudes came from Protestant backgrounds, were 46 to 63 years old, had externally controlled health beliefs, and practiced medicine alone.  相似文献   
960.
In two of 182 patients with verified primary hyperparathyroidism, microscopical hyperplasia was present in all parathyroid glands that were normal in size or only slightly enlarged. All parathyroid glands in another two patients showed microscopical hyperplasia and varied from a normal size of 190 mg. In seven additional patients, microscopical hyperplasia was present in one, several, or all parathyroid glands, which varied in weight from normal to 350 mg. Familial hyperparathyroidism or multiple endocrine neoplasia was evident in five of 11 patients. Contributing to difficulties was the experience in five patients in whom removal of mildly enlarged parathyroid glands corrected hypercalcemia, but definite microscopical abnormalities were not evident by routine histologic study of the glands. Thus, there appears to be a spectrum of abnormalities relative to size and microscopical changes in parathyroid glands of patients with primary hyperparathyroidism. The surgeon should be aware of these patterns of parathyroid hyperplasia that require a search for a fifth parathyroid gland and a subtotal parathyroidectomy.  相似文献   
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