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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.
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   
73.
74.
This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor.  相似文献   
75.
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   
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77.
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   
78.
This study employs focus group methodology to explore gender differences in sunscreen use. Guided by the theory of reasoned action, males and females were found to differ on each of the following constructs: behavior, behavioral beliefs, and normative beliefs. Males and females differed in their sunscreen use, with females adopting a more preventive style of sunscreen use and males a more reactive style. Males and females differed in their salient beliefs that motivated their sunscreen use, many of which were related to traditional American gender roles. In addition, although males and females were aware of both positive and negative sources of normative beliefs regarding sunscreen use, females received more encouragement from their mothers and peers than males. Findings are discussed in terms of their implications for the design of future interventions.  相似文献   
79.
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc.  相似文献   
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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