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971.
972.
OBJECTIVE: To describe changes in delay to administration of thrombolytic therapy associated with a region-wide audit. DESIGN: Observational study of patients admitted with suspected myocardial infarction (MI) based on continuous audit. SUBJECTS: 18877 patients admitted to 23 hospitals with suspected MI between April 1995 and March 1998. RESULTS: Of 11232 patients with a discharge diagnosis of definite MI, 8802 (46.6%) received thrombolytic therapy during hospitalisation, with 5155 patients eligible for treatment on admission to hospital on the basis of established indications. Call-to-needle time for those eligible for treatment on admission fell from median 105 min in the first year of the project to 85 min in year 3 (P<0.001), and door-to-needle time fell from 45 to 35 min (P<0.001). Forty percent of eligible patients were treated within the then current national standard of 90 min from time of call for help, with nearly 49% in the final year and 20% being treated within the new national standard of 60 min, by the third year. CONCLUSION: The proportion of eligible patients receiving thrombolysis within 1 h of the call for help doubled during the 3-year project but the majority of patients still wait longer than 60-min 'call-to-needle'. New systems to reduce delays to administration of thrombolysis to within 60 min of call for help are required, including consideration of pre-hospital treatment.  相似文献   
973.
Sedation in critically ill patients is a complex issue and at the same time an important concept for ensuring patient comfort. The aim of this study was to review the current practice of sedation for patients on mechanical ventilation in Swedish intensive care units (ICUs). Questionnaires were sent by post to head nurses in 89 ICUs with mechanically ventilated patients. By August 2000, 87 (98%) questionnaires had been returned. The results show that mechanically ventilated patients were routinely sedated in 91% of ICUs. Midazolam or propofol in combination with an opioid were the drugs preferred by 76%. Heavy sedation was most usual in 63% of ICUs but, when asked about the sedation level preferred by nurses, 78% chose light sedation (P=0.001). Only 16% used sedation scales. This study indicates that local habits and personal attitudes seem to have a great impact on sedation routines. It therefore appears worthwhile for ICUs to review their practice and, if necessary, to consider implementing sedation scales and sedation guidelines. Research pertaining to potential complications and patient comfort in relation to different sedation levels as well as further validation of the efficacy of sedation scales is needed.  相似文献   
974.
Serum anti-T cell receptor (TCR) Ab's are involved in immune regulation directed against pathogenic T cells in experimental models of autoimmune diseases. Our identification of a dominant T cell population expressing the Vbeta5.1 TCR gene (TCRBV5-1), which is responsible for the production of pathogenic anti-acetylcholine receptor (AChR) autoantibodies in HLA-DR3 patients with early-onset myasthenia gravis (EOMG), prompted us to explore the occurrence, reactivity, and regulatory role of anti-TCR Ab's in EOMG patients and disease controls with clearly defined other autoantibodies. In the absence of prior vaccination against the TCR, EOMG patients had elevated anti-Vbeta5.1 Ab's of the IgG class. This increase was restricted largely to EOMG cases with HLA-DR3 and with less severe disease, and it predicted clinical improvement in follow-up studies. EOMG patient sera containing anti-TCR Ab's bound specifically the native TCR on intact Vbeta5.1-expressing cells and specifically inhibited the proliferation and IFN-gamma production of purified Vbeta5.1-expressing cells to alloantigens in mixed lymphocyte reaction and the proliferation of a Vbeta5.1-expressing T cell clone to an AChR peptide, indicating a regulatory function for these Ab's. This evidence of spontaneously active anti-Vbeta5.1 Ab's in EOMG patients suggests dynamic protective immune regulation directed against the excess of pathogenic Vbeta5.1-expressing T cells. Though not sufficient to prevent a chronic, exacerbated autoimmune process, it might be boosted using a TCR peptide as vaccine.  相似文献   
975.
Once abandoned because of devastating teratogenic effects, thalidomide has reemerged as an alternative treatment in many dermatologic diseases. In 1998, thalidomide became FDA approved for the acute treatment and suppression of the cutaneous manifestations of erythema nodosum leprosum (ENL). ENL is a systemic disorder that typically occurs after several years of antileprosy treatments, usually for lepromatous leprosy. Off-label uses for thalidomide include: aphthous stomatitis, Beh?et disease, pyoderma gangrenosum, chronic discoid lupus erythematosus, systemic lupus erythematosus, lichen planus, prurigo nodularis and sarcoidosis. This review examines the background, pharmacokinetics, mechanism of action, side-effects, and indications of thalidomide.  相似文献   
976.
Purpose

The aims of this study were to evaluate the diagnostic accuracy of the dual imaging method combining cardiac iodine-123-metaiodobenzylguanidine single-photon emission computed tomography combined with low-dose chest computed tomography compared to routine cardiac scintigraphy, and assess regional differences in tracer distribution and the relationships between imaging and autonomic function in Parkinson’s disease and multiple system atrophy.

Methods

A prospective study including 19 Parkinson’s disease and 12 multiple system atrophy patients was performed. Patients underwent clinical evaluation, iodine-123-metaiodobenzylguanidine single-photon emission computed tomography combined with chest computed tomography, planar scintigraphy, and cardiovascular autonomic function tests.

Results

Co-registration of single-photon emission computed tomography and chest computed tomography resulted in three groups with distinct patterns of tracer uptake: homogeneous, non-homogeneously reduced and absent. There was a significant difference in group allocation among patients with multiple system atrophy and Parkinson’s disease (p?=?0.001). Most multiple system atrophy patients showed homogeneous uptake, and the majority of Parkinson’s disease patients showed absent cardiac tracer uptake. We identified a pattern of heterogeneous cardiac tracer uptake in both diseases with reductions in the apex and the lateral myocardial wall. Sympathetic dysfunction reflected by a missing blood pressure overshoot during Valsalva manoeuvre correlated with cardiac tracer distribution in Parkinson’s disease patients (p?<?0.001).

Conclusions

The diagnostic accuracy of the dual imaging method and routine cardiac scintigraphy were similar. Anatomical tracer allocation provided by the dual imaging method of cardiac iodine-123-metaiodobenzylguanidine single-photon emission computed tomography and chest computed tomography identified a heterogeneous subgroup of Parkinson’s disease and multiple system atrophy patients with reduced cardiac tracer uptake in the apex and the lateral wall. Sympathetic dysfunction correlated with cardiac imaging in Parkinson’s disease patients.

  相似文献   
977.
978.
Trauma to the spinal cord rarely results in complete division of the cord with surviving nerves sometimes remaining silent or failing to function normally. The term motor or sensory discomplete has been used to describe this important but unclassified subgroup of complete SCI. Importantly, silent motor or sensory pathways may contribute to aversive symptoms (spasticity, pain) or improved treatment success. To demonstrate more objectively the presence of subclinical preserved somatosensory pathways in clinically complete SCI, a cross‐sectional study using functional MRI (fMRI) was undertaken. The presence of brain activation following innocuous brushing of an insensate region below‐injury (great toe) was analyzed in 23 people (19 males (83%), mean ± SD age 43 ± 13 years) with clinically complete (AIS A) SCI with (n = 13) and without (n = 10) below‐level neuropathic pain and 21 people without SCI or pain (15 males (71%); mean ± SD age 41 ± 14 years). Location appropriate, significant fMRI brain activation was detected in 48% (n = 11/23) of subjects with clinically complete SCI from below‐injury stimulation. No association was found between the presence of subclinical sensory pathways transmitting innocuous mechanical stimuli (dorsal column medical lemniscal) and below‐level neuropathic pain (χ2 = 0.034, P = 0.9). The high prevalence of sensory discomplete injuries (~50% complete SCI) strengthens the case to explore inclusion of this category into the international SCI taxonomy (ISNCSCI). This would ensure more widespread inclusion of discomplete SCI in ongoing pain and motor recovery research. Neurophysiological tests such as fMRI may play a role in this process. Hum Brain Mapp 39:588–598, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
979.
This study measured episodic memory deficits in individuals with mild cognitive impairment (MCI) as a function of their vascular burden. Vascular burden was determined clinically by computing the number of vascular risk factors and diseases and neuroradiologically by assessing the presence and severity of white matter lesions (WML). Strategic memory processes were measured with free recall and temporal contextual memory tasks requiring self-initiated retrieval. Nonstrategic memory retrieval processes were appraised with a five-choice recognition procedure. Results showed that MCI participants with high vascular burden displayed impairment of strategic memory processes, whereas MCI participants with no vascular burden showed impairment of both strategic and nonstrategic memory processes. A similar pattern was found whether vascular burden was measured using a clinical index of vascular risk profile or whether it was measured neuroradiologically by assessing the extent and severity of subcortical WML. However, the effect of WML on memory differed as function of level of education, used here as a proxy for cognitive reserve. Among participants with MCI, those who had higher education and no WML were the least memory impaired. The study also examined memory as a function of whether patients later progressed to dementia after a three-year follow-up. When examining progressors’ performance, strategic and nonstrategic processes were both impaired in progressors with no concomitant vascular conditions, whereas progressors with a high vascular burden showed less impairment of nonstrategic than strategic processes. Overall, results indicate that the presence of vascular burden in MCI is associated with selective impairment of strategic memory processes.  相似文献   
980.
IntroductionStudents who are enrolled in professional education programs such as occupational therapy may have inherent attitudes towards the future clients they work with. These attitudes may be influenced by the level of their professional education as well as cultural values of their country of origin.PurposeThe purpose of the study was to examine occupational therapy students’ attitudes towards individuals with disabilities from an international, cross-cultural perspective and to investigate the possible impact of professional education on students’ attitudes.Method485 occupational therapy students from 11 university programs (3 from Australia, 3 from the United Kingdom, 3 from the United States, and 2 from Taiwan) completed the Interactions with Disabled Person's (IDP) scale.ResultsSignificant differences were found between occupational therapy students from Australia, Taiwan, the United States, and the United Kingdom on the following IDP variables: overall attitude towards individuals with disabilities, ‘discomfort’, ‘sympathy’, ‘uncertainty’, ‘coping’, ‘fear’, and ‘vulnerability’. Significant differences between first year students as a total group and final year students as a total group were found on their overall attitudes towards individuals with disabilities, ‘discomfort’, and ‘uncertainty’.Conclusion/implicationsThe attitudes towards individuals with disabilities among first year and final year occupational therapy students varies between countries and the students’ year level also impacts on their attitudes towards individuals with a disability.  相似文献   
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