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41.
S. T. Fan Q. S. Wang C. M. Lo K. W. Tam Yu E. C. S. Lai J. Wong 《ANZ journal of surgery》1994,64(11):759-762
Impaired hepatic function is a major contributory factor to the high incidence of postoperative morbidity and mortality in patients with malignant biliary obstruction. Dynamic hepatic function tests such as indocyanine green (ICG) retention and aminopyrine breath tests were evaluated in such patients to define whether they were clinically useful for prediction of postoperative morbidity and mortality. Forty-four patients with malignant biliary obstruction undergoing surgery for relief of obstructive jaundice were recruited into the study. Indocyanine green retention and aminopyrine breath tests were carried out in all patients pre-operatively and repeated in 36 patients postoperatively. The ICG retention was abnormal in all patients before surgery and there was significant improvement 2 weeks after surgery (32.8 ± 2.5%vs 18.3 ± 2.8%, P= 0.001). The change in ICG retention levels correlated with the serum bilirubin levels but the pre-operative ICG retention value could not predict postoperative morbidity and mortality. The aminopyrine breath test was abnormal in all but one patient. It correlated with pre-operative prothrombin time of the patients before surgery but it did not improve significantly after surgery and was not predictive of postoperative outcome. It is concluded that both ICG retention and aminopyrine breath tests have limited clinical value in the pre-operative evaluation of patients with malignant biliary obstruction. 相似文献
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43.
Emiri Tejima Bing-Qiao Zhao Kiyoshi Tsuji Anna Rosell Klaus van Leyen R Gilberto Gonzalez Joan Montaner Xiaoying Wang Eng H Lo 《Journal of cerebral blood flow and metabolism》2007,27(3):460-468
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema. 相似文献
44.
BACKGROUND AND PURPOSE: Early identification of predictive factors relevant to functional outcomes for stroke patients is important to the establishment of an effective continuing care program. The objective of this study was to identify the predictive factors related to functional outcome at discharge after stroke rehabilitation therapy. METHODS: 105 first-time stroke patients admitted to the inpatient rehabilitation department of a university-based medical center were recruited for this prospective study. The functional outcomes of the patients were assessed at admission and at discharge using the Functional Independence Measure (FIM). Severity of stroke was determined using the Canadian Neurological Scale (CNS). Age, gender, side of hemiplegia (SIDE), type of stroke (TYPE), onset to admission interval (OAI), and length of rehabilitation stay (LORS) were also included as predictor variables. RESULTS: The mean (+/- SD) FIM score at discharge (76.6 +/- 26.4) correlated strongly (r = 0.78, p < 0.001) with the admission FIM score (56.3 +/- 24.1), moderately (r = 0.46, p < 0.001) with the admission CNS score (6.1 +/- 2.2), negatively (r = -0.38, p < 0.001) with age (63.2 +/- 12.3 years), negatively (r = -0.26, p = 0.009) with OAI (24.2 +/- 16.0 days), and negatively (r = -0.29, p = 0.002) with LORS (34.7 +/- 16.8 days). Stepwise regression analyses indicated that admission FIM score, age, and admission CNS score were the strongest predictors of functional outcome and accounted for 66% of the total variation in discharge FIM total score. The admission FIM score was the best predictor and accounted for 61% of the variation. CONCLUSIONS: The findings of this study imply that the admission FIM scores for inpatients receiving stroke rehabilitation can be used to predict functional outcomes at discharge from hospital. 相似文献
45.
Motor imagery (MI), which refers to the process of mental representation of movements, has not been studied in patients with essential tremor (ET). We investigated the presence of impaired MI in ET patients compared with healthy controls. A group of drug-naive and nondemented ET patients and age-matched controls were studied using transcranial magnetic stimulation, while they were specifically instructed to try and imagine themselves performing two motor tasks. The various clinical and electrophysiological variables were evaluated and compared. Repeated measures ANOVA demonstrated a significant difference between ET patients and controls with respect to mean motor-evoked potential (MEP) amplitudes (F(1,38) = 31.92, P < 0.005) during MI. The process of MI effectively facilitated MEP amplitude in controls but not in ET patients, regardless of side of stimulation or motor tasks. We provide evidence to demonstrate impairment of MI in a group of ET patients compared with healthy controls. The basis for this novel finding is unclear, and further studies are warranted to determine whether it is related to cerebellar or motor cortical dysfunction. 相似文献
46.
Focal task-specific dystonia (FTSD) of the hand and face have been well described; however, FTSD of the leg is exceedingly rare. We describe and demonstrate by videotape 2 patients with FTSD affecting the leg, in both cases triggered specifically by walking down steps. Walking on a level surface, up steps, and down steps backward, and sideways were normal. An interoceptive sensory trick (imagining walking in a different modality) led to temporary improvement. Our patients appear to demonstrated that task-specificity in focal dystonia may not be limited to skilled, rehearsed actions and that FTSD may occur in an activity that is relatively autonomic. 相似文献
47.
Ptosis is known to be associated with thyroid disorders. We describe two biochemically corrected hypothyroid patients presenting with isolated bilateral ptosis. EMG of the orbicularis oculi showed continuous grouped motor unit potentials. In the absence of obvious aetiology, it is hypothesised that focal demyelination of terminal branches to the orbicularis oculi may play a role in the generation of the discharges. 相似文献
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49.
Mistakes are inevitable in medicine. To learn how medical mistakes relate to subsequent changes in practice, we surveyed 254 internal medicine house officers. One hundred and fourteen house officers (45%) completed an anonymous questionnaire describing their most significant mistake and their response to it. Mistakes included errors in diagnosis (33%), prescribing (29%), evaluation (21%), and communication (5%) and procedural complications (11%). Patients had serious adverse outcomes in 90% of the cases, including death in 31% of cases. Only 54% of house officers discussed the mistake with their attending physicians, and only 24% told the patients or families. House officers who accepted responsibility for the mistake and discussed it were more likely to report constructive changes in practice. Residents were less likely to make constructive changes if they attributed the mistake to job overload. They were more likely to report defensive changes if they felt the institution was judgmental. Decreasing the work load and closer supervision may help prevent mistakes. To promote learning, faculty should encourage house officers to accept responsibility and to discuss their mistakes. 相似文献
50.
Desmond FS Cormack RMN RGN MPhil DipEd PhD DipN Honorary Reader in Health Nursing William Reynolds RMN RNT RGN MPhil Senior Tutor 《Journal of advanced nursing》1992,17(12):1472-1478
Arguably, nursing, like all health care disciplines, is an applied science. Essentially, this refers to the application of theory in order to understand and respond to the health problems of clients. These theories may be drawn (borrowed) from any applied science, or generated inductively from clinical nursing practice. Alternatively, nurses may attempt to apply deductive theory (global theoretical frameworks) known as nursing models. In this paper, all theoretical approaches, irrespective of origin, are referred to as models used by nurses. Thirteen criteria by which clinicians, and others, can evaluate the clinical and practical utility of models used by nurses which are expressed in the form of questions are identified and discussed. The criteria are an extension, both in detail and in number, of those developed by Reynolds and Cormack and subsequently applied by those writers to the Johnson Behavioural System Model of Nursing. The value, or otherwise, of individual models, or of models in general, will not be discussed in this paper. However, the authors propose that if the evaluation criteria described here are applied to existing models, serious deficits will be identified in relation to their clinical and practical utility. 相似文献