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571.
Davis  PC; Hoffman  JC  Jr; Ball  TI; Wyly  JB; Braun  IF; Fry  SM; Drvaric  DM 《Radiology》1988,166(3):679-685
Eighty-one pediatric patients with a variety of spinal disorders, including suspected dysrhaphism, scoliosis, neoplasia, and neurofibromatosis, underwent magnetic resonance (MR) imaging. The results were retrospectively compared with those of myelography followed by computed tomography (CT) and surgery. In patients with dysrhaphism, most abnormalities, including hydromyelia, inclusion tumors, and sites of cord tether, were demonstrated with MR imaging. Diastematomyelia and small hydromyelic cavities were indistinguishable on routine coronal and sagittal T1-weighted images; axial images with T2 weighting were optimal for this differentiation. MR imaging did not enable direct visualization of a thickened filum or evaluation of tethering with a thin, dorsally positioned neural placode. Congenital or severe scoliosis required lengthy studies with multiple planes of imaging or myelography and CT. Milder curvatures were readily evaluated with MR imaging, and neoplastic lesions, with the exception of intrathecal tumor seeding, were adequately defined.  相似文献   
572.
Functional magnetic resonance imaging (fMRI) was applied to determine the involvement of the angular gyri in the processing of categorical and coordinate spatial relations. In a categorical task, subjects were asked to judge whether a dot was presented above or below a horizontal line. In a coordinate task, they were asked to judge whether or not the distance between the dot and the bar was within a reference distance. Results showed stronger activation of the left than of the right angular gyrus in the categorical task, and stronger activation, initially, of the right than of the left angular gyrus in the coordinate task. In addition, in the latter task, the involvement of the right angular gyrus decreased with practice while that of the left angular gyrus increased. These results are interpreted in terms of the development of new categorical representations with practice in the coordinate task.  相似文献   
573.
The relationship between the various haemodynamic abnormalities observed in cirrhosis and their prognostic value remains unclear. We report haemodynamic measurements on 96 patients with alcoholic cirrhosis (mean Childs-Pugh Score, CPS, 9.0 +/- 0.2, mean age 55.6 +/- 1.0 years) and assess their value in predicting variceal bleeding and death during a mean follow-up of 19.3 +/- 1.5 months. Baseline CPS correlated with hepatic venous pressure gradient (HVPG) (p = 0.001), azygos blood flow (p < 0.05), cardiac index (p < 0.05), and inversely with mean arterial pressure (p < 0.01) and systemic vascular resistance index (p < 0.05). Renal blood flow was not related to any haemodynamic parameter or CPS. Thirty-eight patients died during follow-up, and 16 had a variceal bleed. Death (p = 0.001) and variceal bleeding (p < 0.05) were more likely in patients with HVPG > 16 mmHg than in those with HVPG < 16 mmHg, and variceal bleeding was more likely in patients with HVPG > 12 mmHg (vs. HVPG < 12 mmHg, p < 0.05). HVPG also predicted death and variceal haemorrhage on univariate and multivariate analyses. No other haemodynamic parameter predicted death or bleeding. In alcoholic cirrhosis, severity of liver disease is related to HVPG, collateral blood flow and degree of systemic circulatory abnormalities. HVPG is a useful predictor of survival and variceal bleeding in these patients.   相似文献   
574.
575.

Background

Feeding practices after neonatal and congenital heart surgery are complicated and variable, which may be associated with prolonged hospitalization length of stay (LOS). Systematic assessment of feeding skills after cardiac surgery may earlier identify those likely to have protracted feeding difficulties, which may promote standardization of care.

Methods

Neonates and infants ≤3 months old admitted for their first cardiac surgery were retrospectively identified during a 1‐year period at a single center. A systematic feeding readiness assessment (FRA) was utilized to score infant feeding skills. FRA scores were assigned immediately prior to surgery and 1, 2, and 3 weeks after surgery. FRA scores were analyzed individually and in combination as predictors of gastrostomy tube (GT) placement prior to hospital discharge by logistic regression.

Results

Eighty‐six patients met inclusion criteria and 69 patients had complete data to be included in the final model. The mean age of admit was five days and 51% were male. Forty‐six percent had single ventricle physiology. Twenty‐nine (42%) underwent GT placement. The model containing both immediate presurgical and 1‐week postoperative FRA scores was of highest utility in predicting discharge with GT (intercept odds = 10.9, P = .0002; sensitivity 69%, specificity 93%, AUC 0.913). The false positive rate was 7.5%.

Conclusions

In this analysis, systematic and standardized measurements of feeding readiness employed immediately before and one week after congenital cardiac surgery predicted need for GT placement prior to hospital discharge. The FRA score may be used to risk stratify patients based on likelihood of prolonged feeding difficulties, which may further improve standardization of care.  相似文献   
576.
OBJECTIVES: In healthy subjects, the neural correlates of visceral pain bear much similarity with the correlates of somatic pain. In patients with irritable bowel syndrome, the central nervous system is believed to play a strong modulatory or etiological role in the pathophysiology of the disease. We hypothesize that this role must be reflected in aberrations of central functional responses to noxious visceral stimulation in these patients. To verify this hypothesis, we have induced transient rectal pain in patients and assessed the functional responses of the brain by means of functional magnetic resonance imaging. METHODS: Twelve right-handed patients (11 female) were examined. Functional imaging (1.5 T) was performed following a block paradigm, alternating epochs with and without noxious stimulation of the rectum. Rectal pain was induced by inflating a latex balloon. Whole-brain coverage was achieved by means of echo-planar magnetic resonance acquisition. RESULTS: A strong variability of the individual responses to rectal pain was found in patients with irritable bowel syndrome. Significant activations were found in only two patients, and group analysis did not reveal significant activations. In contrast, all patients exhibited significant deactivations. Group analysis revealed significant deactivations within the right insula, the right amygdala, and the right striatum. CONCLUSIONS: This study reveals aberrant functional responses to noxious rectal stimulation in patients with irritable bowel syndrome. Those results add grounds to the hypothesis that the central nervous system plays a significant role in the pathophysiology of this syndrome.  相似文献   
577.

Objectives

Coronary artery disease (CAD) is a leading cause of morbidity and mortality in the developed world and is rapidly assuming epidemic proportions in developing countries, including India. This has led to extensive research to determine the risk factors and the pathways that may predispose to the elevated risk of this disease. Important among them include lipoproteins, homocysteine, lipoprotein (a), pro-inflammatory cytokines and others. The following study was undertaken to determine a possible inter-relationship between inflammation and dyslipidaemia, which are important risk factors for CAD in the atherosclerosis-prone North Indian male population.

Methods

The study groups comprised 150 clinically assessed North Indian male patients with acute myocardial infarction (AMI), diagnosed on electrocardiographic and biochemical criteria, and 150 healthy controls. Apolipoprotein-AI (Apo-AI), apolipoprotein-B (Apo-B) and C-reactive protein (CRP) levels were estimated using kits based on the immunoturbidimetric assay from Randox, UK. Tumour necrosis factor-α (TNF-α) and lipoprotein (a) were assayed using commercially available ELISA kits from Diaclone Research, Belgium and Innogenetics, Belgium, respectively.

Results

The patients with AMI showed highly significant elevations in the levels of total serum cholesterol, triglycerides, LDL cholesterol, Apo-B and a significant decline in HDL cholesterol, compared with healthy controls. Significantly elevated serum levels of inflammatory markers, TNF-α and CRP were seen in patients with AMI, compared to the control subjects. A significantly positive correlation of TNF-α was observed with lipoprotein (a) in patients with CAD.

Conclusion

The data clearly underlines a possible interplay between inflammation and dyslipidaemia in the pathogenesis of CAD in the Indian context. This insight into the aetiopathogenesis of CAD will prove highly beneficial for devising better preventive measures and pharmacological interventions for CAD.  相似文献   
578.

Introduction

Mechanical ventilation (MV) is commonly regarded as a risk factor for acute kidney injury (AKI) in the critically ill. We investigated the strength of this association and whether settings of tidal volume (Vt) and positive end-expiratory pressure (PEEP) affect the risk for AKI.

Methods

We performed a systematic review and meta-analysis using studies found by searching MEDLINE, EMBASE, and references in relevant reviews and articles. We included studies reporting on a relation between the use of invasive MV and subsequent onset of AKI, or comparing higher with lower Vt or PEEP and subsequent onset of AKI. All studies clearly stating that MV was initiated after onset of AKI were excluded. We extracted the proportion with and without MV and AKI. We included 31 studies on invasive MV.

Results

The pooled odds ratio (OR) for the overall effect of MV on AKI was 3.16 (95% CI 2.32 to 4.28, P <0.001). Nearly all subgroups showed that MV increases the risk for AKI. The pooled OR for studies with a multivariate analysis including MV as a risk factor for AKI was 3.58 (95% CI 1.85 to 6.92; P <0.001). Different settings of Vt and PEEP showed no effect.

Conclusions

Invasive MV is associated with a threefold increase in the odds of developing AKI and various Vt or PEEP settings do not modify this risk. The latter argues in favour of a haemodynamic origin of AKI during MV.  相似文献   
579.
Aim. To establish the psychometric properties of the Chinese version of the State Self‐Esteem Scale in stroke patients. Background. Self‐esteem is seen to enhance peoples’ ability to cope with disease: low self‐esteem may inhibit participation in rehabilitation and thus result in poor health and social outcomes. Although the Chinese version of the State Self‐Esteem Scale has been used as an outcome measure for stroke rehabilitation, no study has examined its factor structure in this patient group. Design. A cross‐sectional design. Methods. A convenience sample of 265 Chinese stroke patients (mean age 71·4, SD 10·3 years), with a minimum score of 18 out of a possible 30 for the Mini Mental State Exam recruited from two regional rehabilitation hospitals in Hong Kong. An exploratory factor analysis and an internal consistency analysis of the State Self‐Esteem Scale were conducted. Pearson’s correlation coefficients were calculated between the State Self‐Esteem Scale and the Geriatric Depression Scale to determine convergent validity. Results. The final factor solution comprised a three‐factor model with correlated constructs and accounted for 49·5% of the total variance. Significant negative correlations were found between the Geriatric Depression Scale and the State Self‐Esteem Scale subscale scores (r?0·31 to ?0·55, p < 0·01), indicating that the State Self‐Esteem Scale had acceptable convergent validity. The new three‐factor structure had higher Cronbach’s alphas when compared with the original three‐factor structure. Relevance to clinical practice. The State Self‐Esteem Scale appears to be a useful measure for assessing state self‐esteem in stroke patients. To establish the concurrent, discriminative and construct validities, the factor structure of the SSES could be further developed and tested.  相似文献   
580.
ObjectiveTo investigate the antidiabetic and antioxidant activity of spent turmeric oleoresin (STO).MethodsAntidiabetic activity of STO evaluated by α-amylase and α-glucosidase enzyme inhibition assays. The antioxidant capacity studied by DPPH., ABTS., superoxide radical scavenging and metal chelating activity methods.ResultsThe STO showed good antidiabetic activity by inhibiting key enzymes linked to type 2 diabetes, viz α-glucosidase and α-amylase with an IC50values of 0.71 and 0.16μg/mL respectively. The IC50values for DPPH. and ABTS. assay were 58.1 and 33 μg/mL respectively. STO effectively scavenged the superoxide free radical with an IC50 value of 61.5μg/mL and showed a moderate iron chelation property.ConclusionsThe above study reveals that the spent turmeric oleoresin being wasted at present can be used as antioxidant and antidiabetic agent in food and neutraceutical products.  相似文献   
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