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OBJECTIVE: To investigate the long-term effects of shunting on neurologic outcome of syringomyelia, a complication of spinal cord injury (SCI). DESIGN: Retrospective data collection using telephonic survey. SETTING: University based medical center. PARTICIPANTS: Eight of 15 patients who had shunts placed between 1976 and 1999. INTERVENTIONS: Review of clinical records and self-reported telephone interview. MAIN OUTCOMES MEASURES: Initial clinical presentation, recovery after shunt placement, and subsequent neurologic status were recorded. Patients were asked to rate symptomatic improvement after surgery on a 100-point analog scale; they were also asked whether they would have the surgery again. RESULTS: Presenting symptoms were weakness in all 8 patients, pain in 5 patients, and numbness in 5 patients. After shunting, 6 patients had improved strength, all had less pain, and 2 had less numbness. Six patients experienced neurologic decline an average of 2 years after shunt placement, 3 because of shunt failure, 2 from a new syrinx, and 1 from both shunt failure and new syrinx. Two of the 3 patients who underwent second shunt placements for a new syrinx had full neurologic recovery. Six patients said they would repeat the shunting procedure if necessary, 1 was uncertain, and 1 would not. CONCLUSION: Initial improvements noted after shunting provide long-lasting effects, even though many patients may need a second procedure. Less pain and improved strength are more significant than decreased numbness.  相似文献   
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Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease.  相似文献   
96.
Chronic neurobehavioural effects of toluene   总被引:5,自引:0,他引:5  
Neurobehavioural tests were undertaken by 30 female workers exposed to toluene and matched controls with low occupational exposure to toluene. The environmental air levels (TWA) of toluene was 88 ppm for the exposed workers and 13 ppm for the controls. The toluene in blood concentrations for the exposed workers was 1.25 mg/l and for the controls 0.16 mg/l. Statistically significant differences between workers exposed to toluene and controls in neurobehavioural tests measuring manual dexterity (grooved peg board), visual scanning (trail making, visual reproduction, Benton visual retention, and digit symbol), and verbal memory (digit span) were observed. Further, the performance at each of these tests was related to time weighted average exposure concentrations of air toluene. The workers exposed to toluene had no clinical symptoms or signs. The question arises as to whether these impairments in neurobehavioural tests are reversible or whether they could be a forerunner of more severe damage.  相似文献   
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BACKGROUND/AIMS: Production of nitric oxide (NO) in the liver is believed to be a critical factor for carbohydrate and energy metabolism in endotoxin shock. The present study focuses on the involvement of NO produced by inducible nitric oxide synthase (iNOS) in glycogen synthesis and energy metabolism stimulated by insulin.METHODS: Primary hepatocytes prepared from wild-type and iNOS knockout (iNOS(-/-)) mice were employed.RESULTS: Incubation of wild-type hepatocytes with a combination of cytokines (interleukin-1beta, tumor necrosis factor-alpha and interferon-gamma) and lipopolysaccharide (cytokines/LPS) inhibited insulin-stimulated glycogen synthesis and adenosine triphosphate (ATP) increase, and decreased the ketone body ratio (KBR) at 8-12 h, concomitant with expression of iNOS protein and NO production. While the glycogen synthesis was suppressed by cytokines/LPS, reduction of the ATP increase and a decrease in KBR by cytokines/LPS were not observed in iNOS(-/-) hepatocytes. Further, N(G)-monomethyl-L-arginine, a NOS inhibitor, reversed the inhibition of ATP increase and decrease in KBR by cytokines/LPS, but not the inhibition of glycogen synthesis. Conversely, addition of S-nitroso-N-acetylpenicillamine, a NO donor, inhibited the insulin-stimulated ATP increase synthesis in iNOS(-/-) hepatocytes, but not the insulin-stimulated glycogen synthesis.CONCLUSIONS: These results demonstrate that NO mediates the suppression of insulin-stimulated energy metabolism, but not glycogen synthesis, in cytokines/LPS-treated hepatocytes.  相似文献   
99.
Objectives. Monitoring arterial distensibility changes is important to understand the cardiovascular status of patient. Pulse transit time (PTT), which is an inverse equivalent of pulse wave velocity (PWV), has shown its potential in such studies. However, its methodological approach in using an electrocardiogram and a peripheral photoplethysmography (PPG) is limited due to the inclusion of pre-ejection period (PEP) in its computation. Previous studies have suggested the using the transit time difference between two peripheral measuring sites (PTT-D) instead. However, it requires two medical instruments and may not be efficient in terms of equipment utility, especially in prolonged clinical studies. Methods. Postural changes are known to cause complex haemodynamics adaptation and thereby affecting transit time measurements. A customised dual-channel PPG system based on discrete electronic devices was constructed to evaluate against conventional peripheral-based PTT. 10 healthy adults (7 male; mean age 27.0 yr) were recruited to assess the differences observed in PTT and PTT-D during two postural change test activities. Results. PTT-D derived from the customised PPG system registered 43.3± 5.6 ms and − 31.1± 3.8 msrelativechangesforthetworegulatedactivitieswhileconventionalPTTrecorded 43.6± 10.3 msand -31.0±m 6.5 msrespectively. Theformermayhavesimilarresultsbuthavesignificantlylowervariance (< EmphasisType =Italic p </Emphasis 0.05). Conclusions. Findings herein suggest that PTT-D derived from the customised PPG system shows potential. It can be used as an alternative to conventional peripheral-based PTT and possibly as a direct assessment of arterial distensibility or PWV variations as it does not include PEP in its time-related computations.  相似文献   
100.

Background

Monitoring unscheduled return visits to the Emergency Department (ED) is useful to identify medical errors.

Objective

To investigate the differences between unscheduled return visit admissions (URVA) and unscheduled return visit no admissions (URVNA) after ED discharge.

Methods

From January 1, 2008 to March 31, 2008, URVA and URVNA patients who returned within 3 days after ED discharge were enrolled in the study. We compared the clinical characteristics, underlying diseases, ED crowding indicators, staff experience at the patient's first visit, and several other risk factors. We used multivariate logistic regression to evaluate differences between the two groups and to identify predictors of admission from unscheduled return visits.

Results

The unscheduled return visit rate was 3.1%. Of the 413 patients included, 147 patients (36%) were admitted, and had a mortality rate of 4.1%. The most common reason for the return visit was an illness-based factor (47.9%). Compared to URVNA patients, unscheduled return visit admissions had higher prevalence rates for old age, non-ambulatory status, high-grade triage, and underlying diseases (e.g., malignancy, diabetes mellitus, hypertension, coronary artery disease, heart failure, and chronic obstructive pulmonary disease). The independent predictors for URVA were: age ≥ 65 years (adjusted odds ratio [OR] 2.2, 95% confidence interval [CI] 1.4–3.5); high-grade triage (adjusted OR 2.1, 95% CI 1.3–3.2); and doctor-based factors (adjusted OR 3.5, 95% CI 2.0–6.1). More advanced staff experience (p = 0.490) and ED crowding were not significant predictors (p = 0.498 for whole-day number of patients, p = 0.095 for whole-shift number of patients).

Conclusion

Old age, high-grade triage, and doctor-based factors were found to be significant predictors for URVA, whereas advanced staff experience and ED crowding were not.  相似文献   
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