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巢蛋白(Nestin)在胃肠道间质瘤组织中的表达及其临床意义   总被引:11,自引:0,他引:11  
目的 通过检测胃肠道间质瘤 (GIST )组织中巢蛋白 (nestin)的表达 ,探讨nestin在GIST的诊断、鉴别诊断及起源中的意义。方法 应用免疫组织化学技术EnVision微波二步法 ,检测 94例GIST (良性 44例 ,恶性 5 0例 )组织中nestin蛋白的表达 ,并与平滑肌瘤和平滑肌肉瘤进行对照研究。结果 GIST组织中nestin的阳性表达率为 95 .7% ( 90 /94) ,良、恶性组nestin的阳性率分别为 97.7% ( 4 3 /4 4)、94.0 % ( 4 7/5 0 )。 2组的表达水平无显著性差异 (P >0 .0 5 )。平滑肌瘤和平滑肌肉瘤nestin表达均阴性。结论 Nestin作为胃肠道间质瘤的 1种特异而敏感的新标志物 ,对GIST的诊断及鉴别诊断有重要意义 ,但不能作为GIST分化程度的指标 ,同时提示GIST可能起源于向卡哈尔细胞 (ICC )表型分化的干细胞。  相似文献   
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Objective

Determine agreement between self-reported dose and dose reflected in administrative records of outpatient physical, occupational, and speech therapies at 6 and 12 months after severe traumatic brain injury (TBI), for the purpose of examining accuracy and predictors of accuracy of self-reported health care utilization in this population.

Design

Secondary analysis of survey used in a larger study; participants were queried about therapy doses using a structured interview, either alone or assisted by relatives if they so chose, with responses compared to administrative records.

Setting

Rehabilitation center providing outpatient TBI therapies.

Participants

Sixty-five people with severe TBI living in the community provided 6-month data (N=65); 54 provided 12-month data.

Interventions

Not applicable.

Main Outcome Measures

Degree of agreement with administrative records of scheduled and billed therapy appointments, measured using intraclass correlation coefficients (ICCs), with linear regression used to predict accuracy from demographic variables and cognitive status.

Results

ICCs were in the moderate range at 6 months, but were more variable, with some in the poor range, at 12 months. Agreement was higher for scheduled than for billed (attended) appointments. Assisted and unassisted patients provided comparable agreement with records. No demographic factors were associated with accuracy, but lower cognitive FIM scores, as hypothesized, tended to predict lower agreement at 6 months.

Conclusions

People with severe TBI can provide reasonable estimates of commonly prescribed outpatient therapy doses at 6 months postinjury. Accuracy may be improved by inviting patients to request assistance from relatives and by asking them to consider attended (vs scheduled) sessions.  相似文献   
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目的探讨白萝卜提取物(raphanus sativus 1 extract,Ecr)通过Cajal间质细胞促胃肠动力作用机制。方法40只SD大鼠随机分为A(Ecr)组、B(0.9%氯化钠对照)组分别灌服等体积Ecr和0.9%氯化钠,1h后用双重免疫荧光组织化学标记的方法观察胃电起搏区Cajal间质细胞(interstitial cells of Cajal,ICC)与P物质(SP)阳性神经及产物表达的变化。结果肌间神经丛中ICC与SP阳性神经呈网络样分布,二者紧密毗邻;肌间神经丛及肌层内与ICC结合的SP阳性神经产物表达明显增加(P〈0.01)。结论白萝卜提取物的促胃肠动力作用可能与胃体ICC上结合的SP阳性神经产物表达增高有密切关系。  相似文献   
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Objective

To document in adults affected by autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) the intra- and interrater reliability, standard error of measurement, agreement, minimal detectable change, and construct validity of the 9-Hole Peg Test (NHPT), the Standardized Finger-to-Nose Test (SFNT), and grip strength.

Design

Metrologic study.

Setting

Neuromuscular rehabilitation clinic.

Participants

Genetically confirmed adult patients with ARSACS (N=42; 21 women; mean age, 38.6y).

Interventions

Not applicable.

Main Outcome Measures

Intra- and interrater reliability was determined using the intraclass correlation coefficient (ICC). Construct validity was determined by assessing the capacity of the NHPT, the SFNT, and grip strength to distinguish between participants based on sex, mobility stages, and age groups, and on performance on the Archimedes spiral and fast alternating hand movements tests.

Results

All 3 tests have shown excellent reliability (ICC=.90–.98). However, the limit of agreement was influenced by the participant’s performance on the NHPT, and the minimal detectable change was very different for both hands (right=9.7 vs left=28.0). Construct validity was confirmed for the SFNT and NHPT, but it was not demonstrated for grip strength.

Conclusions

Given the metrologic properties assessed in this study, the SFNT is an excellent measure to assess upper limb coordination, whereas the NHPT must be used with caution. The grip strength is reliable but does not seem to reflect disease severity.  相似文献   
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BACKGROUND & AIMS: We established the concept that transient enteric infection may lead to persistent gut dysfunction, evident in vitro, in nematode-infected mice. The present study determined whether gut dysfunction in this model involves motor and sensory changes reminiscent of changes found in patients with postinfective irritable bowel syndrome (PI-IBS) and investigated underlying mechanisms. METHODS: Mice infected up to 70 days previously with Trichinella spiralis (Tsp) underwent videofluoroscopy with image analysis to assess upper gastrointestinal motility. Pseudoaffective responses to colorectal distention (CRD) were assessed using a barostat and validated by single fiber recordings from spinal nerves during CRD. Tissues were examined at different time points for histology, immunohistochemistry, and cytokine analysis. Some mice received dexamethasone intraperitoneally on days 23-25 PI or Tsp antigen orally on days 29, 43, and 57 PI. RESULTS: From day 28 PI, no discernible inflammation was present in the gut. Frequency and propagation velocity of intestinal contractions decreased, and retroperistalsis increased at days 28 to 42 PI. CRD induced an allodynic and hyperalgesic response in PI mice, which was accompanied by increased single unit discharge. Gavage of Tsp antigen induced T-cell responses and sustained gut dysfunction for 70 days PI. Administration of dexamethasone postinfection normalized dysmotility and visceral hyperalgesia. CONCLUSIONS: Long-lasting gut dysmotility and hyperalgesia develop in mice after transient intestinal inflammation. These changes are maintained by luminal exposure to antigen and reversed by corticosteroid treatment. The findings prompt consideration of this as a model of PI-IBS.  相似文献   
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Indirect techniques of predicting hand grip force are fundamental to develop hand control systems for assistive devices. The purpose of this study was to determine the reliability of 3D position of forearm surface at different isometric hand grip forces. Three-dimensional motion analysis was used to measure displacement of 24 discrete and standardized surface markers placed on forearm in 20 healthy participants. The relative displacements were measured for isometric grip forces at 0%, 5%, 20% 50% and 80% of maximum voluntary contraction (MVC). Intraclass correlation coefficient (ICC) for relative radial displacement (RRD) of each marker was calculated. Averaged single measure ICC of 24 markers at five grip forces was 0.61; while the highest averaged single measure ICC (0.80) for all markers was achieved at 80% of MVC and the lowest (0.47) at 0% of MVC. The average measure ICC for each grip force across the 24 markers also increased with grip force from 0.80 at 0% of MVC to the maximum of 0.95 at 80% of MVC. In conclusion, RRD showed moderate and high ICCs for single and average measures respectively. Overall, this study suggests that the reliable dimensional changes of 3D positions of forearm surface might be considered as an indirect and non-invasive method to predict hand grip force in future.  相似文献   
9.

Background

Atherosclerotic plaque characteristics may affect downstream myocardial perfusion, as well as coronary lesion severity.

Objectives

This study sought to evaluate the association between quantitative plaque burden and plaque morphology obtained using coronary computed tomography angiography (CTA) and quantitative myocardial perfusion obtained using [15O]H2O positron emission tomography (PET), as well as fractional flow reserve (FFR) derived invasively.

Methods

Two hundred eight patients (63% men; age 58 ± 8.7 years) with suspected coronary artery disease were prospectively included. All patients underwent 256-slice coronary CTA, [15O]H2O PET, and invasive FFR measurements. Coronary CTA-derived plaque burden and morphology were assessed using commercially available software and compared with PET perfusion and FFR.

Results

Atherosclerotic plaques were present in 179 patients (86%) and 415 of 610 (68%) evaluable coronary arteries. On a per-vessel basis, traditional coronary plaque burden indexes, such as plaque length and volume, minimal lumen area, and stenosis percentage, were significantly associated with impaired hyperemic myocardial blood flow (MBF) and FFR. In addition, morphological features, such as partially calcified plaques, positive remodeling (PR), and low attenuation plaque, displayed a negative impact on hyperemic MBF and FFR. Multivariable analysis revealed that the morphological feature of PR was independently related to impaired hyperemic MBF as well as an unfavorable FFR (p = 0.004 and p = 0.007, respectively), next to stenosis percentage (p = 0.001 and p < 0.001, respectively) and noncalcified plaque volume (p < 0.001 and p = 0.010, respectively).

Conclusions

PR and noncalcified plaque volume are associated with detrimental downstream hyperemic myocardial perfusion and FFR, independent of lesion severity.  相似文献   
10.
ObjectivesThe purpose of this study was to compare myocardial blood flow (MBF) and myocardial flow reserve (MFR) estimates from rubidium-82 positron emission tomography (82Rb PET) data using 10 software packages (SPs) based on 8 tracer kinetic models.BackgroundIt is unknown how MBF and MFR values from existing SPs agree for 82Rb PET.MethodsRest and stress 82Rb PET scans of 48 patients with suspected or known coronary artery disease were analyzed in 10 centers. Each center used 1 of 10 SPs to analyze global and regional MBF using the different kinetic models implemented. Values were considered to agree if they simultaneously had an intraclass correlation coefficient >0.75 and a difference <20% of the median across all programs.ResultsThe most common model evaluated was the Ottawa Heart Institute 1-tissue compartment model (OHI-1-TCM). MBF values from 7 of 8 SPs implementing this model agreed best. Values from 2 other models (alternative 1-TCM and Axially distributed) also agreed well, with occasional differences. The MBF results from other models (e.g., 2-TCM and retention) were less in agreement with values from OHI-1-TCM.ConclusionsSPs using the most common kinetic model—OHI-1-TCM—provided consistent results in measuring global and regional MBF values, suggesting that they may be used interchangeably to process data acquired with a common imaging protocol.  相似文献   
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