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11.
The Japanese criteria for diagnosing Sjögren's syndrome (SS) were revised in 1999, and consist of four major areas: histopathology, oral examination, ocular examination, and serological examination. A diagnosis of SS can be made when the patient meets at least two of these four criteria. This report describes how the revised Japanese criteria were established. After the publication of the revised Japanese criteria (1999), a research study which focused on evaluating its availability and validity was carried out in 2001 using funds from Grant-in-Aids for Scientific Research supported by the Japan Society for the Promotion of Science. The availability of the revised criteria was investigated by a questionnaire study through the Japanese Medical Society for Sjögren's Syndrome, and the use of the revised criteria for diagnosing SS in these medical facilities was found to be 76%. To evaluate the validity of the revised criteria, the records of 900 patients, including SS patients and non-SS controls, from 54 clinical centers were registered and analyzed to calculate the accuracy of the criteria. The revised Japanese criteria were found to have 96.0% sensitivity, 90.5% specificity, and 94.5% accuracy for diagnosing SS.  相似文献   
12.
ObjectivesTo measure central macular thickness in Jordanian patients with sickle cell disease who did not have retinopathy and compare the findings with age- and sex-matched controls using spectral domain optical coherence tomography (SDOCT).MethodsIn this cross-sectional study, participants underwent visual acuity testing, slit-lamp bio-microscopy, dilated ophthalmoscopy, and SDOCT imaging to measure central macular thickness. Macular quadrant measurements and thickness difference indexes (TDIs) were compared between groups.ResultsTwenty eyes with sickle cell disease and 20 control eyes were enrolled. The median visual acuity in both groups was 20/20. The mean macular thickness was significantly lower in eyes with sickle cell disease than in matched controls (mean difference, 22.15 ± 6.44 µm). Peripheral quadrants were all significantly thinner in eyes with sickle cell disease, especially in superior and temporal quadrants. TDIs were lower in eyes with sickle cell disease than in control eyes.ConclusionsEyes with sickle cell disease that had no clinical evidence of retinopathy exhibited significantly lower central macular thickness in all quadrants, compared with eyes in age- and sex-matched controls. SDOCT is a non-invasive imaging modality that can detect preclinical changes in eyes with sickle cell disease and can be used to screen and monitor the disease process.  相似文献   
13.
OBJECTIVES: Angiotensin II suppression leads to impaired vascular relaxation in normotensive animals on a high-salt diet. The goal of this study was to determine whether normal vascular reactivity could be restored by transferring the chromosomal region carrying the Dahl salt-resistant (R) renin gene into the Dahl salt-sensitive (SS) genetic background in a strain of renin congenic rats (RGRR). METHODS: Male RGRR and SS rats were fed low-salt (0.4%) and high-salt (4%) diets for 4 weeks. The responses of cremaster muscle arterioles to acetylcholine (ACh), sodium nitroprusside (SNP), and elevated PO2 were assessed using video microscopy. RESULTS: ACh-induced dilation was significantly enhanced in RGRR on a high-salt diet compared to SS rats, while dilation to the NO donor SNP was similar in both strains. A high-salt diet significantly enhanced arteriolar constriction in response to elevated PO2, in both SS and RGRR rats. CONCLUSIONS: These data suggest that transfer of the chromosomal region containing the renin gene is crucial in the recovery of ACh-induced dilation of arterioles in RGRR rats vs. SS rats, and that factors in the SS genetic background contribute to an enhanced sensitivity to elevated PO2, independent of genes on chromosome 13.  相似文献   
14.

Background

The functional SYNTAX score (FSS) has been shown to improve the discrimination for major adverse cardiac events compared with the anatomic SYNTAX score (SS) while reducing interobserver variability. However, evidence supporting the noninvasive FSS in patients with multivessel coronary artery disease (CAD) is scarce.

Objectives

The purpose of this study was to assess the feasibility of and validate the noninvasive FSS derived from coronary computed tomography angiography (CTA) with fractional flow reserve (FFRCT) in patients with 3-vessel CAD.

Methods

The CTA-SS was calculated in patients with 3-vessel CAD included in the SYNTAX II (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery II) study. The noninvasive FSS was determined by including only ischemia-producing lesions (FFRCT ≤0.80). SS derived from different imaging modalities were compared using the Bland-Altman and Passing-Bablok method, and the agreement on the SS tertiles was investigated with Cohen’s Kappa. The risk reclassification was compared between the noninvasive and invasive physiological assessment, and the diagnostic accuracy of FFRCT was assessed by the area under the receiver-operating characteristic curve using instantaneous wave-free ratio as a reference.

Results

The CTA-SS was feasible in 86% of patients (66 of 77), whereas the noninvasive FSS was feasible in 80% (53 of 66). The anatomic SS was overestimated by CTA compared with conventional angiography (27.6 ± 6.4 vs. 25.3 ± 6.9; p < 0.0001) whereas the calculation of the FSS yielded similar results between the noninvasive and invasive imaging modalities (21.6 ± 7.8 vs. 21.2 ± 8.8; p = 0.589). The noninvasive FSS reclassified 30% of patients from the high- and intermediate-SS tertiles to the low-risk tertile, whereas invasive FSS reclassified 23% of patients from the high- and intermediate-SS tertiles to the low-risk tertile. The agreement on the classic SS tertiles based on Kappa statistics was slight for the anatomic SS (Kappa = 0.19) and fair for the FSS (Kappa = 0.32). The diagnostic accuracy of FFRCT to detect functional significant stenosis based on an instantaneous wave-free ratio ≤0.89 revealed an area under the receiver-operating characteristics curve of 0.85 (95% CI: 0.79 to 0.90) with a sensitivity of 95% (95% CI: 89% to 98%), specificity of 61% (95% CI: 48% to 73%), positive predictive value of 81% (95% CI: 76% to 86%), and negative predictive value of 87% (95% CI: 74% to 94%).

Conclusions

Calculation of the noninvasive FSS is feasible and yielded similar results to those obtained with invasive pressure-wire assessment. The agreement on the SYNTAX score tertile classification improved with the inclusion of the functional component from slight to fair agreement. FFRCT has good accuracy in detecting functionally significant lesions in patients with 3-vessel CAD. (A Trial to Evaluate a New Strategy in the Functional Assessment of 3-Vessel Disease Using SYNTAX II Score in Patients Treated With PCI; NCT02015832)  相似文献   
15.
ObjectivesThis study sought to evaluate the long-term prognostic capacity of the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score II (SS-II) and compare it with other risk scores among patients undergoing left main percutaneous coronary intervention (LM-PCI).BackgroundRecently, the SS-II was developed in an attempt to individualize and help the decision-making process between PCI and coronary artery bypass graft (CABG) surgery in the management of complex coronary artery disease (CAD). However, there is a paucity of data regarding the utility of SS-II in patients undergoing LM-PCI.MethodsData from 1,528 consecutive patients from a single center undergoing unprotected LM-PCI were prospectively collected. The SS-II and other scores were then derived using patients’ baseline clinical characteristics. Patients were stratified according to tertiles of SS-II for PCI: SS-II ≤21 (n = 508), SS-II >21 and ≤28 (n = 480), and >28 (n = 540). Predictive capability for long-term mortality was compared between angiographic scores and scores combining both angiographic and clinical variables.ResultsAt a mean follow-up of 4.4 years, mortality in the first, second, and third SS-II tertiles was 1.8%, 3.5%, and 9.4%, respectively (p < 0.0001). Multivariate analysis showed SS-II to be a strong independent predictor of mortality (hazard ratio: 1.76, 95% confidence interval: 1.10 to 2.82; p = 0.02) after LM-PCI. When compared with the angiographic SS, scores combining both clinical and angiographic variables, such as the SS-II, were superior in terms of long-term prognostication.ConclusionsResults of this large series of consecutive patients who underwent unprotected LM-PCI suggested that the SS-II has better long-term prognostic power in terms of mortality compared with the original purely angiographic SS.  相似文献   
16.
Soft tissue sarcoma is the most common malignant cardiac tumor. The chief modes of presentation are embolization, obstruction, and arrhythmogenesis. We describe an unusual case of a 27-year-old man who presented with nausea and dyspnea on exertion. Transthoracic echocardiography and computed tomography revealed a huge mass in the right heart that extended through the inferior vena cava and right renal vein to the right kidney. The cardiac mass was resected, and an immunohistochemical analysis revealed it to be a TLE1-positive synovial sarcoma. After surgery, the patient received serial adjuvant chemotherapy. We herein describe the case with a brief review.  相似文献   
17.
Although poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has good electrical conductivity and high transparency in most applications, its usage in stretchable applications is limited because of its rigidity, reduced conductivity after elongation, and poor environmental stability. This study addresses these issues by incorporating the soft and relatively hydrophobic moiety poly(ethylene glycol) methacrylate (PEGMA). By incorporating PEGMA randomly in the rigid PSS chain, a soft and hydrophobic copolymer P(SSco‐PEGMA) is obtained. The conducting P(SSco‐PEGMA)‐based polymer‐coated PET film exhibits good resistance even after 400% elongation. In addition, PEDOT:P(SSco‐PEGMA) has better environmental stability than PEDOT:PSS because of the presence of the relatively hydrophobic PEGMA moiety in the chain. Moreover, the potential applicability of the synthesized flexible and stretchable electronic material as a stretchable matrix is established, which includes inorganic conductors (AgNW). When this material is stretched, it can be applied as a conductive interconnector to maintain the electrical pathway, instead of the other insulating matrices.  相似文献   
18.
刘淑娥 《河北医学》2007,13(12):1217-1219
目的:从胃肠激素水平探讨健脾中药儿食儿食健宝颗粒治疗小儿厌食症的作用机制。方法:用饮食不当法复制幼龄厌食症大鼠模型,通过观察肠内P物质(SP)、血管活性肠肽(VIP)、生长抑制素(SS)水平的变化,以及胃肠病理形态学改变,观察儿食健宝颗粒的作用。结果:儿食健宝颗粒可以改善厌食症大鼠SP、VIP、SS水平变化及胃肠粘膜病理形态。结论:儿食健宝颗粒可改善厌食症大鼠胃肠黏膜的病理形态学改变,并对SP、VIP、SS具有调节与平衡作用。  相似文献   
19.
《针刺研究》2009,34(3)
目的:观察电针对抑郁大鼠行为学、海马生长抑素(somatostatin,SS)及SS mRNA表达的影响,探讨电针治疗抑郁症的可能机制。方法:30只健康Wistar大鼠,随机分为正常组、模型组和电针组,每组10只。慢性应激法刺激造抑郁大鼠模型,电针"百会"三阴交",每日1次,每次20 min,连续14 d。使用开野试验和糖水试验检测大鼠行为学变化,使用免疫组化法和逆转录多聚酶链反应法测定SSSS mRNA的表达。结果:造模后模型组大鼠水平和垂直运动次数、糖水摄入量与正常组比较均降低(P<0.01),治疗后电针组的水平、垂直运动次数较治疗前及模型组均有升高(P<0.01)。模型组与正常组相比,SSSS mRNA表达均降低(P<0.05);电针组与模型组比较,SSSS mRNA表达均升高(P<0.05)。结论:电针可明显改善抑郁大鼠行为学,提高抑郁大鼠海马SSSS mRNA的表达,电针的抗抑郁作用可能与之有关。  相似文献   
20.
The use of metal additive manufacturing (AM) has strongly increased in the industry during the last years. More specifically, selective laser melting (SLM) is one of the most used techniques due to its numerous advantages compared to conventional processing methods. The purpose of this study is to investigate the effects of process parameters on the microstructural and corrosion properties of the additively manufactured AISI 316L stainless steel. Porosity, surface roughness, hardness, and grain size were studied for specimens produced with energy densities ranging from 51.17 to 173.91 J/mm3 that resulted from different combinations of processing parameters. Using experimental results and applying the Taguchi model, 99.38 J/mm3 was determined as the optimal energy density needed to produce samples with almost no porosity. The following analysis of variance ANOVA confirmed the scanning speed as the most influential factor in reducing the porosity percentage, which had a 74.9% contribution, followed by the position along the building direction with 22.8%, and finally, the laser energy with 2.3%. The influence on corrosion resistance was obtained by performing cyclic potentiodynamic polarization tests (CPP) in a 3.5 wt % NaCl solution at room temperature for different energy densities and positions (Z axis). The corrosion properties of the AM samples were studied and compared to those obtained from the traditionally manufactured samples. The corrosion resistance of the samples worsened with the increase in the percentage of porosity. The process parameters have consequently been optimized and the database has been extended to improve the quality of the AM-produced parts in which microstructural heterogeneities were observed along the building direction.  相似文献   
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