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Immature platelets—also termed reticulated platelets (RP)—are platelets newly released into the circulation, and have been associated with a variety of pathological thrombotic events. They can be assessed by flow cytometry after staining with thiazole orange (TO) or by using a module added to a fully automated analyzer that is currently in wide clinical use and expressed as a fraction of the total platelet count (IPF). We sought to assess the correlation and agreement between these two methods. IPF was measured using Sysmex XE 2100—and at the same time point- we used TO staining and flow cytometry to measure RP levels. Two different gates were used for the flow cytometry method, 1 and 0.5 %. Measurements from the automated analyzer were then compared separately to measurements performed using each gate. Agreement between methods was assessed using Bland–Altman method. Pearson’s correlation coefficient was also calculated. 129 subjects were enrolled and stratified into 5 groups: (1) Healthy subjects, (2) End stage renal disease, (3) Chronic stable coronary artery disease, (4) Post Coronary artery bypass surgery, (5) Peripheral thrombocytopenia. Median IPF levels were increased for patients in groups 2, 3, 4 and 5 (4.0, 4.7, 4.3, and 8.3 % respectively) compared to healthy subjects (2.5 %) p = 0.0001. Although the observed correlation between the two methods tended to be good in patients with high IPF values (i.e., group 5), the overall observed correlation was poor (Pearson’s correlation coefficient r = 0.27). Furthermore, there was poor agreement between the two methods in all groups. Despite the good correlation that was observed between the two methods at higher IPF values, the lack of agreement was significant.  相似文献   
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Barrett's esophagus (BE) is defined as abnormal specialized columnar metaplasia with intestinalization in place of the normal squamous esophageal epithelium. Gastroesophageal reflux disease is a known risk factor for BE; nonetheless BE is also detected in asymptomatic individuals. Other risk factors for BE include smoking, male gender, age over 50 and obesity. Patients diagnosed with BE (without dysplasia) are recommended to undergo endoscopic surveillance every 3-5 years. Advances in imaging techniques (such as narrow band imaging, autofluorescence imaging and confocal laser endomicroscopy) have the potential to improve the detection of dysplasia and early cancer, thus making surveillance a more cost-effective endeavor. Patients with high grade dysplasia (HGD) and early cancer have a high rate of progression to invasive adenocarcinoma and traditionally these patients were treated with esophagectomy. The rapid advancement of endoscopic therapeutic techniques along with a low risk of complications have made endoscopic therapy an acceptable alternative to an esophagectomy in patients with HGD and early cancer. Several endoscopic treatment techniques such as endoscopic mucosal resection, multipolar electrocoagulation, photodynamic therapy, argon plasma coagulation, cryotherapy, and radiofrequency ablation have been studied for endoscopic treatment.  相似文献   
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BACKGROUND: Trichodiscomas are rare hamartomas of the dermal portion of the hair disc, a specialized component of the perifollicular mesenchyme. They are usually found as asymptomatic multiple skin-colored papules on the face and extremities and may have an autosomal dominant inheritance pattern. However, a solitary variant has been described. CASE REPORT: A 78-year-old woman presented with a single, non-pigmented, firm papule on the left tip of the nose, measuring 3.5 mm in diameter. RESULTS: The histological examination revealed the previously described features of a trichodiscoma. The immunohistochemical analysis showed strong immunoreactivity for CD34 in the spindle cell component. Spindle cells were negative for S-100, HMB-45, Melan-A, EMA, neurofilament, desmin, and Factor XIIIa by immunohistochemistry. CONCLUSIONS: We report strong reactivity for CD34 in the spindle cell component of a trichodiscoma. We suggest that this lesion be considered in the differential diagnosis of any CD34+ dermal spindle cell proliferation, in which an adjacent epithelial component cannot be entirely excluded.  相似文献   
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BACKGROUND: Patients with Barrett's esophagus (BE) and high-grade dysplasia (HGD) are at a high risk for developing esophageal adenocarcinoma. However, the reported rate of cancer development in patients with HGD who were undergoing surveillance has varied among published studies. OBJECTIVE: To determine an overall precise estimate of cancer incidence in patients with HGD who were undergoing surveillance endoscopy. DESIGN: Systematic review and meta-analysis. METHODS: We conducted a systematic search of the published literature and selected original articles that examined patients with histologically proven BE and HGD, patients who had not undergone endoscopic ablation or surgical therapy, patients with 6 months' follow-up, no esophageal cancer at the time of enrollment or within 6 months, and studies in which follow-up was reported in person-time. Two investigators independently conducted the search and abstraction. MAIN OUTCOME MEASUREMENT: The weighted mean event rate was calculated and expressed as the weighted incidence rate, and its CIs were calculated. RESULTS: The search yielded 4 articles that met the inclusion criteria, and these were analyzed. A total of 236 patients with HGD were followed for 1241 patient-years, and esophageal adenocarcinoma was reported in 69 patients, providing a crude incidence rate of 5.57 per 100 patient-years. The weighted incidence rate was 6.58 per 100 patient-years (95% CI, 4.97-8.19). LIMITATIONS: A small number of studies that met inclusion criteria. CONCLUSIONS: In patients with BE and with HGD who were undergoing surveillance, esophageal adenocarcinoma develops in approximately 6 per 100 patient-years during the first few years of follow-up. These data may better inform physicians and patients in management decisions.  相似文献   
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A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes.  相似文献   
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Arrangement of artificial teeth in a bilaterally symmetrical fashion with proper inclinations of teeth had been a challenging task for beginners. A variety of tools and guiding equipment have been developed to help students to learn teeth arrangement. Unfortunately, those tools were either costly or unsuitable for use with mean value articulators. This article attempts to introduce a simplified clinometer which can be attached to mean value articulator and can be used as a guide to arrange teeth in a bilaterally symmetrical manner by the undergraduates in both clinical and preclinical set-up. CLINICAL SIGNIFICANCE: Training of the future dentists in sound esthetic principles in a preclinical environment, using this device, will increase the final clinical efficacy of their work. AIM: The aim of this article is to provide a simple but effective device to undergraduate students to help them learn teeth arrangement easily and systematically.  相似文献   
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