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81.
An early diagnosis of colorectal polyp can be achieved through screening and surveillance programs. In the past few years, advances in endoscopic imaging of the colorectal mucosa have been extensively developed, leading to an increased detection of pre-malignant lesions as well as low-grade and nonneoplastic polyps. In order to reduce the overall cost of care with minimal impact on the quality of care in colorectal cancer prevention, the "diagnosis and discard" strategy has been considered. High-definition, narrow band imaging and confocal endomicroscopy are image enhancement technologies that have been widely studied lately. The studies from Pasha et al. and Kuiper et al. demonstrate the limitations of these new advanced imaging technologies and that further studies should continue to be developed. 相似文献
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Vivian Bradaschia-Correa Inmaculada Casado-Gomez Mariana Matheus Moreira Lorraine Braga Ferreira Victor E. Arana-Chavez 《Archives of oral biology》2013
Introduction
During root formation, Smad-4 plays a key role during the epithelial–mesenchymal interactions and the Hertwig's epithelial root sheath (HERS) apical proliferation. The root formation and eruption of rat molars is impeded by alendronate treatment due to the inhibition of bone resortion by this drug. The present study aimed to examine the structures affected in the developing root and immunodetect the presence of Smad-4 in rats treated with alendronate.Methods
Newborn Wistar rats were daily injected 2.5 mg/kg alendronate (ALN) during 9, 12 and 30 days. The controls (CON) were injected with saline. The maxillae were fixed and embedded in paraffin or Spurr resin. Paraffin sections were incubated in Smad-4 antibody that was labelled with DAB. The ultrathin sections were examined in a transmission electron microscope.Results
In ALN, a short portion of root dentine was formed; the epithelial diaphragm (ED) and the dental follicle (DF) were disorganized by the contact of bone trabeculae. The (CON) molar roots developed normally. Smad-4 labelling was detected in the cytoplasm of fibroblasts and cementoblasts adjacent to the cementum in CON; in ALN group, few ED cells presented weak immunolabelling. Ultrastructurally, the ED and DF appeared disrupted due to the presence of thin bone trabeculae between its cells. It resulted in the lack of apical proliferation of HERS and, consequently, arrest of root formation.Conclusion
The immunodetection of Smad-4 in the DF cells of ALN specimens indicates that the signalling for the differentiation of these cells into cementum-forming fibroblasts and cementoblasts occurs, despite the impairment of root elongation. 相似文献84.
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A sensitive and specific sandwich ELISA was developed for the diagnosis of Glanzmann’s thrombasthenia (GT) and the heterozygote
carriers of the disease using whole blood platelets. The assay used anti-CD36 antibody to capture platelets from platelet-rich
plasma which was subsequently treated with a bioengineered disintegrin/alkaline phosphatase hybrid protein specific for GP
IIb/IIIa. The test allows large number of samples to be typed and can also be used on stored samples. The assay correctly
diagnosed 40 normal healthy individuals, 10 GT cases, 10 heterozygotes, 3 Bernard–Soulier syndrome cases and 2 type 3 GT cases.
ELISA plates were stable at room temperature up to 3 weeks without any loss of activity. This novel and simple test can be
widely used for heterozygote detection besides diagnosing GT cases without using a sophisticated flow cytometer or a platelet
aggregometer and has wide applicability in countries like India where many of these cases remain undiagnosed due to the lack
of diagnostic facilities. 相似文献
86.
Aim To examine the effectiveness of a stage‐matched smoking cessation counselling intervention for smokers who had cardiac diseases. Methods A total of 1860 Chinese cardiac patients who smoked at least one cigarette in the past 7 days and aged 18 years or above recruited from cardiac out‐patient clinics in Hong Kong hospitals were allocated randomly to an intervention group or control group. The intervention group (n = 938) received counselling matched with their stage of readiness to quit by trained counsellors at baseline, 1 week and 1 month. The control group (n = 922) received brief counselling on healthy diet at baseline. The primary outcomes were self‐reported 7‐day and 30‐day point prevalence (PP) of tobacco abstinence at 12 months after baseline. The secondary outcome measures included biochemically validated abstinence at 12‐month follow‐up, self‐reported 7‐day and 30‐day PP abstinence and reduction of cigarette consumption by 50% at 3 and 6 months. Results By intention‐to‐treat analysis, the intervention and control groups showed no significant difference in self‐reported 7‐day PP abstinence (intervention: 26.5% versus control: 25.5%; P = 0.60) and 30‐day PP (intervention: 25.4% versus control: 24.2%; P = 0.55), biochemically validated abstinence (intervention: 6.6% versus control: 4.9%; P = 0.14) and overall quit attempts of least 24 hours (intervention: 40.3% versus control: 34.3%; P = 0.007) at the 12‐month follow‐up, adjusted for the baseline stage of readiness to quit smoking. Conclusions An intervention, based on the Stages of Change model, to promote smoking cessation in cardiac patients in China failed to find any long‐term benefit. 相似文献
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Aimee L. Smith Deborah R. Karp Vivian C. Aguilar G. Willy Davila 《International urogynecology journal》2013,24(6):963-968