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51.
Comparison of ethanol versus formalin fixation on preservation of histology and RNA in laser capture microdissected brain tissues 总被引:1,自引:0,他引:1
Su JM Perlaky L Li XN Leung HC Antalffy B Armstrong D Lau CC 《Brain pathology (Zurich, Switzerland)》2004,14(2):175-182
Although RNA can be retrieved from formalin-fixed, paraffin-embedded (FFPE) tissues, the yield is low, and the RNA is fragmented. Recent advances in gene expression profiling underscore the importance of identifying a fixative that preserves histology and mRNA. We demonstrated that, for immersion fixation of brains, 70% ethanol is superior to formalin for mRNA preservation. RNA yield from ethanol-fixed tissues was 70% of the yield from fresh frozen specimens, but only a negligible quantity was recovered from formalin-fixed tissues. RNA from ethanol-fixed brains showed integrity comparable to RNA from fresh frozen tissues, and RT-PCR using RNA from ethanol-fixed tissues was consistently successful. RNA from FFPE tissues composed of low-molecular weight fragments, and their use in RT-PCR failed repeatedly. The yield and quality of RNA from ethanol-fixed brains were unaffected after immersion at 4 degrees C for 2 weeks. In a blinded comparison to FFPE tissues, ethanol-fixed specimens were judged to show comparable histology and superior immunostaining. After laser capture microdissection (LCM), we failed to recover mRNA from FFPE tissues but retrieved mRNA from ethanol-fixed tissues for RT-PCR and cDNA microarray analysis. We conclude that 70% ethanol preserves RNA integrity and is suitable for expression profiling of brain tissues by LCM and cDNA microarray. 相似文献
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Summary The results obtained from electron microscopy, adsorbed and internalised virus assays and immunofluorescence studies supported that the most likely mode of entry of Kunjin virus into Vero cells was by receptor-mediated endocytosis. This was deduced indirectly from the time sequence of events that occurred. Electron microscopy revealed that endocytosis of the virus through coated vesicles had occurred. The adsorbed and internalised virus assay and immunofluorescence studies showed that there were two factors being recycled during endocytosis: the receptor for the virus and clathrin, the protein found on coated pits and vesicles. The study showed that clathrin was recycled first, followed by the receptor. 相似文献
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In a controlled clinical trial-manual vs. stapler anastomosis in rectal surgery-it was found that both suture techniques per se made no difference in the function of anal continence. The anal pressures at rest and sphincter contraction remained unchanged. A linear reduction of functional reservoir of the "neorectum" could be shown, which depended on the level and healing of the anastomosis. An anastomosis level at 6 cm from anocutaneous line is important for functional reasons. Anastomoses above this level do not cause any consequences for anal continence. Anastomoses below this level result in a reduced functional reservoir for at least 6 months. Within this period a decrease in anal continence is possible, especially in cases of disturbed healing of the anastomosis. 相似文献
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Anselmi Laura Lau Yiu-Shing Sutton Matt Everton Anna Shaw Rob Lorrimer Stephen 《The European journal of health economics》2022,23(1):133-151
The European Journal of Health Economics - Risk-adjustment models are used to predict the cost of care for patients based on their observable characteristics, and to derive efficient and equitable... 相似文献
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Pathogenesis of severe acute respiratory syndrome 总被引:8,自引:0,他引:8
Severe acute respiratory syndrome (SARS) is a zoonotic infectious disease caused by a novel coronavirus (CoV). The tissue tropism of SARS-CoV includes not only the lung, but also the gastrointestinal tract, kidney and liver. Angiotensin-converting enzyme 2 (ACE2), the C-type lectin CD209L (also known L-SIGN), and DC-SIGN bind SARS-CoV, but ACE2 appears to be the key functional receptor for the virus. There is a prominent innate immune response to SARS-CoV infection, including acute-phase proteins, chemokines, inflammatory cytokines and C-type lectins such as mannose-binding lectin, which plays a protective role against SARS. By contrast there may be a lack of type 1 interferon response. Moreover, lymphopenia with decreased numbers of CD4+ and CD8+ T cells is common during the acute phase. Convalescent patients have IgG-class neutralizing antibodies that recognize amino acids 441-700 of the spike protein (S protein) as the major epitope. 相似文献
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A previous study found that Iliad, a diagnostic expert system, detects diagnostic errors missed by peer review organization (PRO) review. That study used volunteer physicians from an institution as gold standard reviewers, however. The article discusses a second experiment employing Utah PRO (UPRO) review physicians as gold standards. Iliad was compared with the Unified Clinical Data Set used by the UPRO and was found to detect otherwise unsuspected diagnostic errors. The confirmation rate of Iliad flags was much higher in the earlier study, however. No agreement was found between institution and UPRO physicians, but there was agreement between a unique physician (who was both an institution and UPRO physician) and each of the two groups. Because Iliad screens for potential diagnostic errors to be confirmed or denied by gold standard physician review, the different types of physicians in the two experiments might have been the cause. 相似文献
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