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Reptile development is an intriguing research target for understating the unique morphogenesis of reptiles as well as the evolution of vertebrates. However, there are numerous difficulties associated with studying development in reptiles. The number of available reptile eggs is usually quite limited. In addition, the reptile embryo is tightly adhered to the eggshell, making it a challenge to isolate reptile embryos intact. Furthermore, there have been few reports describing efficient procedures for isolating intact embryos especially prior to pharyngula stage. Thus, the aim of this review is to present efficient procedures for obtaining early‐stage reptilian embryos intact. We first describe the method for isolating early‐stage embryos of the Japanese striped snake. This is the first detailed method for obtaining embryos prior to oviposition in oviparous snake species. Second, we describe an efficient strategy for isolating early‐stage embryos of the soft‐shelled turtle.  相似文献   
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The goal of this study was to investigate microRNAs (miRs) expression at different stages of nasopharyngeal carcinoma (NPC). MiR expression profiling at various stages of NPC was performed by miR array and further verified using quantitative real‐time RT‐PCR. Pathway enrichment analysis was carried out to identify the functional pathways regulated by the miRs. The expression of a selected group of identified miRs was verified in stage I NPC by in situ hybridization (ISH). A total of 449 miRs were identified with significantly different expressions between NPC tissues and normal pharyngeal tissues. Eighty‐four miRs were dysregulated only in stage I NPC, among which 45 miRs were up‐regulated and the other 39 were down‐regulated. Pathway enrichment assay revleaed that three significantly down‐regulated and three significantly up‐regulated miRs involved in 12 pathways associating with tumour formation and progression. Quantitative RT‐PCR confirmed the miR array result. In addition, the low expression levels of hsa‐miR‐4324, hsa‐miR‐203a and hsa‐miR‐199b‐5p were further validated in stage I NPC by ISH. This present study identifed the miR signature in stage I NPC, providing the basis for early detection and treatment of NPC.  相似文献   
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Introduction: Esophageal cancer (EC) is one of the most common causes of cancer-related death worldwide. Identifying suitable biomarkers for early diagnosis as well as predicting lymph node metastasis, prognosis and the therapeutic response of EC is essential for the effective and efficient management for EC. There is an urgent need to develop effective, novel approaches for patients who do not respond to conventional treatment.

Areas covered: EC is characterized by the presence of two main histological types such as squamous cell carcinoma and adenocarcinoma, which differ in their response to treatments and prognosis. Thus, this review describes the latest research into biomarkers and novel treatment targets generated by cancer proteomics for the two main histological types. Finally, the main difficulties facing the translation of biomarkers and novel treatment targets into the clinical settings are discussed.

Expert commentary: EC proteomics have provided useful results and, after their validation, novel clinical tools should be developed to improve the clinical outcomes for EC patients.  相似文献   

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BackgroundCurrent concepts in conservative dentistry advocate minimally invasive dentistry and pulp vitality preservation. Moreover, complete removal of carious dentin in deep carious lesions often leads to pulp exposure and root canal treatment, despite the absence of irreversible pulp inflammation. For years, partial caries removal has been performed on primary teeth, but little evidence supports its effectiveness for permanent teeth. Furthermore, the recent development of new antibacterial adhesive systems could be interesting in the treatment of such lesions. The objectives of this study are to compare the effectiveness of partial versus complete carious dentin removal in deep lesions (primary objective) and the use of an antibacterial versus a traditional two-step self-etch adhesive system (main secondary objective).Methods/DesignThe DEep CAries Treatment (DECAT) study protocol is a multicenter, randomized, controlled superiority trial comparing partial versus complete caries removal followed by adhesive restoration. The minimum sample size required is 464 patients. Two successive randomizations will be performed (allocation ratio 1:1): the first for the type of excavation (partial versus complete) and the second (if no root canal treatment is required) for the type of adhesive (antibacterial versus traditional). For the two objectives, the outcome is the success of the treatment after 1 year, measured according to a composite outcome of five FDI criteria: material fracture and retention, marginal adaptation, radiographic examination (including apical pathologies), postoperative sensitivity and tooth vitality, and carious lesion recurrence.DiscussionThe study will investigate the interest of a conservative approach for the management of deep carious lesions in terms of dentin excavation and bioactive adhesive systems. The results may help practitioners achieve the most efficient restorative procedure to maintain pulp vitality and increase the restoration longevity.

Trial registration

ClinicalTrials.gov Identifier NCT02286388. Registered in November 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1484-0) contains supplementary material, which is available to authorized users.  相似文献   
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Epidemiological evidence demonstrates that cannabis use is associated with an increased risk of psychotic outcomes, and confirms a dose‐response relationship between the level of use and the risk of later psychosis. High‐potency cannabis and synthetic cannabinoids carry the greatest risk. Experimental administration of tetrahydrocannabinol, the active ingredient of cannabis, induces transient psychosis in normal subjects, but this effect can be ameliorated by co‐administration of cannabidiol. This latter is a constituent of traditional hashish, but is largely absent from modern high‐potency forms of cannabis. Argument continues over the extent to which genetic predisposition is correlated to, or interacts with, cannabis use, and what proportion of psychosis could be prevented by minimizing heavy use. As yet, there is not convincing evidence that cannabis use increases risk of other psychiatric disorders, but there are no such doubts concerning its detrimental effect on cognitive function. All of the negative aspects are magnified if use starts in early adolescence. Irrespective of whether use of cannabis is decriminalized or legalized, the evidence that it is a component cause of psychosis is now sufficient for public health messages outlining the risk, especially of regular use of high‐potency cannabis and synthetic cannabinoids.  相似文献   
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Personalized medicine is rapidly becoming a reality in today's physical medicine. However, as yet this is largely an aspirational goal in psychiatry, despite significant advances in our understanding of the biochemical, genetic and neurobiological processes underlying major mental disorders. Preventive medicine relies on the availability of predictive tools; in psychiatry we still largely lack these. Furthermore, our current diagnostic systems, with their focus on well‐established, largely chronic illness, do not support a pre‐emptive, let alone a preventive, approach, since it is during the early stages of a disorder that interventions have the potential to offer the greatest benefit. Here, we present a clinical staging model for severe mental disorders and discuss examples of biological markers that have already undergone some systematic evaluation and that could be integrated into such a framework. The advantage of this model is that it explicitly considers the evolution of psychopathology during the development of a mental illness and emphasizes that progression of illness is by no means inevitable, but can be altered by providing appropriate interventions that target individual modifiable risk and protective factors. The specific goals of therapeutic intervention are therefore broadened to include the prevention of illness onset or progression, and to minimize the risk of harm associated with more complex treatment regimens. The staging model also facilitates the integration of new data on the biological, social and environmental factors that influence mental illness into our clinical and diagnostic infrastructure, which will provide a major step forward in the development of a truly pre‐emptive psychiatry.  相似文献   
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