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Although existence of ovarian stem cells (OSCs) in mammalian postnatal ovary is still under controversy, however, it has been almost accepted that OSCs are contributing actively to folliculogenesis and neo-oogenesis. Recently, various methods with different efficacies have been employed for OSCs isolation from ovarian tissue, which these methods could be chosen depends on aim of isolation and accessible equipments and materials in lab. Although isolated OSCs from different methods have various traits and characterizations, which might become from their different nature and origin, however these stem cells are promising source for woman infertility treatment or source of energy for women with a history of repeat IVF failure in near future. This review has brought together and summarized currently used protocols for isolation and propagation of OSCs in vitro.  相似文献   
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The advent of microarray tools has generated a massive amount of gene expression data. These data have greatly enhanced our understanding of the biology of breast cancer metastasis and provide a way to improve the prediction of the metastatic potential of breast tumours. Gene-expression profiling has highlighted the molecular heterogeneity of mammary tumours and contributed to the identification of a new molecular classification of breast cancers. In addition, several molecular signatures predicting the likelihood of distant metastases for breast cancer patients have been characterized. Further reports have described gene expression profiles associated with specific metastatic phenotypes, including the organ preference of breast cancer metastasis. Here we review the major studies that had important impacts on the understanding of breast cancer metastasis. We also discuss the future challenges in this research field and the special issues that still need to be examined.  相似文献   
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Metallo-beta-lactamase enzymes (MbetaL) are encoded by transferable genes, which appear to spread rapidly among gram-negative bacteria. The objective of this study was to develop a multiplex real-time PCR assay followed by a melt curve step for rapid detection and identification of genes encoding MbetaL-type enzymes based on the amplicon melting peak. The reference sequences of all genes encoding IMP and VIM types, SPM-1, GIM-1, and SIM-1 were downloaded from GenBank, and primers were designed to obtain amplicons showing different sizes and melting peak temperatures (Tm). The real-time PCR assay was able to detect all MbetaL-harboring clinical isolates, and the Tm-assigned genotypes were 100% coincident with previous sequencing results. This assay could be suitable for identification of MbetaL-producing gram-negative bacteria by molecular diagnostic laboratories.  相似文献   
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The use of sentinel node surgery for esophageal carcinoma is still under investigation. We evaluated the data available in the literature on this topic, and herein present the results in a systematic review format. PUBMED, SCOPUS, the ISI web of knowledge and the information from the annual meetings of the Japan Esophageal Society were searched using the search terms: “(esophagus OR esophageal) AND sentinel”. The outcomes of interest were the detection rate and sensitivity. Overall, 18 studies were included. The pooled detection rate was 89.2 % [82.6–93.5]. Patients with T1 and two tumors had a 17 % higher detection rate compared to those with T3 and four tumors. The pooled sensitivity was 84 % [78–88 %]. The sensitivity was higher for adenocarcinoma compared to squamous cell carcinoma (SCC) (91 vs. 81 %). In the SCC patients, there was a trend toward decreased sensitivity associated with an increasing tumor depth (T1:88 %, T2:76 %, T3:50 %). Our analysis indicated that sentinel node biopsy is useful in adenocarcinoma patients. For SCC patients, including only cN0 patients (preferably T1 and 2) would increase the detection rate and sensitivity. Due to the limited number of high-quality studies, drawing any more definite conclusions is impossible. Large cohort studies with a standardized and consistent design will be needed in the future.  相似文献   
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