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31.
Extracellular proteolytic activities were detected in Phytomonas françai culture supernatant. A 67-kDa enzyme was purified by ammonium sulfate precipitation and gel filtration in a HPLC system. This proteinase was optimally active at 28 °C and pH 5.0; and the use of proteolytic inhibitors indicated that it belongs to the metalloproteinase class. This is the first report on the purification of an extracellular metalloproteinase from a Phytomonas species.  相似文献   
32.
Fluorescence in situ hybridization (FISH) is a useful cytogenetic technique for the detection of chromosome aberrations. However, applying this technique routinely on paraffin-embedded tissue is hampered by technical problems. The efficiency of hybridization is influenced by formalin fixation time, and this may vary considerably between specimens. We present a simple method for improving hybridization by microscopically monitoring the time of enzymatic digestion. To establish optimal digestion time, enzymatic digestion was stopped at 3-minute intervals for biopsies and 10-minute intervals for autopsies in 24 paraffin-embedded samples. At every stop, tissue morphology was examined under light microscopy to determine if observed changes could be correlated with subsequent FISH results. The appearance of fernlike formations was found to mark the optimal digestion time that produced the strongest hybridization signals. Using this method of digestion time control, an additional 41 cases were evaluated for FISH with various types of probe. Monitoring under the microscope could be more spaced if the morphology did not change after the first visual control and could be adapted to the type of sample (in general, endoscopic samples, total digestion time of about 10 min; routine biopsies, 15 to 30 min; autopsy samples, 20 to 40 min). In every case, the appearance of the fernlike pattern correlated with proper hybridization signal. Monitoring digestion time for the appearance of fernlike structures is a useful method for improving reproducibility of FISH technique on paraffin-embedded samples. It is particularly useful when dealing with samples under heterogeneous fixation conditions (consultations, autopsies, etc.), because it eliminates the need for repetition.  相似文献   
33.
Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found.  相似文献   
34.
The European Journal of Health Economics - To estimate the prevalence of catastrophic health expenditure due to dental healthcare (CHED) in Spain, quantify its intensity and examine the related...  相似文献   
35.
Thyroidectomy is the most frequent procedure in endocrine surgery. The conventional approach through a collar incision, as described by Kocher in XIXth century, has become the “gold standard”. It is continuously evolving in spite of, many years ago, it showed to be safe and efficient with quality standards difficult to beat.Endoscopic and robotic surgery have developed “new approaches” to thyroid in order to improve the cosmetic results, looking even for invisible scars.We have done a thoughtful review of most of them trying to understand their benefits and drawbacks.Currently none of these “new approaches” have been shown to be better than conventional open thyroidectomy beyond offering a better cosmetic result. Besides, only a small percentage of patients can benefit of them. However, most of these approaches will remain if they treat the diseased thyroid and also improve the quality of life of our patients.  相似文献   
36.
IntroductionRobotic surgery has become a safe and effective approach for the treatment of pulmonary surgical pathology. However, the adoption of new surgical techniques requires the evaluation of the learning curve. The objective of this study is to analyze the learning curve of robotic anatomical lung resections.MethodsRetrospective analysis of all robotic anatomical lung resections performed by the same surgeon between June 2018 and March 2020. The learning curve was evaluated using CUSUM charts to estimate trend changes in surgical time, surgical failure and the occurrence of post-operative cardiorespiratory complications throughout the sequence of cases.ResultsThe study included a total of 73 cases. The median duration of all complications was 120 min (interquartile range: 90-150 min), the prevalence of surgical failure was 23.29%, while 4/73 patients had any postoperative cardiorespiratory complication. Based on the CUSUM analysis, the learning curve was divided into 3 different phases: phase i (from the first to the 14th intervention), phase ii (between the 15th and 30th intervention) and phase iii (from the 31st intervention).ConclusionsThe learning curve for robotic anatomical lung resections can be divided into 3 phases. The technical competence that guarantees satisfactory perioperative outcomes was achived in phase iii from the 31st intervention.  相似文献   
37.
38.
Craniofacial development, one of the most complex sequences of developmental events in embryology, features a uniquely transient, pluripotent stem cell-like population known as the neural crest (NC). Neural crest cells (NCCs) originate from the dorsal aspect of the neural tube and migrate along pre-determined routes into the developing branchial arches and frontonasal plate. The exceptional rates of proliferation and migration of NCCs enable their diverse contribution to a wide variety of craniofacial structures. Subsequent differentiation of these cells gives rise to cartilage, bones, and a number of mesenchymally-derived tissues. Deficiencies in any stage of differentiation can result in facial clefts and abnormalities associated with craniofacial syndromes. A small number of conserved signaling pathways are involved in controlling NC differentiation and craniofacial development. They are used in a reiterated fashion to help define precise temporospatial cell and tissue formation. Although many aspects of their cellular and molecular control have yet to be described, it is clear that together they form intricately integrated signaling networks required for spatial orientation and developmental stability and plasticity, which are hallmarks of craniofacial development. Mutations that affect the functions of these signaling pathways are often directly or indirectly identified in congenital syndromes. Clinical applications of NC-derived mesenchymal stem/progenitor cells, persistent into adulthood, hold great promise for tissue repair and regeneration. Realization of NCC potential for regenerative therapies motivates understanding of the intricacies of cell communication and differentiation that underlie the complexities of NC-derived tissues.  相似文献   
39.
Adipose tissue yields adult adipose stem cells (ASCs) in large quantities via less-invasive methods. These cells are of interest owing to their modulating properties and paracrine activities, which can be harnessed in regenerative medicine. Many studies on the use of rat fat tissue in an autologous animal model have been conducted; however, the different locations to obtain stromal vascular fraction of rat fat depots have not been fully characterized. The purpose of the current study was to identify optimal source of ASC from various locations of rat body. Animal experiments in vitro revealed that fat depots from cervical fat are an optimal ASC source. A high ASC yield facilitates subsequent studies on autologous transplantation in rats. The secondary objective was to compare the efficiency of osteoinductive media composition and evaluate of osteogenic potential of ASCs for seeding on scaffolds for bone repair. Scaffolds were assessed in vitro, using rat adipose stem cells and three-dimensional (3D) scaffolds comprising polycaprolactone (PCL) or polycaprolactone covered with tricalcium phosphate (PCL + 5%TCP). Seeded ASCs adhere to the surface and migrate to the scaffolds. Upon staining and determining alkaline phosphatase levels, PCL + 5%TCP scaffolds performed better than PCL scaffolds. Furthermore, growth factors such as BMP2 and FGF2 significantly increased ASC mineralization and induced osteogenesis (p?<?0.05). Our results may help select and develop pre-clinical animal model for confirming the use of ASC, alone or in association with appropriate biomaterials for bone repair.  相似文献   
40.
BCL-2 protein is a oncoprotein considered to have an important role in the regulation of programmed cell death--apoptosis. The intracellular localization, the relation with other oncoproteins, the antioxidant function and the pathological implications are discussed.  相似文献   
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