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排序方式: 共有316条查询结果,搜索用时 15 毫秒
1.
The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions.  相似文献   
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Altered adhesion plaques have been observed in transformed cell lines and are associated with enhanced metastatic potential. The prototypical adhesion plaque is formed by 51 fibronectin receptors (FnRs) interacting with the cellular actin network. We have found differences in the actin networks of noninvasive (FTC-133) and invasive (FTC-236, FTC-238) clones of a human follicular thyroid cancer cell line. Furthermore, thyroid-stimulating hormone (TSH) induces stress fibers in FTC-133. In order to investigate differences in adhesion plaques, expression of fibronectin (FN) and its receptor by these cells was analyzed. For these studies FTC-133, FTC-236, and FTC-238 were cultured in serum-depleted DME-H21 medium for 24 hours before the addition of TSH 30 mU/ml. No quantitative differences were noted in FN expression on Western blot in either the conditioned medium or cellular extracts. Western blots and immunohistochemical studies indicated that TSH induced secretion of FN only in FTC-133. Flow cytometry with an 5 antibody demonstrated a 52% and 45% reduction (p<0.01) in expression of FnR by FTC-236 and FTC-238, respectively, compared to FTC-133; this finding was supported by immunohistochemistry results. TSH treatment did not alter FnR expression. From these studies, we conclude that invasive clones of FTC decrease their expression of FnRs without changing their expression of FN. Furthermore, TSH treatment may promote FN secretion by FTC-133, although it does not seem to affect FnR or absolute FN expression. The diminished expression of FnR adhesion plaques may enhance metastatic potential in some follicular thyroid cancers.
Resumen Se han observado placas adhesivas alteradas en líneas celulares transformadas en asociación con un potencial metastásico incrementado. La prototípica placa adhesiva se forma por la interacción de receptores 5-1 con la trama celular de actina. Hemos encontrado diferencias en las tramas de actina en clones no invasivos (FTC-133) e invasivos (FTC-236, FTC-238) de una línea celular de cáncer folicular de tiroides.Además, la TSH induce líneas de estrés en FTC-133. Con el objeto de investigar las diferencias en las placas adhesivas, se hizo el análisis de la expresión de fibronectina (FN) y sus receptores en tales células.Para estos estudios se hizo el cultivo de FTC-133, FTC-236 y FTC-238, en sueros depletados de DME-H21 por 24 horas anteriores a la adición de 30 mU/ml TSH por 24 horas. No se observaron diferencias cuantitativas en la expresion de FN o en el Western blot ni en los medios condicionados ni en los extractos celulares. Los Western blots y los estudios inmunohistoquímicos indicaron que la TSH induce la secreción de FN sólo en FTC-133. La citometría de flujo con un anticuerpo 5 demostró una reducción de 52% y 45% (p<0.01) en la expresión de FnR por FTC-236 y FT-238, respectivamente, en comparación con FTC-133; este hallazgo fue verificado por inmuno-histoquímica. El tratamiento con TSH no alteró la expresón FnR. Con base en estos estudios, es nuestra conclusión que los clones invasivos de FTC disminuyen la expresión de FnR sin cambiar su expresión de FN. Además, el tratamiento con TSH puede promover la secreciòn de FN por FTC-133, aunque no parece afectar la expresión de FnR o la expresión absoluta de FN. Esta expresión disminuída de las placas adhesivas FnR puede incrementar el potencial metastásico en algunos cánceres foliculares de tiroides.

Résumé On a observé des altérations des plaques d'adhésion dans certaines lignées cellulaires transformées, et celles-ci semblent être associées à un potentiel métastatique augmenté. La plaque d'adhésion prototypique est formée par des récepteurs 51 de fibronectine (FnR) qui agissent sur le réseau cellulaire d'actine. Nous avons trouvé une différence entre les réseaux d'actine des clones noninvasifs (FTC-133) et invasifs (FTC-236, FTC-238) des lignées cellulaires dans le cancer folliculaire de la thyroïde chez l'homme. La TSH induit des fibres de stress dans le FTC-133. Afin d'évaluer les différences dans les plaques d'adhésion, l'expression de la fibronectine (FN) et de son récepteur ont été analysées. Pour ces études, les clones FTC-133, FTC-236 et FTC-238 ont été mis en culture dans le milieu DME-H21 dépourvu en sérum pendant 24 heures avant l'addition de 30 mU/ml de TSH/24 heures. II n'y avait aucune différence quantitative dans l'expression FN sur Western blot que ce soit sur le milieu ainsi conditionné ou sur les extraits cellulaires. Les Western blots et les études immunohistochimiques ont indiqué que la TSH n'induisait la sécrétion de FN que dans la lignée FTC-133. La cytométrie de flux avec l'anticorps 5 a démontré une réduction respectivement de 52% et de 45% (p<0.01) dans l'expression de FnR par les clones FTC-236 et FTC-238, comparé au FTC-133. Cette donnée a été confirmée par l'immunohistochimie. A partir de ces études, nous concluons que les clones d'invasion de FTC diminuent leur expression en FnR sans changer leur expression de FN. De plus, un traitement par la TSH peut induire la sécrétion de FN par le clone FTC-133 alors qu'il ne semble pas influencer le FnR ou l'expression FN. L'expression diminuée des plaques d'adhésion FnR semble potentialiser les métastases dans certains cancers de la thyroïde.
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3.
Non-medical approaches including cognitive behavioral therapy (CBT) have been proposed for the management of tocophobia. A new method of performing CBT is through internet. The aim of this systematic review and meta-analysis was to evaluate the effect of internet-based and traditional CBT on tocophobia. A literature search was conducted on qualitative and quantitative articles from 2000 to 2019 in Pubmed, Scopus, Web of Science and Cochrane databases using search terms referring to tocophobia and CBT. Identified articles were screened in two steps; 1) title and abstract and 2) full text screening. The quality of the quantitative and qualitative studies was assessed using the quality criteria proposed by the Cochrane Collaboration and Jonna Briggs Institute (JBI) checklist respectively. Out of the 382 relevant studies, 9 studies were eligible for the review. A high level of heterogeneity was observed in the studies (I2 = 94%, P < 0.001). The meta-analysis showed that both internet-based, and traditional CBT were effective in reducing tocophobia. CBT was more effective in interventions in the Middle Eastern compared to European countries. More than five CBT sessions could significantly reduce tocophobia. Healthcare providers and midwives should have basic knowledge on physiological interventions to reduce tocophobia.  相似文献   
4.
Deep eutectic solvents (DESs) were used as environmentally benign and straightforward replacements for the harmful organic solvents and transition metal-based catalysts in various organic syntheses. Here, we report a DES as a mild, biocompatible, and environmentally friendly dual solvent/catalyst for the one-pot construction of 2-amino-5-alkylidenethiazol-4-ones throw one-pot reaction of carbonyl compounds, nitrogen compounds, and rhodanine up to quantitative yields within a latent period of times. This green procedure has a more diverse and broader scope regarding starting materials and exhibits excellent conversion and high selectivity. In particular, DES displays better durability and reusability in the multicomponent reactions than traditional catalysts and solvents without distinct deterioration in catalytic activity.  相似文献   
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Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.

Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production.  相似文献   
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Cyclophosphamide is an antineoplastic medicine that causes disorder in functions of the body systems. Thus, the purpose of this study is to investigate the effect of hydroalcoholic extract of saffron on improving the complications of cyclophosphamide on sex hormones. Fifty-six adult female Wistar rats were randomly divided into seven groups; control, sham (received distilled water, solvent extract, and drug), experimental groups 1, 2, and 3 (received cyclophosphamide (5 mg/kg/bw) + hydroalcoholic extract of saffron (2, 1, and 0.5 g/kg/bw), experimental group 4 (saffron 2 g/kg/bw), and experimental group 5 (cyclophosphamide 5 mg/kg/bw). Cyclophosphamide was given intraperitoneally, and extract by gavage was prescribed for 21 days. At the end of the experiment, after blood and preparation of serum, ELISA method was used for measuring the estrogen, progesterone, FSH, and LH hormones. Data and LSD test were analyzed with SPSS software (version 18). Results show that the concurrent use of low-dose cyclophosphamide and saffron extract can reduce toxic effect of cyclophosphamide on pituitary-gonadal axis and cause estrogen to be produced.  相似文献   
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