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Ovarian stimulation for assisted reproductive technology (ART) overcomes the physiologic process to develop a single dominant follicle. However, following stimulation, egg recovery rates are not 100%. The objective of this study is to determine if the follicular fluid hormonal environment is associated with oocyte recovery.  相似文献   
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Zofenopril is a pro-drug designed to undergo metabolic hydrolysis yielding the active free sulfhydryl compound zofenoprilat, which is an angiotensin converting enzyme (ACE) inhibitor, endowed also with a marked cardioprotective activity. A simple, highly sensitive specific LC–MS–MS method was developed for the determination of zofenopril and zofenoprilat in human plasma. In order to prevent oxidative degradation of zofenoprilat and its internal standard, their free sulfhydryl groups were protected by treatment with N-ethylmaleimide (NEM), which produced the succinimide derivatives. The compounds and their corresponding fluorine derivatives, used as internal standards, were extracted from plasma with toluene. The reconstituted dried extracts were chromatographed and then monitored by a triple-stage-quadrupole instrument operating in the negative ion spray ionization mode. The method was validated over the concentration range of 1–300 ng/ml for zofenopril and 2–600 ng/ml for zofenoprilat. Inter- and intra-assay precision and accuracy of both zofenopril and zofenoprilat were better than 10%. The limit of quantitation was 1 ng/ml with zofenopril and 2 ng/ml with zofenoprilat. Extraction recovery proved to be on average 84.8% with zofenopril and 70.1% with zofenoprilat. Similar recoveries were shown by the above two internal standards. The method was applied to measure plasma concentrations of zofenopril and zofenoprilat in 18 healthy volunteers treated orally with zofenopril calcium salt at the dose of 60 mg.  相似文献   
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The purposes of this article are to quantify the relationship between epiphytic lichen distribution and macroclimatic variables in the study area and to provide a case study for evaluating the predictive role of epiphytic lichens as bioclimatic indicators. The study was carried out in the Liguria region (NW-Italy), a small (5432 km2) borderline area, where phytoclimatic features range from the dry Mediterranean to the Alpine in a few kilometers. Epiphytic lichen diversity was sampled using a standardized protocol [Asta et al (2002) In: Nimis et al (eds) Monitoring with lichens: monitoring lichens. Kluwer, Dordrecht]. Abundance of the species in the sampling sites was related to macroclimatic parameters (yearly average temperature and rainfall) and non-parametric multivariate models were calculated to find significative relationships among predictive and response variables. A total of 59 species showed highly significant relation with macroclimatic parameters. Four groups were selected, by means of a cluster analysis, related to four climatic niches (warm-humid, cold-humid, mesothermic-humid, warm-dry). Distributional pattern of the groups in the survey area showed a good correspondence with the bioclimatic units of Liguria region described by Nimis [(2003) Checklist of the Lichens of Italy 3.0. University of Trieste, Dept of Biology. http://www.dbiodbs.univ.trieste.it. Cited 1 Jun 2006]. A significant subset of epiphytic lichen species in the study area have been proved to be efficient bioclimatic indicator and it is supposed to give good results to monitor climatic changes, in a long-term perspective.  相似文献   
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Increasing knowledge on the cell cycle deregulations in cancers has promoted the introduction of phytochemicals, which can either modulate signaling pathways leading to cell cycle regulation or directly alter cell cycle regulatory molecules, in cancer therapy. Most human malignancies are driven by chromosomal translocations or other genetic alterations that directly affect the function of critical cell cycle proteins such as cyclins as well as tumor suppressors, e.g., p53. In this respect, cell cycle regulation and its modulation by curcumin are gaining widespread attention in recent years. Extensive research has addressed the chemotherapeutic potential of curcumin (diferuloylmethane), a relatively non-toxic plant derived polyphenol. The mechanisms implicated are diverse and appear to involve a combination of cell signaling pathways at multiple levels. In the present review we discuss how alterations in the cell cycle control contribute to the malignant transformation and provide an overview of how curcumin targets cell cycle regulatory molecules to assert anti-proliferative and/or apoptotic effects in cancer cells. The purpose of the current article is to present an appraisal of the current level of knowledge regarding the potential of curcumin as an agent for the chemoprevention of cancer via an understanding of its mechanism of action at the level of cell cycle regulation. Taken together, this review seeks to summarize the unique properties of curcumin that may be exploited for successful clinical cancer prevention.  相似文献   
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Current analysis of circulating tumor cells (CTCs) is hindered by sub-optimal sensitivity and specificity of devices or assays as well as lack of capability of characterization of CTCs with clinical biomarkers. Here, we validate a novel technology to enrich and characterize CTCs from blood samples of patients with metastatic breast, prostate and colorectal cancers using a microfluidic chip which is processed by using an automated staining and scanning system from sample preparation to image processing. The Celsee system allowed for the detection of CTCs with apparent high sensitivity and specificity (94% sensitivity and 100% specificity). Moreover, the system facilitated rapid capture of CTCs from blood samples and also allowed for downstream characterization of the captured cells by immunohistochemistry, DNA and mRNA fluorescence in-situ hybridization (FISH). In a subset of patients with prostate cancer we compared the technology with a FDA-approved CTC device, CellSearch and found a higher degree of sensitivity with the Celsee instrument. In conclusion, the integrated Celsee system represents a promising CTC technology for enumeration and molecular characterization.  相似文献   
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BackgroundFibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks.MethodsA comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors.ResultsA total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a significant advantage to fibrin sealant use. Two small case series studies evaluated the effect of fibrin sealants in persistent cerebrospinal fluid leak treatment, but did not establish firm efficacy conclusions. Specific adverse reports where fibrin sealants were used for dura sealing were limited, with only 8 cases reported in neurosurgical procedures since 1987 and most reporting only a speculative relationship/association with fibrin sealant exposure.ConclusionsA major finding of this systematic literature review is that there is a paucity of randomized studies that have evaluated the effectiveness and safety of fibrin sealants in providing intraoperative watertight dura closure and post-operative cerebrospinal fluid leakage. Among the limited studies available, evidence from a single randomized, controlled trial indicates that fibrin sealants provide a higher rate of intraoperative watertight closure of the dura suture line than control, albeit with a higher rate of postoperative cerebrospinal fluid leakage. Evidence from non-randomized, controlled trials suggests that fibrin sealants may be effective in preventing cerebrospinal fluid leaks with an acceptable safety profile. There is a substantial need for randomized, controlled clinical trials or well-designed prospective observational trials where the conduct of a randomized trial is not feasible to fully assess the impact of fibrin sealant utilization on the rates of intraoperative dura closure, postoperative cerebrospinal leakage, and safety.  相似文献   
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The aim of this study was to identify plant species among the diverse flora of the caatinga ecosystem that are used therapeutically. Research was undertaken in the municipalities of Piranhas and Delmiro Gouveia, in the Xingó region (state of Alagoas, NE Brazil). In order to identify the medicinal plants used in this region, semi-structured questionnaires were applied. The species cited were collected and sent to the Xingó Herbarium for taxonomic analysis. The relative importance (RI) of each species cited was calculated to verify their cultural importance. The therapeutic indications attributed to the species were classified under 16 body systems. A total of 187 medicinal species were cited, from 64 families and 128 genera. The main indications for medicinal plant use were against common colds, bronchitis, cardiovascular problems, kidney problems, inflammations in general, and as tranquilizers. Approximately 16% (30 plant species) were versatile in relation to their use, with an Relative Importance value over 1, having been indicated for up to nine body systems. The body systems that stood out the most were: the respiratory system, the gastrointestinal system, and infectious diseases. Most cited plant parts used for medicinal purposes were flowers, leaves, and inner stem bark.  相似文献   
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