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排序方式: 共有224条查询结果,搜索用时 31 毫秒
31.
目的:探讨红细胞分布宽度血小板比率(RDW)和中性粒细胞淋巴细胞比率(NLR)预测急诊经皮冠状动脉介入(PCI)术后冠脉无复流的应用价值。方法:选取2016年1月~2016年12月于我院行急诊PCI手术治疗的患者66例为研究对象,检测其治疗前的RDW和NLR,统计其急诊PCI术后冠脉无复流现象的发生情况,比较冠脉无复流和正常血流患者的RDW和NLR,分析患者RDW和NLR与其冠脉无复流的关系及其对冠脉无复流的预测价值。结果:66例患者急诊PCI术后冠脉无复流发生率为30.30%(20/66)。与正常血流患者比较,冠脉无复流患者RDW和NLR均升高(P0.05)。Spearman相关分析结果显示患者RDW和NLR与其冠脉无复流均呈正相关(r=0.826,0.878,P0.05)。进一步ROC曲线分析结果显示急诊PCI术前RDW和NLR联合预测其术后冠脉无复流的的ROC曲线下面积高于二者单独预测。结论:急诊PCI患者RDW和NLR与其术后冠脉无复流密切相关且两者联合预测患者术后冠脉无复流的价值良好,可能作为急诊PCI术后冠脉无复流评估的参考指标。  相似文献   
32.
PURPOSE: The monocyte-to-lymphocyte ratio (MLR) has been shown to be associated with the prognosis of various solid tumors. This study sought to evaluate the important value of the MLR in ovarian cancer patients. METHODS: A total of 133 ovarian cancer patients and 43 normal controls were retrospectively reviewed. The patients'' demographics were analyzed along with clinical and pathologic data. The counts of peripheral neutrophils, lymphocytes, monocytes, and platelets were collected and used to calculate the MLR, neutrophil-to-lymphocyte ratio (NLR). and platelet-to-lymphocyte ratio (PLR). The optimal cutoff value of the MLR was determined by using receiver operating characteristic curve analysis. We compared the MLR, NLR, and PLR between ovarian cancer and normal control patients and among patients with different stages and different grades, as well as between patients with lymph node metastasis and non–lymph node metastasis. We then investigated the value of the MLR in predicting the stage, grade, and lymph node positivity by using logistic regression. The impact of the MLR on overall survival (OS) was calculated by Kaplan-Meier method and compared by log-rank test. RESULTS: Statistically significant differences in the MLR were observed between ovarian cancer patients and normal controls. However, no difference was found for the NLR and PLR. Highly significant differences in the MLR were found among patients with different stages (stage I-II and stage III-IV), grades (G1 and >G1), and lymph node metastasis status. The MLR was a significant and independent risk factor for lymph node metastasis, as determined by logistic regression. The optimal cutoff value of the MLR was 0.23. We also classified the data according to tumor markers (CA125, CA199, HE4, AFP, and CEA) and conventional coagulation parameters (International Normalized Ratio [INR] and fibrinogen). Highly significant differences in CA125, CA199, HE4, INR, fibrinogen levels, and lactate dehydrogenase were found between the low-MLR group (MLR ≤ 0.23) and the high-MLR group (MLR > 0.23). Correspondingly, dramatic differences were observed between the two groups in OS. CONCLUSION: Our results show that the peripheral blood MLR before surgery could be a significant predictor of advanced stages, advanced pathologic grades, and positive lymphatic metastasis in ovarian cancer patients.  相似文献   
33.
Dysregulation of microRNAs (miRNAs) is actively involved in the pathogenesis and tumorigenicity of hepatocellular carcinoma (HCC). miR-489 was found to play either oncogenic or tumor suppressive roles in human cancers. Recent study reported that the levels of miR-489 in late recurrent HCC patients were evidently higher than that in early recurrent cases, suggesting that miR-489 may function as a tumor suppressive miRNA in HCC. Yet, the clinical value and biological function of miR-489 remain rarely known in HCC. Here, we presented that miR-489 level in HCC tissues was notably reduced compared to matched non-cancerous specimens. Its decreased level was evidently correlated with adverse clinical parameters and poor prognosis of HCC patients. Accordingly, the levels of miR-489 were obviously down-regulated in HCC cells. Ectopic expression of miR-489 in HCCLM3 and MHCC97H cells prominently inhibits the migration and invasion of tumor cells and reduced lung metastases in vivo, while miR-489 knockdown increased these behaviors of HepG2 and MHCC97L cells. Mechanically, miR-489 negatively regulated matrix metalloproteinase-7 (MMP7) abundance in HCC cells. Herein, MMP7 was found to be a downstream molecule of miR-489 in HCC. An inversely correlation between miR-489 and MMP7 was confirmed in HCC specimens. MMP7 knockdown prohibited cell migration and invasion while MMP7 overexpression showed opposite effects on HCC cells. Furthermore, restoration of MMP7 expression could abrogate the anti-metastatic effects of miR-489 on HCCLM3 cells with enhanced cell migration and invasion. Altogether, miR-489 potentially acts as a prognostic predictor and a drug-target for HCC patients.  相似文献   
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35.
瘦寄蝇属Leptothelaira Mesnil et Shima隶于长足寄蝇亚科Dexinae瘦寄蝇族Leptothelairini;其体细长,后足基节上部具1宽而闭合的骨化桥,翅R4 5脉基部背面具1根小鬃;已知分布于俄罗斯远东南部、日本、越南、尼泊尔和我国台湾.本文记述了采自我国广西龙胜华坪的瘦寄蝇属1新纪录种:东方瘦寄蝇L.orientalis Mesnil et Shima,1979和产自陕西太白山和山西沁源与方山的1新种:长茎瘦寄蝇L.longipennis sp.nov,新种与分布东洋区的南方瘦寄蝇L.meridionalis Mesnil et Shima近似,但单眼鬃弱于内顶鬃,腹部第4背板后1/4~1/5和第5背板完全黑,第5腹板基部圆,中央裂深且基部宽,侧尾叶端部较窄而尖等.新种模式标本保存在沈阳师范大学昆虫研究所.  相似文献   
36.
Plastidial degradation of transitory starch yields mainly maltose and glucose. Following the export into the cytosol, maltose acts as donor for a glucosyl transfer to cytosolic heteroglycans as mediated by a cytosolic transglucosidase (DPE2; EC 2.4.1.25) and the second glucosyl residue is liberated as glucose. The cytosolic phosphorylase (Pho2/PHS2; EC 2.4.1.1) also interacts with heteroglycans using the same intramolecular sites as DPE2. Thus, the two glucosyl transferases interconnect the cytosolic pools of glucose and glucose 1-phosphate. Due to the complex monosaccharide pattern, other heteroglycan-interacting proteins (HIPs) are expected to exist.Identification of those proteins was approached by using two types of affinity chromatography. Heteroglycans from leaves of Arabidopsis thaliana (Col-0) covalently bound to Sepharose served as ligands that were reacted with a complex mixture of buffer-soluble proteins from Arabidopsis leaves. Binding proteins were eluted by sodium chloride. For identification, SDS-PAGE, tryptic digestion and MALDI-TOF analyses were applied. A strongly interacting polypeptide (approximately 40 kDa; designated as HIP1.3) was observed as product of locus At1g09340. Arabidopsis mutants deficient in HIP1.3 were reduced in growth and contained heteroglycans displaying an altered monosaccharide pattern. Wild type plants express HIP1.3 most strongly in leaves. As revealed by immuno fluorescence, HIP1.3 is located in the cytosol of mesophyll cells but mostly associated with the cytosolic surface of the chloroplast envelope membranes. In an HIP1.3-deficient mutant the immunosignal was undetectable. Metabolic profiles from leaves of this mutant and wild type plants as well were determined by GC-MS. As compared to the wild type control, more than ten metabolites, such as ascorbic acid, fructose, fructose bisphosphate, glucose, glycine, were elevated in darkness but decreased in the light. Although the biochemical function of HIP1.3 has not yet been elucidated, it is likely to possess an important function in the central carbon metabolism of higher plants.  相似文献   
37.
探索空间环境对农作物生长的影响是充分发掘和利用航天育种技术优势的重要前提和基础。利用神舟十号飞船搭载小麦主推品种济麦22,对幼苗的生长势、苗高、鲜重和根长等主要指标进行对比分析,利用植物特异的叶绿素荧光技术研究上述指标变化的生理原因,并检测遗传物质的表观修饰状态。结果表明,飞船搭载小麦种子萌发的幼苗与地面对照相比鲜重降低,根长变短,根系数变少。叶绿素荧光参数测定发现,经过空间搭载的种子产生幼苗各种生长指标的差异是空间环境对植物产生的生理胁迫原因所致。经过空间飞行的种子萌发产生的幼苗,其基因组的甲基化修饰程度与对照相比发生了明显改变。  相似文献   
38.
For the first time a finger print analysis via high-performance thin layer chromatography (HPTLC) of Boswellia Sp. Burseraceae was accomplished. A preliminary investigation of the Boswellia Sp. Burseraceae displayed the presence of chemical constituents that could be involved in the production of innovative pharmaceuticals for an array of antiviral, anticancer, and antibacterial uses. Moreover, the finger print analysis would deem useful for establishing HPTLC standardization for natural and herbal photochemical constituents.  相似文献   
39.
Abstract: It is common practice in microdialysis studies for probes to be “calibrated” in artificial CSF and in vitro recoveries determined for all substances to be measured in vivo. Dialysate concentrations of such substances are then “corrected” for in vitro recoveries to provide “estimates” of extracellular concentrations. At least for dopamine, in vitro and in vivo recoveries are significantly different and, therefore, an estimate of extracellular dopamine based on correction for in vitro recovery is likely to be erroneous. Generally, however, the relative relationships of such estimates among animals are of interest rather than the “true” extracellular values. Such relationships would be valid to the extent that estimated values are correlated with or predictive of true values. Using the “no net flux” procedure, the present study sought to determine, for both dopamine and its metabolite 3,4-dihydroxy-phenylacetic acid (DOPAC), whether in vitro and in vivo recoveries would correlate with each other as well as whether respective estimated and true (no net flux) values of these substances would correlate with each other. Probes (3 mm; BAS/CMed MF-5393), previously calibrated, were lowered into both the nucleus accumbens and striatum of freely moving rats the day before sample collection was begun. In vitro and in vivo recoveries were not significantly correlated (r= 0.1–0.3), for either dopamine or DOPAC. For both dopamine and DOPAC, however, there were significant correlations (r= 0.7–0.8) between estimated and true values. Surprisingly, when using these commercial probes, absolute dialysate levels for both substances were even better correlated (r = 0.9–0.95) with true values. This suggests that, with these probes, a direct comparison of dialysate concentrations can be used to determine relative changes in basal extracellular levels of dopamine and DOPAC when it is not practical to do no net flux studies (e.g., because of the time required to characterize a drug effect). The use of in vitro calibrations adjusts the values closer to the true values but also adds noise to each value and therefore should be avoided.  相似文献   
40.
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