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991.
蚤类的种间杂交及其分类学意义 (一)曲棘新蚤×思博新蚤 总被引:3,自引:2,他引:3
作者以曲棘新蚤(NeopsylateraturaRothschild,1913)和思博新蚤(N.siboiYeetYu,1993)为亲本进行了杂交试验。亲本蚤自新疆野外采集,在实验室饲养两代以上纯化后用于杂交试验。两种蚤的饲养器具完全分开,采用平皿湿滤纸法培育蚤的裸蛹,并在蛹期即将雌雄分开,以保证同种蚤亲代两性间无交配。设正交、反交、子代自交和回交四种组合。以能产生F2以上杂种者为杂交可育,否则为杂交不育。以雄性第9腹板后臂鬃的形态、可动突形状及第8腹板后缘鬃序为判定杂交后代归属的形态学特征。杂交结果表明,两亲本蚤杂交可育,产生了F2以上杂种。在正交F1和F2、反交F1以及回交子代中均出现了两亲本蚤形态特征之间的中间型个体,说明两亲本蚤间并不存在生殖隔离,它们实际上是同一个物种。本次试验的结果提示,目前蚤类分类工作中的传统的方法和标准有待通过遗传学试验及现代生物技术方法加以修正和完善。 相似文献
992.
目的:分析肾细胞癌患者接受腹腔镜保留肾单位肾肿瘤切除术治疗对其肾功能及预后的影响。方法:收集2017年1月至2022年3月重庆医科大学附属第一医院泌尿外科接诊的肾细胞癌患者182例作为研究对象,采取随机法将患者进行分组,一组应用腹腔镜根治性肾切除术进行治疗,共91例为对照组,另一组应用腹腔镜保留肾单位肾肿瘤切除术进行治疗,共91例为研究组,对比两组患者术后肾功能及预后效果差异性。结果:研究组患者术后住院时间(P=0.011)优于对照组,对照组患者手术期间出血量(P<0.001)及手术时间(P=0.019)优于研究组,差异均有统计学意义;研究组患者手术后24 h血清肌酐水平(P=0.013)低于对照组,差异有统计学意义;研究组患者术后认知功能(P=0.018)、躯体功能(P=0.021)、社会功能(P=0.025)、情绪功能(P=0.032)及总体生活质量(P=0.033)等各维度评分高于对照组,差异有统计学意义。结论:临床中为肾细胞癌患者提供腹腔镜保留肾单位肾肿瘤切除术进行治疗可以缓解对患者肾功能造成的影响,提升患者手术治疗后的生活质量水平。 相似文献
993.
目的:探讨穿心莲内酯(andrographolide,ANDRO)对叔丁基过氧化氢(tert-butyl hydroperoxide,TBHP)诱导的椎间盘髓核细胞(nucleus pulposus cells,NPC)凋亡的作用及其机制。方法:用TBHP诱导NPC建立细胞模型。将NPC分为5组:对照组、模型组(100μmol/L TBHP)、ANDRO低剂量组(100μmol/L TBHP+9μmol/L ANDRO)、ANDRO中剂量组(100μmol/L TBHP+18μmol/L ANDRO)和ANDRO高剂量组(100μmol/L TBHP+36μmol/L ANDRO)。流式细胞术检测细胞凋亡和活性氧(reactive oxygen species,ROS)水平,ELISA试剂盒检测氧化应激相关指标超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-PX)和过氧化氢酶(catalase,CAT)水平,JC-1探针法检测线粒体膜电位,Western blot检测动力相关蛋白1(dynam... 相似文献
994.
目的 探究急性ST段抬高型心肌梗死(ST-segment elevation myocardial infarction,STEMI)患者新发心房颤动(new-onset atrial fibrillation,NOAF)的风险预测模型构建并验证,以便为尽早发现高风险人群、及时采取干预措施提供依据。方法 选取2017年1月至2021年12月在重庆市第四人民医院心血管内科住院的1 080名STEMI患者,其中院内新发房颤患者作为NOAF组(n=87),从未发生NOAF的STEMI患者中随机抽取一部分作为对照组(n=199),比较2组患者人口学特征及入院时临床资料,利用LASSO回归模型分析STEMI患者发生院内新发心房颤动的风险因素。对纳入的患者按7∶3的比例划分为模型组及验证组,建立个性化的院内NOAF预测模型并进行验证。结果 LASSO回归结果提示,年龄、入院心率、Killip分级≥II级、右房内径、二尖瓣中度以上反流、氨基末端脑钠肽前体(N-terminal pro-B-type natriuretic peptide,NT-proBNP)为STEMI患者发生院内NOAF的重要预测因素(P<0.05)。利用上述6个预测指标构建列线图模型。模型组曲线下面积(area under the curve,AUC)为 0.842(95%CI=0.780~0.905),准确度为0.840(95%CI=0.782~0.888);验证组 AUC 为 0.858(95%CI=0.774~0.943),准确度为0.826(95%CI=0.729~0.899)。同时,校准曲线提示预测模型的校正能力良好。结论 本研究成功构建了STEMI患者院内发生NOAF风险的预测模型,经相关指标证实该预测模型具有较好的预测效率和临床适用性。利用列线图可方便直观地协助临床医护人员筛选高NOAF风险患者,制定针对性的干预措施,为早期防治和改善预后提供依据。 相似文献
995.
目的 探讨肿瘤坏死因子诱导蛋白8样蛋白2(TIPE2)、细胞增殖核抗原Ki67在子宫内膜癌组织中的表达及对患者预后的评估价值。方法 选取2018年1月至2020年1月河北工程大学附属医院妇科收治的子宫内膜癌患者120例作为观察组,另选取同期收治的非子宫内膜癌患者130例作为对照组,所有入组患者均接受手术治疗。回顾性收集患者的临床及病理资料,比较两组患者子宫内膜组织中TIPE2、Ki67的表达水平。同时定期对观察组患者进行随访,分析患者2年生存情况,通过Cox比例风险回归模型分析子宫内膜癌患者预后的影响因素。结果 观察组、对照组子宫内膜组织中TIPE2阳性率分别为28.33%、71.54%。与对照组相比,观察组子宫内膜组织TIPE2阳性率降低(P<0.05);观察组、对照组子宫内膜组织中Ki67阳性率分别为33.33%、5.38%。观察组子宫内膜组织Ki67阳性率高于对照组(P<0.05)。对120例子宫内膜癌患者随访2年,至随访结束,93例患者存活,生存率77.50%。Cox模型分析结果显示,TIPE2阴性(HR=3.736,95%CI=1.016~13.157)为子宫内膜... 相似文献
996.
Economic evaluation of pharmaceuticals: a European perspective 总被引:1,自引:0,他引:1
Drummond M Rutten F Brenna A Pinto CG Horisberger B Jönsson B Le Pen C Rovira J von der Schulenburg MG Sintonen H 《PharmacoEconomics》1993,4(3):173-186
In recent years there has been a large increase in the number of economic evaluations of pharmaceuticals. Many of these studies have been commissioned by individual pharmaceutical companies, in support of new or existing products. In 2 countries, Australia and Canada (in the province of Ontario), draft guidelines issued by the government have outlined the requirements for economic evaluations to be submitted in support of requests for reimbursement (government subsidy) of particular products. One consequence of the guidelines is that they clarify what is required, and in specifying the procedure for submission of dossiers, identify a clear audience for the economic evaluation. In contrast, the situation in Europe is diverse. A wide range of healthcare systems exist, including national health services and more liberal systems, involving a wide range of insurers and providers. European countries also differ widely in their approach to the pricing and reimbursement of pharmaceuticals. Because of this diversity, the nature, conduct and impact of economic evaluation in Europe is not clear. It is therefore difficult for pharmaceutical companies to develop appropriate strategies for economic evaluation and for analysts to decide on appropriate study methodology. This article reviews the nature of any official guidance or requirements for economic evaluation, the potential for use of economic evaluation, the range of studies carried out and the identifiable impacts. There is currently no official guidance in any country, although some countries are considering issuing guidelines. In some countries there is official encouragement to pharmaceutical companies to undertake studies, and where economic data have been presented they have been considered by the relevant committees. The potential uses of economic evaluation vary widely from country to country. These can be classified in terms of a potential role in undertaking national price negotiations, deciding on reimbursement status or copayment level, deciding on inclusion in local formularies or in treatment guidelines, or in improving prescribing decisions. Approximately 80 economic evaluations of pharmaceutical products have been conducted to date in Europe, covering a wide range of clinical areas. There are relatively few examples of identifiable effects of such studies. In part this is because it is often difficult to assess the part played by various items of data. Nevertheless, the overriding conclusion is that economic evaluation of medicines is likely to be more relevant in Europe in the future. The problem for the pharmaceutical industry is in determining when and how. 相似文献
997.
J P Moatti C Le Gales C Julian J L Lanoe S Ayme 《Revue d'épidémiologie et de santé publique》1990,38(4):309-321
The article presents a cost-benefit analysis of amniocentesis for detection of chromosomal anomalies based on data (1985/87) collected in the Marseille area. In this geographic area, it is possible to confront, in an exhaustive manner, pregnant women's access to amniocentesis and incidence of fetal anomalies due to chromosomal aberrations. Results show that prenatal diagnosis is highly cost-beneficial, the average cost of one "avoided" case of Down's syndrome being lower than the lifelong costs of care for such a child. However, the study emphasizes that the cost-benefit ratio is highly sensitive to the implicit value society affects to the loss of "normal" fetuses through spontaneous abortions provoked by amniocentesis and because of terminations of pregnancy following diagnosis of minor fetal anomalies. The study also shows that lowering maternal age limit for access to free-of-charge amniocentesis from the current 38 years of age to 35 would have been cost-beneficial. Such lowering of the maternal age limit is discussed and compared with other indications which might be used for systematic access to amniocentesis. 相似文献
998.
T. Le Penven T. Patrice Mt. Foultier S. Laniepce Y. Lajat F. Maloisel G. Stephan F. Resche 《Lasers in medical science》1990,5(4):387-394
Photodynamic therapy is a new treatment for early carcinomas. Although undergoing phase 1/2 clinical assays, clinical indications for this therapy remain rare mainly because of the approximate dosimetry of HPD uptake by tumour tissues in human beings.In this review we present the potential interest and limits of both direct fluorescence detection or dosimetry of HPD and in vivo measurements of singlet oxygen, produced during photodynamic therapy. Clinical applications of such measurements should represent one of the main conditions for the future development of photodynamic therapy.
Résumé La photochimiothérapie est un nouveau traitement des cancers débutants. Alors que des essais cliniques de phase 1–2 sont entrepris, les indications pour ce type de traitement demeurent rares, principalement du fait d'une dosimétrie approximative de la captation de l'hématoporphyrine dérivée par les tissus cancéreux humains. La fluorescence émise par l'HPD peut Être utilisée in-vivo pour un diagnostique topographique de la répartition de l'HPD, mais aussi le dosage quantitatif des espèces fluorescentes présentes dans le mélange HPD. Le dosage de l'oxygène singulet, généré lors de la réaction photochimique, est nettement plus difficile à réaliser mais a été proposé pour le dosage in-vivo des formes porphyriniques actives présentes dans le milieu. Les applications cliniques de telles mesures représentent une condition essentielle pour le developpement de la photochimiothérapie car à côté des possibilités de diagnotiques offertes par l'analyse de la répartition intratumorale de l'HPD, un dosage précis permettrait d'optimiser le moment du traitement, arbitrairement fixé aujourd'hui à 72 heures.相似文献
999.
A C Begg I Hofland L Moonen H Bartelink S Schraub P Bontemps R Le Fur W Van Den Bogaert R Caspers M Van Glabbeke 《International journal of radiation oncology, biology, physics》1990,19(6):1449-1453
The value of cell kinetic measurements in head and neck tumors in predicting which patients will benefit from accelerated fractionation radiotherapy regimens is being tested in a multicenter European trial (EORTC trial 22851). This paper reports on the first analysis of the correlation of kinetics with outcome in this trial. A proportion of patients in both the accelerated arm (72 Gy in 5 weeks, 1.6Gy per fraction, 45 fractions) and the conventional arm (70-72 Gy in 7-8 weeks, 1.8-2.0 Gy per fraction, 35-40 fractions) were given an i.v. injection of 100 mg/m2 IUdR (iododeoxyuridine) before treatment, and a tumor biopsy was taken several hours later. The potential doubling time of the tumor (Tpot) was obtained from a flow cytometric analysis of tumor cell nuclei using an anti-IUdR antibody. From a total of 260 patients entered in the trial, 53 have undergone kinetic analysis. Adequate IUdR labeling was seen in 47 patients (88.7%), from which the mean value for Tpot was found to be 4.5 +/- 2.5 days (+/- S.D.). Of the IUdR labeled patients, 30 have now been followed up for at least 1 year, 17 with conventional and 13 with accelerated radiotherapy. These patients were split into those with fast and those with slowly growing tumors, the dividing line being the median Tpot value of 4.6 days. After conventional 7-week radiotherapy, 2 of 6 patients with "fast" growing tumors obtained local control compared with 8 of 11 with "slow" growing tumors. A small difference in local control was seen been fast and slow tumors in the accelerated arm (5/9 vs. 3/4). These preliminary data support the hypothesis that patients with fast growing tumors do poorly with conventional radiotherapy and that pretreatment kinetic measurements can select patients at risk. The predictive power of the method must await the final analysis of trial results. 相似文献
1000.
低血流心肌缺血诱导GLUT4基因表达 总被引:1,自引:0,他引:1
目的:探讨低血流心肌缺血促进葡萄糖摄取增加的机制。方法:采用Northrn印迹法观察缺血心肌葡萄转运子4(GLUT4)mRNA的表达,并利用蛋白质印迹法分析心肌GLUT4多肽的表达,结果:局部心肌低血流缺血后,心肌GLUT4mRNA和GLUT4多肽表达明显增加;同时伴随缺血心肌葡萄糖摄取明显增多。结论:心肌缺血能刺激GLUT4 mRNA和GLUT4多肽表达,使GLUT4数增加,进而促进心肌葡萄糖摄取增多,使缺血心肌能量需求得以平衡,有助于缺血心肌功能的恢复,提示低血流缺 刺激心肌GLUT4表达是一个重要的代偿性保护机制。 相似文献