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In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
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An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device.  相似文献   
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In the present study, we aimed to observe the effects of ethanol extract of Oxalis corniculata L. on bleeding time (BT) and coagulation time (CT) and determine its acute toxicity in mice. Firstly, the ethanol extract of O. corniculata was administered to 40 mice, which were randomly divided into the normal control group, Yunnan Baiyao control group, low-dose group, and high-dose group. The low-dose (0.6 g/kg) and high-dose (1.2 g/kg) groups received ethanol extract of O. corniculata by gavage, and the BT and CT of the mice were measured by the slide method and tail clipping method, respectively. Secondly, the median lethal dose method was used with 50 mice to observe the physiological state, poisoning reaction, and death of the mice after intragastric administration. Finally, on the 14th day of the experiment, a necropsy was performed to observe any abnormality of the organs. In conclusion, in the coagulation and hemostasis tests, there were no statistical differences between the groups (P > 0.05), while there was a significant dose-response relationship, and the BT and CT were significantly shorter than those of the negative control group, which were comparable to the Yunnan Baiyao control group. Moreover, in the acute toxicity test, the median lethal dose of ethanol extract of O. corniculata was 6.0291 g/kg, with a 95% confidence interval of 5.3065–6.7829 mg/kg.  相似文献   
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宫颈癌严重威胁全球女性的生命健康,晚期宫颈癌治疗手段有限,5年生存率不到20%,是妇科肿瘤的巨大挑战。免疫治疗是晚期宫颈癌患者的重要治疗手段之一,包括免疫检查点抑制剂、治疗性疫苗和过继性T细胞免疫疗法等,但免疫治疗耐药性使部分患者无应答而效果不佳。因此,迫切需要深入研究和探讨免疫耐药的机制从而改善耐药,现归纳总结了近年有关宫颈癌中免疫耐药机制的相关研究,主要分为肿瘤内在因素和外在免疫环境改变等因素,并介绍针对免疫耐药提出的应对措施及进展。  相似文献   
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《Drug discovery today》2022,27(9):2551-2561
B cell lymphoma 2 (BCL2) overexpression in a range of human tumors is often related to chemotherapy resistance and poor prognosis. GC-rich regions upstream of the P1 promoter in human BCL2 can form G-quadruplex (G4) structures through the stacking of four Hoogsteen-paired guanine bases. Stabilizing the G4 fold implies the inhibition of BCL2 expression and, thus, small molecules that selectively bind to the G4 are promising anticancer candidates. In this review, we discuss the structural aspects, binding affinity, selectivity, and biological activity of well-characterized BCL2 G4 binding ligands in vitro and in vivo. We also explore future directions in the research and development of G4-based anticancer therapeutics.  相似文献   
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