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11.
Malaria, one of the most striking, re-emerging infectious diseases caused by the genus Plasmodium, places a huge burden on global healthcare systems. A major challenge in the control and eradication of malaria is the continuous emergence of increasingly widespread drug-resistant malaria, creating an urgent need to develop novel antimalarial agents. Chalcone derivatives are ubiquitous in nature and have become indispensable units in medicinal chemistry applications due to their diverse biological profiles. Many chalcone derivatives demonstrate potential in vitro and in vivo antimalarial activity, so chalcone could be a useful template for the development of novel antimalarial agents. This review covers the recent development of chalcone hybrids as antimalarial agents. The critical aspects of the design and structure–activity relationship of these compounds are also discussed.  相似文献   
12.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
13.
目的 分析H型高血压患者的舌面诊图像颜色参数特征,探讨H型高血压患者的舌诊、面诊变化规律。方法 运用上海中医药大学自行研制的Smart TCM-1型中医舌面一体仪,采集高血压患者舌面诊图像,提取特征参数,分析健康对照组、H型高血压组与非H型高血压组患者舌面颜色参数特征。结果 ①在舌色各项参数中,H型高血压组舌尖部R值、B值、V值均显著小于健康对照组(P < 0.01);非H型高血压组舌尖部B值显著小于健康对照组(P < 0.01),S值较健康对照组显著增大(P < 0.05);H型高血压组舌尖部R、V值均明显小于非H型高血压组(P < 0.05)。在舌苔各项参数中,H型高血压组舌中H值、V值均明显小于健康对照组(P < 0.05);非H型高血压组舌中V值、舌右V值均显著小于健康对照组(P < 0.01);H型高血压组舌中H值明显小于非H型高血压组(P < 0.05),右侧舌苔S值明显大于非H型高血压组(P < 0.05)。②H型高血压组面色参数鼻G值、下颌G值、口唇R值、口唇V值均明显小于健康对照组(P < 0.05);非H型高血压组前额H值、目眶H值、脸颊H值、鼻H值、下颌H值、整体H值均明显大于健康对照组(P < 0.05);H型高血压组前额H值、目眶G值、目眶H值、脸颊H值、鼻G值、鼻H值、下颌R值、下颌G值、下颌H值、下颌V值、口唇R值、口唇G值、口唇V值、整体R值、整体G值、整体H值、整体V值均明显小于非H型高血压组(P < 0.05)。结论 H型高血压患者苔色偏黄,以舌中部为主,且舌右侧黄苔积聚较明显;H型高血压患者面色为黄中带红,口唇、下颌部更为晦暗。H型高血压患者的舌、面诊特征参数的变化,与高血压病阳亢湿盛病机相符。  相似文献   
14.
15.
BackgroundArtificial insemination with the husband’s semen (AIH) is an economical and noninvasive method of infertility treatment. However, AIH’s pregnancy rate is much lower than in vitro fertilization (IVF) as its multiple and complex uncertainty factors. Semen quality has been one of the main factors which affect the pregnancy outcome of AIH.MethodsThe relevant parameters of 1,142 AIH cycles were retrospectively studied, including the general parameters and the semen quality parameters among clinical pregnancy, biochemical pregnancy, non-pregnancy group, age, infertility duration, infertility type, body mass index (BMI), cycle count, morphology in previously semen examination, and semen quality parameters on the day of AIH.ResultsThe statistically significant difference was only found on processed total non-forward and non-motile sperm count (N-TFMSC). The mean processed N-TFMSC in the biochemical pregnancy group was 6.37±4.27 million, significantly higher than the other two groups (vs. 4.40±3.15 million or vs. 4.48±3.60 million, P<0.05). The study was then divided into two groups according to processed N-TFMSC, Group 1 ≤5.0 million, and Group 2 >5.0 million. A statistical increase in biochemical pregnancy rate was observed when the processed N-TFMSC was >5.0 million (2.72% vs. 0.90%).ConclusionsProcessed N-TFMSC may be one of the independent factors on AIH’s outcome; it should be given equal attention the same as processed total forward motile sperm count (TFMSC).  相似文献   
16.
当利用放射线对胸部恶性肿瘤进行治疗时,位于纵隔的心脏会不可幸免受到照射,从而诱发放射性心脏损伤(radiation-induced heart disease, RIHD)。随着手术以及放化疗技术的提升,肿瘤患者生存时间得到延长,使得RIHD这一放疗远期并发症被越来越多的报道。因此,学者们对于RIHD的研究逐渐升温。目前国内外学者关于该疾病尚未形成统一的认识,临床上缺乏有效阻止其发生的方法。动物模型研究可为临床该疾病治疗及预防提供可靠证据,为此本文回顾分析近年来放射性心脏损伤动物模型实验研究情况,旨在为后续实验开展及临床应用提供参考。  相似文献   
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18.
There is very little evidence on the value of giving corticoids in cases of seawater drowning induced acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Therefore, this study aimed to investigate whether dexamethasone treatment can attenuate seawater instillation-induced acute lung injury in rabbits. Seawater (4 ml/kg body weight) was instilled into the lower trachea of ventilated, anesthetized rabbits. Then these rabbits were assigned randomly 20 min later to receive intravenous injection of 1mg/kg body weight of dexamethasone (dissolving in 2 ml of normal saline) or 2 ml of normal saline. All animals demonstrated immediate drops in arterial oxygen tension (PaO2) and the total thoracic compliance, which were significantly improved after 2 h of dexamethasone treatment. Histopathological study also indicated that dexamethasone treatment markedly attenuated lung histopathological changes, alveolar hemorrhage and inflammatory cells infiltration with evidence of decreasing of myeloperoxidase (MPO) activity and tumor necrosis factor-alpha (TNF-alpha) concentration in lung tissue. In addition, dexamethasone treatment reduced extravascular lung water and lung epithelial-endothelial barrier permeability, up-regulated the expression of surfactant protein-A (SP-A) and alpha-epithelial Na+ channel, and increased Na+/K+-adenosine triphosphatase (Na+/K+-ATPase) activity and Na+/K+-ATPase-alpha1 protein abundance. Thus, these data indicate that dexamethasone treatment might be of benefit in patients with seawater aspiration-induced ALI.  相似文献   
19.
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.  相似文献   
20.
目的探讨中原地区遗传性非息肉病性大肠癌(HNPCC)的表型特征,为制订适合我国国情的HNPCC遴选标准提供依据。方法对符合Am sterdam标准的8个家系37例患者的临床资料(A组),与随机抽调我院40例确切无家族史的大肠癌患者的临床资料(B组)进行对比分析。结果①发病年龄:A组平均46岁,B组62.6岁,平均提前16.6年;<50岁者:A组73%(27/37),B组30%(12/40),两组比较P<0.01;第1、2、3代平均发病年龄分别为69.2、46.9、34.6岁,逐代比较差异有统计学意义(P<0.05或P<0.01)。②发病部位:右半结肠A组73.2%(30/41),B组39.0%(16/41),两组比较P<0.05。③同时、异时多发大肠癌:A组8.1%(3/37),B组2.5%(1/40)。④大肠外癌:A组17.1%(7/41),B组0,两组比较P<0.05。⑤合并腺瘤:A组0,B组22.5%(9/40),两组比较P<0.05。⑥组织学类型:低分化腺癌A组69.7%(23/33),B组40%(16/40),两组比较P<0.05。结论中原地区HNPCC有其独特的临床特征,国际遴选标准不能完全适用于中国人,制定适合我国国情的HNPCC遴选标准确有必要。  相似文献   
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