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11.
随着腔镜技术的进一步发展以及微创理念应用于结直肠外科疾病的诊治中,结直肠相关疾病的诊治发生了翻天覆地的变化。由传统的经腹手术到腹腔镜手术、经自然腔道手术,再到经自然腔道取标本手术(NOSES),结直肠疾病的外科诊治在微创领域取得了巨大成果。NOSES技术是目前结直肠外科在微创领域前沿的手术方式之一,它通过经直肠、阴道取标本来避免了腹壁的辅助取标本切口,从而将结直肠外科手术进一步微创化。NOSES技术集传统腹腔镜手术的优势与现代微创外科的理念于一体,它在确保手术效果的基础上集中体现了微创、加速康复外科、功能外科、"无疤"等理念的特点。本文主要就国内外各中心开展NOSES技术在结直肠外科诊治开展中的相关经验、心得和体会进行综述。  相似文献   
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A pathological feature in atherosclerosis is the dysfunction and death of vascular endothelial cells (EC). Oxidized low‐density lipoprotein (LDL), known to accumulate in the atherosclerotic arterial walls, impairs endothelium‐dependent relaxation and causes EC apoptosis. A major bioactive ingredient of the oxidized LDL is lysophosphatidylcholine (LPC), which at higher concentrations causes apoptosis and necrosis in various EC. There is hitherto no report on LPC‐induced cytotoxicity in brain EC. In this work, we found that LPC caused cytosolic Ca2+ overload, mitochondrial membrane potential decrease, p38 activation, caspase 3 activation and eventually apoptotic death in mouse cerebral bEND.3 EC. In contrast to reported reactive oxygen species (ROS) generation by LPC in other EC, LPC did not trigger ROS formation in bEND.3 cells. Pharmacological inhibition of p38 alleviated LPC‐inflicted cell death. We examined whether heparin could be cytoprotective: although it could not suppress LPC‐triggered Ca2+ signal, p38 activation and mitochondrial membrane potential drop, it did suppress LPC‐induced caspase 3 activation and alleviate LPC‐inflicted cytotoxicity. Our data suggest LPC apoptotic death mechanisms in bEND.3 might involve mitochondrial membrane potential decrease and p38 activation. Heparin is protective against LPC cytotoxicity and might intervene steps between mitochondrial membrane potential drop/p38 activation and caspase 3 activation.  相似文献   
13.
涎腺导管内癌(intraductal carcinoma,IDC)是一种主要发生在腮腺,在导管内或囊内生长为主的罕见肿瘤,但也可伴浸润性生长,生物学行为相对惰性。具有独特的形态学、免疫表型及分子遗传学特征。主要包括4种亚型:闰管型、顶浆分泌型、闰管-顶浆分泌混合型和嗜酸型。闰管型多数存在NCOA4-RET融合,个别存在STRN-ALK融合;混合型存在TRIM27-RET融合,顶浆分泌型具有PIK3CA和HRAS突变或TP53缺失;嗜酸型具有TRIM33-RET融合或BRAF V600E突变。目前多数观点认为与涎腺导管癌不同,即使存在浸润,仍具有良好的预后,罕见复发和淋巴结转移,无远处转移。因此精准诊断对于临床治疗的选择极其重要。  相似文献   
14.
文章回顾中医体质研究40年来在6大理论创新、3大技术创新、4大转化应用、2大学术平台方面取得的辉煌成就。展望未来,中医体质研究将积极策应国家需求,进一步发挥其原创优势、深化理论研究、完善技术方法、加快平台建设、提升服务能力,为实施“健康中国”战略作贡献。  相似文献   
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16.
目的  测评医学生的共情能力现状,探讨人格特质对其共情能力的影响,为培养医学生的共情能力提供对策。方法  以上海市3所高校临床医学专业学生为研究对象,采用班级整群抽样的方式进行问卷调研。采用杰斐逊共情量表-医学生版(JSPE-S)和大五人格量表(NEO-FFI)分别评估医学生的共情和人格特质。结果  共发放问卷2 020份,回收有效问卷1 958份,有效率为96.93%。医学生的共情能力总分均值为(103.24±14.35)。共情能力总分与大五人格中的“外向性”“开放性”“宜人性”“严谨性”维度呈显著正相关(r=0.154~0.406, P<0.01),与大五人格中的“神经质”维度呈显著负相关(r=-0.175, P<0.01)。分层回归结果表明:“共情重要性”和“大五人格”量表的5个维度进入回归方程。其中,人格因素占可解释方差变异量的16.2%(P<0.01)。结论  我国医学生的共情能力低于国外医学生,重视人格特质的塑造有助于提高其共情能力。  相似文献   
17.
Calculus bovis is commonly used for the treatment of stroke in traditional Chinese medicine. Hyodeoxycholic acid(HDCA) is a bioactive compound extracted from calculus bovis. When combined with cholic acid, baicalin and jas-minoidin, HDCA prevents hypoxia-reoxygenation-induced brain injury by suppressing endoplasmic reticulum stress-mediated apoptotic signaling. However, the effects of HDCA in ischemic stroke injury have not yet been studied. Neurovascular unit(NVU) dysfunction occurs in ischemic stroke. Therefore, in this study, we investigated the effects of HDCA on the NVU under ischemic conditions in vitro. We co-cultured primary brain microvascular endothelial cells, neurons and astrocytes using a transwell chamber co-culture system. The NVU was pre-treated with 10.16 or 2.54 μg/mL HDCA for 24 hours before exposure to oxygen-glucose deprivation for 1 hour. The cell counting kit-8 assay was used to detect cell activity. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling were used to assess apoptosis. Enzyme-linked immunosorbent assay was used to measure the expression levels of inflammatory cytokines, including interleukin-1β, interleukin-6 and tumor necrosis factor-α, and neurotrophic factors, including brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor. Oxidative stress-related factors, such as superoxide dismutase, nitric oxide, malondialdehyde and γ-glutamyltransferase, were measured using kits. Pretreatment with HDCA significantly decreased blood-brain barrier permeability and neuronal apoptosis, significantly increased transendothelial electrical resistance and γ-glutamyltransferase activity, attenuated oxidative stress damage and the release of inflammatory cytokines, and increased brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor expression. Our findings suggest that HDCA maintains NVU morphological integrity and function by modulating inflammation, oxidation stress, apoptosis, and the expression of neurotrophic factors. Therefore, HDCA may have therapeutic potential in the clinical management of ischemic stroke. This study was approved by the Ethics Committee of Experimental Animals of Beijing University of Chinese Medicine(approval No. BUCM-3-2016040201-2003) in April 2016.  相似文献   
18.
Photobiomodulation (PBM) therapy is based on the exposure of biological tissues to low‐level laser light (coherent light) or light‐emitting diodes (LEDs; noncoherent light), leading to the modulation of cellular functions, such as proliferation and migration, which result in tissue regeneration. PBM therapy has important clinical applications in regenerative medicine. Vitiligo is an acquired depigmentary disorder resulting from disappearance of functional melanocytes in the involved skin. Vitiligo repigmentation depends on available melanocytes derived from (a) melanocyte stem cells located in the bulge area of hair follicles and (b) the epidermis at the lesional borders, which contains a pool of functional melanocytes. Since follicular melanoblasts (MBs) are derived from the melanocyte stem cells residing at the bulge area of hair follicle, the process of vitiligo repigmentation presents a research model for studying the regenerative effect of PBM therapy. Previous reports have shown favourable response for treatment of vitiligo with a low‐energy helium‐neon (He‐Ne) laser. This review focuses on the molecular events that took place during the repigmentation process of vitiligo triggered by He‐Ne laser (632.8 nm, red light). Monochromatic radiation in the visible and infrared A (IRA) range sustains matrix metalloproteinase (MMP), improves mitochondrial function, and increases adenosine triphosphate (ATP) synthesis and O2 consumption, which lead to cellular regenerative pathways. Cytochrome c oxidase in the mitochondria was reported to be the photoacceptor upon which He‐Ne laser exerts its effects. Mitochondrial retrograde signalling is responsible for the cellular events by red light. This review shows that He‐Ne laser initiated mitochondrial retrograde signalling via a Ca2+‐dependent cascade. The impact on cytochrome c oxidase within the mitochondria, an event that results in activation of CREB (cyclic‐AMP response element binding protein)‐related cascade, is responsible for the He‐Ne laser promoting functional development at different stages of MBs and boosting functional melanocytes. He‐Ne laser irradiation induced (a) melanocyte stem cell differentiation; (b) immature outer root sheath MB migration; (c) differentiated outer root sheath MB melanogenesis and migration; and (d) perilesional melanocyte migration and proliferation. These photobiomodulation effects result in perifollocular and marginal repigmentation in vitiligo.  相似文献   
19.
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   
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