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1.
中医学古籍中罕有关于“胰腺”的明确记载,缺乏直观、系统的理论论述。本文试图通过对各个时期具有代表性的医学典籍所记载内容的分析,结合现代解剖学相关理论,梳理中医学对胰腺实体解剖的认识过程。通过分析,笔者认为中医学对胰腺实体解剖的认识具有阶段性:①先秦两汉时期,存在胰腺实体解剖,但并非认为胰腺是脏器;②唐宋时期,胰腺实体解剖更加清晰,在医学上胰腺附属于脾,并非为独立的脏器;③明清时期,胰腺实体解剖明确,部分医家以独立脏器论之,出现“脾”、“胰”之争。中医学理论缺少对胰腺的单独论述,目前学界的主流观点多为“胰属脾”,线性归属以脾笼统代之略显单薄,不利于理论的丰富与发展。笔者认为胰腺藏象应独立于脾单独讨论,现代解剖学对胰腺命名同一,形态结构清楚,位置描述明确,可直接补充进中医学胰腺藏象(藏)理论中,为完善胰腺藏象理论搭建解剖学基础。  相似文献   
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Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
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MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
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miRNAs是一类长度约为20~25个核苷酸,参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员,在多种肿瘤中表达异常,其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此,miR-149有望成为新一类抗肿瘤治疗的靶点。  相似文献   
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患者男,64岁,因头颅增大、面部变长,颧骨隆起、下颌增大、双手掌肥厚、双手指粗短30余年,乳房肿物1年余就诊。患者30余年前无明显诱因出现渐进性手足增大,双手掌肥厚,嘴唇变厚,下颌增大,眉弓及颧骨突出,皮肤增厚,无乳腺增大、泌乳,未诊治……  相似文献   
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Antibody-mediated rejection is a major complication in renal transplantation. The pathologic manifestations of acute antibody-mediated rejection that has progressed to functional impairment of a renal transplant have been defined in clinical biopsy specimens. However, the initial stages of the process are difficult to resolve with the unavoidable variables of clinical studies. We devised a model of renal transplantation to elucidate the initial stages of humoral rejection. Kidneys were orthotopically allografted to immunodeficient mice. After perioperative inflammation subsided, donor-specific alloantibodies were passively transferred to the recipient. Within 1 hour after a single transfer of antibodies, C4d was deposited diffusely on capillaries, and von Willebrand factor released from endothelial cells coated intravascular platelet aggregates. Platelet-transported inflammatory mediators platelet factor 4 and serotonin accumulated in the graft at 100- to 1000-fold higher concentrations compared with other platelet-transported chemokines. Activated platelets that expressed P-selectin attached to vascular endothelium and macrophages. These intragraft inflammatory changes were accompanied by evidence of acute endothelial injury. Repeated transfers of alloantibodies over 1 week sustained high levels of platelet factor 4 and serotonin. Platelet depletion decreased platelet mediators and altered the accumulation of macrophages. These data indicate that platelets augment early inflammation in response to donor-specific antibodies and that platelet-derived mediators may be markers of evolving alloantibody responses.  相似文献   
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