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1.
Grass shrimp, Palaemonetes pugio, were exposed for 1 month to subacute concentrations of hexavalent chromium (0.5, 1.0, 2.0, 4.0 ppm) after which the gills, midgut, hepatopancreas, and antennal glands were examined for histopathological and ultrastructural changes. Pathological changes were greatest in the antennal glands, followed by hepatopancreas, gills, and midgut. Severe changes occurred in some shrimp, even at 0.5 ppm chromium. Cells of all tissues frequently had both swollen mitochondria and rough endoplasmic reticulum. Small, spherical or ring-like intranuclear inclusions, possibly indicative of cellular hyperactivity or manifestions of chromium and/or protein complexes, were most prevalent in the hepatopancreas and antennal glands but also occurred in the midgut and gills. Other major degenerative changes in the antennal glands were restricted to the labyrinth and included diminution of basal plasmalemmal infoldings and cytoplasmic density, nuclear hypertrophy followed by widespread nuclear pyknosis and epithelial desquamation. In severely altered hepatopancreas hypertrophy was indicated for the basal laminae, nuclei, and possibly for the nucleoli. There was an apparent reduction in mitotic events and many observed mitotic nuclei were abnormal. Abnormal midgut hypertrophy was present in only 8 of 20 examined shrimp, exposed to 0.5 and 1 ppm chromium. Further, the gills of only 10 of the 40 examined chromium-exposed shrimp possessed abnormal features detectable with ligh microscopy. Ultrastructural analysis of the latter indicated an increase in lysosomes and a decrease in cytoplasmic density. In addition, there was a pronounced diminution in the degree of lamellar, subcuticular plasmalemmal infolding. This latter feature is postulated to be a mechanism for the regulation of chromium influx. Possible explanations for most observed alterations in the above tissues are proposed.  相似文献   
2.
目的 探讨微信平台临床病理讨论会教学效果。方法 将66名2015级医学检验技术专业的学生采用信封法随机分成两组,每组各33名,设定第一组为传统教学即为对照组,第二组为微信平台病理讨论会教学即为实验组,并选取《病理学》中的消化系统疾病章节的消化性溃疡和病毒性肝炎两节课程,进行教学实验。通过成绩考核(包括理论基本知识以及实验技能)、问卷调查进行教学效果评价,探讨微信平台病理讨论会模式在病理学课程中理论和实验教学上的效果。结果 通过对比分析,证实微信平台病理讨论会模式教学与传统教学模式成绩考核无显著性差异。微信平台病理讨论会有助于提高学生查阅资料、分工协作能力,但对提高学生的学习兴趣、动手、分析和解决问题能力,与传统教学模式比较,并无差异。实验组学生69.7%(23/33)认可这种微信平台病理讨论会模式的教学法。结论 微信平台临床病理讨论会有助于学生早期接触临床,学习效果不比传统教学方法差。  相似文献   
3.
Cardiac vascular microenvironment is crucial for cardiac remodelling during the process of heart failure. Sphingosine 1‐phosphate (S1P) tightly regulates vascular homeostasis via its receptor, S1pr1. We therefore hypothesize that endothelial S1pr1 might be involved in pathological cardiac remodelling. In this study, heart failure was induced by transverse aortic constriction (TAC) operation. S1pr1 expression is significantly increased in microvascular endothelial cells (ECs) of post‐TAC hearts. Endothelial‐specific deletion of S1pr1 significantly aggravated cardiac dysfunction and deteriorated cardiac hypertrophy and fibrosis in myocardium. In vitro experiments demonstrated that S1P/S1pr1 praxis activated AKT/eNOS signalling pathway, leading to more production of nitric oxide (NO), which is an essential cardiac protective factor. Inhibition of AKT/eNOS pathway reversed the inhibitory effect of EC‐S1pr1‐overexpression on angiotensin II (AngII)‐induced cardiomyocyte (CM) hypertrophy, as well as on TGF‐β‐mediated cardiac fibroblast proliferation and transformation towards myofibroblasts. Finally, pharmacological activation of S1pr1 ameliorated TAC‐induced cardiac hypertrophy and fibrosis, leading to an improvement in cardiac function. Together, our results suggest that EC‐S1pr1 might prevent the development of pressure overload‐induced heart failure via AKT/eNOS pathway, and thus pharmacological activation of S1pr1 or EC‐targeting S1pr1‐AKT‐eNOS pathway could provide a future novel therapy to improve cardiac function during heart failure development.  相似文献   
4.
摘要 目的:研究乳腺癌患者新辅助化疗(NAC)后达到腋窝淋巴结病理完全缓解(pathologic complete response of axillary,apCR)的远期生存以及影响远期生存的相关因素分析。方法:回顾性分析哈尔滨医科大学附属肿瘤医院乳腺外科624例乳腺癌患者的住院资料,采用Kaplan-Meier生存分析以及COX回归分析的统计学分析方法,分析乳腺癌患者新辅助化疗后腋窝状态与无病生存(DFS)和总生存(OS)的关系及影响apCR预后的因素。结果:apCR与非apCR患者比较DFS(P=0.013)和OS(P=0.037)差异具有统计学意义,apCR患者的预后与年龄、肿瘤大小、肿瘤受体状态、HER-2、ki67状态、分子分型等因素无相关性。结论:与非apCR患者相比,乳腺癌患者新辅助化疗后apCR患者预后更好,但apCR患者预后良好的因素仍需进一步临床试验分析。  相似文献   
5.
Although Serbia is recognized as an endemic country for echinococcosis, no information about precise incidence in humans has been available. The aim of this study was to investigate the skeletal manifestations of hydatid disease in Serbia. This retrospective study was conducted by reviewing the medical database of Institute for Pathology (Faculty of Medicine in Belgrade), a reference institution for bone pathology in Serbia. We reported a total of 41 patients with bone cystic echinococcosis (CE) during the study period. The mean age of 41 patients was 40.9±18.8 years. In 39% of patients, the fracture line was the only visible radiological sign, followed by cyst and tumefaction. The spine was the most commonly involved skeletal site (55.8%), followed by the femur (18.6%), pelvis (13.9%), humerus (7.0%), rib (2.3%), and tibia (2.3%). Pain was the symptom in 41.5% of patients, while some patients demonstrated complications such as paraplegia (22.0%), pathologic fracture (48.8%), and scoliosis (9.8%). The pathological fracture most frequently affected the spine (75.0%) followed by the femur (20.0%) and tibia (5.0%). However, 19.5% of patients didn''t develop any complication or symptom. In this study, we showed that bone CE is not uncommon in Serbian population. As reported in the literature, therapy of bone CE is controversial and its results are poor. In order to improve the therapy outcome, early diagnosis, before symptoms and complications occur, can be contributive.  相似文献   
6.
目的:探讨甲基化Sept9基因在结直肠癌患者血浆中的表达及临床意义。方法:选择2015年1月~2017年3月经陕西省人民医院病理证实的结直肠癌患者87例(结直肠癌组)、结直肠息肉患者79例(结直肠息肉组)、健康体检者93例(健康对照组)作为研究对象,采用实时荧光定量聚合酶链式反应(PCR)技术检测其外周血血浆Sept9基因甲基化情况,比较三组甲基化Sept9基因阳性表达率,分析甲基化Sept9基因阳性表达与结直肠癌病理特征的关系。结果:血浆甲基化Sept9基因在结直肠癌组、结直肠息肉组、健康对照组的阳性表达率分别为71.26%(62/87)、5.06%(4/79)、3.23%(3/93),差异有统计学意义(P0.05);血浆甲基化Sept9基因阳性表达与结直肠癌患者的性别、年龄、肿瘤部位、病理分型、血管侵犯、神经侵犯无关(P0.05),与肿瘤最大径、浸润深度、分化程度、淋巴结转移、TNM分期有关(P0.05);结直肠癌患者血浆甲基化Sept9基因阳性表达率为71.26%(62/87),高于血清CEA的54.02%(47/87)、CA199的35.63%(31/87)、CA724的33.33%(29/87)、CA125的21.84%(19/87),差异有统计学意义(P0.05)。结论:结直肠癌患者外周血血浆甲基化Sept9基因呈高表达状态,早期检测甲基化Sept9基因表达水平在结直肠癌的诊断及病情评估中有重要意义。  相似文献   
7.
美洲大蠊提取物具有显著的抗肿瘤、抗菌和抗肝纤维化等作用,但是,其对肺脏抗氧化应激效果的研究未见报道,本文主要探讨美洲大蠊乙醇提取物对熏烟小鼠血液和肺脏抗氧化应激的效果.选用雌性KM小鼠28只,随机分为对照组、熏烟组、低剂量和高剂量美洲大蠊醇提物组各7只,除对照组灌胃生理盐水外,其他各组每天中午和下午采用烟熏处理,持续3...  相似文献   
8.
To determine the roles of different ocular tissues in the development of the human fetal neuroretina, a study ethically and technically impossible in human subjects, human embryonic and fetal retinas were heterotopically implanted into nude mice. Ninety-five eyeballs were obtained from legally aborted 6- to 7-week-old embryos or 8- to 10-week-old fetuses. Ten isolated neuroretinas with vitreous but without pigment epithelium, 20 half-eyeballs and 70 intact eyeballs, of which 12 had a thick layer of periocular tissue, were microsurgically grafted. Five intact eyeballs were used for reference. Over a period of 1-245 days, all of the grafts were removed for light and electron microscopy observations. All of the isolated neuroretinas had disappeared by the second day after transplantation. Grafts of the posterior section of the eyeball contained only some clusters of pigment epithelium, occasionally covered with undifferentiated neuroretinal cells. Grafts of the retrolental section of the eyeball contained small areas of dysplasic neuroretina with folds and rosettes. Grafts of the 70 intact eyeballs were successful, but only 26 showed normal histological organization of the choriocapillaris, the retinal pigment epithelium and the neuroretina in the posterior part of the posterior chamber. Photoreceptor differentiation was evident in these retinas after approximately 80 days of transplantation and was complete after 166 days. Their anterior part was always dysplasic, with occasional ciliary differentiation. Twenty-three grafted eyeballs had a dysplasic neuroretina with folds, rosettes and necrotized areas. Twenty-one were atrophic, 12 of which were the eyeballs grafted with periocular tissue. These results demonstrate the role of the fetal mesenchyme and pigment epithelium in the rapid revascularization, and subsequent survival and tissue organization, of the neuroretina. The stratified development of the neuroretina required a thin mesenchymal environment for revascularization of the graft by human vasculogenesis or neoangiogenesis and a normal retinal pigment epithelium for normal neuroretinal differentiation. When these conditions were not satisfied, the neuroretina disappeared or was dysplasic, partly necrotized or atrophic. This model might prove useful for a number of therapeutic or clinical studies.  相似文献   
9.
史悦  许争争  鲁欢  慈维敏 《遗传》2018,40(11):1033-1038
准确评估肿瘤的病理亚型对诊断、治疗和预后至关重要。以往病理亚型的诊断主要依赖HE染色法和免疫组织化学法,而随着测序技术的不断发展,对患者进行基因型和表型特点的个体分析成为可能,将肿瘤病理分型与基因分型结合用于疾病分型、诊治选择和疗效判断的精准医学研究逐渐兴起。不同病理亚型的肿瘤细胞来源、致癌因素和临床表型均不尽相同,其在基因组上会留下特异“印迹”,即突变特征。本研究通过整合癌症基因组数据库(The Cancer Genome Atlas, TCGA)中肾癌、肺癌和食管癌的外显子测序数据,分别对3种肿瘤通过肿瘤基因突变特征进行肿瘤病理分型聚类和预测。首先通过非监督聚类方法将3种肿瘤分别按照24种突变特征进行聚类分析,其次通过随机森林法从24种突变特征中进一步选择对于区分不同病理亚型有显著性的突变特征并进行聚类分析,构建突变特征对3种肿瘤病理亚型的分型模型。在肾癌中,该模型准确率达到了100% (95% confidence interval (CI): 0.93~1.00),肺癌和食管癌中分别达到了78% (95% CI: 0.66~0.86)和84% (95% CI: 0.60~0.97)。以上研究结果表明,突变特征作为新型分子标记物,对肿瘤的病理分型、诊断,尤其是早诊具有一定的参考意义。  相似文献   
10.
摘要 目的:探讨血清微小核糖核酸(miRNA)-141-3p、miR-150-5p与鼻咽癌(NPC)患者临床病理特征和放疗敏感性的关系。方法:收集2019年1月~2022年7月在我院接受放疗的92例NPC患者为NPC组,根据放疗疗效分为抵抗组和敏感组,另选取同期80名在我院体检的健康志愿者为对照组。比较对照组、NPC组血清miR-141-3p、miR-150-5p表达。分析NPC患者血清miR-141-3p、miR-150-5p表达与临床病理特征的关系。利用单因素和多因素Logistic回归分析NPC患者放疗抵抗的影响因素。结果:与对照组比较,NPC组血清miR-141-3p表达升高,miR-150-5p表达降低(P<0.05)。NPC患者血清miR-141-3p、miR-150-5p表达在不同分化程度、TNM分期和淋巴结转移中比较有差异(P<0.05)。92例NPC患者放疗抵抗发生率为22.83%(21/92)。单因素分析显示,抵抗组TNM分期Ⅲ~Ⅳa期和miR-141-3p ≥ 2.60比例高于敏感组,miR-150-5p ≥ 0.80比例低于敏感组(P<0.05)。多因素Logistic回归分析显示,miR-141-3p ≥ 2.60为NPC患者放疗抵抗的独立危险因素,miR-150-5p ≥ 0.80为独立保护因素(P<0.05)。结论:NPC患者血清miR-141-3p高表达,miR-150-5p低表达,与分化程度、TNM分期、淋巴结转移和放疗敏感性有关,有望成为NPC患者放疗抵抗的评价指标。  相似文献   
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