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1.
目的:观察TNF-α基因启动子区-308位核苷酸多态性基因型在肺癌和对照人群中的分布,以及这种多态性对该基因表达和细胞凋亡的影响。方法:PER-RFLP分析112例肺癌和99例正常人的TNF-α基因启动子区-308位核苷酸多态性,TNF-α-308*G等位基因记做TNF-α1,TNF-α-308*A等位基因记做TNF- α2。免疫组织化学方法检测肺癌组织中TNF-α的表达,比较不同基因型肺癌病例的标本之间TNF-α基因表达的差异性。TUNEL法检测肺癌组织中细胞凋亡,并对比分析TNF-α-308位核苷酸多态性及其对肺癌组织中TNF -α表达和不同类型细胞凋亡的影响。结果:肺癌组与对照组的基因型分布为TNF-α1/1(52.7%、46.5%)。 TNF-α1/2(35.7%、48.5%),TNF-α2/2(11.6%、5.1%);等位基因频率为TNF-α1(70.5%、70.7%),TNF- α2(29.5%、29.3%),组间没有显著性差异,P>0.05。两种基因型个体在TNF-α基因表达上,TNF-α2/2基因型个体高于TNF-α1/1基因型的个体,两者差异显著,P<0.01。TNF-α表达的高低与癌细胞凋亡有比较明确的关系,TNF-α表达高的病例,肺癌细胞凋亡也多,与表达低的病例之间有明显差异,P<0.01。TNF-α表达的高低与间质细胞凋亡之间没有明确的关系。间质细胞平均凋亡指数在高、低分化的肺癌中分别为3.4±0.4和 3.1±0.5,组间没有显著性差异,P>0.015;癌细胞的平均凋亡指数在高、低分化的肺癌中分别为2.4±0.3和 1.7±0.4,两组间有显著性差异,P<0.05,,结论:TNF-α-308位核苷酸的多态性基因型在肺癌和正常人中的分布之间没有明显差别,这种多态性可能不是肺癌易感的遗传因素。但这种多态性与该基因的表达有关。TNF-α高表达肺癌细胞凋亡较多,间质细胞凋亡与TNF-α表达的高低变化之间没有明确的关系。在高分化的肺癌中, TNF-α表达较高,癌细胞凋亡也多,TNF-α-308位核苷酸的多态性可能与了肺癌的分化有关。  相似文献   
2.
为探讨不同家禽红细胞对禽流感血清抗体检测的影响,对不同家禽的禽流感阳性血清分别经不同方法处理后,做了一系列对比试验。结果发现,经受体破坏酶(RDE)处理后,虽然可以消除异种家禽血清对异种家禽红细胞的非特异性凝集作用的影响,但因处理复杂,费用高,不宜推广应用;经鸡红细胞吸附处理,可明显降低水禽血清对异种红细胞的非特异性凝集作用,但处理费时;而用水禽红细胞检测同种水禽的禽流感血清抗体,可以有效去除血清非特异性凝集的影响,且更能准确地反映水禽经禽流感疫苗免疫后的抗体水平。因而,应选用与宿主来源相同的红细胞悬液检测水禽禽流感血清抗体。  相似文献   
3.
This study presents a series of 16 carriers of hemoglobin S (HbS) who died during various circumstances. Many of the cases were associated with mild to moderate exertion. The onset and/or duration of symptoms varied from a few minutes to several hours with many displaying a prolonged lucid interval with stable vital signs. Despite seeking medical treatment, sickle cell trait-related micro-occlusive crisis was never considered in the differential diagnosis. Several cases were associated with sudden death. In those deaths which were delayed, high anion gap and uncompensated metabolic acidosis were typical and were not heat related. Also characteristic were large increases in creatine kinase, alanine aminotransferase, and aspartate aminotransferase along with myoglobinemia. Although the antemortem diagnosis of rhabdomyolysis was made, the underlying cause was never deduced by the clinicians. The sickling found at autopsy is not always a postmortem artifact, and in the right circumstances can be diagnostic.  相似文献   
4.
目的探讨Stat1是否参与弥漫性轴索损伤(diffuse axonal injury,DAI)后神经细胞凋亡的病理生理过程。方法应用自由落体撞击模型复制大鼠DAI模型,分为正常对照组、假手术组和打击后不同时间组(6、12、24、48、72h,5d和10d)。采用HE染色和镀银染色观察大鼠脑组织的病理改变,用流式细胞检测脑组织中脑细胞的凋亡率,RT-PCR法测定脑组织中bax和bcl-2的表达变化,免疫组织化学法测定脑组织中不同脑区727位丝氨酸磷酸化的信号转导与转录激活子1(Phospho-Ser727 Stat1)的表达情况。结果DAI后HE染色未见脑挫裂伤,镀银染色可见神经轴索扭曲肿胀,个别断端膨大形成轴缩球;损伤组脑细胞的凋亡率和脑组织中bax和bcl-2 cDNA扩增产物的比值24h达到最大值,随后下降;不同脑区Phospho-Ser727 Stat1表达升高,24h达峰后下降,至10d较对照组仍有显著差异;阳性细胞主要是神经元,在不同脑区也有一定量的神经胶质细胞阳性表达。脑组织中Phospho-Ser727 Stat1表达变化与bax和bcl-2的cDNA扩增产物比值的变化具有正相关性,相关系数r为0.921。结论大鼠DAI后Stat1的激活和损伤后脑细胞的凋亡有关,应与损伤后二次打击有关。  相似文献   
5.
毒鼠强诱导细胞DNA损伤的彗星电泳检测   总被引:1,自引:0,他引:1  
目的 研究毒鼠强对小鼠淋巴细胞和脑细胞DNA的损伤作用。方法 分离健康小鼠的淋巴细胞和脑细胞 ,以彗星电泳的方法测定不同浓度毒鼠强处理后的细胞DNA损伤。结果  1/2 0~ 1/2LD50 剂量组的毒鼠强均可引起淋巴细胞和脑细胞不同程度的DNA损伤 ,与对照组呈极显著性差异 (P <0 0 0 1)。结论 毒鼠强引起细胞DNA断裂损伤 ,并呈现明显的剂量 -效应关系。  相似文献   
6.
灌服毒鼠强诱导大鼠细胞DNA的损伤研究   总被引:1,自引:0,他引:1  
Zhu CH  Liu Y  Deng LB 《法医学杂志》2005,21(1):27-29
目的研究毒鼠强体内染毒后,毒鼠强对大鼠脑细胞、心肌细胞、淋巴细胞DNA的损伤作用。方法选择健康Sprague-Dawley大白鼠20只,分成5组,每组4只,采用灌胃方法使大鼠毒鼠强体内染毒,按0.2,0.1,0.05,0.01mg·kg-1制作大鼠毒鼠强中毒模型,并以灌服生理盐水的健康大鼠为对照,分离实验大鼠的淋巴细胞、心肌细胞和脑细胞,用彗星电泳的方法测定不同浓度毒鼠强中毒后的细胞DNA损伤。结果0.2,0.1,0.05,0.01mg·kg-1剂量组的毒鼠强均可引起大鼠的淋巴细胞、心肌细胞和脑细胞DNA损伤,均与对照组差异有显著性(P<0.01)。结论毒鼠强诱导体内细胞DNA损伤可能是毒鼠强毒性作用机制之一。  相似文献   
7.
    
Each year hundreds of thousands of males begin long-term androgen deprivation therapy (ADT), i.e. chemical or surgical castration, to slow the progress of prostate cancer. ADT causes loss of muscle mass and body hair; genital shrinkage and erectile dysfunction; variable amounts of breast growth and the development of a characteristically post-menopausal female pattern of fat distribution. ADT also changes mood and affect, most conspicuously seen as increased emotionality and depressed libido. Given these changes, it is not surprising that many patients on ADT no longer feel ‘manly’, yet do not experience themselves as women. For many, this gender liminality is psychologically and socially traumatic. Faced with these difficulties, how can castrated males understand themselves in a positive way?

We explore the idea that some men may benefit from embracing the alternative gender identity of ‘eunuch’. Unfortunately, due in part to the historic practice of forced castration, the word ‘eunuch’ is now largely pejorative, although it is the correct biological term for a castrated male. We examine the benefits and risks of contemporary castrated males accepting this identity to help them adapt to the changes they experience.  相似文献   
8.
Liu Z  Wu W  Zhou Y 《法医学杂志》1998,14(1):16-17
探讨人体组织ABO血型检测方法。对已知ABO血型尸体的不同组织,用红细胞粘连试验、吸收—抑制试验和吸收-解离试验进行ABO血型测定。12例尸体的16种组织中均检出与尸体血痕相同的ABH物质。对不同温度保存的组织块进行ABH物质检测的结果显示,4℃保存的组织ABH物质的检出时间长于室温,空腔脏器的检出时间短于实质脏器。三种方法中,红细胞粘连试验简单易行,适用于基层单位,吸收-抑制试验用于组织块的测定时优于吸收-解高试验。  相似文献   
9.
This paper analyzes how Caribbean-American poet and activist Audre Lorde textualizes the experience of breast cancer in her journals. Lorde confronts the narrative of the female body provided by the biomedical approach and challenges the passive role she is expected to play as a sick person. She deplores misinformation to patients and the insistence on reconstructive surgery after a mastectomy. Lorde denounces the discursive aggression toward women that is the result of the hidden patriarchal impositions insidiously operating within medical practices. She believes medical discourse has often been used to implement many of the precepts that underlie a male-centered society, shaping the gendering of women in line with a patriarchal worldview. This paper examines how Lorde faced with such a hostile situation, managed to overcome it, by speaking up and putting her fears and her hopes into words. Her personal diaries, The Cancer Journals (1980) and A Burst of Light (1988), constitute today a fundamental point of reference and an important contribution to the feminist cause.  相似文献   
10.
    
Diaphragmatic defects are a relatively common and benign finding in adults which may be congenital or secondarily acquired. The case files at Forensic Sciences South Australia were reviewed over a 10‐year period from July 2005 to June 2015 for all adult (>17 years) cases in which diaphragmatic hernias were identified at postmortem examination that had either caused or contributed to death. Five cases were found: age range 49–90 years (average 67.2 years); male:female ratio 2:3. Herniated organs included the stomach (N = 3), small (N = 3) and large intestines (N = 2). Mechanisms of death involved lung compression with respiratory failure and/or mediastinal shift, and vascular compromise with gastric or intestinal infarction and/or perforation. Diaphragmatic hernias may not be identified until the time of autopsy and may be quite complex entities to evaluate due to a lack of clinical history and to difficulties in determining their origin and possible contributions to mechanisms of death.  相似文献   
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