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排序方式: 共有513条查询结果,搜索用时 15 毫秒
1.
目的探讨尿素酶型纤溶酶原激活物(urokinase-type plasminigen activator,uPA)、乙酰肝素酶(heparanase,HPA)在卵巢上皮癌和淋巴结转移癌中表达及其与肿瘤侵袭的关系。方法应用免疫组化SABC法,对65例卵巢上皮肿瘤手术标本进行uPA和HPA蛋白表达的测定。结果uPA、HPA在卵巢上皮癌中阳性表达率分别为66.7%、51.1%,其明显高于良性肿瘤及正常组织,有淋巴结转移的肿瘤的阳性表达率分别为78.1%、62.5%,无淋巴结转移的肿瘤阳性表达率分别为38.1%、23.1%,uPA和HPA高表达与卵巢癌侵袭和淋巴结转移关系密切(P<0.05)。uPA和HPA在卵巢癌中的表达无显著性差异(P>0.05)表达成正相关(r=0.724)。结论uPA和HPA蛋白的表达与卵巢癌的侵袭和转移有显著的相关性。 相似文献
2.
《Sport Management Review》2016,19(1):61-68
This case study is written for instructors of sport management courses focused on ethics and integrity-related issues in team environments. The case highlights the real world example of the University of Waterloo Warriors varsity football that, in 2010, experienced the most significant doping scandal in Canadian university sports history, with a total of nine anti-doping rule violations asserted through the Canadian Centre for Ethics in Sport. This case study also incorporates the findings of an independent review of the Waterloo football program in relation to the use of banned substances, and includes first-hand accounts from Bob Copeland who was the acting director of athletics. These findings are then interpreted in the context of relevant theory related to performance enhancing drugs (PEDs) use. Along with the findings of this review, which included interviews with athletes, coaches, and administrators, the case study provides important insights into ethical decision making processes and leadership structures in a team sport environment. Particular emphasis is placed on the role that individual cognitive antecedents and contextual organizational factors (i.e., policies, leadership, ethical climate, and infrastructure) play in ethical decision-making processes. 相似文献
3.
Mariusz Lipowski Małgorzata Lipowska Magdalena Jochimek Daniel Krokosz 《European Journal of Sport Science》2016,16(2):246-255
We hypothesised that resiliency may protect adolescents against risky behaviours, and that both the practicing of sports, and gender are moderating variables in relationships between resiliency and risky behaviours. The study included 18-year-old pupils from a selection of secondary schools (n = 556). A total of 188 individuals practiced competitive sports and the remaining 368 participants were non-athletes. The participants were examined with the Resiliency Assessment Scale for Children and Adolescents (SPP-18) and with a survey containing questions and statements related to high-risk “experiments with adulthood”. Adolescent athletes showed higher levels of resiliency than their peers. The power of the “Determination and Persistence in Action” effect on “Alcohol” scale differed significantly between male athletes and male non-athletes. Only in the athletes groups were higher scores on this scale reflected by lower values on the “Drugs” scale. Moreover, it is possible to observe differences in undertaking risky behaviour between male and female athletes. The analysis of risky sexual behaviour suggests that sport is a risk factor for men, and a protective factor for women. These data suggest that consistent prophylactic and psycho-educative activities, with a special attention to differences between genders, should be provided to all the adolescents, irrespective of their sport performance levels. 相似文献
4.
目的:探讨热休克蛋白70(HSP70)在人乳腺癌和胃癌中的表达及其意义。方法:应用免疫组织化学的方法对64例乳腺癌和55例胃癌组织中的HSP70进行检测。结果:(1)HSP70在乳腺癌和胃癌组织中的表达分别为78.13%.61.82%。(2)乳腺癌中HSP70的表达与乳腺癌的病理类型.淋巴结转移情况及年龄未发现显著差异(P〉0.05)。(3)胃癌中HSP70的表达与肿瘤浸润深度、淋巴结转移有密切关系(P〈0.05)。结论:HSP70在乳腺癌和胃癌中均呈较高水平表达.其中在胃癌中的表达与肿瘤浸润深度、恶性程度有密切关系,HSP70在乳腺癌和胃癌的发生发展中起重要作用。HSP70可能成为乳腺癌,胃癌的诊断指标之一。 相似文献
5.
Hari Prasad 《Resonance》2002,7(12):48-64
Berzelius, the Swedish chemist in 1807 introduced the term ‘organic compounds’ as those substances derived from once living
organisms (organized systems). Carbon exhibits the property of catenation (formation of chains) and forms a plethora of compounds
on earth. Silicon on the other hand which is placed below carbon in the periodic table does not exhibit this property. This
article is a brief account of some of the several reagents and classes of compounds encountered in organosilicon chemistry. 相似文献
6.
本文选择89年9月至90年1月住院病人39例,进行分组;另设对照组17例;采用国产WYX—402型原子吸收分光光度计(ASS)分别测得血清铜、锌及铜/锌比值。结果表明肝硬化组与正常组比较血清铜无显著差异(P>0.05),血清锌降低(P<0.05),铜/锌比值显著增高(P<0.001)。肝硬化并发肝癌组与肝硬化组比较,血清铜显著增高(P<0.001),血清锌无显著差异(P>0.05),铜/锌比值显著增高(P<0.001)。继发性肝癌组与原发性肝癌组比较,血清铜、锌及铜/锌比值均无显著性差异(P 值分别大于0.1;0.2)。研究表明,血清铜/锌比值 AFP测定有互补作用。 相似文献
7.
目的:建立一种定量、简单、快速、敏感的微小RNA(miRNA,miR)检测方法,并用其观察一些病理状态下有关miRNA的变化.方法:通过特殊设计的茎环结构的反转录引物,对miRNA进行反转录,然后用相应miRNA的正反向引物对该miRNA进行定量检测,观察重复性和特异性.用此法检测了人巨细胞病毒(HCMV)对滋养细胞(HPT-8)细胞内miR-513表达水平的影响,也检测了结直肠癌组织miR-145水平.结果:用该法扩增miRNA特异性强,结果重复性好,该法检测到HCMV感染对miR-513表达的梯度效应.也发现癌组织和正常组织间miR-145的表达有明显的差异.结论:用荧光定量PCR可以对微小RNA快速有效的检测,在临床工作中可得到很好的应用. 相似文献
8.
费歇判别法在乳房癌诊断中的应用 总被引:3,自引:0,他引:3
研究了乳房肿瘤的分类问题,通过对500个已知肿瘤性质(良性或恶性)细胞核的显微图像的10个量化特征进行统计分析,利用费歇判别法,建立了费歇判别模型,给出了判别准则,对未知乳房肿瘤性质的病例进行了成功的诊断;最后对变量进行了合理的缩减.本方法具有良好的实用性和操作性. 相似文献
9.
10.
Lakshmi Krishnamoorthy Elizabeth Zachariah P. G. Ramaswamy N. Anantha 《Indian journal of clinical biochemistry : IJCB》1994,9(1):37-39
Circulating levels of gonadotropins (FSH,LH), prolactin (PRL), estradiol and progesterone were measured by radioimmunoassay
in the sera of 60 patients with histopathologically proven breast cancer. 30 patients belonged to the post and 30 to the premenopausal
group. 30 healthy women, 15 each in the pre and post menopausal groups served as controls for the study.
Prolactin was elevated in 33% and 26% of pre and post menopausal breast cancer patients respectively. Lower levels of estradiol
and progesterone were observed during the luteal phase of the menstrual cycle in premenopausal breast cancer patients. Among
postmenopausal patients with breast cancer, LH was elevated in 32%, FSH in 15% and estradiol in 30% of the patients studied. 相似文献