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991.
992.
为了探讨WPBL教学法在"微生物学检验"教学中的应用效果,对本院2008级检验医学专业66名学生进行分组教学,实验组采用WPBL教学法,对照组采用传统教学法。课后对2组学生进行理论测试,同时对实验组进行问卷调查。经统计,实验组的测试成绩明显优于对照组(P0.01),且2组学生测试成绩的及格率差异有统计学意义(P0.05);问卷调查显示90%以上的学生对WPBL教学法感兴趣,认为WPBL教学法能提高学习兴趣、自学能力和分析解决问题的能力。从结果看,WPBL教学法能够提高"微生物学检验"教学质量。 相似文献
993.
蹄蝠科的核型进化:比较染色体涂色、G带和C带分析(英文) 总被引:1,自引:0,他引:1
与其姐妹科(菊头蝠科)相比,蹄蝠科的细胞遗传学研究较少。迄今为止,仅少数蹄蝠科几个物种有高分辨率的G带核型报道,且有关该科核型进化的大多数结论都是基于常规Giemsa染色研究而得。该研究利用三叶小蹄蝠的染色体特异探针,通过比较染色体涂色、G和C显带,建立了5种蹄蝠的染色体同源性图谱,并探讨了它们同源染色体间的G和C带异同。结果表明:罗伯逊易位、臂内倒位以及异染色质的扩增可能是蹄蝠科物种核型进化的主要机制。通过对这5种蹄蝠物种及其外群物种之间的同源染色体片段的比较分析,作者推测蹄蝠科的祖先核型并不像先前认为的全由端着丝粒染色体组成,而应该含有中着丝粒染色体。 相似文献
994.
Khadijeh Bijangi-Vishehsaraei Mohammad Reza Saadatzadeh Su Huang Michael P. Murphy Ahmad R. Safa 《Molecular and cellular biochemistry》2010,342(1-2):133-142
Cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor for the tumor necrosis factor-related apoptosis-inducing ligand TRAIL and in drug resistance in human malignancies. c-FLIP is an antagonist of caspases-8 and -10, which inhibits apoptosis and is expressed as long (c-FLIPL) and short (c-FLIPS) splice forms. c-FLIP is often overexpressed in various human cancers, including breast cancer. Several studies have shown that silencing c-FLIP by specific siRNAs sensitizes cancer cells to TRAIL and anticancer agents. However, systemic use of siRNA as a therapeutic agent is not practical at present. In order to reduce or inhibit c-FLIP expression, small molecules are needed to allow targeting c-FLIP without inhibiting caspases-8 and -10. We used a small molecule inhibitor of c-FLIP, 4-(4-chloro-2-methylphenoxy)-N-hydroxybutanamide (CMH), and show that CMH, but not its inactive analog, downregulated c-FLIPL and c-FLIPS mRNA and protein levels, caused poly(ADP-ribose) polymerase (PARP) degradation, reduced cell survival, and induced apoptosis in MCF-7 breast cancer cells. These results revealed that c-FLIP is a critical apoptosis regulator that can serve as a target for small molecule inhibitors that downregulate its expression and serve as effective targeted therapeutics against breast cancer cells. 相似文献
995.
Xi-Mei Zhang Qiu-Ming Li Dong-Ju Su Ning Wang Zhi-Yan Shan Lian-Hong Jin Lei Lei 《Molecular biology reports》2010,37(3):1197-1202
Recently, differentiated somatic cells had been reprogrammed to pluripotential state in vitro, and various tissue cells had
been elicited from those cells. Epigenetic modifications allow differentiated cells to perpetuate the molecular memory needed
for the cells to retain their identity. DNA methylation and histone deacetylation are important patterns involved in epigenetic
modification, which take critical roles in regulating DNA expression. In this study, we dedifferentiated NIH/3T3 fibroblasts
by 5-aza-2-deoxycytidine (5-aza-dC) and Trichstatin A (TSA) combination, and detected gene expression pattern, DNA methylation
level, and differentiation potential of reprogrammed cells. As the results, embryonic marker Sox2, klf4, c-Myc and Oct4 were
expressed in reprogrammed NIH/3T3 fibroblasts. Total DNA methylation level was significant decreased after the treatment.
Moreover, exposure of the reprogrammed cells to all trans-retinoic acid (RA) medium elicited the generation of neuronal class
IIIβ-tubulin-positive, neuron-specific enolase (NSE)-positive, nestin-positive, and neurofilament light chain (NF-L)-positive
neural-like cells. 相似文献
996.
Sheng-Yi Lin Chi-Mei Hsueh Sung-Liang Yu Chih-Chung Su Weng-Yoon Shum Kuan-Chuan Yeh Gee-Chen Chang Jeremy J. W. Chen 《Nucleic acids research》2010,38(18):6148-6158
Carcinogenesis is determined based on both cell proliferation and death rates. Recent studies demonstrate that heat shock proteins (HSPs) regulate apoptosis. HLJ1, a member of the DnaJ-like Hsp40 family, is a newly identified tumor suppressor protein closely related to relapse and survival in non-small cell lung cancer (NSCLC) patients. However, its role in apoptosis is currently unknown. In this study, NSCLC cell lines displaying varying HLJ1 expression levels were subjected to ultraviolet (UV) irradiation, followed by flow cytometry. Interestingly, the percentages of apoptotic cells in the seven cell lines examined were positively correlated with HLJ1 expression. Enforcing expression of HLJ1 in low-HLJ1 expressing highly invasive cells promoted UV-induced apoptosis through enhancing JNK and caspase-3 activation in NSCLC. Additionally, UV irradiation led to reduced levels of HLJ1 predominantly in apoptotic cells. The pan-caspase inhibitor, zVAD-fmk and caspase-3-specific inhibitor, DEVD-fmk, prevented UV-induced degradation of HLJ1 by the late stage of apoptosis. Further experiments revealed a non-typical caspase-3 cleavage site (MEID) at amino acid 125–128 of HLJ1. Our results collectively suggest that HLJ1 is a novel substrate of caspase-3 during the UV-induced apoptotic process. 相似文献
997.
Xin Chai Yan-Fang Su Yun-Hui Zheng Shi-Lun Yan Xiao Zhang Xiu-Mei Gao 《Biochemical Systematics and Ecology》2010
A chemical investigation of the roots of Triosteum pinnatifidum led to the isolation of 10 iridoids, elucidated as triohimas A–C, naucledal, secologanin dimethyl acetal, grandifloroside, sweroside, loganin, vogeloside and (E)-aldosecologanin. Most of the compounds were derived from loganin or secologanin with a glucose moiety at C-1 position. The results indicate a close relationship between the two genera Triosteum and Lonicera, and support the viewpoint that the iridoids derived from loganin or secologanin could be the chemotaxonomic markers of the Caprifoliaceae family. 相似文献
998.
Dacrycarpus imbricatus is a vulnerable conifer in China whose geographical distribution encompasses large island but small mainland populations, providing a framework for contrasting the patterns of population genetic composition. In this study, seven populations on Hainan Island and the Chinese mainland were sampled throughout its distribution range and assessed using ISSR. The results did not show significant differences neither in genetic variation nor in genetic differentiation between the island and the mainland populations (P > 0.05). Severe bottlenecks were identified at population, island/mainland as well as range-wide scales. A relatively high level of variation but a low degree of differentiation was revealed. Ecological and life traits were suggested to play main roles in the shaping of genetic variation pattern. Of them long generation times could have exerted a lagging effect on both the genetic variation and differentiation. Our findings may contribute to establish management practices. 相似文献
999.
Huaping Lei Yonggang Wang Fengyin Liang Weiwei Su Yifan Feng Xiaoling Guo Ning Wang 《Biochemical Systematics and Ecology》2010
Essential oils were isolated from the leaves of Platycladus orientalis growing in 16 areas of China. The essential oils were analyzed by gas chromatography and gas chromatography-mass spectrometry. In total, 98 volatile compounds were identified. Chemical variability in essential oil composition was evaluated using cluster analysis and principal component analysis. The two analyses led to the identification of four chemotypes: α-pinene, α-pinene/3-carene, cedrol, and cedrol/terpinyl acetate. Geographically, the populations growing in close proximity had similar essential oil composition. The chemical variability could possibly be attributed to genetic and environmental factors. 相似文献
1000.
Chieh-Sen Chuang Hong-Lin Su Fu-Chou Cheng Shan-hui Hsu Chi-Fen Chuang Chin-San Liu 《Journal of biomedical science》2010,17(1):9
Although gait change is considered a useful indicator of severity in animal models of Parkinson's disease, systematic and
extensive gait analysis in animal models of neurological deficits is not well established. The CatWalk-assisted automated
gait analysis system provides a comprehensive way to assess a number of dynamic and static gait parameters simultaneously.
In this study, we used the Catwalk system to investigate changes in gait parameters in adult rats with unilateral 6-OHDA-induced
lesions and the rescue effect of dopaminergic neuron transplantation on gait function. Four weeks after 6-OHDA injection,
the intensity and maximal area of contact were significantly decreased in the affected paws and the swing speed significantly
decreased in all four paws. The relative distance between the hind paws also increased, suggesting that animals with unilateral
6-OHDA-induced lesions required all four paws to compensate for loss of balance function. At 8 weeks post-transplantation,
engrafted dopaminergic neurons expressed tyrosine hydroxylase. In addition, the intensity, contact area, and swing speed of
the four limbs increased and the distance between the hind paws decreased. Partial recovery of methamphetamine-induced rotational
response was also noted. 相似文献