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11.
姜黄素诱导人肺癌细胞凋亡的作用机制初步研究 总被引:13,自引:3,他引:13
目的 探讨姜黄素对人肺腺癌细胞 (SPC A1 )抗癌作用机制。方法 采用细胞培养、荧光显微镜、原位末端标记、放射免疫、原位杂交等技术 ,探讨姜黄素抗癌作用及其机制。结果 ①姜黄素作用于癌细胞后 ,光镜下可见有细胞脱壁 ,悬浮培养液中 ;荧光镜下可见细胞核破碎 ,裂解成大小不等的凋亡小体 ,原位末端标记法进一步证实 2 0 μmol·L- 1 姜黄素作用 2 4h凋亡率达 42 67%。②姜黄素作用于癌细胞后 ,使细胞内cAMP浓度升高。③ 2 0 μmol·L- 1 姜黄素作用于癌细胞 2 4h后 ,使人肺癌细胞半胱氨酸蛋白酶 8(Caspase 8)mRNA表达明显增高。结论 姜黄素可诱导人肺癌细胞凋亡 ,其作用机制可能与细胞内cAMP浓度升高、Caspase 8表达增高有关 相似文献
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目的:探索上海地区农民人群中α-雌激素受体基因(ER-α)及芳香烃受体基因(Ahr)不同基因形态和老年痴呆症高发风险的可能联系.方法:分别以PCR—RFLP和AS—PCR方法分析一组老年痴呆症患者(n=52)ER-α基因及Ahr基因的多态位点,同一地区的健康人群(n=125)为对照.结果:Alzheimer症病人ER-α基因两个位点突变形态频率显著高于对照人群(Pvu Ⅱ位点:P=0.023,OR=2.94,95%CI 1.13—7.71;Xba I位点:P=0.046,0R=2.28,95% CI 1.003—5.17).Ahr G1721A位点基因型频率在病人组和对照组间无显著差异.结论:ER-α基因多态性可能与Alzheimer症易感性个体差异有关,本工作不支持Ahr基因多态性与老年痴呆症高发风险间的可能关联. 相似文献
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Jann‐Inn Tzeng Ting‐Yun Chen Jhi‐Joung Wang Ching‐Hsia Hung 《Fundamental & clinical pharmacology》2014,28(4):439-444
Although diphenhydramine has been shown to produce longer duration of spinal block than lidocaine, few studies disclose its skin infiltrative anesthesia when compared with a long‐lasting local anesthetic, bupivacaine. The purpose of this study was to investigate whether diphenhydramine elicited cutaneous analgesia in comparison with bupivacaine. After inhibition of cutaneous trunci muscle reflex via subcutaneous injection of drugs in rats, we examined the local anesthetic effect of diphenhydramine and bupivacaine as infiltrative cutaneous analgesia in a dose‐dependent fashion. We showed that diphenhydramine, as well as bupivacaine displayed a dose‐dependent cutaneous analgesia in response to dorsal cutaneous noxious stimuli. The relative potency (50% effective dose) was bupivacaine (0.023 [0.013–0.035]%) > diphenhydramine (0.078 [0.068–0.091]%; P < 0.001). On an equipotent basis, diphenhydramine had a similar duration of action to bupivacaine. Neither local injection of saline nor intraperitoneal administration of a large dose of diphenhydramine or bupivacaine produced cutaneous analgesia (data not shown). We conclude that diphenhydramine is less potent than bupivacaine at producing cutaneous analgesia. At equipotent doses for infiltrative cutaneous analgesia, the duration of action of diphenhydramine is equal to that of bupivacaine. 相似文献
14.
Chia-Ying Lee Huei-ling Yen Pei-wen Yeh Wan-Hsuan Lin Ying-Ying Cheng Yu-Lin Tzeng Hsin-Chi Wu 《Neuropsychologia》2012,50(14):3228-3239
The present study investigates how age, phonological saliency, and deviance size affect the presence of mismatch negativity (MMN) and positive mismatch response (P-MMR). This work measured the auditory mismatch responses to Mandarin lexical tones, initial consonants, and vowels in 4- to 6-year-old preschoolers using the multiple-deviant oddball paradigm. The data showed the coexistence of MMN and P-MMR in the same age group when responding to the three types of syllabic features in Mandarin. The transition from a predominantly positive response to a predominantly negative response supported the multiple MMN mechanisms. Congruent with the phonological saliency hypothesis and the phonetic acquisition order of Mandarin in behavioral studies, for the compulsory elements of Mandarin syllables, lexical tones, and vowels, the larger deviants elicited adult-like MMNs, whereas the smaller deviants elicited P-MMRs. The optional elements of the Mandarin syllables, the initial consonant, only elicited P-MMR in preschoolers. These findings suggest that MMN and P-MMR index different functional characteristics and may provide information on when and how children's speech perception becomes automatic at different developmental stages. 相似文献
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Wen-Sheng Tzeng Reng-Hong Wu Steven Kuan-Hua Huang Chee-Wai Mak Alex Chien-Hwa Liao Victor Chia-Hsiang Lin 《Clinical imaging》2012,36(6):773-779
Radiologists and urologists require practical and helpful image reconstructions for diagnosing urinary obstruction. We performed different types of imaging and reconstruction, then used a self-designed urinary obstruction-specific questionnaire to evaluate the diagnostic outcome of them. Our results suggested that two-dimensional (2D) axial computed tomography (CT) is clinically superior to retrograde pyelography or antegrade pyelography, and to other modes of image reconstruction that are often used for diagnosing urinary obstruction. 相似文献
17.
Chuan-Chia Chang Yu-Chen Kao Che-Yi Chao Nian-Sheng Tzeng Hsin-An Chang 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2021,24(1):40
BackgroundWe previously showed the efficacy of bi-anodal transcranial direct current stimulation (tDCS) over the prefrontal cortex (PFC) regions with extracephalic reference placement in improving negative symptoms in schizophrenia. In this ancillary investigation, the effects of this intervention on insight levels, other clinical outcomes, and cardio-respiratory and autonomic functions were examined and the potential of biomarkers for treatment response was explored.MethodsSchizophrenia patients were randomly allocated to receive 10 sessions of bi-anodal tDCS over the PFC regions with extracephalic reference placement (2 mA, 20 minutes, twice daily for 5 weeks) or sham stimulation. We examined, in 60 patients at baseline, immediately after stimulation and at follow-up visits, the insight levels, other clinical outcomes, blood pressure, respiratory rate, heart rate, and heart rate variability.ResultsInsight levels as assessed by the abbreviated version of the Scale to Assess Unawareness in Mental Disorder in schizophrenia awareness of the disease, positive and negative symptoms dimensions, and beliefs about medication compliance as assessed by Medication Adherence Rating Scale were significantly enhanced by active stimulation relative to sham. No effects were observed on cognitive insight, other clinical outcomes, or cardio-respiratory and autonomic functions. Heart rate variability indices as biomarkers were not associated with the clinical response to the intervention.ConclusionsOur results provide evidence for bi-anodal tDCS over the PFC regions with extracephalic reference placement in heightening the levels of insight into the disease and symptoms, as well as beliefs about medication compliance in schizophrenia, without impacting other clinical outcomes and cardio-respiratory/autonomic functions. 相似文献
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19.
Influence of cyclic loading on the fracture toughness and load bearing capacities of all-ceramic crowns 总被引:1,自引:0,他引:1
Rao-Rao Wang Cheng-Lin Lu Gang Wang Dong-Sheng Zhang 《International journal of oral science》2014,6(2):99-104
The purpose of this study was to investigate how cyclic loading influenced the fracture toughness of hot-press lithium disilicate and zirconia core materials and whether there was an increase in the propensity for crown failure. Two types of all-ceramic crowns including the IPS e.max Press system (n=24) and the Lava zirconia system (n=24), were selected. Sectioned specimens were subjected to cyclic loading with the maximum magnitude of 200 N (R=0.1) until two million cycles. The material properties including Young's modulus (E) and hardness (H) and the fracture toughness (K,c) of the core materials were evaluated using indentation methods (n= 12 each). The load-bearing capacities of the specimens were examined by means of monotonic load to fracture (n=12 each). It was found that the material properties, including E, Hand Knc, of the two types of dental ceramics, were reduced. Statistical analysis indicated that there were no significant influences of fatigue loading on material properties E and H for both types of dental ceramics or Kgc for zirconia, while for the IPS e.max Press core, K,c, which was parallel to the direction of the lithium disilicate crystals, was significantly reduced (P-0.001). A conclusion was drawn that zirconia possesses high mechanical reliability and sustainable capacity to resist fatigue loading, while fatigue loading remarkably degraded the anisotropic mechanical behaviour of hot-press lithium disilicate ceramics. 相似文献
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