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排序方式: 共有1139条查询结果,搜索用时 15 毫秒
991.
Autocrine stimulation of the type I insulin-like growth factor receptor (IGF-IR) by IGF-II is one mechanism that allows cancer cells to maintain unregulated growth and to resist programmed cell death (PCD). SH-SY5Y and SHEP cells are cloned human neuroblastoma (NBL) lines originating from a single primary tumor. SH-SY5Y cells, which express abundant cell surface IGF-IR and produce IGF-II, exhibit serum independent growth and resist PCD due to hypoxia and hyperosmolar conditions. In contrast, SHEP cells, which produce no IGF-II and express five-fold fewer IGF-IRs, die in serum-free media or following exposure to metabolic stressors. To better understand the roles of IGF-IR and its ligand, IGF-II, in NBL carcinogenesis, we stably transfected SHEP cells with either IGF-II or IGF-IR. Unregulated expression of IGF-II did not alter the growth characteristics of SHEP/human IGF-II transfectants. In contrast, overexpression of IGF-IR allowed SHEP/IGF-IR transfectants to survive in media supplemented only by IGF-II. IGF-IR abundance correlated in a graded fashion with resistance to PCD in response to three different death-inducing paradigms: mitogen withdrawal, hyperosmolar metabolic stress, and treatment with etoposide. Our results suggest that adjuvant therapy aimed at reducing IGF-IR abundance may enhance chemotherapy-coupled apoptosis in the treatment of NBL. 相似文献
992.
K Hawton E Arensman E Townsend S Bremner E Feldman R Goldney D Gunnell P Hazell K van Heeringen A House D Owens I Sakinofsky L Tr?skman-Bendz 《Canadian Metallurgical Quarterly》1998,317(7156):441-447
OBJECTIVE: To identify and synthesise the findings from all randomised controlled trials that have examined the effectiveness of treatments of patients who have deliberately harmed themselves. DESIGN: Systematic review of randomised controlled trials of psychosocial and physical treatments. Studies categorised according to type of treatment. When there was more than one investigation in a particular category a summary odds ratio was estimated with the Mantel-Haenszel method. SETTING: Randomised trials available in electronic databases in 1996, in the Cochrane Controlled Trials Register in 1997, and from hand searching of journals to 1997. SUBJECTS: Patients who had deliberately harmed themselves shortly before entry into the trials with information on repetition of behaviour. The included trials comprised 2452 randomised participants with outcome data. MAIN OUTCOME MEASURE: Repetition of self harm. RESULTS: 20 trials reported repetition of self harm as an outcome variable, classified into 10 categories. Summary odds ratio (all for comparison with standard aftercare) indicated reduced repetition for problem solving therapy (0.73; 95% confidence interval 0.45 to 1.18) and for provision of an emergency contact card in addition to standard care (0.45; 0.19 to 1.07). The summary odds ratios were 0.83 (0.61 to 1.14) for trials of intensive aftercare plus outreach and 1.19 (0.53 to 2.67) for antidepressant treatment compared with placebo. Significantly reduced rates of further self harm were observed for depot flupenthixol versus placebo in multiple repeaters (0.09; 0.02 to 0.50) and for dialectical behaviour therapy versus standard aftercare (0.24; 0.06 to 0.93). CONCLUSION: There remains considerable uncertainty about which forms of psychosocial and physical treatments of patients who harm themselves are most effective. Further larger trials of treatments are needed. 相似文献
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To compare children's socialized behavior to parents and non-parental agents, this study examined self-regulated compliance to mothers and caregivers--an early form of internalization--in 90 toddlers, half of whom were also observed with fathers. Adults were observed in play, teaching, and discipline sessions with the child and were interviewed on child-rearing philosophies. Child cognition and emotion regulation were assessed, and naturalistic observations were conducted at child-care locations. Mean-level and rank-order stability were found in child compliance to the 3 adults. Child emotion regulation and adult warm control in a discipline situation were related to self-regulated compliance to the mother, caregiver, and father. Compliance to parents correlated with parental sensitivity and philosophies, and compliance to the caregiver correlated with child cognition and social involvement when child-care quality was controlled. Maternal sensitivity and warm control discipline predicted compliance to the caregiver but not vice versa. Results are consistent with theoretical positions on the generalization of socialization from the mother to non-maternal agents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The design and use of fixed partial dentures as a definitive restoration to stabilize and splint teeth have been reviewed. The provisionalization of the splinted patient has been described as it is incorporated into the treatment plan of patients with a weakened periodontium. The current controversy of incorporating implants in the patient requiring splinting was discussed, and recommendations are made. Dentists are encouraged to explain all potential ramifications of splinting with fixed partial dentures, including cost, frequency of office visits, and potential alterations or remakes of the prosthesis should physiologic demands surpass the capabilities of the remaining teeth. 相似文献
998.
Kirill N. Ilinski Alexander Moroz 《Journal of research of the National Institute of Standards and Technology》1996,101(4):567-573
Characteristics of the initial condensate in the recent experiment on Bose-Einstein condensation (BEC) of 87Rb atoms in an anisotropic magnetic trap are discussed. Given the aspect ratio R, the quality of BEC is estimated. A simple analytical ansatz for the initial condensate wave function is proposed as a function of the aspect ratio which, in contrast to the Baym-Pethick trial wave function, can be used for any interaction strength, reproduces both the weak and the strong interaction limits, and which is in better agreement with numerical results than the latter. 相似文献
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