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21.
Li Li Alice C Jiang Pin Dong Yi Wan Zi Wei Yu 《Otolaryngology--head and neck surgery》2007,137(4):659-664
OBJECTIVE: To investigate the characteristics of Hep-2 cell with multidrug resistance (MDR) induced by Taxol. STUDY DESIGN: Hep-2 cells were exposed in stepwise escalating concentration of Taxol to develop the resistant cell line-Hep-2T. Cell cycle distribution, apoptosis, and rhodamine accumulation were studied through flow cytometry. The MDR1 and MRP1 genes were detected through real-time quantitative RT-PCR, and the corresponding proteins were detected through Western blotting. RESULTS: The drug resistance of Hep-2T cells to Taxol, doxorubicin, gemcitabine, 5-FU, and cisplatin all increased. The percentage of G0/G1 phase and the antiapoptosis ability increased significantly compared with Hep-2 cells. Both MDR1 and MRP1 also increased at gene and protein level, though MDR1 was more prominent. CONCLUSION: More emphasis should be laid on MDR1/Pgp, the non-Pgp substrate chemotherapeutic agents, and the changes of cell cycle distribution to prevent MDR induced by Taxol. SIGNIFICANCE: These findings may provide theoretical support for the reverse of MDR. 相似文献
22.
Empty Sella and Headache 总被引:2,自引:0,他引:2
Teresa Catarci Fabrizio Fiacco Luigi Bozzao Manuela Pati Alice Valeria Magiar Rosanna Cerbo 《Headache》1994,34(10):583-586
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献
23.
24.
D Michal Freedman Alice Sigurdson Michele Morin Doody Kiyohiko Mabuchi Martha S Linet 《Cancer epidemiology, biomarkers & prevention》2003,12(12):1540-1543
We prospectively investigated whether alcohol intake and smoking affect the risk of basal cell carcinoma (BCC) in subjects from the United States Radiological Technologists (USRT) cohort study. We evaluated 68,371 radiological technologists certified during 1926-1982 who were free of cancer at the time they answered a first questionnaire (1983-1989) and who completed a second questionnaire (1994-1998). The first questionnaire provided baseline information on numerous risk factors, including smoking and alcohol intake, and the second provided self-reported cancer diagnoses. During 698,190 person-years of follow-up, we identified 1,360 cases of BCC: 1,036 in women and 324 in men. Cox proportional hazards regression indicated that the trend in BCC was significantly associated with increased alcohol intake (P for trend = 0.001). Compared with those who reported no alcohol consumption, those who drank <1-2, 3-6, 7-14, and >14 drinks/week had multivariate risks of 1.1 [95% confidence interval (CI), 0.9-1.3], 1.3 (95% CI, 1.1-1.5), 1.4 (95% CI, 1.2-1.7), and 1.0 (95% CI, 0.7-1.6), respectively. We found no clear association between smoking and BCC. This is the second large prospective study to report a significant but nonmonotonic trend in increased risk associated with alcohol consumption. 相似文献
25.
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27.
Alice J Hausman Ph.D. M.P.H. Howard Spivak M.D. Deborah Prothrow-Stith M.D. James Roeber M.S. 《The Journal of adolescent health》1992,13(8):668-675
This paper describes the implementation of a community-based youth violence prevention project that utilized an educational curriculum and a mass media campaign. The extent of penetration of the intervention into target areas and the degree of contamination of control areas are assessed, and the most frequently contacted forms of educational outreach are identified. Two sources of data, provider interviews and a random digit dialed telephone survey, were used to track the source and extent of teens' exposure to the intervention. Agency provider data revealed that 40% of the 92 contacted agencies actually conducted violence prevention education, reaching 22% of the target area teens. Approximately one-half of the surveyed teens reported some exposure to the program, with 13% of the teens in target areas reporting participation in interactive educational activities associated with the project. The most common source of exposure was the media campaign. Most teens report a single exposure, usually to the media campaign, although 29% report contact with more than one form of violence prevention education. While the project did not achieve community saturation, the data show that the community-based model of intervention for violence prevention is feasible and effective in reaching teenagers. This research highlights some difficulties in evaluating prevention programs, including reconciling community ownership with project identification, the ethics of curtailing services for control purposes, and factors influencing recall of participation. 相似文献
28.
Mo Therese Hannah Ellen R. Gritz David K. Wellisch Pat Fobair Richard T. Hoppe Joan R. Bloom Guo-Wen Sun Anna Varghese Malcolm D. Cosgrove David Spiegel 《Psycho-oncology》1992,1(2):89-103
This study compares the effects of the cancer experience on various aspects of marital and sexual functioning (e.g., communication, emotional support, body image, sexual satisfaction and frequency) for two groups of long-term cancer survivors (testicular cancer and Hodgkin's disease) and their spouses. Comparisons between the two patient groups showed significantly more survivors of Hodgkin's disease than testicular cancer reporting the emergence of special issues and changes in the marital relationship. No differences emerged between the spouse groups on sexual functioning variables; however, spouses of survivors of Hodgkin's disease were more likely than spouses of survivors of testicular cancer to report the development of special issues and communication difficulties. A substantial proportion of both survivor groups disclosed negative changes in body image and sexual frequency. Majorities of both survivors and spouses acknowledged that the illness had drawn them closer together. When representative marital/sexual functioning variables were used to predict Family Environment Scale (FES) scores for survivors and for spouses, changes in the spouse's importance, influence of the illness on the relationship, and changes in sexual frequency emerged as significant predictors. The clinical significance of long-term changes in marital and sexual functioning for the couple and the need for therapeutic interventions are discussed. 相似文献
29.
Anne M Lewis Sheelu Varghese Hui Xu H Richard Alexander 《Journal of translational medicine》2006,4(1):48
The tumor microenvironment consists of tumor, immune, stromal, and inflammatory cells which produce cytokines, growth factors,
and adhesion molecules that promote tumor progression and metastasis. Of particular interest in this setting is interleukin-1
(IL-1), a pleiotropic cytokine with numerous roles in both physiological and pathological states. It is known to be up regulated
in many tumor types and has been implicated as a factor in tumor progression via the expression of metastatic and angiogenic
genes and growth factors. A number of studies have reported that high IL-1 concentrations within the tumor microenvironment
are associated with a more virulent tumor phenotype. Solid tumors in which IL-1 has been shown to be up regulated include
breast, colon, lung, head and neck cancers, and melanomas, and patients with IL-1 producing tumors have generally bad prognoses.
The exact mechanisms by which IL-1 promotes tumor growth remain unclear, though the protein is believed to act via induction
of pro-metastatic genes such as matrix metalloproteinases and through the stimulation of adjacent cells to produce angiogenic
proteins and growth factors such as VEGF, IL-8, IL-6, TNFα, and TGFβ. The IL-1 receptor antagonist (IL-1ra) is a naturally
occurring inhibitor to IL-1 and acts by binding to the IL-1 receptor without activating it. The protein has been shown to
decrease tumor growth, angiogenesis, and metastases in murine xenograft models. Our focus in this review is to summarize the
known data on the role of IL-1 in tumor progression and metastasis and the use of IL-1 inhibition as a novel therapeutic approach
in the treatment of solid organ malignancies. 相似文献
30.
Impaired cortisol stress response in fish from environments polluted by PAHs,PCBs, and mercury 总被引:6,自引:0,他引:6
Alice Hontela Joseph B. Rasmussen Céline Audet Gaston Chevalier 《Archives of environmental contamination and toxicology》1992,22(3):278-283
The cortisol stress response to capture was investigated in two species of fish (Perca flavescens and Esox lucius) from sites polluted by high levels of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and mercury, and from reference sites in the St. Lawrence river system. Fish from the reference sites exhibited the normal elevation of serum cortisol in response to the acute stress of capture and had large pituitary corticotropes. In contrast, fish from the most polluted sites were unable to increase their serum cortisol in response to the acute stress of capture and their pituitary corticotropes were atrophied. These results suggest that a life-long exposure to chemical pollutants may lead to an exhaustion of the cortisol-producing endocrine system, possibly as a result of prolonged hyperactivity of the system. 相似文献