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排序方式: 共有5583条查询结果,搜索用时 93 毫秒
971.
972.
JA GallegosVargasJ SanchezRoldanMD RonquilloSanchezL Carmona AparicioE FlorianoSanchezN CardenasRodriguez 《Asian Pacific journal of cancer prevention》2016,17(7):3477-3482
Background: Thyroid cancer is the most common endocrine malignancy, and exact causes remain unknown. The role of CYP450 1A1 (CYP1A1) in cancer initiation and progression has been investigated. The aim of this work was to analyze, for the first time, CYP1A1 gene expression and its relationship with several clinicopathological factors in Mexican patients diagnosed with thyroid cancer. Materials and Methods: Realtime PCR analysis was conducted on 32 sets of thyroid tumors and benign pathologies. Expression levels were tested for correlations with clinical and pathological data. All statistical analysis were performed using GraphPad Prism version 3.0 software. Results: We found that female gender was associated with thyroid cancer risk (P<0.05). A positive relationship was identified between CYP1A1 mRNA levels and the presence of chronic disease, alcohol use, tumor size, metastasis and an advanced clinical stage (P<0.05). Conclusions: The results suggest that CYP1A1 gene expression could be used as a marker for thyroid cancer. 相似文献
973.
Nooman Gilani Sally Stipho James D Panetta Sorin Petre Michele A Young Francisco C Ramirez 《World journal of gastrointestinal endoscopy》2015,7(5):555-562
AIM: To compare the yield of adenomas between narrow band imaging and white light when using high definition/magnification. METHODS: This prospective, non-randomized comparative study was performed at the endoscopy unit of veteran affairs medical center in Phoenix, Arizona. Consecutive patients undergoing first average risk colorectal cancer screening colonoscopy were selected. Two experienced gastroenterologists performed all the procedures that were blinded to each other's findings. Demographic details were recorded. Data are presented as mean ± SEM. Proportional data were compared using the χ2 test and means were compared using the Student's t test. Tandem colonoscopy was performed in a sequential and segmental fashion using one of 3 strategies: white light followed by narrow band imaging [Group A: white light(WL) → narrow band imaging(NBI)]; narrow band imaging followed by white light(Group B: NBI → WL) and, white light followed by white light(Group C: WL → WL). Detection rate of missed polyps and adenomas were evaluated in all three groups. RESULTS: Three hundred patients were studied(100 in each Group). Although the total time for the colonoscopy was similar in the 3 groups(23.8 ± 0.7, 22.2 ± 0.5 and 24.1 ± 0.7 min for Groups A, B and C, respectively), it reached statistical significance between Groups B and C(P 0.05). The cecal intubation time in Groups B and C was longer than for Group A(6.5 ± 0.4 min and 6.5 ± 0.4 min vs 4.9 ± 0.3 min; P 0.05). The withdrawal time for Groups A and C was longer than Group B(18.9 ± 0.7 min and 17.6 ± 0.6min vs 15.7 ± 0.4 min; P 0.05). Overall miss rate for polyps and adenomas detected in three groups during the second look was 18% and 17%, respectively(P = NS). Detection rate for polyps and adenomas after first look with white light was similar irrespective of the light used during the second look(WL → WL: 13.7% for polyps, 12.6% for adenomas; WL → NBI: 14.2% for polyps, 11.3% for adenomas). Miss rate of polyps and adenomas however was significantly higher when NBI was used first(29.3% and 30.3%, respectively; P 0.05). Most missed adenomas were ≤ 5 mm in size. There was only one advanced neoplasia(defined by size only) missed during the first look. CONCLUSION: Our data suggest that the tandem nature of the procedure rather than the optical techniques was associated with the detection of additional polyps' and adenomas. 相似文献
974.
Since the discovery of therapeutic insulin in 1922 and the development of the non-obese diabetic spontaneous mouse model in 1980, the establishment of Network for the Pancreatic Organ Donor with Diabetes (nPOD) in 2007 is arguably the most important milestone step in advancing type 1 diabetes (T1D) research. In this perspective, we briefly describe how nPOD is transforming T1D research via procuring and coordinating analysis of disease pathogenesis directly in human organs donated by deceased diabetic and control subjects. The successful precedent set up by nPOD is likely to spread far beyond the confines of research in T1D to revolutionize biomedical research of other disease using high quality procured human cells and tissues. 相似文献
975.
Berrade L Aisa B Ramirez MJ Galiano S Guccione S Moltzau LR Levy FO Nicoletti F Battaglia G Molinaro G Aldana I Monge A Perez-Silanes S 《Journal of medicinal chemistry》2011,54(8):3086-3090
We report benzo[b]thiophene derivatives synthesized according to a dual strategy. 8j, 9c, and 9e with affinity values toward 5-HT(7)R and 5-HTT were selected to probe their antidepressant activity in vivo using the forced swimming text (FST). The results showed significant antidepressant activity after chronic treatment. 9c was effective in reducing the immobility time in FST even after acute treatment. These findings identify these compounds as a new class of antidepressants with a rapid onset of action. 相似文献
976.
977.
Forbes LJ Atkins L Thurnham A Layburn J Haste F Ramirez AJ 《British journal of cancer》2011,105(10):1474-1479
Background:
During 2001 to 2005, 1-year breast cancer survival was low in ethnically diverse East London. We hypothesised that this was due to low breast cancer awareness and barriers to symptomatic presentation, leading to late stage at diagnosis in women from ethnic minorities. We examined ethnic differences in breast cancer awareness and barriers to symptomatic presentation in East London.Methods:
We carried out a population-based survey of 1515 women aged 30+ using the Cancer Research UK Breast Cancer Awareness Measure. We analysed the data using logistic regression adjusting for age group and level of deprivation.Results:
South Asian and black women had lower breast cancer awareness than white women. South Asian women, but not black women, reported more emotional barriers to seeking medical help than white women. White women were more likely than non-white women to report worry about wasting the doctor''s time as a barrier to symptomatic presentation.Conclusion:
Interventions to promote early presentation of breast cancer for South Asian and black women should promote knowledge of symptoms and skills to detect changes, and tackle emotional barriers to symptomatic presentation and for white women tackle the idea that going to the doctor to discuss a breast symptom will waste the doctor''s time. 相似文献978.
979.
Statins have recently been shown to act as protectants against several neuropathological conditions. They have received special attention in the field of Alzheimer's disease (AD), where epidemiological studies indicating a lower prevalence of AD/dementia in statin-prescribed populations. Excitotoxicity, which derives from the overstimulation of glutamate receptors, is a major cause of neuron death in several neurological diseases, including AD and epilepsy. We have carried out a comparative study to investigate the effects of all the commercially available statins (simvastatin, lovastatin, fluvastatin, pravastatin, and atorvastatin) on neuron damage and memory impairment. To this end, we studied neurodegeneration in a mouse model by systemic administration of kainate. Simvastatin was the most effective statin in reducing the deleterious effects caused by kainate, including the severity of seizures, excitotoxicity, oxidative damage, neuritic dystrophy and apoptosis in the hippocampus and other limbic structures of the brain cortex. Lovastatin was the second most efficient statin in preventing seizures and histopathological signs of excitotoxicity, whilst fluvastatin, pravastatin, and atorvastatin showed neither antiepileptic nor neuroprotective effects. Only simvastatin enhanced episodic-like memory. To the best of our knowledge this is the first in vivo study to analyze the neuroprotective effect of all the commercially available statins. Our results suggest that both simvastatin and lovastatin (but especially simvastatin) may well have therapeutic potential in the treatment of neurodegenerative diseases involving excitotoxicity and memory impairment, including AD. 相似文献
980.
Ramirez RJ Ajijola OA Zhou W Holmström B Lüning H Laks MM Shivkumar K Mahajan A 《Journal of electrocardiology》2011,(6):694-699
Activation of cardiac sympathetic nerves alters ventricular repolarization; however, these changes remain poorly characterized. The goal of this study was to examine effects of sympathetic stimulation on repolarization to identify electrocardiographic markers of sympathetic activation. Pigs underwent median sternotomy and bilateral thoracotomy to expose the stellate ganglia. Changes in T-wave duration, amplitude, repolarization vector, and time from peak to end (Tp-Te) were continuously monitored. Within 15 seconds of unilateral left or right stellate ganglion (LSG/RSG) stimulation, T-wave amplitude increased 6- and 4.5-fold, respectively, in lead aVF. T-wave duration and Tp-Te both increased 200% during LSG stimulation but only 50% and 30%, respectively, with RSG stimulation. During LSG stimulation, frontal and horizontal T-wave vectors, respectively, changed from 1.9° ± 22.8° and 333.8° ± 9.7° at baseline to 83.4° ± 3.9° (inferiorly) and 306.7° ± 1.8° (posteriorly). During RSG stimulation, frontal and horizontal T-wave vectors changed from 348.2° ± 21.6° and 333.8° ± 10.3° before stimulation to 280.7° ± 4.6° (superiorly) and 118.1° ± 5.6° (anteriorly). During stellate stimulation, T-wave vectors are displaced to angles specific for LSG activation (posteroinferiorly) or RSG activation (anterosuperiorly); T-wave amplitude, duration, and Tp-Te increase; and ST-duration decreases. Displaced repolarization vector and changes in T-wave morphometrics provide a novel marker of unilateral sympathetic nerve stimulation. 相似文献