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排序方式: 共有10000条查询结果,搜索用时 312 毫秒
91.
Sumanta K. Pal MD Dean Bajorin MD Nazli Dizman MD Jean Hoffman-Censits MD David I. Quinn MD Daniel P. Petrylak MD Matthew D. Galsky MD Ulka Vaishampayan MD Ugo De Giorgi MD Sumati Gupta MD Howard A. Burris MD Harris S. Soifer PhD Gary Li PhD Hao Wang PhD Carl L. Dambkowski MD Susan Moran MD Siamak Daneshmand MD Jonathan E. Rosenberg MD 《Cancer》2020,126(11):2597-2606
92.
H N David M Dhilly M Degoulet G Poisnel C Meckler N Vallée J-é Blatteau J-J Risso M Lemaire D Debruyne J H Abraini 《Translational psychiatry》2015,5(7):e594
We investigated the effects of the noble gas argon on the expression of locomotor sensitization to amphetamine and amphetamine-induced changes in dopamine release and mu-opioid neurotransmission in the nucleus accumbens. We found (1) argon blocked the increase in carrier-mediated dopamine release induced by amphetamine in brain slices, but, in contrast, potentiated the decrease in KCl-evoked dopamine release induced by amphetamine, thereby suggesting that argon inhibited the vesicular monoamine transporter-2; (2) argon blocked the expression of locomotor and mu-opioid neurotransmission sensitization induced by repeated amphetamine administration in a short-term model of sensitization in rats; (3) argon decreased the maximal number of binding sites and increased the dissociation constant of mu-receptors in membrane preparations, thereby indicating that argon is a mu-receptor antagonist; (4) argon blocked the expression of locomotor sensitization and context-dependent locomotor activity induced by repeated administration of amphetamine in a long-term model of sensitization. Taken together, these data indicate that argon could be of potential interest for treating drug addiction and dependence. 相似文献
93.
94.
José Roberto Jurado Jorge Hernán Santos Nieto Jairo Ospina Gaitán Constanza Garzón Bonilla Ricardo Villarreal David Acevedo Laura Cabrera Luis Felipe Cabrera Mauricio Pedraza 《Arab Journal Of Gastroenterology》2021,22(2):170-173
Background and study aimsThe COVID-19 outbreak has reorganized surgical team conditions regarding endoscopy. The number of interventions has been reduced, the number of healthcare professionals must be limited, and both the patients and physicians are more protected than ever.Patients and MethodsIn the highest peak of contagion in Colombia, endoscopy, colonoscopy, and esophagogastroduodenoscopy were performed using a low-cost disposable device. A total of 1388 procedures were performed. Every patient was assessed for symptoms via a telephone call, at the health center, and after the procedure, following specific attention routes.ResultsAfter procedure follow-up, no positive cases of COVID-19 were noted.ConclusionThe methodology reduced the risk of infection during the COVID-19 pandemic. 相似文献
95.
Alisson R. Teles Don Daniel Ocay Abdulaziz Bin Shebreen Andrew Tice Neil Saran Jean A. Ouellet Catherine E. Ferland 《The spine journal》2019,19(4):677-686
BACKGROUND CONTEXT
Although 40% of adolescent idiopathic scoliosis (AIS) patients present with chronic back pain, the pathophysiology and underlying pain mechanisms remain poorly understood. We hypothesized that development of chronic pain syndrome in AIS is associated with alterations in pain modulatory mechanisms.PURPOSE
To identify the presence of sensitization in nociceptive pathways and to assess the efficacy of the diffuse noxious inhibitory control in patients with AIS presenting with chronic back pain.STUDY DESIGN
Cross-sectional study.PATIENT SAMPLE
Ninety-four patients diagnosed with AIS and chronic back pain.OUTCOME MEASURES
Quantitative sensory testing (QST) assessed pain modulation and self-reported questionnaires were used to assess pain burden and health-related quality of life.METHODS
Patients underwent a detailed pain assessment using a standard and validated quantitative sensory testing (QST) protocol. The measurements included mechanical detection thresholds (MDT), pain pressure threshold (PPT), heat pain threshold (HPT), heat tolerance threshold (HTT), and a conditioned pain modulation (CPM) paradigm. Altogether, these tests measured changes in regulation of the neurophysiology underlying the nociceptive processes based on the patient's pain perception. Funding was provided by The Louise and Alan Edwards Foundation and The Shriners Hospitals for Children.RESULTS
Efficient pain inhibitory response was observed in 51.1% of patients, while 21.3% and 27.7% had sub-optimal and inefficient CPM, respectively. Temporal summation of pain was observed in 11.7% of patients. Significant correlations were observed between deformity severity and pain pressure thresholds (p=.023) and CPM (p=.017), neuropathic pain scores and pain pressure thresholds (p=.015) and temporal summation of pain (p=.047), and heat temperature threshold and pain intensity (p=.048).CONCLUSIONS
Chronic back pain has an impact in the quality of life of adolescents with idiopathic scoliosis. We demonstrated a high prevalence of impaired pain modulation in this group. The association between deformity severity and somatosensory dysfunction may suggest that spinal deformity can be a trigger for abnormal neuroplastic changes in this population contributing to chronic pain syndrome. 相似文献96.
Jason Saliba Nikki A. Evensen Julia A. Meyer Daniel Newman Jacob Nersting Sonali Narang Xiaotu Ma Kjeld Schmiegelow William L. Carroll 《Pediatric blood & cancer》2020,67(7)
Relapse‐enriched somatic variants drive drug resistance in childhood acute lymphoblastic leukemia. We used digital droplet‐based polymerase chain reaction to establish whether relapse‐enriched mutations in emerging subclones could be detected in peripheral blood samples before frank relapse. Although limitations in sensitivity for some probes hindered detection of certain variants, we successfully detected variants in NT5C2 and PRPS1 at a fractional abundance of 0.005% to 0.3%, 41 to 116 days before relapse. As mutations in both these genes confer resistance to thiopurines, early detection protocols using peripheral blood could be implemented to preemptively alter maintenance therapy to extinguish resistant clones before overt relapse. 相似文献
97.
98.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla. 总被引:2,自引:0,他引:2
Dirk Mayer Dong-Hyun Kim Elfar Adalsteinsson Daniel M Spielman 《Magnetic resonance in medicine》2006,55(5):974-978
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner. 相似文献
99.
Mark W Woolrich Peter Chiarelli Daniel Gallichan Joanna Perthen Thomas T Liu 《Magnetic resonance in medicine》2006,56(4):891-906
The study of brain function using MRI relies on acquisition techniques that are sensitive to different aspects of the hemodynamic response contiguous to areas of neuronal activity. For this purpose different contrasts such as arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional MRI techniques have been developed to investigate cerebral blood flow (CBF) and blood oxygenation, respectively. Analysis of such data typically proceeds by separate, linear modeling of the appropriate CBF or BOLD time courses. In this work an approach is developed that provides simultaneous inference on hemodynamic changes via a nonlinear physiological model of ASL data acquired at multiple echo times. Importantly, this includes a significant contribution by changes in the static magnetization, M, to the ASL signal. Inference is carried out in a Bayesian framework. This is able to extract, from dual-echo ASL data, probabilistic estimates of percentage changes of CBF, R(2) (*), and the static magnetization, M. This approach provides increased sensitivity in inferring CBF changes and reduced contamination in inferring BOLD changes when compared with general linear model approaches on single-echo ASL data. We also consider how the static magnetization, M, might be related to changes in CBV by assuming the same mechanism for water exchange as in vascular space occupancy. 相似文献
100.