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排序方式: 共有1200条查询结果,搜索用时 15 毫秒
1.
Marco Bocchetti Maria Grazia Ferraro Filippo Ricciardiello Alessandro Ottaiano Amalia Luce Alessia Maria Cossu Marianna Scrima Wing-Yan Leung Marianna Abate Paola Stiuso Michele Caraglia Silvia Zappavigna Tung On Yau 《International journal of molecular sciences》2021,22(8)
Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment. 相似文献
2.
Landsiedel Justus Root Waleri Schramm Christian Menzel Alexander Witzleben Steffen Bechtold Thomas Pham Tung 《Nano Research》2020,13(10):2658-2664
Nano Research - Development of colored surfaces by formation of nano-structured aggregates is a widely used strategy in nature to color lightweight structures (e.g. butterflies) without the use of... 相似文献
3.
Ajit Sharma Doan Van Thuan Thanh-Dong Pham Mai Hung Thanh Tung Nguyen Thi Thanh Truc Dai-Viet N. Vo 《化学工程与技术》2020,43(4):752-761
FeO-doped TiO2 nanoparticle photocatalysts were immobilized onto the surface of fibrous activated carbon (ACF) via a sol-gel process. As an adsorbent and photocatalyst, FeO-TiO2 on immobilized ACFs (FeO-TiO2/ACF) greatly improved the photocatalysis rate of hydrogen production as compared with pure TiO2 and ACF-TiO2 under UV irradiation and visible light. The addition of ACFs surface significantly reduced the photogenerated pairs of electrons-hole recombination, thereby promoting the photocatalysis action of doped photo-metal oxides of FeO-TiO2. Co-doping of FeO onto the lattice of the TiO2 approach can improve the absorption activity of visible light through photo-metal oxide of TiO2 and further enhance hydrogen production under visible light. The photocatalytic fabrics (FeO-TiO2/ACF) were effortlessly split out from the experimental solution for re-utilization and exhibited high stability even after five complete regeneration cycles. 相似文献
4.
J.A. Bakken L. Barone D. Braun M. Caillat C. Dionisi C. Dor H. Elmamouni F. Ferroni G.L. Grazer J.T. He R. Herbiet B. Ille P. Lecomte E. Longo P.F. Loverre Y.S. Lu J.P. Martin U. Micke R.P. Mount P.A. Pirou H.-G. Sander D. Schmitz M. Schneegans D.P. Stickland R.L. Sumner K.L. Tung E. Valente M. Vivargent 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,228(2-3):294-302
A calorimeter of 25 bismuth germanate (BGO) crystals equipped with silicon photodiode readout has been tested at the CERN SPS in the energy range 1–50 GeV. The response for electrons has been shown to be linear in this energy range and the rms resolution obtained (
) is approximately 1%, for E > 4 GeV. The electron/pion separation was found to be better than 1:500 in the energy range 1–20 GeV. Data on lateral and longitudinal shower development were compared with the results of a Monte Carlo simulation using the SLAC-EGS program and found to be in good agreement. 相似文献
5.
OBJECTIVE: The aim of this study was to evaluate both the importance of the screening strategy and the familial aggregation characteristics of families with hypercholesterolemic children. PATIENTS AND METHODS: Ninety-one families (369 subjects) with one hypercholesterolemic child were studied. In addition to clinical and general biochemical evaluation, lipids including apo A-I and B-100 were examined. LDL was quantified under ultracentrifugation. RESULTS: Among the 91 children studied, 10 (10.99%) suffered heterozygous hypercholesterolemia, while 81 (89.01%) suffered polygenic hypercholesterolemia. Following a diet, polygenic children exhibited normal lipid parameters. In heterozygous children a decrease of 19% for total cholesterol, 19.9% for LDL-cholesterol and 16.3% for apo B were observed. When starting the study, 77.5% of the family members thought that they had normal serum lipid values. At the end of the study it was confirmed that only 28% were really normolipemic, indicating that 49.4% of the individual did not know that they were suffering dyslipemia. The study also showed that fathers exhibited the highest incidence of hypercholesterolemia (80.2%) followed by brothers (65.6%) and mothers (61.5%). Therefore, 69.4% of the individuals studied exhibited dyslipemia. CONCLUSIONS: The screening strategy allows one to diagnose a high percentage (almost 50%) of individuals suffering hypercholesterolemia in families with a child previously diagnosed of this pathology. Moreover, in these families there is a high degree of familiar aggregation of dyslipemia. 相似文献
6.
IC Lavery F Lopez-Kostner VW Fazio M Fernandez-Martin JW Milsom JM Church 《Canadian Metallurgical Quarterly》1997,122(4):779-84; discussion 784-5
BACKGROUND: The goal of this study was to compare patterns of recurrence and long-term outcome after sphincter-saving procedures (SSPs) and abdominoperineal resection (APR) in patients with tumors located in the lower third of the rectum. METHODS: We reviewed the charts of 1001 patients operated on for primary rectal adenocarcinoma between 1980 and 1991. All patients with tumors located between 5 and 7 cm from the anal verge and treated with curative intent were included. RESULTS: Of the 261 patients who met our criteria, 162 had undergone SSP and 99 had undergone APR. The local recurrence rates for SSP and APR were 8% and 11%, respectively (p = 0.41), and the distant metastases rates were 23% and 28%, respectively (p = 0.35). Recurrence and distant metastases rates for SSP and APR, respectively, did not differ by TNM classification: state I, 10% versus 9% (p = 0.9); stage II, 25% versus 43% (p = 0.13); and stage III, 56% versus 57% (p = 0.92). Five-year disease-free survival rates for SSP and APR patients were 70.5% and 62.3%, respectively (p = 0.2). CONCLUSIONS: Tumors in the lower third of the rectum can be treated with sphincter-saving procedures without compromising the chance of cure. 相似文献
7.
8.
PURPOSE: The etiology of voiding dysfunction was determined in men after a cerebrovascular accident who were at risk for obstructive uropathy to evaluate whether the cause of voiding dysfunction could be predicted by the type (obstructive or irritative) or onset of symptoms. MATERIALS AND METHODS: We evaluated 38 men with complaints of voiding dysfunction following a cerebrovascular accident. All patients were of the age when bladder outlet obstruction secondary to benign prostatic hyperplasia would otherwise be prevalent. After a comprehensive history and physical examination, all patients underwent multichannel urodynamic studies at a medium fill rate (20 to 50 ml. per minute). Findings were classified by the Abrams-Griffiths nomogram as obstruction, no obstruction or equivocal. RESULTS: Mean patient age was 70 years (range 54 to 87). Patients were grouped according to the presenting voiding complaints (purely irritative in 42%, purely obstructive in 34% or mixed in 24%). In 34 patients (89%) the onset of symptoms paralleled the occurrence of the cerebrovascular accident. Detrusor hyperreflexia was noted in 82% of the patients. There was no statistically significant difference in the occurrence of detrusor hyperreflexia among the 3 symptom groups (Fisher's exact test). Pressure-flow analysis clearly showed obstruction in 24 patients (63%), no obstruction in 9 (24%) and equivocal results in 5 (13%) according to the nomogram. There was no statistically significant difference in the incidence of obstruction among the 3 symptom groups (Fisher's exact test). CONCLUSIONS: Presenting symptoms did not predict the urodynamic findings of bladder outlet obstruction or detrusor hyperreflexia. The significant incidence of onset of symptoms after stroke suggests that the cerebrovascular accident induced voiding dysfunction in the face of preexisting bladder outlet obstruction may exacerbate the symptoms of the latter condition or vice versa. 相似文献
9.
The AlCoCrCuFeNi high-entropy alloy system was synthesized using a well-developed arc melting and casting method. Their elemental effect on microstructures and hardness was investigated with X-ray diffraction, scanning electron microscopy and Vickers hardness testing. The alloys exhibit quite simple FCC and BCC solid solution phases. Co, Cu and Ni elements enhance the formation of the FCC phase while Al and Cr enhance that of the BCC phase in the alloy system. BCC phases form a spinodal structure during cooling. Copper tends to segregate at the interdendrite region and forms a Cu-rich FCC phase. Low copper content renders the interdendrite as a thin film and the as-cast structure like recrystallized grain structure. The formation of BCC phases significantly increases the hardness level of the alloy system. The strengthening mechanism is discussed. 相似文献
10.
Recent advances in the pharmacology of sedative drugs have expanded their use in the intensive care unit. Indications and endpoints for sedation, however, often are defined poorly and are difficult to assess. Nevertheless, the complications of sedative drug administration are real. New indications for sedation have been proposed in recent years, including enforcing sleep/wake cycles, manipulating cellular metabolism, and preventing myocardial ischemia. The evidence supporting the efficacy of these new indications is not yet complete. 相似文献