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991.
Xinhua Liao Xiangming Che Wei Zhao Danjie Zhang Houlong Long Prakash Chaudhary Haijun Li 《Radiation oncology (London, England)》2010,5(1):1-8
The microRNA-17-92 (miRNA-17-92) cluster, at chromosome 13q31-q32, also known as oncomir-1, consists of seven miRNAs that are transcribed as a polycistronic unit. Over-expression of miRNA-17-92 has been observed in lymphomas and other solid tumors. Whether miRNA-17-92 expression affects the response of tumor cells to radiotherapy is not addressed so far. In the present study, we studied the effects of miRNA-17-92 on the radiosensitivity of human mantle cell lymphoma (MCL) cells Z138c. Over-expression of miRNA-17-92 significantly increased survival cell number, cell proliferation and decreased cell death of human MCL cells after different doses of radiation. Immunoblot analysis showed that phosphatase and tension homolog (PTEN) and PHLPP2 was down-modulated and pAkt activity was enhanced in MCL cells after over-expressing miRNA-17-92 after irradiation. These findings are the first direct evidence that over-expression of miRNA-17-92 cluster significantly increases the radioresistance of human MCL cells, which offers a novel target molecule for improving the radiotherapy of MCL in clinic. 相似文献
992.
Polydiacetylene Nanotubes in Heterogeneous Catalysis: Application to the Gold‐Mediated Oxidation of Silanes 下载免费PDF全文
Elise Villemin Edmond Gravel Dhanaji V. Jawale Praveen Prakash Irishi N. N. Namboothiri Eric Doris 《Macromolecular chemistry and physics.》2015,216(24):2398-2403
A layer‐by‐layer approach is used to anchor small gold nanoparticles onto organic nanotubes resulting from the self‐assembly and polymerization of diacetylene‐containing nitrilotriacetic amphiphiles. The obtained nanotube–gold hybrid is used as a catalyst for the aerobic oxidation of various silanes. With minimal gold loading (0.05 mol%), all substrates are converted into the corresponding silanols with hydrogen gas as the only by‐product. The catalyst operates under mild conditions and can be easily recycled, losing neither activity nor selectivity.
993.
994.
Association of TCF7L2 Polymorphism with Diabetic Nephropathy in the South Indian Population 下载免费PDF全文
995.
Breeze AC Dey PK Lees CC Hackett GA Smith GC Murdoch EM 《Journal of perinatal medicine》2005,33(3):236-240
AIMS AND METHODS: To determine obstetrical and neonatal outcomes in referrals of apparently isolated mild ventriculomegaly following routine ultrasound scan, over the period 2001-2003. Specialist ultrasound and other investigations were performed. Neonatal examination and postnatal ultrasound findings were collected and local neurodevelopmental follow-up was obtained. RESULTS: 30 cases of suspected isolated mild ventriculomegaly (posterior horn of lateral ventricle 10-15 mm at diagnosis) were identified. There were two abnormal karyotypes, no abnormal TORCH screens, and only one false-positive alloimmune thrombocytopenia screen. In 21 cases, isolated ventriculomegaly was confirmed following specialist investigation. In 11 of 21 cases, ventriculomegaly resolved during antenatal follow-up, and in one case it progressed. Six of 21 had ventriculomegaly confirmed on postnatal ultrasound and lissencephaly was diagnosed in one following postnatal MRI. Of the 11 infants with antenatal resolution of ventriculomegaly, 2 have delayed development. The infant with progressive ventriculomegaly has severe developmental problems. 相似文献
996.
Iniyan Appadurai Muthamil Kannan Rajaretinam Rajesh Vincent Samuel Gnana Prakash 《Proceedings of the National Academy of Sciences, India. Section B.》2017,87(1):233-242
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The global-scale failure of bacterial drug resistance calls for an urgent need to develop novel antibiotics.... 相似文献
997.
Bio-based drug carriers have gained significant importance in Control Drug Delivery Systems (CDDS). In the present work, a new iron-based magnetic nano bio-composite (nano-Fe-CNB) is developed in a one-step dry calcination process (solventless) using a seaweed-based biopolymer. The detailed analysis of the developed nano Fe-CNB is carried out using FE-SEM, HR-TEM, P-XRD, XPS, Raman spectroscopy, FTIR etc. and shows that nano-Fe-CNB consists of nanoparticles of 5–10 nm decorated on 7–8 nm thick 2-D graphitic carbon material. The impregnation of nano-Fe-CNB into the calcium alginate (CA) hydrogel beads is found to have good drug loading capacity as well as pH responsive control release behavior which is demonstrated using doxorubicin (DOX) as a model cancer drug. The drug loading experiments exhibit ∼94% loading of DOX and release shows ∼38% and ∼8% release of DOX at pH 5.4 and 7.4 respectively. The developed nano Fe-CNB facilitates strong electrostatic interactions with cationic DOX molecules at pH 7.4 and thereby restricts the release of the drug at physiological pH. However, at cancer cell pH (5.4), the interaction between the drug and nano-Fe-CNB reduces which facilitates more drug release at pH 5.4. Thus, the developed nano-biocomposite has the potential to reduce the undesired side effects associated with faster release of drugs.Schematics for synthesis and application of magnetic nano-biocomposite for control release of DOX. 相似文献
998.
999.
New daily persistent headache (NDPH) is a subtype of chronic daily headache (CDH) that starts acutely and continues as a daily
headache from the onset. It is considered as one of the most treatment refractory of all headache syndromes. The pathophysiology
is largely unknown. Viral infections, extracranial surgery, and stressful life events are considered as triggers for the onset
of NDPH. A few patients may have the onset of their symptoms during an infection. Here we report nine patients with NDPH like
headache. All of them had a history suggestive of extracranial infections a few weeks prior to the onset of headache. All
patients received intravenous methyl prednisolone (IV MPS) for 5 days. Intravenous MPS was followed by Oral steroids for 2–3 weeks
in six patients. The relief of headache started between the second and fifth days of infusion in all patients. The steady
improvement in headache continued and seven patients experienced almost complete improvement within 2 weeks. Two other patients
showed complete improvement between 6 and 8 weeks after initiation of IV MPS therapy. We conclude that NDPH-like headache
may occur as a post infectious process following a recent infection. We also speculate on the possible mechanisms of headache
in our patients. 相似文献
1000.
Maria Irene Barillas-Lara Jose R. Medina-Inojosa Bhanu Prakash Kolla Joshua R. Smith Amanda R. Bonikowske Thomas G. Allison Thomas Olson Francisco Lopez-Jimenez Virend K. Somers Sean M. Caples Meghna P. Mansukhani 《Mayo Clinic proceedings. Mayo Clinic》2021,96(3):636-647
ObjectiveTo determine the risk of long-term major adverse cardiovascular events (MACE) when sleep-disordered breathing (SDB) and decreased cardiorespiratory fitness (CRF) co-occur.MethodsWe included consecutive patients who underwent symptom-limited cardiopulmonary exercise tests between January 1, 2005, and January 1, 2010, followed by first-time diagnostic polysomnography within 6 months. Patients were stratified based on the presence of moderate-to-severe SDB (apnea/hypopnea index ≥15 per hour) and decreased CRF defined as <70% predicted peak oxygen consumption (VO2). Long-term MACE was a composite outcome of myocardial infarction (MI), coronary artery bypass graft (CABG), percutaneous coronary intervention (PCI), stroke or transient ischemic attack (TIA), and death, assessed until May 21, 2018. Cox-proportional hazard models were adjusted for factors known to influence CRF and MACE.ResultsOf 498 included patients (60±13 years, 28.1% female), 175 (35%) had MACE (MI=17, PCI=14, CABG=13, stroke=20, TIA=12, deaths=99) at a median follow-up of 8.7 years (interquartile range=6.5 to 10.3 years). After adjusting for age, sex, beta blockers, systemic hypertension, diabetes mellitus, coronary artery disease, cardiac arrhythmia, chronic obstructive pulmonary disease, smoking, and use of positive airway pressure (PAP), decreased CRF alone (hazard ratio [HR]=1.91, 95% confidence interval [CI], 1.15 to 3.18; P=.01), but not SDB alone (HR=1.26, 95% CI, 0.75 to 2.13, P=.39) was associated with increased risk of MACE. Those with SDB and decreased CRF had greater risk of MACE compared with patients with decreased CRF alone (HR=1.85; 95% CI, 1.21 to 2.84; P<.005) after accounting for these confounders. The risk of MACE was attenuated in those with reduced CRF alone after additionally adjusting for adequate adherence to PAP (HR=1.59; 95% CI, 0.77 to 3.31; P=.21).ConclusionThe incidence of MACE, especially mortality, was high in this sample. Moderate-to-severe SDB with concurrent decreased CRF was associated with higher risk of MACE than decreased CRF alone. These results highlight the importance of possibly including CRF in the risk assessment of patients with SDB and, conversely, that of screening for SDB in patients with low peak VO2. 相似文献