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排序方式: 共有270条查询结果,搜索用时 62 毫秒
261.
Patients presenting with severe resorption of the residual alveolar ridges are relatively common today in both private practices and teaching institutions. The severely resorbed mandibular ridge is more challenging to impress than is the maxillary ridge. Accurately capturing the denture-bearing surface in its entirety is crucial to providing the patient with a functionally successful prosthesis. This article presents a technique to overcome the difficulties encountered in impressing the severely resorbed mandibular ridge using elastomeric impression materials and a modified special custom tray. 相似文献
262.
Ajay Pratap Singh Rula Balluz Praveen Chandrasekharan 《Heart & lung : the journal of critical care》2018,47(2):162-165
Background
At three weeks of age, a previous 34 weeks' gestation male infant (twin A) was transferred to our regional perinatal center (RPC) with complaints of poor oral feeding and intermittent tachypnea. Twin B was discharged at 37 weeks with an uneventful course.Case
Twin A briefly required respiratory support but continued to have difficulty transitioning from gavage to oral feeding. Initially, his inability to feed orally was thought to be secondary to nasal congestion and prematurity, but with worsening respiratory distress he was transferred for further evaluation and management.Diagnosis & Conclusion
On admission to RPC, the examination prompted a cardiac assessment which revealed a large aortic-pulmonary window type II. After surgery, the infant quickly improved and went home on-demand oral feeds. Cardiac lesions are more common in monochorionic twins but should be suspected in dichorionic twins especially if one twin has a normal course. 相似文献263.
Jie Fang Prashant Chandrasekharan Xiao-Li Liu Yong Yang Yun-Bo Lv Chang-Tong Yang Jun Ding 《Biomaterials》2014
In this report, monodispersed ultra-small Gd2O3 nanoparticles capped with hydrophobic oleic acid (OA) were synthesized with average particle size of 2.9 nm. Two methods were introduced to modify the surface coating to hydrophilic for bio-applications. With a hydrophilic coating, the polyvinyl pyrrolidone (PVP) coated Gd2O3 nanoparticles (Gd2O3-PVP) showed a reduced longitudinal T1 relaxation time compared with OA and cetyltrimethylammonium bromide (CTAB) co-coated Gd2O3 (Gd2O3-OA-CTAB) in the relaxation study. The Gd2O3-PVP was thus chosen for its further application study in MRI with an improved longitudinal relaxivity r1 of 12.1 mm−1 s−1 at 7 T, which is around 3 times as that of commercial contrast agent Magnevist®. In vitro cell viability in HK-2 cell indicated negligible cytotoxicity of Gd2O3-PVP within preclinical dosage. In vivo MR imaging study of Gd2O3-PVP nanoparticles demonstrated considerable signal enhancement in the liver and kidney with a long blood circulation time. Notably, the OA capping agent was replaced by PVP through ligand exchange on the Gd2O3 nanoparticle surface. The hydrophilic PVP grants the Gd2O3 nanoparticles with a polar surface for bio-application, and the obtained Gd2O3-PVP could be used as an in vivo indicator of reticuloendothelial activity. 相似文献
264.
Pauschinger M Rutschow S Chandrasekharan K Westermann D Weitz A Peter Schwimmbeck L Zeichhardt H Poller W Noutsias M Li J Schultheiss HP Tschope C 《European journal of heart failure》2005,7(4):444-452
BACKGROUND: Proinflammatory cytokines induce the expression of matrix metalloproteinases that play a crucial role in myocardial remodeling. Beta-adrenergic receptor stimulation influences the production of cytokines heralding the possibility of modulating cytokine production by beta-adrenergic blockers. METHODS AND RESULTS: In a coxsackievirus B3 murine myocarditis model (BALB/c), effects of carvedilol and metoprolol on myocardial cytokine expression, inflammatory cell infiltration and MMP/TIMP profiles were investigated. In carvedilol-treated mice, a significant improvement in left ventricular function was documented 10 days post infection. In infected mice (n=10), IL-1beta, TNF-alpha, TGF-beta(1) and IL-10 myocardial mRNA abundance were increased significantly (240%, 200%, 161%, and 230%) compared to controls (n=10), while IL-15 mRNA was markedly reduced (70%). Infected mice showed significantly increased infiltrations with CD3-, CD4- and CD8-T-lymphocytes (730%, 1110%, 380%). In the infected mice, myocardial MMP/TIMP profiles presented a significant upregulation of membrane type-1 MMP, MMP-9, MMP-8 and MMP-3 (150%, 160%, 340%, and 270%) and a significant decrease in TIMP-4 levels (75%). Carvedilol attenuated over-expression of myocardial TGF-beta(1), IL-1beta and MMP-8 mRNA expression significantly and induced a relevant IL-10 mRNA expression in the infected mice (n=10). By an unchanged infiltration with CD3-T-lymphocytes, carvedilol showed a representative reduction in CD4-T-lymphocytes. CONCLUSION: Carvedilol treatment in experimental myocarditis leads to reduced expression of proinflammatory cytokines and MMPs, which contributes to reduced matrix degradation and ultimately to improved structural integrity of the heart. Besides the antiadrenergic potential, carvedilol is beneficial due to a wide range of biological activities (antiinflammatory, antifibrotic, antioxidative and immunomodulatory). 相似文献
265.
Biophytum sensitivum has been used in traditional folk medicine to treat numerous diseases. The molecular mechanism of B. sensitivum pharmacological and biochemical actions of macrophages in inflammation has not been clearly elucidated. We examined how the methanol extract of B. sensitivum regulates the production of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6, and nitric oxide (NO) in vitro and in vivo. The extract inhibits the production of NO and proinflammatory cytokines in lipopolysaccharide (LPS) or Concanavalin (Con) A-stimulated primary macrophages. In vitro L929 bioassay revealed the inhibition of TNF-α production by B. sensitivum treatment. Moreover, the extract could suppress the inducible nitric oxide synthase and cyclo-oxygenase-2 mRNA expression in LPS or Con A-stimulated macrophages. These findings provide evidence that B. sensitivum possesses potential anti-inflammatory activity and may be beneficial for the treatment of endotoxin shock or sepsis. 相似文献
266.
Aishwarya Sooresh Zhirui Zeng Jayashree Chandrasekharan Suresh D. Pillai Christie M. Sayes 《Food and chemical toxicology》2012
Colloids on the nanometer size scale are beginning to find increased applications in drinks, foods, food-contact surfaces, and food packaging. While these particles add intrinsic value to the food industry, their potential toxicities warrant careful studies. The physicochemical changes and possible perturbations to microbial communities within the gastrointestinal tract have not been adequately studied. The purpose of this study was to design and perform a simulated digestion protocol to evaluate the effect of colloidal silver in an orange juice suspension when exposed to planktonic bacterial cultures and biofilms. The model system includes four precursor steps in which the silver is exposed to varying pH conditions and incubation times. The gastrointestinally “digested” samples were then incubated with Escherichia coli strains for up to 4 h, the average residence time of foods in the GI tract. The physicochemical changes of the colloids and their corresponding biological effects were characterized at every step. The results showed differences between (1) bacterial cultures versus bacterial biofilms, (2) “digested” versus “undigested” silver on bacteria, and (3) differences between “digested” silver nitrate versus silver colloids on bacteria. We conclude that simulated digestion, as well as manner in which bacterial cells are grown, influences the results of toxicity. 相似文献
267.
Biophytum sensitivum has been used in traditional folk medicine to treat numerous diseases. The molecular mechanism of B. sensitivum pharmacological and biochemical actions of macrophages in inflammation has not been clearly elucidated. We examined how the methanol extract of B. sensitivum regulates the production of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-6, and nitric oxide (NO) in vitro and in vivo. The extract inhibits the production of NO and proinflammatory cytokines in lipopolysaccharide (LPS) or Concanavalin (Con) A-stimulated primary macrophages. In vitro L929 bioassay revealed the inhibition of TNF-alpha production by B. sensitivum treatment. Moreover, the extract could suppress the inducible nitric oxide synthase and cyclo-oxygenase-2 mRNA expression in LPS or Con A-stimulated macrophages. These findings provide evidence that B. sensitivum possesses potential anti-inflammatory activity and may be beneficial for the treatment of endotoxin shock or sepsis. 相似文献
268.
McVicar AJ Greenwood CR Fewell F D'Arcy V Chandrasekharan S Alldridge LC 《Complementary therapies in clinical practice》2007,13(3):137-145
This pilot study sought to identify an appropriate methodology to investigate the impact of reflexology in healthcare settings. The study involved healthy volunteers to prevent unnecessary intervention to individuals who may already be experiencing health related trauma. Thirty participants underwent either reflexology or no treatment (control), in a cross-over experimental design. Self-reported anxiety (Spielberger STAI), cardiovascular parameters (BP and pulse rate) and salivary cortisol and melatonin concentrations were assessed before and after reflexology. Control data were obtained at the same time points in identical settings. Reflexology had a powerful anxiety-reduction effect ('state'; P<0.001) but no significant effect on underlying anxiety ('trait'). Cardiovascular parameters decreased (P<0.001). Baseline salivary cortisol and melatonin were not significantly correlated with STAI scores and did not change significantly following reflexology. Reflexology reduced 'state' anxiety and cardiovascular activity within healthy individuals, consistent with stress-reduction. Considering the connection between stress/anxiety and well being, the effects of reflexology may have beneficial outcomes for patients. These findings will be transferred to a study involving breast cancer patients where effects may be more pronounced particularly since cancer patients display disregulation of cortisol and melatonin secretion. 相似文献
269.
270.
Tan YF Chandrasekharan P Maity D Yong CX Chuang KH Zhao Y Wang S Ding J Feng SS 《Biomaterials》2011,32(11):2969-2978
This work developed a multimodal imaging system by co-encapsulating superparamagnetic iron oxides (IOs) and quantum dots (QDs) in the nanoparticles of poly (lactic acid) - d-α-tocopheryl polyethylene glycol 1000 succinate (PLA-TPGS) for concurrent imaging of the magnetic resonance imaging (MRI) and the fluorescence imaging to combine their advantages and to overcome their disadvantages as well as to promote a sustained and controlled imaging with passive targeting effects to the diseased cells. The QDs and IOs-loaded PLA-TPGS NPs were prepared by a modified nanoprecipitation method, which were then characterized for their size and size distribution, zeta potential and the imaging agent encapsulation efficiency. The transmission electron microscopy (TEM) images showed direct evidence for the well-dispersed distribution of the QDs and IOs within the PLA-TPGS NPs. The cellular uptake and the cytotoxicity of the PLA-TPGS NPs formulation of QDs and IOs were investigated in vitro with MCF-7 breast cancer cells, which were conducted in close comparison with the free QDs and IOs at the same agent dose. The Xenograft model was also conducted for biodistribution of the QDs and IOs-loaded PLA-TPGS NPs among the various organs, which showed greatly enhanced tumor imaging due to the passively targeting effects of the NPs to the tumor. Images of tumors were acquired in vivo by a 7T MRI scanner. Further ex vivo images of the tumors were obtained by confocal laser scanning microscopy. Such a multimodal imaging system shows great advantages of both contrast agents making the resultant probe highly sensitive with good depth penetration, which confirms the diagnosis obtained from each individual imaging. With therapeutics co-encapsulation and ligand conjugation, such nanoparticles system can realize a multi-functional system for medical diagnosis and treatment. 相似文献