The 10%Ni/Al_2O_3 catalyst for partial oxidation of methane was treated byDBD (dielectric barrier discharge) plasma in a continuous system under atmospheric pressure and roomtemperature by flowing He. It was found tha...The 10%Ni/Al_2O_3 catalyst for partial oxidation of methane was treated byDBD (dielectric barrier discharge) plasma in a continuous system under atmospheric pressure and roomtemperature by flowing He. It was found that 10%Ni/Al_2O_3 catalyst treated by plasma presents ahigher catalytic activity and an enhanced stability than the catalysts prepared without plasmatreatment. The methane conversion over the catalyst treated by plasma is 3%-5% higher than thecatalysts untreated by plasma. Moreover, the enhanced dispersion of the catalyst can be achieved byplasma treatment, which can improve the interaction between active species and supports, catalyticactivity and the resistance to carbon deposition.展开更多
Dental materials have been continuously developing over a long period of time. Every effort has been made to develop the physical and mechanical properties of the materials to mimic the natural tooth substances. Howev...Dental materials have been continuously developing over a long period of time. Every effort has been made to develop the physical and mechanical properties of the materials to mimic the natural tooth substances. However, that has not yet been achieved, making it necessary to apply conservative dental treatments. Conservative treatments are procedures which minimize the amount of defective tooth structure removed while maximizing the remaining amount of intact tooth structure, and defining the margin of the restoration at the supragingival level. In a substantially destructed tooth, the direct restoration, which is the most conservative restoration, has the limitations on the retention or creation of the proper contour of the restoration. The indirectly partial coverage restoration has recently gained in popularity. This treatment preserves the tooth structure while allowing reconstruction of the destructed structure to enable correct and proper tooth functioning and also provides a satisfactory cosmetic appearance. The purpose of this paper is to review and compare the various conservative techniques of partial coverage restorations and the full coverage treatment with crowns.展开更多
The effect of subzero treatment on the microstructure and mechanical properites of Y_2O_3- ZrO_2 ceramic have been investigated by TEM,X-ray diffraction and test of mechanical properties.It was shown that the microstr...The effect of subzero treatment on the microstructure and mechanical properites of Y_2O_3- ZrO_2 ceramic have been investigated by TEM,X-ray diffraction and test of mechanical properties.It was shown that the microstructre of 3Y-PSZ after subzero treatment by liquid nitrogen exhibits very long and parallel laths of m-phase and some microcracks around the larger and finer lath of m-phase may be discovered.Suitable subzero treatment can improve the strength and toughness of Y-PSZ efficiently because of decreasing the stability of t-phase and incresing the amount of t-m transformation when exerting a stress.However,when the time of subzero treatment exceeds,the over aging effect may arise.which can decrease the strength and toughness of the material.展开更多
AIM: To review evidence supporting pharmacological treatments for treatment-resistant depression(TRD) and to discuss them according to personal clinical experience.METHODS: Original studies, clinical trials, systemati...AIM: To review evidence supporting pharmacological treatments for treatment-resistant depression(TRD) and to discuss them according to personal clinical experience.METHODS: Original studies, clinical trials, systematic reviews, and meta-analyses addressing pharmacological treatment for TRD in adult patients published from 1990 to 2013 were identified by data base queries(Pub Med, Google Scholar e Quertle Searches) using terms: "treatment resistant depression", "treatment refractory depression", "partial response depression", "non responder depression", "optimization strategy", "switching strategy", "combination strategy", "augmentation strategy", selective serotonin reuptake inhibitors antidepressants(SSRI), tricyclic antidepressants(TCA), serotonin norepinephrine reuptake inhibitors antidepressants, mirtazapine, mianserine, bupropione, monoamine oxidase inhibitor antidepressant(MAOI), lithium, thyroid hormones, second generation antipsychotics(SGA), dopamine agonists, lamotrigine, psychostimulants, dextromethorphan, dextrorphan, ketamine, omega-3 fatty acids, S-adenosil-L-metionine, methylfolat, pindolol, sex steroids, glucocorticoid agents. Other citations of interest were further identified from references reported in the accessed articles. Selected publications were grouped by treatment strategy:(1) switching from an ineffective antidepressant(AD) to a new AD from a similar or different class;(2) combining the current AD regimen with a second AD from a different class; and(3) augmenting the current AD regimen with a second agent not thought to be an antidepressant itself.RESULTS: Switching from a TCA to another TCA provides only a modest advantage(response rate 9%-27%), while switching from a SSRI to another SSRI is more advantageous(response rate up to 75%). Evidence supports the usefulness of switching from SSRI to venlafaxine(5 positive trials out 6), TCA(2 positive trials out 3), and MAOI(2 positive trials out 2) but not from SSRI to bupropione, duloxetine and mirtazapine. Three reviews demonstrated that the benefits of intraand cross-class switch do not significantly differ. Data on combination strategy are controversial regarding TCA-SSRI combination(positive results in old studies, negative in more recent study) and bupropion-SSRI combination(three open series studies but not three controlled trails support the useful of this combination) and positive regard mirtazapine(or its analogue mianserine) combination with ADs of different classes. As regards the augmentation strategy, available evidences supported the efficacy of TCA augmentation with lithium salts and thyroid hormone(T3), but are conflicting regard the SSRI augmentation with these two drugs(1 positive trial out of 4 for lithium and 3 out of 5 for thyroid hormone). Double-blind controlled studies showed the efficacy of AD augmentation with aripiprazole(5 positive trials out 5), quetiapine(3 positive trials out 3) and, at less extent, of fluoxetine augmentation with olanzapine(3 positive trials out 6), so these drugs received the FDA indication for the acute treatment of TRD. Results on AD augmentation with risperidone are conflicting(2 short term positive trials, 1 short-term and 1 long-term negative trials). Case series and open-label trials showed that AD augmentation with pramipexole or ropinirole, two dopamine agonists, could be an effective treatment for TRD(response rate to pramipexole 48%-74%, to ropinirole 40%-44%) although one recent double-blind placebo-controlled study does not support the superiority of pramipexole over placebo. Evidences do not justify the use of psychostimulants, omega-3 fatty acids, S-adenosil-Lmetionine, methylfolate, pindolol, lamotrigine, and sex hormone as AD augmentation for TRD. Combining the available evidences with our experience we suggest treating non-responders to one SSRI bupropion or mirtazapine trial by switching to venlafaxine, and nonresponders to one venlafaxine trial by switching to a TCA or, if TCA are not tolerated, combining mirtazapine with SSRI or venlafaxine. In non-responders to two or more ADs(including at least one TCA if tolerated) current AD regimen could be augmented with lithium salts(mainly in patients with bipolar depression or suicidality), SGAs(mostly aripiprazole) or DA-agonists(mostly pramipexole). In patients with severe TRD, i.e., non-responders to combination and augmentation strategies as well as to electroconvulsive therapy if workable, we suggest to try a combination plus augmentation strategy.CONCLUSION: Our study identifies alternative effective treatment strategies for TRD. Further studies are needed to compare the efficacy of different strategies in more homogeneous subpopulations.展开更多
基金This work was supported by National Science Foundation Committee of China (Grant number 20106013).
文摘The 10%Ni/Al_2O_3 catalyst for partial oxidation of methane was treated byDBD (dielectric barrier discharge) plasma in a continuous system under atmospheric pressure and roomtemperature by flowing He. It was found that 10%Ni/Al_2O_3 catalyst treated by plasma presents ahigher catalytic activity and an enhanced stability than the catalysts prepared without plasmatreatment. The methane conversion over the catalyst treated by plasma is 3%-5% higher than thecatalysts untreated by plasma. Moreover, the enhanced dispersion of the catalyst can be achieved byplasma treatment, which can improve the interaction between active species and supports, catalyticactivity and the resistance to carbon deposition.
文摘Dental materials have been continuously developing over a long period of time. Every effort has been made to develop the physical and mechanical properties of the materials to mimic the natural tooth substances. However, that has not yet been achieved, making it necessary to apply conservative dental treatments. Conservative treatments are procedures which minimize the amount of defective tooth structure removed while maximizing the remaining amount of intact tooth structure, and defining the margin of the restoration at the supragingival level. In a substantially destructed tooth, the direct restoration, which is the most conservative restoration, has the limitations on the retention or creation of the proper contour of the restoration. The indirectly partial coverage restoration has recently gained in popularity. This treatment preserves the tooth structure while allowing reconstruction of the destructed structure to enable correct and proper tooth functioning and also provides a satisfactory cosmetic appearance. The purpose of this paper is to review and compare the various conservative techniques of partial coverage restorations and the full coverage treatment with crowns.
文摘The effect of subzero treatment on the microstructure and mechanical properites of Y_2O_3- ZrO_2 ceramic have been investigated by TEM,X-ray diffraction and test of mechanical properties.It was shown that the microstructre of 3Y-PSZ after subzero treatment by liquid nitrogen exhibits very long and parallel laths of m-phase and some microcracks around the larger and finer lath of m-phase may be discovered.Suitable subzero treatment can improve the strength and toughness of Y-PSZ efficiently because of decreasing the stability of t-phase and incresing the amount of t-m transformation when exerting a stress.However,when the time of subzero treatment exceeds,the over aging effect may arise.which can decrease the strength and toughness of the material.
文摘AIM: To review evidence supporting pharmacological treatments for treatment-resistant depression(TRD) and to discuss them according to personal clinical experience.METHODS: Original studies, clinical trials, systematic reviews, and meta-analyses addressing pharmacological treatment for TRD in adult patients published from 1990 to 2013 were identified by data base queries(Pub Med, Google Scholar e Quertle Searches) using terms: "treatment resistant depression", "treatment refractory depression", "partial response depression", "non responder depression", "optimization strategy", "switching strategy", "combination strategy", "augmentation strategy", selective serotonin reuptake inhibitors antidepressants(SSRI), tricyclic antidepressants(TCA), serotonin norepinephrine reuptake inhibitors antidepressants, mirtazapine, mianserine, bupropione, monoamine oxidase inhibitor antidepressant(MAOI), lithium, thyroid hormones, second generation antipsychotics(SGA), dopamine agonists, lamotrigine, psychostimulants, dextromethorphan, dextrorphan, ketamine, omega-3 fatty acids, S-adenosil-L-metionine, methylfolat, pindolol, sex steroids, glucocorticoid agents. Other citations of interest were further identified from references reported in the accessed articles. Selected publications were grouped by treatment strategy:(1) switching from an ineffective antidepressant(AD) to a new AD from a similar or different class;(2) combining the current AD regimen with a second AD from a different class; and(3) augmenting the current AD regimen with a second agent not thought to be an antidepressant itself.RESULTS: Switching from a TCA to another TCA provides only a modest advantage(response rate 9%-27%), while switching from a SSRI to another SSRI is more advantageous(response rate up to 75%). Evidence supports the usefulness of switching from SSRI to venlafaxine(5 positive trials out 6), TCA(2 positive trials out 3), and MAOI(2 positive trials out 2) but not from SSRI to bupropione, duloxetine and mirtazapine. Three reviews demonstrated that the benefits of intraand cross-class switch do not significantly differ. Data on combination strategy are controversial regarding TCA-SSRI combination(positive results in old studies, negative in more recent study) and bupropion-SSRI combination(three open series studies but not three controlled trails support the useful of this combination) and positive regard mirtazapine(or its analogue mianserine) combination with ADs of different classes. As regards the augmentation strategy, available evidences supported the efficacy of TCA augmentation with lithium salts and thyroid hormone(T3), but are conflicting regard the SSRI augmentation with these two drugs(1 positive trial out of 4 for lithium and 3 out of 5 for thyroid hormone). Double-blind controlled studies showed the efficacy of AD augmentation with aripiprazole(5 positive trials out 5), quetiapine(3 positive trials out 3) and, at less extent, of fluoxetine augmentation with olanzapine(3 positive trials out 6), so these drugs received the FDA indication for the acute treatment of TRD. Results on AD augmentation with risperidone are conflicting(2 short term positive trials, 1 short-term and 1 long-term negative trials). Case series and open-label trials showed that AD augmentation with pramipexole or ropinirole, two dopamine agonists, could be an effective treatment for TRD(response rate to pramipexole 48%-74%, to ropinirole 40%-44%) although one recent double-blind placebo-controlled study does not support the superiority of pramipexole over placebo. Evidences do not justify the use of psychostimulants, omega-3 fatty acids, S-adenosil-Lmetionine, methylfolate, pindolol, lamotrigine, and sex hormone as AD augmentation for TRD. Combining the available evidences with our experience we suggest treating non-responders to one SSRI bupropion or mirtazapine trial by switching to venlafaxine, and nonresponders to one venlafaxine trial by switching to a TCA or, if TCA are not tolerated, combining mirtazapine with SSRI or venlafaxine. In non-responders to two or more ADs(including at least one TCA if tolerated) current AD regimen could be augmented with lithium salts(mainly in patients with bipolar depression or suicidality), SGAs(mostly aripiprazole) or DA-agonists(mostly pramipexole). In patients with severe TRD, i.e., non-responders to combination and augmentation strategies as well as to electroconvulsive therapy if workable, we suggest to try a combination plus augmentation strategy.CONCLUSION: Our study identifies alternative effective treatment strategies for TRD. Further studies are needed to compare the efficacy of different strategies in more homogeneous subpopulations.
