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排序方式: 共有354条查询结果,搜索用时 15 毫秒
91.
Ana ZN Bergamo Paulo Nelson-Filho Fábio L Romano Raquel AB da Silva Maria CP Saraiva Lea AB da Silva 《Journal of orthodontics》2016,43(4):260-267
Objective: The aim of this study was to evaluate the alterations on plaque index (PI), gingival index (GI), gingival bleeding index (GBI), and gingival crevicular fluid (GCF) volume after use of three different brackets types for 60 days. Setting Participants: The sample comprised 20 patients of both sexes aged 11–15 years (mean age: 13.3 years), with permanent dentition, adequate oral hygiene, and mild tooth crowding, overjet, and overbite. Methods: A conventional metallic bracket Gemini?, and two different brands of self-ligating brackets — In-Ovation®R and SmartClip? — were bonded to the maxillary incisors and canines. PI, GI, GBI scores, and GCF volume were measured before and 30 and 60 days after bonding of the brackets. Data were analysed statistically using non-parametric tests coefficient at a 5% significance level. Results: There was no statistically significant correlation (P?>?0.05) between tooth crowding, overjet, and overbite and the PI, GI, GBI scores, and GCF volume before bonding, indicating no influence of malocclusion on the clinical parameters. Regardless of the bracket design, no statistically significant difference (P?>?0.05) was found for GI, GBI scores. PI and GCF volume showed a significant difference among the brackets in different periods. In pairwise comparisons a significant difference was observed when compared before with 60 days after bonding, for the teeth bonded with SmartClip? self-ligating bracket, (PI P?=?0.009; GCF volume P?=?0.001). Conclusion: There was an increase in PI score and GCF volume 60 days after bonding of SmartClip? self-ligating brackets, indicating the influence of bracket design on these clinical parameters. 相似文献
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Alim Hirji Alessandra Bernasconi Brian W McCrindle Elizabeth Dunn Rebecca Gurofsky Cedric Manlhiot Steven ES Miner John CP Kingdom Edgar T Jaeggi Glen Van Arsdell Lynne E Nield 《The Canadian journal of cardiology》2010,26(1):e1-e6
OBJECTIVES:
To assess outcomes of prenatally diagnosed tetralogy of Fallot and determine factors associated with the choice to undergo a valve-sparing repair versus transannular patch, and the use of prostaglandins at birth.METHODS:
All cases at The Hospital for Sick Children (Toronto, Ontario) with a fetal diagnosis of tetralogy of Fallot from 1998 to 2006, were reviewed for demographic and fetal echocardiographic data to determine factors associated with the valve-sparing repair and need for perinatal support.RESULTS:
Sixty-four fetuses met inclusion criteria (median gestational age 22 weeks) with 47 live births. Twenty-six underwent valve-sparing repair (median age 5.7 months) and 14 underwent transannular patch repair (median age 4.5 months). There were seven deaths before surgery and one post-transannular patch repair. One patient required a transannular patch repair after the initial valve-sparing repair. Twelve of 29 (41%) patients received prostaglandins at birth. Type of surgical repair, use of prostaglandins and postnatal death were among the outcomes investigated. The mean pulmonary valve (PV) z-score was −3.0±2.0 and the mean PV/aortic valve (AoV) ratio was 0.65±0.10. Lower PV z-score (P=0.04), smaller PV/AoV ratio (P=0.04) and the presence of nonantegrade arterial duct flow (P=0.02) were associated with prostaglandin use. A higher PV/AoV ratio was associated with valve-sparing repair (P=0.04). Fetal z-scores of the PV, AoV and right pulmonary artery at 29 to 32 weeks gestational age correlated with respective postnatal z-scores (P=0.01).CONCLUSION:
Fetal echocardiographic variables were associated with the use of prostaglandins and valve-sparing repair in fetuses with tetralogy of Fallot, and at 29 weeks, correlated with postnatal valve diameters. 相似文献95.
96.
Background
General Practitioners spend a disproportionate amount of time on frequent attenders. So far, trials on the effect of interventions on frequent attenders have shown negative results. However, these trials were conducted in short-term frequent attenders. It would be more reasonable to target intervention at persistent frequent attenders. Typical characteristics of persistent frequent attenders, as opposed to 1-year frequent attenders and non-frequent attenders, may generate hypotheses regarding modifiable factors on which new randomized trials may be designed. 相似文献97.
CP Bailey S Oldfield J Llorente CJ Caunt AG Teschemacher L Roberts CA McArdle FL Smith WL Dewey E Kelly G Henderson 《British journal of pharmacology》2009,158(1):157-164
Background and purpose:
The ability of an agonist to induce desensitization of the µ-opioid receptor (MOR) depends upon the agonist used. Furthermore, previous data suggest that the intracellular mechanisms underlying desensitization may be agonist-specific. We investigated the mechanisms underlying MOR desensitization, in adult mammalian neurons, caused by morphine (a partial agonist in this system) and DAMGO (a high-efficacy agonist).Experimental approach:
MOR function was measured in locus coeruleus neurons, by using whole-cell patch-clamp electrophysiology, in rat and mouse brain slices (both wild-type and protein kinase C (PKC)α knockout mice). Specific isoforms of PKC were inhibited by using inhibitors of the receptors for activated C-kinase (RACK), and in vivo viral-mediated gene-transfer was used to transfect neurons with dominant negative mutants (DNMs) of specific G-protein-coupled receptor kinases (GRKs).Key results:
Morphine-induced desensitization was attenuated by using RACK inhibitors that inhibit PKCα, but not by other isoform-specific inhibitors. Further, the PKC component of morphine-induced desensitization was absent in locus coeruleus neurons from PKCα knockout mice. The PKC-enhanced morphine-induced desensitization was not affected by over-expression of a GRK2 dominant negative mutant (GRK2 DNM). In contrast, DAMGO-induced MOR desensitization was independent of PKC activity but was reduced by over-expression of the GRK2 DNM but not by that of a GRK6 DNM.Conclusions and implications:
In mature mammalian neurons, different MOR agonists can induce MOR desensitization by different mechanisms, morphine by a PKCα-mediated, heterologous mechanism and DAMGO by a GRK-mediated, homologous mechanism. These data represent functional selectivity at the level of receptor desensitization. 相似文献98.
Background
Pueraria lobata flower (Gehua) is a medicinal herb to treat intoxication, hepatic and gastrointestinal tract lesion induced by alcohol. This study aims to develop a new HPLC method for the determination of two major isoflavones in P. lobata flowers, namely tectoridin and 6"-O-xylosyl-tectoridin. 相似文献99.
CP Carlsson J Wallengren 《Journal of the European Academy of Dermatology and Venereology》2010,24(9):1013-1016
Itch accompanies most inflammatory skin diseases but may occur as a solitary sensation in otherwise normal skin. Chronic itch often requires combined treatments but some cases remain therapy resistant. Complementary medicine is becoming increasingly popular among patients. Acupuncture is the oldest and most well‐studied alternative option with evidence‐based effect on pain. This article summarizes the rational for the use of acupuncture in treatment of itch and reviews therapeutic and experimental therapeutic studies on acupuncture and itch. 相似文献
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