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91.
The published literature on tooth transposition includes only a few studies that have involved more than 50 subjects. The aim of the present study was to investigate the prevalence of true maxillary tooth transposition and possible associated dental anomalies in a larger sample of children. The dental records and radiographs of children who had been diagnosed as having true maxillary tooth transposition at a School Dental Clinic in Hong Kong were studied retrospectively. Data were analyzed for sex and side distribution, as well as for associated dental anomalies. Trends of differences were analyzed statistically using the Fisher exact or chi-squared test. A total of 69 cases of true maxillary tooth transposition were identified and studied; its prevalence in Hong Kong Chinese children was 0.81%. More females than males were affected, and the difference between the sexes was statistically significant (P < 0.05). The prevalence of congenitally missing teeth, microdontia of the maxillary lateral incisors or dental impaction was higher in patients with maxillary tooth transposition than in the general population (P < 0.05, P < 0.0005, and P < 0.0001, respectively). The fact that patients with maxillary tooth transposition were more likely to have congenital absence or microdontia of the maxillary lateral incisors lent further support to the contention that a developmental field defect plays a role in the pathogenesis of maxillary tooth transposition. 相似文献
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94.
Youn Ho Shin Sun Jung Jang Jung Won Yoon Hye Mi Jee Sun Hee Choi Hye Yung Yum David Warburton Man Yong Han 《Canadian respiratory journal》2012,19(4):273-277
BACKGROUND:
Bronchodilator responses (BDR) are routinely used in the diagnosis and management of asthma; however, their acceptability and repeatability have not been evaluated using quality control criteria for preschool children.OBJECTIVES:
To compare conventional spirometry with an impulse oscillometry system (IOS) in healthy and asthmatic preschool children.METHODS:
Data from 30 asthmatic children and 29 controls (two to six years of age) who underwent IOS and spirometry before and after salbutamol administration were analyzed.RESULTS:
Stable asthmatic subjects significantly differed versus controls in their spirometry-assessed BDR (forced expiratory volume in 1 s [FEV1], forced vital capacity and forced expiratory flow at 25% to 75% of forced vital capacity) as well as their IOS-assessed BDR (respiratory resistance at 5 Hz [Rrs5], respiratory reactance at 5 Hz and area under the reactance curve). However, comparisons based on the area under the ROC curve for ΔFEV1 % initial versus ΔRrs5 % initial were 0.82 (95% CI 0.71 to 0.93) and 0.75 (95% CI 0.62 to 0.87), respectively. Moreover, the sensitivity and specificity for ΔFEV1 ≥9% were 0.53 and 0.93, respectively. Importantly, sensitivity increased to 0.63 when either ΔFEV1 ≥9% or ΔRrs5 ≥29% was considered as an additional criterion for the diagnosis of asthma.CONCLUSION:
The accuracy of asthma diagnosis in preschool children may be increased by combining spirometry with IOS when measuring BDR. 相似文献95.
Shaffiq A Haitchi HM Pang YY Alangari AA Jones MG Marshall BG Howarth PH Davies DE O'Reilly KM 《Respirology (Carlton, Vic.)》2012,17(2):342-349
Background and objective: A disintegrin and metalloproteinase (ADAM) 33 is a susceptibility gene associated with inflammatory lung and skin diseases. It is selectively expressed in mesenchymal cells, and its metalloprotease activity has been linked to angiogenesis and tissue remodelling. A soluble form of ADAM33 (sADAM33) has been identified in the bronchoalveolar lavage fluid (BALF) of asthmatic patients, and its levels inversely correlate with lung function. Because of its association with inflammatory lung diseases, it was hypothesized that sADAM33 is elevated in BALF of patients with pulmonary sarcoidosis. Methods: After removal of Ig using Protein A/G and enrichment using Concanavalin A beads, sADAM33 was identified in BALF by Western blotting. A fluorescence resonance energy transfer peptide cleavage assay was used to assess ADAM33‐like activity in BALF. Results: sADAM33 protein in BALF was detected as a 25 kDa fragment, and levels were significantly increased in samples from sarcoid patients when compared to healthy controls (P < 0.05). Levels of sADAM33 were inversely correlated with lung function (FVC%) (P < 0.05) and DLCO % predicted (P < 0.01). No difference in sADAM33 enzymatic activity was observed between healthy and sarcoid BALF samples. Conclusions: Release of sADAM33 is increased in sarcoid and may be associated with abnormal lung function. sADAM33 may be a biomarker of lung tissue inflammation and remodelling in sarcoid. 相似文献
96.
Bo Ram Kim So Hyun Kim JaeSang Ko Seung Woon Baek Yung Kyung Park Yoon Jung Kim Jin Sook Yoon 《Korean journal of ophthalmology : KJO》2021,35(1):37
PurposeWe sought to evaluate the safety and effectiveness of patient-specific ocular prostheses produced by three-dimensional (3D) printing and the sublimation technique. A comparison with prostheses produced using manual manufacturing methods was then performed.MethodsTo confirm the biological and physiochemical safety, cytotoxicity, systemic acute toxicity, intradermal reaction, and skin sensitization tests were conducted according to the International Organization for Standardization guidelines. The compressive strength of the prostheses was also tested. Further, a case series of three patients who wore the 3D printed prostheses for more than eight hours daily for 4 weeks was executed. Self-assessments by these individuals using a questionnaire and safety evaluations focusing on the occurrence of conjunctival inflammation or allergic reactions according to the Cornea and Contact Lens Research Unit criteria by slit-lamp examination and similarity assessment were completed.ResultsThe 3D printed ocular prostheses met the necessary qualifications per the biological and physiochemical safety tests, showing the absence of cytotoxicity, acute systemic toxicity, intradermal reactivity, and skin-sensitizing potency. Also, there was no difference in strength test results between previous ocular prostheses and the 3D printed ones. Self-assessment by the patients yielded satisfactory results, with no significant difference in the level of satisfaction reported for the 3D printed and previous handmade ocular prostheses. The 3D printed prosthesis did not trigger any side effects in the conjunctival sac and showed similar objective findings with respect to the color of the iris, sclera, and vessel patterns.ConclusionsOur study confirms the biologic and physiochemical safety of 3D-printed ocular prostheses created using computer-aided design technology and a sublimation technique. The patients’ questionnaires and the judgment of the ophthalmologists/ocularists showed that the 3D printed ocular prosthesis was acceptable in function and appearance through a case series report. 相似文献
97.
Steve W. N. Ueng Li‐Jen Yuan Song‐Shu Lin Chi‐Chien Niu Yi‐Sheng Chan I‐Chun Wang Chuen‐Yung Yang Wen‐Jer Chen 《Journal of orthopaedic research》2013,31(3):376-384
Heat shock proteins (HSPs), inflammatory cytokines, nitric oxide (NO), and localized hypoxia‐induced apoptosis are thought to be correlated to the degree of cartilage injury. We investigated the effect of hyperbaric oxygen (HBO) on (1) interleukin‐1β (IL‐1β)‐induced NO production and apoptosis of rabbit chondrocytes and (2) healing of articular cartilage defects. For the in vitro study, RT‐PCR and Western blotting were performed to detect mRNA and protein expressions of HSP70, inducible NO synthase (iNOS), and caspase 3 in IL‐1β‐treated chondrocytes. To clarify that the HSP70 was necessary for anti‐iNOS and anti‐apoptotic activity by HBO, we treated the cells with an HSP70 inhibitor, KNK437. For the in vivo study, cartilage defects were created in rabbits. The HBO group was exposed to 100% oxygen at 2.5 ATA for 1.5 h a day for 10 weeks. The control group was exposed to normal air. After sacrifice, specimen sections were sent for examination using a scoring system. Immunohistochemical analyses were performed to detect the expressions of iNOS, HSP70, and caspase 3. Our results suggested that HBO upregulated the mRNA and protein expressions of HSP70 and suppressed those of iNOS and caspase 3 in chondrocytes. KNK437 inhibited the HBO‐induced downregulation of iNOS and casapase 3 activities. The histological scores showed that HBO markedly enhanced cartilage repair. Immunohistostaining showed that HBO enhanced HSP70 expression and suppressed iNOS and caspase 3 expressions in chondrocytes. Accordingly, HBO treatment prevents NO‐induced apoptosis in articular cartilage injury via enhancement of the expression of heat shock protein 70. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 376–384, 2013 相似文献
98.
99.
Xiang‐Rong Sun Lei Chen Wen‐Fang Chen Yan Xue Wing‐Ho Yung 《Synapse (New York, N.Y.)》2013,67(12):831-838
The globus pallidus plays a critical role in movement regulation. Glutamate being an important excitatory neurotransmitter modulates the activity of pallidal neurons through both ionotropic and metabotropic glutamate receptors (mGluRs). Morphological studies have shown that group III mGluRs are generally located presynaptically in the globus pallidus. Up to now, little is known about the in vivo electrophysiological effects of group III mGluRs on the pallidal neurons. This study investigated the electrophysiological and behavioral effects of group III mGluRs on pallidal neurons in both normal and 6‐hydroxydopamine (6‐OHDA) lesioned parkinsonian rats. Micropressure ejection of group III mGluR agonist, l ‐2‐amino‐4‐phosphonobutyrate (l ‐AP4), increased or decreased the firing rate of pallidal neurons in both normal and parkinsonian rats. The l ‐AP4‐induced excitatory effects on the lesioned side of parkinsonian rats (117.4 ± 17.2%) were stronger than that in normal rats (64.3 ± 10.1%). While the proportion of neurons that were unresponsive to l ‐AP4 on the lesioned side of parkinsonian rats (50%) was more than that of normal rats (13%). Unilateral microinjection of l ‐AP4 into the globus pallidus induced a contralateral dystonic posturing in the presence of systemic haloperidol administration. The selective group III mGluRs antagonist, (RS)‐α‐cyclopropyl‐4‐phosphonophenylglycine, had no effect on pallidal neurons when used alone and could block both l ‐AP4‐induced electrophysiological and behavioral effects. Combining electrophysiological and behavioral findings, we concluded that activation of group III mGluRs modulate the activity of pallidal neurons under both normal and parkinsonian state. Synapse 67:831–838, 2013 . © 2013 Wiley Periodicals, Inc. 相似文献
100.
Eva Velthorst Barnaby Nelson Suzanne Wiltink Lieuwe de Haan Stephen J. Wood Ashleigh Lin Alison R. Yung 《Schizophrenia Research》2013,143(1):132-137
BackgroundBaseline functioning has been found to be a strong predictor of transition to psychosis in ultra high risk populations. However, the time course of functioning may enhance prediction. We investigated whether there were different patterns of functioning over time and whether particular temporal patterns were related to baseline characteristics and psychosis outcome.MethodFunctional data was assessed at baseline and after 3 to 6 year follow-up in an ultra high risk sample (n = 158; 92 female, mean age = 19.28 (SD = 3.33), range = 14–29). Using the median score of the GAF and the QLS scale, a ‘High’ and ‘Low’ group (comprising of subjects functioning above or below median at both baseline and follow-up) and a ‘Deterioration’ group and ‘Improving’ group were created.ResultsChi-square analyses showed that the Low and Deteriorating functioning groups were the most likely to develop first-episode psychosis (FEP). Importantly, UHR individuals with deteriorating functioning were at higher risk of transition than those whose functioning was low at baseline but improved over time (GAF: X2 = 5.10, df = 1, p = .02; QLS: X2 = 9.13, df = 1, p = .003). Binary logistic regression analyses showed that a decline in functioning was more strongly associated with FEP (GAF: p = < .0001; QLS: p < .0001) than the level of baseline functioning (GAF: p = .005; QLS: p = .09). The deteriorating group could not be distinguished from the High group in terms of baseline symptomatology.DiscussionWith the addition of the ‘low functioning’ criterion to the UHR criteria, we may miss out on some true positive cases. Limiting our attention to baseline poor functioning may therefore distort the picture in terms of risk for psychosis. 相似文献