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21.
根管治疗术远期疗效的影响因素 总被引:6,自引:1,他引:5
根管治疗术(root canal therapy,RCT)是治疗牙髓病、根尖周病的主要方法.影响根管治疗术远期疗效的因素较多,而RCT前根尖周状态和根充位置是两大主要因素. 相似文献
22.
Pituitary stalk meningioma: case report 总被引:1,自引:0,他引:1
We report a 45-year-old woman with a meningioma which was in contact with only the pituitary stalk on MRI. As the pituitary
stalk has no dura mater, we suggest this tumour may have originated from the arachnoid membrane of the pituitary stalk. Though
some reports have shown that meningiomas can arise from sites lacking a dural component, this is the first report of a meningioma
originating from the pituitary stalk.
Received: 21 December 1995 Accepted: 26 February 1996 相似文献
23.
Abstract Maxillary and mandibular anterior permanent teeth in 38 children aged 7–12 years were examined 2 × with an interval of 2 years to determine whether spontaneous facial/lingual tooth position changes were related to alterations of the widths of keratinized and attached gingiva and the clinical crown height. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study casts from the baseline and 2-year examinations were used to measure clinical crown height and tooth position. The results showed that significant alterations in the widths of the keratinized and attached gingiva took place when the teeth changed positions in facial or lingual directions. The changes in gingival widths could to some extent be coupled to changes in clinical crown height. In teeth moving lingually, the gingival widths increased and the clinical crown height decreased. In teeth moving facially, the gingival widths decreased, and the facial gingiva sometimes receded. These gingival alterations call for examination of the facial gingiva as part of the monitoring of the development of the permanent dentition. 相似文献
24.
第二产程产妇自由体位分娩效果的研究 总被引:8,自引:0,他引:8
目的 探讨产妇在第二产程中采取自由体位对分娩效果及舒适瘦的影响。方法 随机将152例初产妇分为观察组77例和对照组75例。观察组产妇在第二产程根据产妇的意愿采取半卧位、侧卧位、蹲位、坐位等自由体位,接生时采用半卧蹲坐位。对照组产妇采取床头抬高30°的截石位分娩。比较2组第二产程的长度及产后的舒适度。结果 观察组第二产程较对照组缩短(P〈0.01),产后双下肢酸痛、麻木不适较对照组显著减轻,舒适度增加。结论 第二产程自由体位可有效缩短产程并缓解分娩体位的不适。 相似文献
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27.
The seven serotypes (A–G) of botulinum neurotoxin (BoNT) are proteins produced by Clostridium botulinum and have multifunctional abilities: (i) they target cholinergic nerve endings via binding to ecto‐acceptors (ii) they undergo endocytosis/translocation and (iii) their light chains act intraneuronally to block acetylcholine release. The fundamental process of quantal transmitter release occurs by Ca2+‐regulated exocytosis involving sensitive factor attachment protein‐25 (SNAP‐25), syntaxin and synaptobrevin. Proteolytic cleavage by BoNT‐A of nine amino acids from the C‐terminal of SNAP‐25 disables its function, causing prolonged muscle weakness. This unique combination of activities underlies the effectiveness of BoNT‐A haemagglutinin complex in treating human conditions resulting from hyperactivity at peripheral cholinergic nerve endings. In vivo imaging and immunomicroscopy of murine muscles injected with type A toxin revealed that the extended duration of action results from the longevity of its protease, persistence of the cleaved SNAP‐25 and a protracted time course for the remodelling of treated nerve–muscle synapses. In addition, an application in pain management has been indicated by the ability of BoNT to inhibit neuropeptide release from nociceptors, thereby blocking central and peripheral pain sensitization processes. The widespread cellular distribution of SNAP‐25 and the diversity of the toxin's neuronal acceptors are being exploited for other therapeutic applications. 相似文献
28.
目的:研究开He患者的舌位置有无特征性变异。方法:利用舌背碘油造影方法,增加头颅侧位定位X线片上舌背的显影效果,在头颅侧位定位X线片上以舌体在固有口腔内的相对位置确定舌体的位置,通过开He与正常He者知位置的团体t检验比较,找出开He患者的舌位置变异特性。结果:开He患者与正常He者比较,舌根部与悬雍垂之间的间隙增大,舌背部与腭表面之间的间隙减小,舌尖部更靠近牙齿,结论:开He个体相对于正常He个体舌位置有向前,向上的变化特点,这可能是开He的病因之一。 相似文献
29.
R. K. Vesalainen K. U. O. Tahvanainen T. J. Kaila I. M. Kantola T. A. Kuusela D. L. Eckberg 《Clinical physiology and functional imaging》1997,17(2):135-133
We studied how posture influences the effects of transdermal scopolamine on autonomic cardiovascular regulation in a randomized, double-blind, placebo-controlled crossover study of 10 healthy young volunteers. We recorded the electrocardiogram and auscultatory sphygmomanometric and continuous non-invasive finger arterial pressure (Finapres device) to obtain signals for the beat-by-beat R–R interval and systolic, mean and diastolic pressures. R–R interval and arterial pressure variabilities were characterized by power spectral analysis. Scopolamine increased the mean R–R intervals and reduced arterial pressure in both the supine and the standing positions, but did not affect blood pressure variability. Scopolamine increased the total variability of R–R interval and its mid- (0·07–0·15 Hz) and high- (0·15–0·40 Hz) frequency band power in the standing position during controlled breathing at 0·25 Hz. In the supine position, scopolamine did not affect R–R interval variability. In the deep breathing test, scopolamine increased the maximal expiratory–inspiratory R–R interval ratio. This study showed that low-dose scopolamine increases vagal cardiac inhibition in both supine and standing positions in healthy volunteers. However, scopolamine increases heart rate variability only in the standing position during partial vagal withdrawal. The study also demonstrates that transdermal scopolamine decreases blood pressure in healthy young subjects. 相似文献
30.
Reiner Mengel Matthias Eigenbrodt Thomas Schünemann Lavin Florès-de-Jacoby 《Journal of clinical periodontology》1996,23(5):437-443
Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists. 相似文献