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101.
Catecholamine contents and activities of catecholamine synthesizing and inactivating enzymes in the salivary glands of young growing rats 总被引:1,自引:0,他引:1
The catecholamine concentrations and activities of tyrosine hydroxylase, DOPA decarboxylase, dopamine β-hydroxylase, catechol 0-methyltransferase and monoamine oxidase in the submandibular and sublingual glands of developing rats ranging in age from 1 to 70 days were measured. The total concentration of catecholamines and the total activities of tyrosine hydroxylase and monoamine oxidase increased markedly up to 56 days and then remained at about the same levels. The total activities of dopamine β-hydroxylase increased steadily between 1 and 70 days of age. The total activity of DOPA decarboxylase increased rapidly to approximately 55-fold up to 21 days of age, thereafter decreasing markedly and at 70 days of age was only 2.6-fold higher than that at 1 day of age, probably because endogenous inhibitors are present in the submandibular gland of rats older than 42-days. The total activity of catechol 0-methyltransferase increased 38-fold up to 56 days of age, and thereafter decreased. Catecholamine concentrations and activities of the enzymes per unit weight reached maximal levels at the age of 14 or 21 days except for catechol 0-methyltransferase which reached maximal activity at 42 days of age. After 14 days, the catecholamine concentrations remained at almost the same level. The activity of dopamine β-hydroxylase and catechol 0-methyltransferase increased 2–3-fold reaching maxima at 21 and 28 days respectively. The monoamine oxidase activity remained at about the same level after birth. 相似文献
102.
103.
Mariko Takashima Noriyuki Kitai Shumei Murakami Souhei Furukawa Sven Kreiborg Kenji Takada 《The Cleft palate-craniofacial journal》2003,40(1):6-12
OBJECTIVE: To test the following hypotheses in hemifacial microsomia (HFM): (1) the volumes of the masseter, lateral and medial pterygoid, and temporal muscles are reduced on the affected versus unaffected side; (2) significant differences exist between the degrees of right-left disproportion in these four masticatory muscles; (3) circumferential shapes of the masticatory muscles are more irregular on the affected versus unaffected side; and (4) the degree of masticatory muscle right-left disproportion can be judged by the degree of ear, mandibular, or dental anomalies. SUBJECTS AND METHODS: Ten preadolescent patients with HFM were studied using facial photographs, dental casts, cephalometric and panoramic radiographs, and helical computed tomography scanning and three-dimensional reconstruction technique. Volumes of masseter, lateral and medial pterygoid, and temporal muscles on both sides were measured. Muscle volume disproportion was expressed as the affected/unaffected ratio. Muscle circumferential irregularity was expressed as the ratio between the total circumferential length and corresponding cross-sectional area. RESULTS: Masticatory muscle volumes were significantly smaller on the affected versus unaffected side. No significant differences were observed between the degrees of disproportion of the four masticatory muscles examined. Circumferential shapes of masticatory muscles were significantly more irregular on the affected versus unaffected side. There were no significant relationships of the degree of ear, mandibular, or dental anomalies in relation to masticatory muscle disproportion. CONCLUSIONS: In HFM the masseter, lateral and medial pterygoid, and temporal muscles all have a significantly smaller volume on the affected versus unaffected side, and specific muscles were not severely affected in the present subjects. Furthermore, all four muscles showed a significantly more irregular shape on the affected versus unaffected side. Finally, the severity of masticatory muscle disproportion can probably not be judged by the degree of ear, mandibular, and dental anomalies in preadolescent patients with HFM. 相似文献
104.
A mini-implant for orthodontic anchorage in a deep overbite case 总被引:4,自引:0,他引:4
This article describes the orthodontic treatment of a 19-year-old female patient with anterior crowding. There was a moderate arch length discrepancy in the lower dental arch, a significant deep overbite, and a "gummy smile." We inserted an orthodontic mini-implant as anchorage for the intrusion of the upper incisor segment, followed by alignment of the upper and lower dental arches with an edgewise appliance without tooth extraction. The overbite was corrected from +7.2 mm to +1.7 mm by upper incisor intrusion, and the gummy smile was improved. Good occlusion and facial esthetics were achieved, and these results have been maintained for two years after completion of the active treatment. 相似文献
105.
A sensitive enzymatic method (SK-013) for detection and quantification of specific periodontopathogens 总被引:4,自引:0,他引:4
Kazuyuki Ishihara Yuko Naito Tetsuo Kato Ichiro Takazoe Katsuji Okuda Toru Eguchi Koichi Nakashima Naoki Matsuda Kyoko Yamasaki Kenji Hasegawa Hirohisa Suido Kunio Sugihara 《Journal of periodontal research》1992,27(2):81-85
Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola have been found to predominate in periodontal pockets of patients with adult periodontitis. These microorganisms hydrolyze the synthetic peptide N-benzoyl-DL-arginine-2-naphthylamide (BANA). In this study, we developed an enzymatic method, designated SK-013, to detect the existence of these microorganisms in subgingival plaque bacteria. This enzymatic method was based on the observation of the hydrolysis of N-carbobenzoxy-glycyl-glycyl-arginyl-3,5-dibromo-4-hydroxyaniline (N-CBz-Gly-Gly-Arg-DBHA) and made more sensitive by adding an enhancing system. The SK-013 was specifically positive for P. gingivalis, B. forsythus, T. denticola, and some strains of Capnocytophaga species, but was not specific for any of the other bacterial strains tested. This SK-013 system may be valuable for detection and quantification of periodontal disease-associated bacteria in subgingival plaque and thus for diagnosis of periodontal infections. 相似文献
106.
K Hashimoto N Mase K Iwai K Shinoda E Sairenji 《Oral surgery, oral medicine, and oral pathology》1991,72(1):126-132
A desmoplastic fibroma of the maxillary sinus is reported in a 15-year-old boy. Desmoplastic fibroma is a rare benign tumor in the maxillofacial region. The features of this case and of 49 previously described lesions are analyzed and discussed. 相似文献
107.
Uehara J Kuboki T Fujisawa T Kojima S Maekawa K Yatani H 《Archives of oral biology》2004,49(2):133-142
The objective of this study was to detect soluble-form tumour necrosis factor receptors (sTNFRs) in temporomandibular joint (TMJ) synovial fluid aspirates, and to compare the sTNFR concentrations between painful anterior disc displacement without reduction and osteoarthritis (ADDwoR/OA) and asymptomatic TMJs.Synovial fluid was sampled from the superior TMJ cavity of 11 painful ADDwoR/OA cases (mean age: 36.9 years) and 10 asymptomatic females (mean age: 24.7 years) by diluted aspiration. The concentrations of sTNFR-I and -II in the synovial fluid were measured using human sTNFR-I and -II enzyme-linked immunosorbent assays. The total protein concentrations in synovial fluids were measured using a bicinchoninic acid protein assay kit. All data were normalised to the total protein concentration of each sample.Two-way factorial analysis of variance and post hoc multiple comparison revealed that: (1). mean normalised sTNFR-I and -II concentrations were higher in TMJ synovial aspirates from ADDwoR/OA patients than from healthy controls; (2). in the ADDwoR/OA patients and the healthy controls, the sTNFR-I concentration in TMJ synovial aspirates was higher than the sTNFR-II concentration; and (3). high TMJ synovial aspirate sTNFR-II seemed to be associated with less TMJ pain and a less restricted range of mouth opening in the ADDwoR/OA patients.The concentrations of sTNFRs in TMJ synovial fluid are higher in the presence of painful ADDwoR/OA, which could modulate intracapsular inflammation. 相似文献
108.
OBJECTIVE: To investigate the laterality of the normal asymmetry of the human face, examining differences in laterality in relation to sex, growth stage, and skeletal classification. MATERIALS AND METHODS: A total of 1800 Japanese subjects (651 males and 1149 females; mean age, 15 years 3 months; range, 4 years 2 months to 59 years 11 months) were selected. Individuals in the sample were categorized according to sex, one of three growth stages, and one of three skeletal patterns. Differences in length between distances from the points at which ear rods were inserted to the facial midline and the perpendicular distance from the soft-tissue menton to the facial midline were measured on a frontal facial photograph. Subjects with a discrepancy of more than 3 standard deviations of the measurement error were categorized as having left- or right-sided laterality. RESULTS: Of subjects with facial asymmetry, 79.7% had a wider right hemiface, and 79.3% of those with chin deviation had left-sided laterality. These tendencies were independent of sex, age, or skeletal jaw relationships. In this regard, during pubertal growth, the proportion of subjects with wider right hemiface decreased (P < .0001), whereas the proportion of those with a wider left hemiface increased (P < .01), despite a consistent tendency for right-sided dominance. CONCLUSION: These results suggest that laterality in the normal asymmetry of the face, which is consistently found in humans, is likely to be a hereditary rather than an acquired trait. 相似文献
109.
Hashimoto M Ito S Tay FR Svizero NR Sano H Kaga M Pashley DH 《Journal of dental research》2004,83(11):843-848
This study evaluated the extent of water penetration through resin-dentin interfaces before and after being sealed with adhesives. Four adhesive resin systems (2 total-etch adhesives and 2 self-etching primer adhesives) were used in this study. Dentin disks were placed in a split-chamber device, and in situ fluid movement across dentin was measured, with and without physiological pressure, during bonding procedures or 24 hrs after bonding. The fluid movement across dentin occurs via dentin tubules after acid-etching. Large outward or inward fluid shifts across dentin were observed during air-drying and light-curing for resin application. The amount of fluid movement across resin-bonded dentin when total-etch adhesives were used was significantly greater than that with self-etching adhesives. The milder acid-etching effects of self-etching primers may retain hybridized smear plugs within the tubules that reduce outward fluid flow, resulting in superior dentin sealing. 相似文献
110.
Abe S Kaneko H Nakamura Y Watanabe Y Shintani M Hashimoto M Yamane G Ide Y Shimono M Ishikawa T Yamada Y Hayashi T 《The Bulletin of Tokyo Dental College》2002,43(3):199-203
It has been reported that swallowing is a rhythmic movement, in which the onset of the oro-pharyngeal stage of swallowing starts from the mylohyoid muscle, followed by movement of the oral and pharyngeal muscles, and reaching the superior esophageal sphincter muscle. This is defined as the oro-pharyngeal stage of swallowing. It has also been reported that along with this movement, the larynx elevates in an antero-superior direction. To investigate the swallowing movement, it would be useful to be able to detect the start of swallowing movements from the body surface. Such a device was designed in this study to investigate the relationships between the onset of laryngeal movement and the EMG initiation of the anterior digastric muscle. Although experimental conditions must be further examined, we were able to record the reproducible movement and the position of larynx using our device provides another tool for studying the swallowing movement. 相似文献