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排序方式: 共有1224条查询结果,搜索用时 125 毫秒
11.
Hoffmann M Gaikwad J Schmalz G Cavender A D'Souza R 《Connective tissue research》2002,43(2-3):376-380
Studying the mechanisms of molecular interactions in developing tissues demands sensitive molecular biological in vivo and in vitro techniques. Laser capture microdissection (LCM) allows for the isolation of mRNA in histological sections even from single cells, thus enabling the identification of in vivo gene expression products in closely circumscribed tissue areas. The aims of this study were to assess the optimal fixation, processing, and staining conditions to retrieve RNA from microdissected odontoblasts. Fluorometric assays and RT-PCR analysis of alpha 1(I) collagen, dentin sialophosphoprotein (Dspp), and osteocalcin (OC) confirmed that the total RNA isolated from day 0 and day 3 captured odontoblasts was sufficient in quantity and quality. Our results indicate that individual odontoblasts obtained by LCM are morphologically intact and chemically unaltered, allowing accurate molecular and biochemical analyses. 相似文献
12.
Kenneth A. Perkins Leonard H. Epstein Richard L. Stiller Madelyn H. Fernstrom Joan E. Sexton Rolf G. Jacob Rena Solberg 《Psychopharmacology》1991,103(1):103-109
The inverse relationship between smoking and body weight may be due in part to nicotine's effects on reducing hunger and eating. Male smokers and nonsmokers (n=10 each), abstinent overnight from smoking and food, participated in four sessions, involving consumption of a liquid caloric load or water followed by nicotine (15 µg/kg) or placebo via nasal spray every 20 min for 2 h. Hunger and satiety (fullness) ratings were obtained prior to each dose presentation. At the end of the two sessions involving the caloric load (simulating breakfast), subjects were also presented with typical lunch/snack food items varying in sweet taste and fat content for ad lib consumption. Results indicated that, for both smokers and nonsmokers, the hunger-reducing effects of nicotine occurred only following caloric load consumption, and there was no effect of nicotine on hunger after water consumption. Smokers unexpectedly reported greater satiation than nonsmokers following the caloric load regardless of nicotine or placebo condition. Nicotine also resulted in less caloric intake during the meal, and the decrease was not specific to consumption of sweet, high-fat foods. These results indicate that nicotine reduces appetite, possibly helping to explain the influence of smoking on body weight. 相似文献
13.
目的研究人工栽培盐生肉苁蓉(寄主为囊果碱蓬)中的苯乙醇苷类化学成分。方法采用色谱技术分离纯化,根据理化性质和谱学数据鉴定其结构。结果从盐生肉苁蓉栽培品中分离得到7个苯乙醇苷类化合物,分别鉴定为松果菊苷(echinacoside,1)、肉苁蓉苷A(cistanosideA,2)、毛蕊花苷(acteoside,3)、异毛蕊花苷(isoacteoside,4)、2′乙酰基毛蕊花苷(2′acetylacteoside,5)、管花苷B(tubulosideB,6)、1O[2(4羟基苯基)乙基]6O(E)香豆酰基βD吡喃葡萄糖苷(EutigosideA,7)。结论首次对人工栽培盐生肉苁蓉的化学成分进行了研究,分离得到7个化合物,其中化合物7为首次从列当科植物中分得,化合物1-6为在该种植物栽培品中首次报道。 相似文献
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Rena Nakayama Chiharu Matsuda Yuki Nakayama Chiyoko Hakuta Masahiko Shimada 《Acta odontologica Scandinavica》2018,76(4):294-298
Objective: To assess the intraoral conditions and oral function of patients with amyotrophic lateral sclerosis (ALS).Material and methods: This single-centre, cross-sectional observational study included 50 ALS patients, who were treated with tracheostomy positive-pressure ventilation (TPPV) while hospitalized. The disease duration, TPPV duration, current number of teeth, number of occlusal units, number of decayed/missing/filled teeth, community periodontal index, bleeding on probing, dental calculus, maximum mouth opening, salivation rate, tongue anomalies (atrophy or hypertrophy) and tongue coating were determined for each patient. Differences in intraoral conditions according to disease duration or TPPV duration were statistically analysed.Results: The maximum mouth opening was low in the included patients, with a mean distance of 13.7?±?7.4?mm. Furthermore, the maximum mouth opening showed a significant negative correlation with both disease duration and TPPV duration. No statistically significant differences were found between any other intraoral parameters and disease duration or TPPV duration.Conclusions: Severe dental disease is uncommon among hospitalized ALS patients who receive oral care by nurses; however, mouth opening is very restricted in these patients. Early intervention for restricted mouth opening, directed by a dentist or dental hygienist, is essential in this population. 相似文献
16.
Hypophosphatasia (HPP) is an inherited skeletal disease with features of hypomineralization of bone and early exfoliation of primary teeth due to disturbed cementum formation. Recent introduction of enzyme replacement therapy has reduced mortality in severe cases, though the effects of that treatment on dental manifestations remain unknown. We examined an avulsed primary incisor in a 3-year-old female diagnosed with perinatal HPP who underwent enzyme replacement therapy from 1 day after birth and report our findings. 相似文献
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Arifah Chieko Ardin Kazuhiko Nakano Aki Yamana Rena Okawa Shuhei Naka Michiyo Matsumoto Takashi Ooshima 《Pediatric Dental Journal》2011,21(1):56-62
Developments in molecular biological techniques enables rapid and easy identification of periodontopathic bacterial species in clinical specimens. However, there are few reports regarding their application for community dentistry. The aim of this study was to show successful application of a molecular biological technique for evaluation of changes in periodontal bacterial species in children at daycare centers. We studied 187 children who received oral examinations in 2009 and 186 who received examinations in 2010, among whom 102 were examined in both years. Clinical parameters regarding periodontal conditions were evaluated and the distribution of 10 periodontopathic species in dental plaque specimens were determined by polymerase chain reaction. Periodontal pocket depth values in the 2010 group were significantly smaller than those in 2009. When the subjects were divided into those with (positive group) and without (negative group) Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, or Campylobacter rectus in 2009, the positive group had significantly smaller periodontal pocket values than the negative group. In addition, the rate of subjects with P. gingivalis, T. denticola, T. forsythia, or C. rectus in the positive group in 2010 was significantly reduced. Our findings demonstrate that molecular biological methods provide more information as compared to a standard clinical examination when evaluating changes of periodontal conditions in the field of community dentistry. 相似文献
19.
Estimating sleep from multisensory armband measurements: validity and reliability in teens 下载免费PDF全文
Brandy M. Roane Eliza Van Reen Chantelle N. Hart Rena Wing Mary A. Carskadon 《Journal of sleep research》2015,24(6):714-721
Given the recognition that sleep may influence obesity risk, there is increasing interest in measuring sleep parameters within obesity studies. The goal of the current analyses was to determine whether the SenseWear® Pro3 Armband (armband), typically used to assess physical activity, is reliable at assessing sleep parameters. The armband was compared with the AMI Motionlogger® (actigraph), a validated activity monitor for sleep assessment, and with polysomnography, the gold standard for assessing sleep. Participants were 20 adolescents (mean age = 15.5 years) with a mean body mass index percentile of 63.7. All participants wore the armband and actigraph on their non‐dominant arm while in‐lab during a nocturnal polysomnographic recording (600 min). Epoch‐by‐epoch sleep/wake data and concordance of sleep parameters were examined. No significant sleep parameter differences were found between the armband and polysomnography; the actigraph tended to overestimate sleep and underestimate wake compared with polysomnography. Both devices showed high sleep sensitivity, but lower wake detection rates. Bland–Altman plots showed large individual differences in armband sleep parameter concordance rates. The armband did well estimating sleep overall, with group results more similar to polysomnography than the actigraph; however, the armband was less accurate at an individual level than the actigraph. 相似文献
20.
Characterization of cleaning and disinfecting tasks and product use among hospital occupations 下载免费PDF全文