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排序方式: 共有2213条查询结果,搜索用时 0 毫秒
1.
Lily Shum A B M Rabie Urban H?gg 《American journal of orthodontics and dentofacial orthopedics》2004,125(2):185-190
This study assessed the amount of vascular endothelial growth factor (VEGF) expression and related the findings to new bone formation in the posterior glenoid fossa during stepwise mandibular advancement. A total of 250 female Sprague-Dawley rats, 35 days old, were randomly divided into 10 groups, each including 5 control and 20 experimental rats. Within each group, 10 experimental rats were fitted with functional appliances with a 1-step advancement of 3.5 mm. Another 10 were fitted with stepwise appliances with an initial advancement of 2 mm and a subsequent increase to 3.5 mm on day 30. The rats in the experimental groups were killed on days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, respectively. The matched controls were killed on the same time points. Sections (7 microm) were cut through the glenoid fossa sagittally and stained with anti-VEGF antibody. VEGF expression in the posterior glenoid fossa was evaluated with a computer-assisted image-analyzing system. Both VEGF expression and new bone formation were greater in the experimental rats than in the controls. During stepwise advancement, initial VEGF expression was less than that of 1-step advancement, but the second advancement elicited another peak on day 44. New bone formation was also less than that of 1-step advancement during early stages of stepwise advancement but then began to increase from day 37 onward. The maximum increase was observed on day 60. Stepwise advancement of the mandible delivers mechanical stimuli that produce a series of tissue responses that lead to increased vascularization and bone formation. 相似文献
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3.
Rachelle Bouffard Lily Hechtman Klaus Minde Fiorella Iaboni-Kassab 《Revue canadienne de psychiatrie》2003,48(8):546-554
OBJECTIVE: To evaluate the efficacy of methylphenidate in treating adults with attention-deficit hyperactivity disorder (ADHD), using subjective (self-report) and objective (computerized test) measures. METHOD: This double-blind crossover trial of placebo vs methylphenidate included subjects with childhood and current ADHD symptoms, IQs above 80, no other psychiatric condition explaining their difficulties or requiring other treatment, and no substance abuse in the previous 6 months. We administered 10 mg 3 times daily of medication (that is, placebo or methylphenidate) for 2 weeks. On the final day, subjects completed self-report measures and were tested on computerized tests. We then increased dosage to 15 mg 3 times daily for 2 weeks and administered a complete reassessment on the final day. Following a 1-week washout, we repeated this process on the second medication (that is, placebo or methylphenidate). RESULTS: Thirty adults with ADHD participated. Self-report measures and computerized tests showed significant improvements in ADHD symptoms on methylphenidate, compared with placebo. Other psychiatric symptoms (notably, anxiety and depression) were alleviated with methylphenidate. There was no significant difference between the 2 dosages of methylphenidate. CONCLUSION: Methylphenidate is effective in improving ADHD symptoms in adults with ADHD, is well tolerated, and has minimal side effects. 相似文献
4.
H. A. Tillmann Hein MD C. Tracy Suit MD Linda K. Douning MD Samuel P. Marynick MD J. Michael Putman MD Lily Zhang PhD Michael A.E. Ramsey MD 《Journal of clinical anesthesia》1997,9(8):617
This study retrospectively compares patients who underwent outpatient transvaginal follicle aspiration with either a propofol- or methohexital-based intravenous sedation technique. Data collected from patient charts (n = 212) over a 46-month period were analyzed to determine the effects of each sedation technique on procedure and recovery times, number of retrieved ova, as well as rates of nausea, fertilization, cleavage, pregnancy, and delivery. All patients were included in the study, regardless of age or diagnosis. procedure time was lower in the propofol group (51 t 18 min) than in the methohexital group (61 I 20 min) (p > 0.01). Patients in the methohexital group (139 2 51 min) spent more time in the recovery room than did those in the propofol group (71 ? 34 min) (p > 0.01). The nausea rates were significantly lower in the propofol group compared with the methohexital group (1.9% vs. 14.4%, respectively) (p > 0.02). Fertilization rate in the propofol group was 77.7% and was 62.9% in the methohexital group (p > 0.01). The numbers of retrieved ova and the cleavage rates were similar in both groups. The rate of pregnancy in patients sedated with propofol (46.1%) was higher than the methohexital group (26.9%) (p > 0.02). Delivery rate was 38.5% in the propofol group and 20.6% in the methohexital group (p > 0.02). In summary, propofol intravenous sedation for transvaginal follicle aspiration was associ- ated with an improved outcome. Pregnancy and delivery rates were higher while nausea, an unpleasant side effect, was sharply reduced. 相似文献
5.
MIM/BEG4, a Sonic hedgehog-responsive gene that potentiates Gli-dependent transcription 总被引:7,自引:0,他引:7
Callahan CA Ofstad T Horng L Wang JK Zhen HH Coulombe PA Oro AE 《Genes & development》2004,18(22):2724-2729
6.
Owens EB Hinshaw SP Kraemer HC Arnold LE Abikoff HB Cantwell DP Conners CK Elliott G Greenhill LL Hechtman L Hoza B Jensen PS March JS Newcorn JH Pelham WE Severe JB Swanson JM Vitiello B Wells KC Wigal T 《Journal of consulting and clinical psychology》2003,71(3):540-552
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. 相似文献
7.
Takada D Emi M Ezura Y Nobe Y Kawamura K Iino Y Katayama Y Xin Y Wu LL Larringa-Shum S Stephenson SH Hunt SC Hopkins PN 《Journal of human genetics》2002,47(12):0656-0664
8.
Marruchella G Di Leonardo M Di Guardo G Romanucci M Marà M G Tiscar P Mosca F Della Salda L 《Journal of comparative pathology》2004,131(1):10-17
Heat shock proteins (HSPs), known to play a key role in cellular homeostasis, may also play a role in the defensive mechanisms of gastric mucosa. By means of appropriate immunohistochemical and immunobiochemical techniques, the expression of HSP27, HSP72 and HSP73 within the epithelium of normal and pre-ulcerative (hyperkeratinized) mucosa of the pars oesophagea of abattoir pigs was assessed. In normal mucosa, HSP72 and HSP73 expression was mainly limited to the basal epithelial cell layer, whereas HSP27 expression was consistently detected within the superficial epithelial cell layers. In hyperkeratinized mucosa, HSP72 and HSP73 immunoreactivity appeared to be more widespread, becoming very intense within epithelial cells affected by hydropic degeneration. Hyperkeratinized mucosa also showed HSP27 immunoreactivity, which was particularly intense in epithelial areas affected by hydropic degeneration. Western blot analysis confirmed HSP27, HSP72 and HSP73 expression in normal and in pre-ulcerative mucosa of the pars oesophagea. Semi-quantitative analysis showed that for all three HSPs the immunoreactivity was more intense in pre-ulcerative mucosa than in normal mucosa. The different expression patterns observed may have functional significance; further studies are needed, however, to define the role of HSPs in swine oesophagogastric lesions, the aetiology and pathogenesis of which are largely unknown. 相似文献
9.
The cannabinoid system and immune modulation 总被引:13,自引:0,他引:13
Klein TW Newton C Larsen K Lu L Perkins I Nong L Friedman H 《Journal of leukocyte biology》2003,74(4):486-496
10.
Introduction of new clones of penicillin-nonsusceptible Streptococcus pneumoniae in Hong Kong 下载免费PDF全文
Analysis of penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) isolates in Hong Kong by use of a combination of antibiogram typing, serotyping, multilocus sequence typing, and pulsed-field gel electrophoresis indicated that the dissemination of PNSP was the result of the spread of international clones: variants of the Spain(23F)-1 or Spain(6B)-2 clones were the predominant PNSP isolates from 1994 to 1997 and remained so, but Taiwan(19F)-14 and Taiwan serotype 6B clones were disseminated in Hong Kong in 1999 and 2000. Concomitant changes in antibiotic susceptibility profiles, with the rate of susceptibility to chloramphenicol rising from 10% in the period from 1994 to 1997 to 31% (P < 0.001) in 1999 and 2000, were noted to accompany the shift of clones. 相似文献