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排序方式: 共有1260条查询结果,搜索用时 31 毫秒
1.
Robert Willer Farinazzo Vitral Carlos de Souza Telles Marcelo Reis Fraga Roberto Sotto Maior Fortes de Oliveira Orlando Motohiro Tanaka 《American journal of orthodontics and dentofacial orthopedics》2004,126(1):48-52
Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed. 相似文献
2.
Jose Carlos de Fraga João Pippi Salle Mauro Boher Carlos R. Antunes 《Pediatric surgery international》1995,10(5-6):376-378
Laryngotracheoesophageal cleft is an uncommon disease that is difficult to diagnose and treat. Repair of the cleft depends on length and localization of the defect as well as the associated anomalies. A successful repair of a type II cleft is reported in this paper. An anterior split of the larynx and trachea was used and provided excellent exposure and safe repair without injury to the neurovascular structures. This is the best approach and should be used to correct all type II defects. 相似文献
3.
AIMS: The present study aimed to evaluate the relationship between intestinal inflammation, interferon-gamma (IFN-gamma) levels and intestinal levels of dopamine, its precursor l-3,4-dihydroxyphenylalanine (L-DOPA), and the activity of aromatic L-amino acid decarboxylase (AADC) activity along the digestive tract in a rat experimental model of colitis. METHODS: Colitis was induced by rectal administration of 2,4,6-trinitrobenzene sulphonic acid (TNBS). Catechol derivatives were assayed by means of HPLC-EC. RESULTS: It is shown that dopamine and noradrenaline levels in the distal colon (inflamed mucosa), but not in the ileum (non-inflamed mucosa), of TNBS-treated rats were markedly lower than in control animals. A slight decrease in L-DOPA tissue levels, no changes in AADC activity and an increase in plasma IFN-gamma levels accompanied this decrease in dopamine levels. Exposure of Caco-2 cells, a human intestinal epithelial cell line, to human IFN-gamma resulted in a concentration-dependent and long-lasting inhibition of L-DOPA uptake, which most likely explains the decrease in dopamine levels in the inflamed mucosa. CONCLUSION: Changes in tissue levels of noradrenaline and dopamine in experimental colitis in the rat follow a similar pattern to that observed in patients with Crohn's disease and ulcerative colitis. In this model of experimental colitis, the decrease in dopamine levels is most likely explained by the inhibitory effect of IFN-gamma on L-DOPA uptake by intestinal epithelial cells. 相似文献
4.
R. Gallego T. García-Caballero A. Beiras M. Fraga J. Forteza 《Virchows Archiv : an international journal of pathology》1995,426(3):317-321
We have analysed the expression of the neural cell adhesion molecule (NCAM) in normal Merkel cells of pig and human skin, and in nine neuroendocrine carcinomas of the skin (Merkel cell carcinomas). NCAM immunoreactivity was observed in virtually all Merkel cells, both in epidermis and vibrissae of pig snout skin and in human epidermis. Immunostaining surrounded the entire surface of Merkel cells and was not restricted to the contact areas between Merkel cells and nerve terminals. All Merkel cell carcinomas studied were also positive for NCAM. The immunostaining pattern of the tumour cells was similar to that observed in normal Merkel cells; the immunoreactivity was confined to the cell membranes. These results suggest that NCAM may be used as an immunohistochemical marker for both Merkel cells and Merkel cell tumours. 相似文献
5.
6.
Marta Tojo Raquel Perez-Becerra Angel Vazquez-Boquete Arancha García-Rivero Tomas García-Caballero Jeronimo Forteza Maximo Fraga 《Diagnostic molecular pathology》2008,17(1):59-63
Fluorescence in situ hybridization (FISH) is a useful cytogenetic technique for the detection of chromosome aberrations. However, applying this technique routinely on paraffin-embedded tissue is hampered by technical problems. The efficiency of hybridization is influenced by formalin fixation time, and this may vary considerably between specimens. We present a simple method for improving hybridization by microscopically monitoring the time of enzymatic digestion. To establish optimal digestion time, enzymatic digestion was stopped at 3-minute intervals for biopsies and 10-minute intervals for autopsies in 24 paraffin-embedded samples. At every stop, tissue morphology was examined under light microscopy to determine if observed changes could be correlated with subsequent FISH results. The appearance of fernlike formations was found to mark the optimal digestion time that produced the strongest hybridization signals. Using this method of digestion time control, an additional 41 cases were evaluated for FISH with various types of probe. Monitoring under the microscope could be more spaced if the morphology did not change after the first visual control and could be adapted to the type of sample (in general, endoscopic samples, total digestion time of about 10 min; routine biopsies, 15 to 30 min; autopsy samples, 20 to 40 min). In every case, the appearance of the fernlike pattern correlated with proper hybridization signal. Monitoring digestion time for the appearance of fernlike structures is a useful method for improving reproducibility of FISH technique on paraffin-embedded samples. It is particularly useful when dealing with samples under heterogeneous fixation conditions (consultations, autopsies, etc.), because it eliminates the need for repetition. 相似文献
7.
Jan Höltge Linda Theron Richard G. Cowden Kaymarlin Govender Sally I. Maximo Jennifer S. Carranza Bhumika Kapoor Aakanksha Tomar Angelique van Rensburg Shuang Lu Hongwei Hu Valeria Cavioni Alessia Agliati Ilaria Grazzani Yoel Smedema Gunjanpreet Kaur Kingsley G. Hurlington Jackie Sanders Michael Ungar 《The Journal of adolescent health》2021,68(3):580-588
PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources. 相似文献
8.
Rodiño S Rama P Pensado A Dávila ML Molins N Fraga M 《Revista espa?ola de anestesiología y reanimación》1999,46(10):427-432
OBJECTIVE: To compare the recovery of patients after anesthesia with sevoflurane or propofol during open urological surgery or lumbar column surgery of intermediate duration. PATIENTS AND METHODS: Thirty-six ASA I, II or II patients were enrolled prospectively and randomly assigned to two groups to receive either sevoflurane (n = 19) or proporol (n = 17). Anesthetic induction was accomplished with thiopental, fentanil and vecuronium. During anesthetic maintenance a mixture of 60% nitrous oxide in oxygen plus the drug under study was adjusted to keep blood pressure and/or heart rate within +/- 20% of baseline. After surgery we recorded time until eye opening, spontaneous breathing, extubation, orientation, and identification of parts of the body. Side effects were likewise recorded. In the postanesthetic recovery ward patient condition was assessed using the Aldrete scale, the Newman-Trieger test and a visual analog scale for postoperative pain. Consumption of analgesic during the first 24 h after surgery was monitored. RESULTS: No significant differences were found in demographic data; duration of anesthesia; anesthetic doses; or time until spontaneous breathing, extubation, orientation or identification of parts of the body. Only time until eye opening was shorter in the sevoflurane group than in the propofol group (6.9 +/- 3.3 vs 11.5 +/- 4.8 min; p < 0.05). No differences were recorded on scales reflecting intermediate-term recovery. Analgesic consumption and the incidence of side effects were similar in both groups. CONCLUSIONS: Sevoflurane and propofol are comparable for anesthetic maintenance in urological and neurological procedures of intermediate duration. 相似文献
9.
Starnes SL Duncan BW Kneebone JM Fraga CH States S Rosenthal GL Lupinetti FM 《The Journal of thoracic and cardiovascular surgery》2000,120(5):902-907
OBJECTIVE: Pulmonary arteriovenous malformations cause progressive cyanosis in children after cavopulmonary anastomosis and may be due to abnormal angiogenesis. We determined the microvessel density, a marker of angiogenesis, in the lungs of children after cavopulmonary anastomosis. METHODS: Lung biopsy specimens were obtained from 8 children after cavopulmonary anastomosis and from 4 control patients. Three of the 8 children undergoing cavopulmonary anastomosis had clinical and angiographic evidence of pulmonary arteriovenous malformations, whereas the other 5 were free of symptoms. Routine histologic and immunohistologic stains were performed with a primary antibody to von Willebrand factor. Microvessel staining for von Willebrand factor was determined for 10 fields (200x) per patient. RESULTS: Patients with and without pulmonary arteriovenous malformations after cavopulmonary anastomosis demonstrated significantly increased microvessel density compared with control subjects (32.7 +/- 2.8 vs 9.3 +/- 4.6, P =.02, and 31.5 +/- 15.7 vs 9.3 +/- 4.6, P =.01, respectively). There was no difference in microvessel density in children with and without clinically apparent pulmonary arteriovenous malformations after cavopulmonary anastomosis (P =.9). The children with pulmonary arteriovenous malformations had numerous greatly dilated vessels that were absent in the asymptomatic children after cavopulmonary anastomosis. CONCLUSIONS: After cavopulmonary anastomosis, pulmonary microvessel density is increased even in the absence of clinically apparent pulmonary arteriovenous malformations, supporting the presence of a constant angiogenic stimulus. Children with clinically apparent pulmonary arteriovenous malformations possess large numbers of greatly dilated pulmonary microvessels, which are absent in asymptomatic children after cavopulmonary anastomosis. These results suggest that the transition to clinically apparent pulmonary arteriovenous malformations may be due to mechanisms that lead to vessel dilation and remodeling. 相似文献
10.
Carolina de Mattos Duarte Hugo Verli Joo Xavier de Araújo-Júnior Isac Almeida de Medeiros Eliezer J. Barreiro Carlos Alberto Manssour Fraga 《European journal of pharmaceutical sciences》2004,23(4-5):363-369
We describe herein the structural optimization of new piperamide analogues, designed from two natural prototypes, piperine 1 and piperdardine 2, obtained from Piper tuberculatum Jacq. (Piperaceae). Molecular modeling studies using semiempirical AM1 method were made in order to establish rational modifications to optimize them by molecular simplification. The targeted compounds (10) and (11) were respectively obtained using benzaldehyde (12) and para-anisaldehyde (13) as starting materials. 1H NMR spectra showed that the target compounds were diastereoselectively obtained as the (E)-isomer, the same geometry of the natural prototypes. These new synthetic amides presented significant hypotensive effects in cardiovascular essays using in vivo methodologies. Compound 11 (N-[5-(4′-methoxyphenyl)-2(E)-pentenoyl]thiomorpholine) showed a potency 10,000 times greater than its prototype 5, evidencing an optimization of the molecular architecture for this class of hypotensive drug candidates. 相似文献