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51.
Periodontal changes in patients undergoing radiotherapy 总被引:1,自引:0,他引:1
BACKGROUND: The purpose of this study was to evaluate changes in the periodontium in patients who received head and neck radiation therapy. METHODS: Periodontal clinical parameters (probing depth, clinical attachment level, gingival recession, plaque index, and bleeding on probing) were assessed on 27 patients before and 6 to 8 months following radiation therapy in the head and neck area. RESULTS: The greatest changes occurred in clinical attachment level: overall, 70.3% of the patients showed a loss, with 92% evincing loss in the mandible. Attachment loss was directly related to the field of radiation and was greater when the jaws were actually included in the irradiated area. CONCLUSION: Periodontal status should be evaluated prior to and following radiation therapy in the oral-maxillary-facial region to help ensure that periodontal health is maintained in oncology patients. 相似文献
52.
Dental prostheses are frequently used to avoid psychologic, speech, or swallowing problems in preschool children with considerable tooth loss. Two cases of preschool children are presented, involving multiple loss of primary teeth. The purpose of this study was to promote the correct development of the maxilla and mandible by using removable dental prostheses and to guide the eruption of the permanent molars. Removable acrylic prostheses were provided for two children, with a special metallic s-shaped handle (ansa), which guided the eruption of the first permanent molars. These prostheses were modified as the children grew. By replacing missing teeth, several oral functions were re-established, development of the maxilla and mandible was promoted, and each child could develop socially from a psychologic point of view. The use of removable dental prostheses in preschool-aged children presenting with considerable tooth loss can be a viable and successful treatment option. 相似文献
53.
Summary The aim of the present study was to compare the personality pattern, the anxiety level and the temporomandibular disorders (TMD) between bruxist and non-bruxist children with mixed dentition. Fifty-two subjects, with a mean age of 9·45 years (range 8–11) were evaluated and classified as bruxist ( n = 26), according to the American Academy of Sleep Medicine (AASM) and the presence of dental wear clinically visible, under the same conditions of artificial light and position. The control children ( n = 26) did not present dental wear and did not accomplished all the AASM criteria. The personality pattern and the anxiety of the bruxist children were studied by means of the Children's Personality Questionnaire (CPQ) and the Conners' Parents Rating Scales (CPRS), respectively, and compared with the personality traits and the anxiety level of a non-bruxist population. The TMD were also evaluated using the Research Diagnostic Criteria for temporomandibular disorders (RDC/TMD) criteria. The data were analysed with the student's t -test, Fisher's exact test and chi-squared tests. A multivariated analysis was performed using a logistic regression with the stepwise likelihood ratio method. Compared with the controls, the bruxist children had significantly higher tension personality and were more anxiety prone. The bruxist children presented more TMD-related signs and symptoms than children in the control group. A strong correlation was found among bruxism, TMD, the high anxiety level and the high tension personality trait. 相似文献
54.
Joskow R Barr DB Barr JR Calafat AM Needham LL Rubin C 《Journal of the American Dental Association (1939)》2006,137(3):353-362
BACKGROUND: Bisphenol A (BPA) is a common component of composites and dental sealants. The potential exists for human exposure after sealant placement. METHODS: The authors prospectively enrolled 15 men in an exposure assessment study; 14 completed the study. After placement of clinically appropriate amounts of one of two sealants, the authors measured BPA in saliva and urine samples collected at prescribed intervals after the sealants were placed. They used selective and sensitive isotope-dilution mass-spectrometry-based methods for BPA measurements, thus providing the most reliable results. RESULTS: Helioseal F (Ivoclar Vivadent, Amherst, N.Y.) leached negligible amounts of BPA. Urinary and salivary BPA levels in subjects who received these sealants were similar to baseline levels. Delton Light Cure (LC) Opaque pit-and-fissure sealant (Dentsply/Ash, York, Pa.) leached more BPA, resulting in low-level BPA exposures similar to those used in laboratory animal testing. BPA exposure after Delton LC sealant placement was significantly higher than exposure after placement of Helioseal F. Patients treated with Delton LC had significantly higher doses of BPA (110 microg) than did those treated with Helioseal F (5.5 microg) (P < .0001). CONCLUSIONS: Placement of clinically relevant amounts of Delton LC sealant resulted in low-level BPA exposure; however, exposure was negligible after placement of Helioseal F. Saliva collection after sealant placement likely reduced systemic absorption of BPA from dental sealants. Sealants should remain a useful part of routine preventive dental practice, especially those that leach negligible amounts of BPA. CLINICAL IMPLICATIONS: Dental sealants may be a point source for low-level BPA exposure at levels that show health effects in rodents. Further research is required to determine whether human exposure to BPA at these levels causes adverse effects. 相似文献
55.
Florian Friedmacher Naho Fujiwara Alejandro D. Hofmann Hiromizu Takahashi Luis A.J. Alvarez Jan-Hendrik Gosemann Prem Puri 《Journal of pediatric surgery》2014
Background/purpose
Prenatal administration of all-trans retinoic acid (ATRA) has been shown to stimulate alveolarization in nitrofen-induced pulmonary hypoplasia (PH) associated with congenital diaphragmatic hernia (CDH). Lipid-containing interstitial lipofibroblasts (LIFs), characterized by adipocyte differentiation-related protein (ADRP), play a critical role in alveolar development by coordinating lipid homeostasis. Previous studies have demonstrated that ATRA positively affects LIF expression in developing lungs. We hypothesized that pulmonary LIF expression is increased after prenatal ATRA treatment in the nitrofen model of CDH-associated PH.Methods
Timed-pregnant rats were treated with nitrofen or vehicle on E9.5, followed by injection of ATRA or placebo on E18.5, E19.5, and E20.5. Fetal lungs were dissected on E21.5 and divided into Control + Placebo, Control + ATRA, Nitrofen + Placebo, and Nitrofen + ATRA. Pulmonary gene expression levels of ADRP were analyzed by quantitative real-time polymerase chain reaction, and LIF expression was investigated by ADRP immunohistochemistry, oil-red-O-, and immunofluorescence-double-staining.Results
Relative mRNA expression of pulmonary ADRP was significantly increased in Nitrofen + ATRA compared to Nitrofen + Placebo (0.31 ± 0.02 vs. 0.08 ± 0.01; P < 0.0001). ADRP immunoreactivity and oil-red-O-staining were markedly increased in alveolar interstitium of Nitrofen + ATRA compared to Nitrofen + Placebo. Immunofluorescence-double-staining confirmed markedly increased LIF expression in alveolar walls of Nitrofen + ATRA compared to Nitrofen + Placebo.Conclusions
Increased LIF expression after prenatal treatment with ATRA in nitrofen-induced PH suggests that ATRA may have a therapeutic potential in attenuating CDH-associated PH by stimulating alveolar development. 相似文献56.
Maria M. Farias Constanza Gajardo Veronica Alvarez Ada Cuevas Maria L. Perez-Cotapos 《Obesity surgery》2014,24(10):1826-1829
Background
Bariatric procedures have beneficial effects on metabolic disturbances, including dermatological conditions. Short-term skin reactions associated with sleeve gastrectomy are not described in the literature.Methods
We reviewed our database for patients who underwent bariatric surgery between May and October 2013 who reported a cutaneous rash during the short-term post-surgical period.Results
Of a total of 195 patients, 8 (0.02 %) developed acute skin reactions during the first 3 months. Case 1 was compatible with reticulated papillomatosis. Case 2 was diagnosed as recurrent angioedema. Cases 3, 4, and 7 presented a cutaneous drug reaction to vitamin supplementation. Cases 5, 6, and 8 seemed to be secondary to xerosis and responded to lubrication.Conclusion
Acute cutaneous skin reactions after bariatric surgery are unusual. When they do occur, they appear to be benign conditions. 相似文献57.
Benjamin Straube Antonia Green Katharina Sass Tilo Kircher 《Schizophrenia bulletin》2014,40(4):936-944
The left superior temporal sulcus (STS) plays an important role in integrating audiovisual information and is functionally connected to disparate regions of the brain. For the integration of gesture information in an abstract sentence context (metaphoric gestures), intact connectivity between the left STS and the inferior frontal gyrus (IFG) should be important. Patients with schizophrenia have problems with the processing of metaphors (concretism) and show aberrant structural connectivity of long fiber bundles. Thus, we tested the hypothesis that patients with schizophrenia differ in the functional connectivity of the left STS to the IFG for the processing of metaphoric gestures. During functional magnetic resonance imaging data acquisition, 16 patients with schizophrenia (P) and a healthy control group (C) were shown videos of an actor performing gestures in a concrete (iconic, IC) and abstract (metaphoric, MP) sentence context. A psychophysiological interaction analysis based on the seed region from a previous analysis in the left STS was performed. In both groups we found common positive connectivity for IC and MP of the STS seed region to the left middle temporal gyrus (MTG) and left ventral IFG. The interaction of group (C>P) and gesture condition (MP>IC) revealed effects in the connectivity to the bilateral IFG and the left MTG with patients exhibiting lower connectivity for the MP condition. In schizophrenia the left STS is misconnected to the IFG, particularly during the processing of MP gestures. Dysfunctional integration of gestures in an abstract sentence context might be the basis of certain interpersonal communication problems in the patients.Key words: coverbal gestures, integration, fMRI, psychophysiological interaction, concretism 相似文献
58.
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60.
The Adult Macaque Spinal Cord Central Canal Zone Contains Proliferative Cells And Closely Resembles The Human 下载免费PDF全文
Clara Alfaro‐Cervello Arantxa Cebrian‐Silla Mario Soriano‐Navarro Patricia Garcia‐Tarraga Jorge Matías‐Guiu Ulises Gomez‐Pinedo Pilar Molina Aguilar Arturo Alvarez‐Buylla Maria‐Rosario Luquin Jose Manuel Garcia‐Verdugo 《The Journal of comparative neurology》2014,522(8):1800-1817
The persistence of proliferative cells, which could correspond to progenitor populations or potential cells of origin for tumors, has been extensively studied in the adult mammalian forebrain, including human and nonhuman primates. Proliferating cells have been found along the entire ventricular system, including around the central canal, of rodents, but little is known about the primate spinal cord. Here we describe the central canal cellular composition of the Old World primate Macaca fascicularis via scanning and transmission electron microscopy and immunohistochemistry and identify central canal proliferating cells with Ki67 and newly generated cells with bromodeoxyuridine incorporation 3 months after the injection. The central canal is composed of uniciliated, biciliated, and multiciliated ependymal cells, astrocytes, and neurons. Multiciliated ependymal cells show morphological characteristics similar to multiciliated ependymal cells from the lateral ventricles, and uniciliated and biciliated ependymal cells display cilia with large, star‐shaped basal bodies, similar to the Ecc cells described for the rodent central canal. Here we show that ependymal cells with one or two cilia, but not multiciliated ependymal cells, proliferate and give rise to new ependymal cells that presumably remain in the macaque central canal. We found that the infant and adult human spinal cord contains ependymal cell types that resemble those present in the macaque. Interestingly, a wide hypocellular layer formed by bundles of intermediate filaments surrounded the central canal both in the monkey and in the human, being more prominent in the stenosed adult human central canal. J. Comp. Neurol. 522:1800–1817, 2014. © 2013 Wiley Periodicals, Inc. 相似文献