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991.
Alloreactive CD4+ and CD8+ T cells express the immunotolerant HLA-G molecule in mixed lymphocyte reactions: in vivo implications in transplanted patients 总被引:10,自引:0,他引:10
992.
993.
Garlet GP Martins W Fonseca BA Ferreira BR Silva JS 《Journal of clinical periodontology》2004,31(8):671-679
OBJECTIVE: Inflammatory reactions raised in response to periodontopathogens are thought to trigger pathways of periodontal tissue destruction. We therefore investigated the expression of matrix metalloproteinases (MMPs) and the osteoclastogenic factor receptor activator of nuclear factor-kappaB ligand (RANKL), their respective tissue inhibitors of metalloproteinases (TIMPs) and osteoprotegerin (OPG) in different forms of human periodontal diseases (PDs), and the possible correlation with the expression of inflammatory and regulatory cytokines. MATERIAL AND METHODS: Quantitative polymerase chain reaction (real-time PCR) was performed with gingival biopsies mRNA from aggressive (AP) and chronic periodontitis (CP) patients. RESULTS: Periodontitis patients exhibit higher expression of all analyzed factors when compared with healthy tissues. The expression of MMPs and RANKL were similar in AP and CP, as well as the expression of TNF-alpha. On the other hand, the expression of TIMPs and OPG was higher in CP, and was associated with lower IFN-gamma and higher IL-10 expression, compared with AP. CONCLUSION: It is possible that the pattern of cytokines expressed determines the stable or progressive nature of the lesions and regulates the severity of PD, driving the balance between MMPs and TIMPs, RANKL and OPG expression in the gingival tissues controlling the breakdown of soft and bone tissues and, consequently, the disease severity. 相似文献
994.
Magnani MB Nouer DF Nouer PR Pereira Neto JS Garbui IU Böeck EM 《Brazilian Oral Research》2004,18(3):233-237
Black individuals present craniofacial characteristics which differ from those of other races, especially the white race, whose cephalometric analyses are usually considered as the standard in routine orthodontic diagnosis and treatment planning. Further studies are therefore needed to enable more accurate and specific diagnoses for this ethnic group. The present study was conducted in order to assess average values for the nasolabial angle in young Brazilian black individuals with normal occlusion, and to assess the occurence of sexual dimorphism. Thirty-six lateral skull, extraoral radiographs from Brazilian black individuals were selected from the archives of the Scientific Recordings Department, Orthodontics Graduate Program, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP). The patients' ages varied from 10 to 14 years, they presented normal occlusion upon clinical examination, and had not been submitted to orthodontic treatment. The cephalometric landmarks from which the nasolabial angle was obtained and measured were traced by a single researcher. Statistical analysis and evaluation of the results led to the conclusion that the nasolabial angle of young Brazilian black individuals is sharper, i.e., the soft tissue profile is more protruded. The average value for the whole sample was 88.14 degrees +/- 12.52 degrees. The nasolabial angle was statistically smaller among females (p < 0.05), demonstrating the occurrence of sexual dimorphism. 相似文献
995.
996.
Definitive neuroradiological diagnostic features of tuberculous meningitis in children 总被引:4,自引:0,他引:4
Background: Although CT scanning is used widely for making the diagnosis and detecting the complications of tuberculous meningitis (TBM) in children, the radiological features are considered non-specific. CT is particularly suggestive of the diagnosis when there is a combination of basal enhancement, hydrocephalus and infarction, and even then the diagnosis may be in doubt. In this paper we introduce a new CT feature for making the diagnosis of TBM, namely, hyperdensity in the basal cisterns on non-contrast scans, and we assess which of the recognized CT features is most sensitive and specific. Objective: To determine the sensitivity and specificity of the presence of high-density exudates in the basal cisterns (on non-contrast CT) and basal enhancement (on contrast-enhanced CT) for the diagnosis of TBM in children, and to correlate these with the complications of infarction and hydrocephalus. Materials and methods: Retrospective review of CT scans with readers blinded to the diagnosis, which was based on a definitive culture of cerebrospinal fluid (CSF) for TBM or other bacteria. Computer-aided conversion of hard-copy film density to Hounsfield units was employed as well as a density threshold technique for determining abnormally high densities. Results: The most specific feature for TBM is hyperdensity in the basal cisterns prior to IV contrast medium administration (100%). The most sensitive feature of TBM is basal enhancement (89%). A combination of features (hydrocephalus, infarction and basal enhancement) is as specific as pre-contrast hyperdensity, but has a lower sensitivity (41%). There were statistically significant differences in the presence of hydrocephalus (p=0.0016), infarcts (P=0.0014), basal enhancement (P<0.0001) and pre-contrast density (P<0.0001) between the negative and positive TBM patient groups. The presence of granulomas was not statistically significant between the two groups (P=0.44). Conclusions: The presence of high density within the basal cisterns on non-contrast CT scans is a very specific sign for TBM in children. This will enhance diagnostic confidence, allow early institution of therapy and could reduce expenditure on contrast medium, scan time and radiation exposure. With the use of threshold techniques we believe that the pre-contrast hyperdensity may be detectable by a computer program that will facilitate diagnosis, and may also be modified to detect abnormal enhancement. Basal enhancement is a sensitive sign for the diagnosis of TBM and should be sought after contrast medium administration when no hyperdensity is seen in the basal cisterns or when this finding needs to be confirmed. The CT scan feature of hyperdense exudates on pre-contrast scans should be added to the inclusion criteria for the diagnosis of TBM in children. 相似文献
997.
998.
Lazovich D Forster J Sorensen G Emmons K Stryker J Demierre MF Hickle A Remba N 《Archives of pediatrics & adolescent medicine》2004,158(9):918-924
BACKGROUND: Indoor tanning is a popular behavior that may increase skin cancer risk. OBJECTIVE: To examine characteristics associated with use or intention to use indoor tanning among adolescents. METHODS: A telephone interview was conducted with 1273 adolescents, aged 14 to 17 years, in the Minneapolis-St Paul, Minn, and Boston, Mass, metropolitan areas. Questions included demographic and phenotypic characteristics, knowledge, attitudes, social factors, use of indoor tanning, and intention to tan indoors. RESULTS: Twelve percent of boys and 42% of girls had tanned indoors. Among nontanners, 22.4% planned to start, and 77.2% of tanners planned to continue tanning indoors. Nontanners and tanners at risk for future indoor tanning use were each significantly more likely to be female, less likely to use sun protection, less knowledgeable about skin cancer risks, more likely to agree that tans were attractive, and more strongly influenced by social factors compared with their low-risk counterparts. CONCLUSIONS: Our data suggest that intention to tan indoors may identify a group of adolescents at risk for adopting the behavior; prospective studies are needed for confirmation. 相似文献
999.
Hammer SJ Backer H Schechter R 《Archives of pediatrics & adolescent medicine》2004,158(7):708; author reply 709
1000.
Hysteroscopy and three-dimensional ultrasonography in uterine diverticulum diagnosis: a case report 总被引:1,自引:0,他引:1
Schmidt AP Glitz CL Passos EP Arbo E Cunha-Filho JS 《American journal of obstetrics and gynecology》2004,190(2):561-562
The authors describe a case report of a uterine diverticulum in a postmenopausal woman with abnormal uterine bleeding, confirmed by 3-dimensional ultrasonography and hysteroscopy. They comment on the clinical significance of this rare lesion. 相似文献