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41.
Previous research has suggested that a relationship exists between craniofacial morphology and tooth wear. The primary objective of this study was to determine whether an individual's craniofacial morphology during childhood is related to the degree of tooth wear that occurs in that same individual's adult dentition. Pretreatment orthodontic records taken during the mixed dentition (T1) and follow-up records taken an average of 20 years later (T2) were available for 165 orthodontic patients. Incisal/occlusal tooth wear was measured on a tooth-by-tooth basis from T1 and T2 casts using a four-category scoring system. Measures of craniofacial morphology were made from the T1 lateral cephalometric radiograph. Multiple regression analysis indicated that adult wear was associated with the T1 cephalometric measures of ANB (p = 0.017) and the interaction between ramal height and sex (p = 0.039). These results suggest that the craniofacial morphology observed during childhood has a small but significant relationship to adult tooth wear.  相似文献   
42.
Chlorohydroxyfuranones (CHFs) are mutagenic disinfection by-productsfound in chlorine-treated drinking water. In the current study,the genotoxicity of four CHFs, 3,4-dichloro-5-hydroxy-2(5H)-furanone(MCA), 3-chloro-4-methyl-5-hydroxy-2(5H)-furanone (MCF), 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone(CMCF) and 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone(MX), was determined. Two in vitro assays, the microscale micronucleusassay on L5178Y mouse lymphoma cells and the unscheduled DNAsynthesis assay on a hepatocyte primary culture from FisherF344 rats, were carried out. All four CHFs demonstrated genotoxiceffects in both assays. In the two systems used, CMCF was themost genotoxic compound, followed by MCA, MX and MCF, respectively.This work was the first study of the DNA damaging propertiesof all four CHFs in two in vitro genotoxicity tests. These newdata expand the range of genetic damages induced by this groupof compounds. 2 To whom correspondence should be addressed. Tel: +33 3 20 8779 14; Fax: +33 3 20 87 73 10; Email: daniel.marzin{at}pasteur-lille.fr  相似文献   
43.
Laparoscopic splenectomy in patients with hematologic malignancies   总被引:2,自引:0,他引:2  
BACKGROUND: Although laparoscopic splenectomy (LS) for benign hematologic disease is well accepted, its role in hematologic malignancies is not clearly defined. This study examined the efficacy and feasibility of LS for hematologic malignancies. METHODS: Records were reviewed from patients who underwent LS at two university hospitals. Charts from 77 open splenectomies for malignancy (OM) during the same period were also reviewed. RESULTS: Fifty-three patients underwent LS, 22 for hematologic malignancies (LM) and 31 for benign hematologic disorders (LB). Median splenic weight was greater in the LM group (930 g) than in the LB group (164 g, P = 0.001). LM was associated with longer operations and greater blood loss than was LB. LM had a 41% conversion rate. Morbidity, mortality, and transfusion rates were similar. Median hospital stay was shorter for LM (4 days) than for OM (6 days, P = 0.001). CONCLUSIONS: LS is feasible in hematologic malignancies but is associated with increased operative time and blood loss and a high conversion rate. Morbidity and mortality, however, was similar. Shorter hospital stays for LM compared with OM may translate into earlier recovery and initiation of antineoplastic therapy.  相似文献   
44.
Osteochondroma and secondary synovial osteochondromatosis   总被引:1,自引:0,他引:1  
Secondary synovial osteochondromatosis (SOC) is a rare disorder caused by a variety of joint disorders. Two unusual cases of secondary SOC are presented. The first patient is a 43-year-old man with extensive SOC developing within a bursa surrounding an osteochondroma of the pubic bone. The second patient is a 23-year-old man who developed florid and progressive SOC of his hip joint following excision of a femoral neck osteochondroma. SOC recurred despite three excisions over a 15-month period. Imaging was useful in pre-operative diagnosis of bursal SOC in the first patient and in detecting multiple recurrences in the second patient. Both cases illustrate prominent SOC developing secondary to osteochondroma. The different hypotheses regarding bursal and secondary SOC are reviewed. Received: 8 October 1998 Revision requested: 28 October 1998 Revision received: 13 November 1998 Accepted: 16 November 1998  相似文献   
45.
BACKGROUND AND PURPOSE: The cross-sectional and 4-year longitudinal associations between brachial pulse pressure (PP) and ultrasound measurements of common carotid intima-media thickness (CCA-IMT) were assessed. METHODS: A population of 957 volunteers aged 59 to 71 years was recruited from the electoral rolls of the city of Nantes (western France) and reexamined 4 years later. Longitudinal changes in PP and CCA-IMT were computed as the difference between 4-year follow-up and baseline values. RESULTS: Baseline CCA-IMT and PP were positively associated in both age- and sex-adjusted analysis (partial correlation coefficient=0.20, P<0.001) and in multivariate analysis adjusted for traditional cardiovascular risk factors and mean blood pressure (partial correlation coefficient=0.18, P<0.001). In longitudinal analysis, baseline PP was associated with the change in 4-year CCA-IMT (partial correlation coefficient=0.11, P<0.001), and baseline CCA-IMT was a predictor of the 4-year change in PP (partial correlation coefficient=0.10, 0.001相似文献   
46.
Studies of minority ethnic women and cancer screening have, in the past, suffered from many theoretical and methodological weaknesses. In addition, no attempts have been made to study the complexity of the issue involved in the intercultural context, or the possible contribution of women's experiences to low uptake rates. In order to further our understanding of the issues, an alternative approach, participatory action research (PAR), was adopted to identify factors that might have contributed to the persistently low participation of minority ethnic women in the cervical screening programme, and address them collaboratively. This paper presents the key findings of the ‘problem identification' phase of the project. Using mainly the focus-group method, it explores both smear takers' and minority ethnic women's perceptions and experiences of cervical screening. Data suggest that there was a divergence in perceptions held by these groups regarding cervical screening, which contributed to negative experiences for both groups. There is also clear evidence of dysfunctional clinical communication arising from these differing perceptions. Opportunistic screening at post-natal examination adopted by many general practices appeared to have perpetuated the perceptions that the majority of minority ethnic women held about the purpose of the smear test. Compounded by language differences, the majority of women who had undergone smear testing understood neither the purpose of screening programme nor the procedure of the test. This has clear implications for promoting regular uptake, and more importantly for informed consent and choice.  相似文献   
47.
48.
From a total material of 184 Swedish users of loose packed moist snuff and 68 users of portion-bag packed moist snuff, cases were selected from subgroups based on a four-point clinical grading scale. The selected material for the study comprised 70 cases (ten from each clinical grade group, no Degree 4 lesion was found among portion-bag users). Features recognized in biopsies from these cases together with findings in previous studies correlated well with the use of a four-point scale for the grading of clinical changes, especially in the context of discriminating lesions for which special efforts should be undertaken to make the patient stop or change the snuff dipping habit and for selecting patients in whom regular clinical follow-up including a biopsy should be carried out. In this article is also discussed the labeling of the clinical oral mucosal changes seen at the site where a quid of snuff is regularly placed. The conceptual use of "snuff dippers' lesions" is recommended instead of e.g. snuff-induced leukoplakia.  相似文献   
49.
PURPOSE: For cancer patients receiving cytotoxic chemotherapy, hepatitis B virus (HBV) reactivation is a well described complication resulting in varying degrees of liver damage. The objectives of this study were to assess the efficacy of the antiviral agent lamivudine in reducing the incidence of HBV reactivation and diminishing morbidity and mortality of cancer patients with chronic HBV infection during chemotherapy. PATIENTS AND METHODS: Two groups were compared in this nonrandomized study. The prophylactic lamivudine group consisted of 65 patients in a phase II study who were treated with lamivudine before and until 8 weeks after discontinuing chemotherapy. The historical controls consisted of 193 consecutive patients who underwent chemotherapy without prophylactic lamivudine. Significant prognosticators for the development of HBV reactivation were determined based on data from the controls. Potential confounding factors were identified between the two groups. The outcomes were compared. RESULTS: In the controls, lymphoma and anthracycline usage were factors identified to be associated with reactivation. The two groups were comparable in most baseline characteristics, although in the prophylactic lamivudine group, there were significantly more patients with lymphoma and receiving anthracyclines. In the prophylactic lamivudine group, there was significantly less HBV reactivation (4.6% v 24.4% in the controls; P <.001), fewer incidences of hepatitis (17.5% v 44.6%; P <.0001) that were less severe (4.8% v 18.7%; P =.0005), and less disruption of chemotherapy (15.4% v 34.6%; P =.0029). The reduction in overall mortality was not statistically different. CONCLUSION: Prophylactic lamivudine significantly reduced the incidence of HBV reactivation and the overall morbidity of cancer patients undergoing chemotherapy.  相似文献   
50.
PURPOSE: To assess the efficacy of neoadjuvant paclitaxel and carboplatin (TC) followed by concurrent cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and to monitor treatment response with plasma Epstein-Barr virus (EBV) DNA. PATIENTS AND METHODS: Thirty-one patients with International Union Against Cancer stages III and IV undifferentiated NPC had two cycles of paclitaxel (70 mg/m2 on days 1, 8, and 15) and carboplatin (area under the curve 6 mg/mL/min on day 1) on a 3-weekly cycle, followed by 6 to 8 weeks of cisplatin (40 mg/m2 weekly) and RT at 66 Gy in 2-Gy fractions. Plasma EBV DNA was measured serially using the real-time quantitative polymerase chain reaction method. Results All patients completed planned treatment. Response to neoadjuvant TC was as follows: 12 patients (39%) achieved partial response (PR) and 18 achieved (58%) complete response (CR) in regional nodes; five patients (16%) achieved PR and no patients achieved CR in nasopharynx. At 6 weeks after RT, one patient (3%) achieved PR and 30 patients (97%) achieved CR in regional nodes, and 31 patients (100%) achieved CR in nasopharynx; 29 patients (93%) had EBV DNA level of less than 500 copies/mL. Neoadjuvant TC was well tolerated, and the most common acute toxicity of cisplatin plus RT was grade 3 mucositis (55%). At median follow-up of 33.7 months (range, 7 to 39.3 months), six distant and three locoregional failures occurred. Plasma EBV DNA level increased significantly in eight of nine patients who experienced treatment failure but did not increase in those who did not. The 2-year overall and progression-free survival rates were 91.8% and 78.5%, respectively. CONCLUSION This strategy was feasible and resulted in excellent local tumor control. Serial plasma EBV DNA provides a noninvasive method of monitoring response in NPC.  相似文献   
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