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151.
The aim of the present study was to clinically evaluate fissure sealants on the occlusal fissures and buccal pits of permanent first and second molars after 20 and 15 years, respectively. The population consisted of 72 children, each of whom had had their four first molars sealed between 1977 and 1980. At the annual examinations, all caries-free, newly erupted second molars were sealed. When sealant was applied to the second molars, the first molars were checked and sealant was reapplied to those that had deficient sealants. At the follow-up, when the subjects were 26–27 years of age, 27 in the original group had moved from the community. Thus, the present result is based on 45 subjects. One hundred and fifty-three sealed first molars and 161 sealed second molars were available for inspection. At the follow-up examination of the first molars 20 years after sealant had been applied, 65% showed complete retention, 22% partial retention without caries, and 1306 caries or restoration in the occlusal fissures or buccal pits. At the 15-year follow-up of the second molars, the corresponding figures were 65%, 30% and 5%, respectively. Of the restored or carious molars, significantly more were found in the mandible than in the maxilla ( P  < 0.001). This longitudinal study showed that pit and fissure sealants, applied during childhood, have a long-lasting, caries-preventive effect.  相似文献   
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脊髓成血管细胞瘤的MRI诊断   总被引:1,自引:0,他引:1  
目的 探讨脊髓成血管细胞瘤的MRI特征。材料与方法 5例经手术病理证实的脊髓成血管细胞瘤患者,男1例,4例,年龄25-63岁,平均37岁。全部采用超导MRI系统检查。结果 5例成血管细胞瘤发生于颈髓和胸髓。根据其MRI表现,可分为大囊小结节和实质性胪块型。在增强MRI上,壁结节及实性结节肿块皆呈明显均匀强化。3例肿块内及周围可见流空血管。结论 脊髓成血管细胞瘤的MRI特征为:易囊性变,囊结节及实性部分明显强化并可见流空血管。  相似文献   
156.
杨解人  李庆平  饶曼人 《药学学报》1992,27(10):729-733
大鼠ip前胡丙素(Pra-C 15 mg/kg,bid×3d)和硝苯啶(Nif 60μg/kg,bid×3d),使离体缺血再灌注工作心脏的收缩(AP,LVSP,+dP/dtmax)舒张(-dP/dtmax LVEDP和T值)性能在35min时得到改善,尤以舒张性能改善明显,并能促进CO,CF,SV及HR恢复,改善心脏工作效率,减少CK释放和心肌线粒体钙含量,表明Pra-C和Nif对心肌缺血都有保护作用,Pra-C的效应与Nif相近。  相似文献   
157.
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PJM GEORGE  MR Hetzel    FJC MILLARD 《Thorax》1988,43(3):218
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158.
Interleukin-6 (IL-6) is a multifunctional cytokine that plays a role in regulation of hematopoiesis. Because IL-6 is coinduced with colony- stimulating factors (CSFs) by various cell types in response to stimulation with IL-1, we investigated whether IL-6 is involved in the IL-1-induced production of CSF by human bone marrow (BM) cells in long- term culture or human fibroblasts. We showed that IL-6 does not induce CSF production by these cells. Neither addition of exogenous IL-6 nor neutralization of endogenous production of IL-6 by an anti-IL-6 monoclonal antibody (MoAb) diminished the IL-1-induced colony- stimulating activity (CSA), indicating that IL-6 did not act synergistically with IL-1. Finally, IL-6 did not influence the kinetics of IL-1-induced CSA production by human fibroblasts. We conclude that IL-6, either alone or in combination with IL-1, does not induce CSF production by human BM stromal cells or fibroblasts.  相似文献   
159.
BACKGROUND: Dyskeratosis follicularis (Darier's disease) is rare autosomal dominant disease characterized by the loss of adhesion between epidermal cells and by abnormal keratinization. METHODS: We performed a retrospective study of all the patients diagnosed with Darier's disease at the Department of Dermatology of Charles Nicolle Hospital of Tunis, between 1971 and 2002. RESULTS: During the observation period, we identified 12 patients with Darier's disease; five males and seven females with a mean age of 17.36 years. No family history was found in eight patients. Skin lesions in the form of keratotic papules were noted in seborrhoeic areas, essentially the face (nine patients), chest and scalp. Seven patients had nail lesions. UV light exposure exacerbated the disease symptoms in seven cases. The patients were treated with topical and systemic retinoids (six cases). CONCLUSION: Although Darier's disease has a chronic course, most patients manage to lead a relatively normal life. Treatment is usually unsatisfactory despite much progress in understanding of the underlying abnormalities in Darier's disease.  相似文献   
160.
OBJECTIVES: To evaluate the relative frequencies and molecular epidemiological features of viral hepatitis types B and C in dermatological patients in our geographical area. METHODS: We determined the hepatitis B virus (HBV) and hepatitis C virus (HCV) antibodies and the hepatitis B virus surface antigen (HBsAg) in a cohort of 677 dermatological patients admitted to the Department of Dermatology of Palermo. An 8-mL blood sample was taken from all subjects. The following assays were used: HBsAg, anti-HB core (antigen) (anti-HBc), anti-HB surface (antigen) (anti-HBs), anti-HB early (antigen) (anti-Hbe) and anti-HCV antibodies using enzyme-linked immunosorbent assay. RESULTS: One hundred and eighty-nine (27.91%) of the 677 dermatological patients were positive for anti-HBc, anti-HBs, anti-HBe and/or anti-HCV antibodies. In particular 22% (149 patients) were anti-HBc, anti-HBs or anti-HBe positive, reflecting exposure to HBV, and six patients (0.88%) were chronic carriers of HBsAg; 2.36% of the dermatological patients (16 persons) were anti-HCV positive. Tests showed that 24 subjects (3.52%) were infected with hepatitis B or C. The peaks in the age bands were in the 55-80-year-old age groups. CONCLUSIONS: This study confirms a high rate of HBV and HCV exposure with chronic carriers in our dermatological patients. We assume that the high prevalence of HCV and HBV in dermatological patients is more likely to be age related than to represent a true and direct association with dermatological diseases in general. Definite conclusions will only be available after large epidemiological studies that can establish or refute an aetiological and pathogenetic role of HBV and HCV in certain skin diseases associated with liver infection.  相似文献   
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