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991.
992.
A case of undifferentiated carcinoma arising in the minor salivary gland is reported. Preoperative chemotherapy, surgery and postoperative immunotherapy were performed and good results were obtained for 15 months after surgery. However, metastasis to the lung occurred 18 months after surgery. The histologic diagnosis, clinical findings and origin of this tumor are discussed.  相似文献   
993.
994.
Serum proteins, serum iron and total iron binding capacity were estimated in 50 patients with oral submucous fibrosis and 50 patients with oral leukoplakia. The values were compared with that of 50 age- and sex-matched controls. A significant depression in hemoglobin and serum iron was observed in both groups of patients, whereas total iron binding capacity showed significant change only in the oral submucous fibrosis patients. Serum protein values were significantly lower in all the patients. The role of iron deficiency anemia in the causation of this premalignant lesion is discussed.  相似文献   
995.
Total hemolytic complement (CH50) and its fractions (C3 and C4) were estimated in the sera of 50 patients with oral leukoplakia, 50 patients with oral submucous fibrosis and 50 oral cancer patients. The values were compared with that of 50 normal controls. No significant alterations in the values of CH50, C3 or C4 were observed in the sera of patients with either leukoplakia or oral submucous fibrosis whereas the values were found to be altered significantly in oral cancer (P less than 0.001). In the case of oral submucous fibrosis the mean complement levels were slightly lower than those of normal controls and leukoplakia. Age and sex had no influence either on the total complement activity or its fractions (C3 and C4). The serum complement levels may be useful as a biological marker for the early detection of tissue dysplasia.  相似文献   
996.
997.
Facial expressions and body language constitute a major component of communication in the human population. There are no studies in the dental literature that have examined children's ability to recognize facial expressions. The purpose of this study was to determine children's accuracy and latency to respond to facial expressions (photographs) as a function of age and sex. Sixty children were recruited randomly and placed into three groups according to their age (3, 6, and 9 years) with 20 children per group. They were shown photographs of three different emotions (happiness, anger, and sadness) expressed by actors at three different exposure times (0.2, 0.5, and 1.0 sec), tachistoscopically. The children's responses (accuracy and latency) were recorded. The results indicated that three year olds were significantly less accurate and took longer to respond than the older children. Factors that may have influenced the results and clinical implications are discussed.  相似文献   
998.
beta-Adrenergic stimulation with 10 microM isoproterenol increased the [3H]-mannose/[14C]-leucine ratio (three- to six-fold) of protein extracts in double-radiolabelled rat parotid acinar cells. Characteristics of oligosaccharides in a major parotid glycoprotein (Mr approximately 220,000; gp 220) were studied. Gp 220 from control and experimental cells was endoglycosidase H-insensitive, endoglycosidase F-sensitive and bound both concanavalin A and wheat germ agglutinin. Gp 220 was removed from concanavalin A-Sepharose by sequential elution with 10 mM alpha-methyl glucoside and 0.5 M alpha-methyl mannoside. These findings suggest that (1) oligosaccharides in gp 220 have both a biantennary complex and hybrid oligosaccharide chains, and (2) beta-adrenoreceptor stimulation has little effect on the gross oligosaccharide structures of this glycoprotein.  相似文献   
999.
A case of unilateral enlargement of the coronoid process of the mandible is presented. The patient, a 37-year-old woman complained of restricted mandibular movement and swelling in the left zygomatic region. Coronoidectomy was performed intraorally, producing improved mandibular movement. The specimen consisted of a large amount of cartilage and mature bone. Most of the cartilage showed a marked disturbance in endochondral ossification. The histopathological diagnosis was osteochondroma. A review of the basic nature of the disease in the reported cases is presented. The value of computed tomography in deciding on a surgical procedure is briefly mentioned.  相似文献   
1000.
Enzymatic hydrolysis of (di)methacrylates and their polymers   总被引:1,自引:0,他引:1  
Di- and monomethacrylates hydrolyze to methacrylic acid and the alcohol part at neutral pH catalyzed by an unspecific esterase (hydrolase) and by enzymes in saliva. The rate constants of the enzymatic hydrolysis of various (di)methacrylates increase in the following order: HPMA less than BISGMA less than LAMA less than DECMA less than TEGDMA less than UEDMA less than DEGDMA. Esterase added to aqueous slurries of various powders made of polymerized BISGMA/TEGDMA-mixtures gave rise to liberation of methacrylic acid, presumably deriving from degradation of those of the dimethacrylates only bonded in the matrix by one end of the molecule. It was estimated that a TEGDMA-polymer will be hydrolyzed faster than a BISGMA-polymer. It is proposed that hydrolases in saliva increase the wear rate of composite resin fillings.  相似文献   
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