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51.
52.
Although variation in finishing techniques has been shown to affect microleakage, little research has been published on the influence of finishing time on the marginal sealing ability of new generation composite bonding systems. The objective of the present study was to evaluate the influence of finishing time on the enamel and dentine marginal sealing ability of four new generation composite systems. Two class V preparations, which were solely in enamel or dentine, were made on the buccal surfaces of 96 freshly extracted molar teeth. The teeth were randomly divided into four groups of 24 and restored with composite resin (Silux Plus®) utilizing the following bonding systems: Scotchbond Multi-purpose®, Fuji Bond LC®, Prime & Bond 2·0® and Bisco One-step®. Half of the restorations in each group were finished immediately after light polymerization and stored for 1 week. For the remaining restorations, finishing was delayed for 1 week. The storage medium was isotonic saline at 37°C throughout the experiment. All restorations were then thermocycled, subjected to dye penetration testing, sectioned and scored. The results suggest that the finishing of composite restorations, bonded with the bonding systems evaluated, should be carried out immediately after light polymerization. Delayed finishing does not improve but instead can be detrimental to the marginal seal of the restorations. The effects of delayed finishing are, however, both bonding system and tissue specific.  相似文献   
53.
OBJECTIVES: The impact of command hallucinations on patients and the determinants of patients' compliance with them are still poorly understood. The extant literature is also divided on their association with violence. This study aimed to establish the prevalence of command hallucinations and to identify the factors that affect compliance with the commands, together with patients' coping methods. METHODS: We recruited 50 consecutive male and 50 consecutive female schizophrenia inpatients who reported hearing voices in the 6 months prior to admission. We interviewed these patients, using a semistructured questionnaire. We collected information on the contents of their auditory hallucinations and their coping methods. RESULTS: Of the patients, 53 (53%) reported command hallucinations. Of these 53 patients, 58% were women and 48% were men; 62% reported complying with the commands. They were also more likely to comply with nonviolent commands. A history of self-harm predicted compliance. Those patients who did not comply with the commands adopted various methods of coping, of which praying was the most common. CONCLUSION: Command hallucinations are common in patients with schizophrenia. Patients with a history of self-harm need closer monitoring because they may be more likely to comply with these hallucinations. Assessment should also include the patient's own coping strategies, which can be incorporated into the treatment.  相似文献   
54.
A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease.  相似文献   
55.
Two new nitro analogs of tranylcypromine, (E)-2-(p-nitrophenyl)cyclopropylamine ((E)-p-NTCP) and (E)-2-(m-nitrophenyl)cyclopropylamine ((E)-m-NTCP) were synthesized in order to examine the effect of aromatic nitro substitution on the MAO-inhibitory activity of 2-phenylcyclopropylamines. The compounds were obtained by treatingt-butyl (E)-2-(p-nitrophenyl) cyclopropanecarbamate andt-butyl (E)-2-(m-nitrophenyl)cyclopropanecarbamate withp-toluenesulfonic acid in CH3CN. Inhibitions of rat brain mitochondrial MAO-A and B by the compounds were examined using serotonin and benzylamine as the substrate at bothin vitro andex vivo levels. It was found fromin vitro measurements that(E)-p-NTCP at 6.0×10?5M elicited merely 22.5% inhibition against MAO-B without any effect on MAO-A. In contrast,(E)-m-NTCP showed fair degrees of inhibitions of MAO-A and B with IC50 values, 2.5×10?7M and 1.4×10?6M, respectively. It was also noted from(E)-m-NTCP thatm-nitro substitution caused a shift of selectivity of the inhibition toward MAO-A. According toex vivo measurements at 1.5, 3, 6, and 12 hr following the administration of a dose of 0.015 mmol/kg, i.p. to the rats, the inhibition percents of MAO-A by(E)-m-NTCP were 58.6, 63.7 63.6, and 46.6%, slightly lower than those observed by tranylcypromine. Whereas,(E)-p-NTCP at the same dose level did not show significant inhibitions against both MAO-A and MAO-B. Possible reasons for the difference in potencies between(E)-m-NTCP and(E)-p-NTCP were sought in relation to differing electron withdrawing effects ofm-andp-substituents which will influence electron density of the side chain amino functions and the partitions.  相似文献   
56.
A panel of P1 synthetic peptides was synthesized to map the surface-exposed epitopes of Haemophilus influenzae type b outer membrane protein P1 recognized by three murine monoclonal antibodies (MAbs 7C8, 3E12, and 6B1). By using peptide-specific enzyme-linked immunosorbent assays, MAbs 6B1, 7C8, and 3E12 were shown to recognize distinct epitopes localized within residues 60 to 88, 165 to 193, and 400 to 437 of mature P1, respectively. Since MAb 7C8 was shown previously to be protective against certain H. influenzae type b subtypes in the infant rat model of bacteremia, its cognate epitope was further characterized by using truncated peptide analogs. Fine mapping of the 7C8 epitope by competitive inhibition studies revealed that it was localized within residues 184 and 193.  相似文献   
57.
目的:探讨人类恶性畸胎瘤PA-1细胞株染色体特性及其影响因素。方法:采用G带核型分析、DNA碱基序列分析及Western blot(蛋白印迹分析)等方法对经20余年407-445继代培养的PA-1细胞株染色体核型及p 53 基因状态进行了研究。结果:PA-1细胞株80%以上仍然保持近乎二倍体的核型,30代以后的细胞由于第15号染色体与20号染色体间的相互易位形成了M1及M2标识染色体。RT-PCR产物DNA定向序列分析显示具有野生及突变两个带(p53密码子239突变),Western blot 未检测出突变的p53基因蛋白,而p21蛋白的表达水平比正常成纤维细胞低。结论:人卵巢恶性畸胎瘤PA-1细胞株经20年的继代培养后,一个p53 等位基因发生错义突变,另一个仍然是野生型的。仅一个p53 等位基因发生突变,不足以引起细胞的染色体不稳定性。  相似文献   
58.
We provided a curve-fit equation to predict the normal heart weight (g) in Koreans by examining 422 autopsies (215 males and 207 females, from newborn to age 77 yr) who were relatively in good general condition. Heart weight was well correlated with body surface area (m2), body weight (kg), and body height (cm) but poorly with age in both sex. Heart weight progressively increased from birth to the earlier 3rd and 4th decades in male and female, respectively, and then gradually decreased; mean heart weight of all age group was greater in male than in female and significantly different from birth to 4th decade. In both sex, heart weight exponentially increased in accordance with the increase of body height, body weight, and body surface (in male, heart weight=0.00312 x body height(2.239), r2=0.750, p<0.0001; in female, heart weight=0.00443 x body height(2170), r2=0.781, p<0.0001; in male, heart weight=9.22 x body weight(0.853), r2=0.770, p<0.0001; in female, heart weight=9.00 x body weight0.855, r2=0.820, p<0.0001; in male, heart weight=155.18 x body surface area1.290, r=0.808, p<0.0001; in female, heart weight=124.13 x body surface area1.242, r=0.834, p<0.0001). These results indicate that heart weight is better correlated with body surface area than with body weight; however, body weight should be a better determinant of a predicted heart weight, since body surface area is entirely dependent on body height and body weight.  相似文献   
59.
The biomechanical properties and histocompatibility of a glutaraldehyde-treated xenograft were examined after implanting it in 27 rabbits. This xenograft was used as an Achilles tendon substitute placed in vivo for 2 to 48 wk. The specimens were then subjected to mechanical strength testing using a specially constructed tensioning device. The contralateral Achilles tendon was used as the reference baseline. Mechanical testing showed that the strength of the implanted graft increased to 33.5% of the normal side at week 10 and to 79.5% at week 14. The host generated a fibrous cord around the xenograft, linking the two ends of the Achilles tendon. Light and electron microscopic examination showed fibroblastic infiltration of varying magnitude in all specimens but no statistical correlation between degree of infiltration and duration of implantation was found. Also, there was no histological evidence of immunological rejection within the 48 wk of study.  相似文献   
60.
Streptococcus pneumoniae is an important pathogen causing invasive infections particularly in children. Penicillin-nonsusceptible pneumococci are very prevalent in Korea and a difficult problem in antimicrobial treatment. Immunization with effective vaccines including viral and bacterial vaccines has proven to be the most effective and reliable method to prevent the target disease. Universal immunization to infants with Haemophilus influenzae type b conjugate vaccine has dramatically proven to be very effective in reducing invasive Hib diseases and also the carriage rate. The 23-valent pneumococcal polysaccharide vaccine is effective in preventing invasive diseases in young adults and covers most of the penicillin-nonsusceptible types. It has not proven very effective in the prevention of otitis media, and is unable to elicit adequate antibody response in children younger than 2 years of age. Recently a new polysaccharide-protein conjugate vaccine was developed which can elicit antibody response in children younger than 2 years of age. However, the vaccine is only 8-valent at the moment. Studies are required to determine the possible idiotypic modulation and nonproductive immune response when polysaccharide vaccine is administered to infants. Part of the problem of antimicrobial-resistant pneumococcal infection may be solved in the future with the use of improved vaccine. Preventing pneumococcal infections with safe and effective vaccines will not only reduce the development of antibiotic resistance, but could also be the most cost-effective method to control pneumococcal disease.  相似文献   
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