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111.
Henry Jeanneret was a pioneer Australian dentist, perhaps the first in this country to promote the discipline of dentistry as distinct from medicine and general surgery. This profile describes his early life and training, his emigration to Australia, his clinical practice in Sydney and in Van Diemen's Land, and his contributions to natural history, particularly in the field of botany.  相似文献   
112.
Thirty-four (17 paired) extracted second primary molars were obtained from 17 individuals (9 boys and 8 girls) aged from 9 yr 2 months to 12 yr 7 months. A tooth on one side was extracted as a control, and an acidulated phosphate fluoride (APF) gel was then applied to the paired contralateral second primary molar. Three months later, the experimental tooth was extracted. Nine sites were assayed by a microsarapling technique from small areas of the approximal enamel surface. The fluoride and phosphorus concentrations were determined by a fluoride electrode and by colorimetric procedure, respectively. Fluoride concentrations were higher in the teeth treated with the APF gel than in the control teeth. The highest fluoride uptake was observed in the central area of the approximal surfaces. Deeper areas (>10 μm) had a marked uptake of fluoride as compared with surface areas (< 3 μm). It was concluded that the APF gel application increased the fluoride levels of approximal tooth surfaces, particularly the mid-central site, of second primary molars, even at 3 months after application.  相似文献   
113.
Adult male Syrian hamsters were treated by swabbing the apex of the buccal pouch with corn oil (control, C), 1 mM benzo(a)pyrene (BP), nicotine (NC), or BP + NC in corn oil, twice daily, 5 days a week. After a 4-week treatment, the pouches and submandibular glands were dissected and used for the determination of endogenous prostaglandin (PG) production and studies on in vitro PG synthesis. Of the three PGs analysed (PGE2, PGF2 and 6-keto-PGF1), PGE2 was predominant in the pouch and the glands. BP or NC alone had only a weak effect on PG synthesis in both tissues. However, the combination of BP and NC had a synergistic effect, causing diminished PG synthesis in both tissues. In buccal pouch, BP + NC significantly decreased the concentrations of endogenous PGE2 and PGF2 (PGE2: 0.669 + 0.254 versus 1.698 + 0.460, PGF2: 0.273 ± 0.090 versus 0.625 ± 0.272 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). Similarly significant results were also found for in vitro PG synthesis (PGE2: 0.541 ± 0.249 versus 1.399 ± 0.340, PGF2: 1.045 ± 0.428 versus 2.133 ± 0.510 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). In submandibular glands, BP + NC significantly diminished the concentration of endogenous PGE2 (1.183 ± 0.175 versus 2.379 ± 0.488 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). The synthesis of 6-keto-PGF1 in both tissues, and the synthesis of PGF2 in submandibular gland, were slightly decreased with all treatments.  相似文献   
114.
A laboratory study was undertaken to determine the tensile bond strengths of three glass ionomer cements to dentine and the tensile bond strengths of composite to the three glass ionomers after etching. The tensile bond strength to untreated dentine was in the range of 4.47–5.52 MPa, being approximately twice that of a glass ionomer restorative material. After etching the glass ionomer, the bond strength to composite resin ranged from 1.83 MPa to 6.17 MPa, depending on the ionomer and on the time after mixing at which it was etched. In the majority of clinical situations, retention of a composite restoration via etched glass ionomer cement would probably need to be supplemented by additional mechanical retention.  相似文献   
115.
A bstract — Dental students, staff, and practitioners participated in an evaluation of the dental curriculum at The University of Adelaide between 1978 and 1981. The need for curriculum reform was expressed by all three groups, especially with respect to the teaching of basic sciences, some biomedical subjects, behavioural science, and practice management. Dental staff and practitioners have also indicated serious misgivings about the quality of clinical skills of new graduates. Proposals for reform are directed to resolving these and other curriculum problems revealed in the evaluation.  相似文献   
116.
INTRODUCTION With the rapid development of genetically modified foods in the world, the safety assessment of these novel foods is becoming the first task for governments, scientists, and consumers. At the same time, nutritional assessment is an important …  相似文献   
117.
118.
Immunoprecipitates of human C4 from EDTA-plasma were incubated with [14C]methylamine and analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and fluorography. In addition to finding label in the alpha-chains of the secreted (C4s) and predominant plasma (C4p) forms of C4, two additional molecules with apparent molecular weights of approximately 168,000 (p168) and approximately 125,000 (p125) covalently incorporated methylamine, indicating the presence of an internal thioester bond. These two molecules were present at a concentration of approximately 5% of total plasma C4 and were not immunoprecipitated by antisera to C3 or alpha 2-macroglobulin. A human hepatoma-derived cell line (HepG2), in addition to synthesizing C4s and small quantities of the polypeptide precursor of C4 (pro-C4), was found to secrete p168 and p125 at concentrations of 14 +/- 4.8 and 21 +/- 9.2% (mean +/- SD), respectively, of total secreted C4. These molecules were not found intracellularly. Both molecules were present on reduced, but not nonreduced, SDS-polyacrylamide gels. Chido (C4B) and Rodgers' (C4A) alloantisera precipitated the C4A and C4B variants of pro-C4, p168, p125, and C4s. Both tryptic and Staphylococcus aureus V8 protease peptide analyses showed homology between p168 and the beta- and alpha-chains and between p125 and the alpha- and gamma-chains. Partial NH2-terminal sequencing revealed that the beta-chain was NH2-terminal in p168 and that the alpha-chain was NH2-terminal in p125. Taken together, these data indicate that p168 and p125 represent uncleaved beta-alpha- and alpha-gamma-fragments of pro-C4, respectively. Thus, in most individuals, plasma C4 consists of five structurally distinct molecules, the single polypeptide precursor (pro-C4), the three-subunit secreted (C4s) and predominant plasma (C4p) forms of C4, and two incompletely processed two-subunit molecules with uncleaved beta-alpha- (p168) or uncleaved alpha-gamma (p125)-subunits. In addition, all five molecules are observed for both C4A (Rodgers) and C4B (Chido) structural genes.  相似文献   
119.
120.
目的探究乡土特色少年宫活动对学生积极心理品质的提升作用。方法采用实验组、对照组前后测实验设计,选取绵阳市某学校三年级到八年级学生共530名,随机分为实验组(n=265)和对照组(n=265)。实验组学生参与12次为期90天的乡土特色的少年宫活动,对照组处于常态。活动前后采用中国中小学生积极心理品质量表进行测量。结果①实验组和对照组在六个维度上的前测分数差异均无统计学意义(P均0.05)。②实验组在人际维度、公正维度、节制维度、超越维度上,后测分数均高于前测,差异有统计学意义(P0.05);而在认知维度和情感维度上,前、后测分数差异无统计学意义(P均0.05)。③对照组在六个维度上的前后测分数差异均无统计学意义(P均0.05)。④后测分数中,实验组在人际维度、公正维度、节制维度、超越维度上的得分均高于对照组,差异有统计学意义(P0.05);而两组在认知维度和情感维度上分数差异无统计学意义(P均0.05)。结论乡土特色的少年宫活动可能有利于提升中小学生人际、公正、节制和超越等积极心理品质。  相似文献   
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