Evaluation of the debonding characteristics of 2 ceramic brackets: an in vitro study.

The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each.     

高校辅导员职业倦怠感的产生原因及对策

本文从社会根源、组织根源及个人因素三个方面入手,对工作负荷、角色冲突与角色模糊、公平感、职业特征、人格因素等影响高校辅导员工作倦怠的主要因素进行了初步诠释,并针对三个根源因素提出相应的应对策略.     

Distribution of the exfoliative toxin D gene in clinical Staphylococcus aureus isolates in France

Exfoliative toxin D (ETD) was identified recently as a new exfoliative toxin serotype. Like other exfoliative toxins, ETD induces intra-epidermal cleavage through the granular layer of the epidermis of neonatal mice. The distribution of ETD production was investigated in Staphylococcus aureus isolates from infected and colonised patients in France. The etd gene was found in 55 (10.5%) of 522 isolates tested. Isolates responsible for bullous impetigo and generalised staphylococcal scalded skin syndrome did not harbour etd, but etd was significantly more frequent in isolates causing cutaneous abscesses and furuncles. Most etd- and Panton-Valentine leukocidin-positive strains belonged to the clone of community-acquired methicillin-resistant S. aureus spreading currently throughout France.     

Nd∶YAG激光后发性白内障切开技术的探讨

为探讨Ｎｄ∶ＹＡＧ激光治疗后发性白内障的技术问题，回顾了３４例３５只眼Ｎｄ∶ＹＡＧ激光治疗后发性白内障的类型、击发能量与脉冲、切开方法和术后效果。从Ｎｄ∶ＹＡＧ激光的聚焦、能量和切开方法的选择、病人视轴区的确定与术后并发症的观察处理方面，探讨了Ｎｄ∶ＹＡＧ激光后发性白内障的切开技术问题。结果表明，Ｎｄ∶ＹＡＧ激光治疗后发性白内障安全有效。为了避免损伤焦点周围的光学界面组织，必须有足够的功率密度和准确的聚焦，从最小能量开始，逐渐增加，直到出现切割效果。由于后发性白内障厚薄、机化程度以及有无人工晶体、虹膜粘连、后囊破裂、玻璃体脱出和偏位激光孔等不同情况，手术时选用适当的切开方法也十分重要。     

Effect of isoelectric point on biodistribution and inflammation imaging with indium-111-labelled IgG

Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.     

Negative perceptions about self-control and identification with gender-role stereotypes related to binge eating, problem drinking, and to co-morbidity among adolescents.

PURPOSE: To examine the role of both positive and negative styles of self-control, and gender-role stereotypes in binge eating and problem drinking. METHOD: Participants were 428 adolescent boys and 555 girls from predominantly Anglo-Australian backgrounds who attended regional state schools in New South Wales, Australia. Students completed standardized questionnaires that assessed problem drinking, binge eating, self-control styles, and identification with gender-role stereotypes. ANOVA and post hoc Tukey tests were conducted to examine differences among adolescents who reported problems in binge eating, drinking, and both domains. RESULTS: Adolescents who reported eating and drinking problems also reported a high negative and a low positive sense of self-control coupled with self-identification with the traits that typically describe negative dimensions of gender-role stereotypes. Regardless of gender, problem drinking was mainly related to traits of negative masculinity (bossy, noisy aggressive, etc.) whereas binge eating was mainly related to negative femininity (shy, needs approval from others, etc.). Participants who reported eating and drinking symptoms recorded low scores on positive control, high scores on negative control, and also high scores on the negative dimensions of masculinity and femininity. SUMMARY: A negative and passive style of self-control coupled with an identification with negative dimensions of gender summarizes the type of self-regulation that is implicated in both binge eating and problem drinking, and co-morbid symptoms. There is a need for interventions working toward a more balanced gender self-concept and a positive sense of self-control.     

珠子参挥发油的化学成份

利用气相色谱—质谱—计算机联用仪分析了云南省腾冲县产珠子参挥发油的成份,从中鉴定了27种化合物,测定了它们的相对含量,其中有10种倍半萜烯和一种倍半萜醇。     

Children With Chronic Physical Disorders: Maternal Reports of Their Psychological Adjustment

Advances in biomedical science have resulted in dramatic improvementsin the medical care of chronically ill and handicapped children.Past measurement problems have resulted in a lack of clarityregarding the psychological adjustment of these children. Themothers of 270 chronically ill and handicapped children wereadministered the Child Behavior Checklist in an attempt to identifypatterns of behavioral functioning across six pediatric chronicdisorders: juvenile diabetes, spina bifida, hemophilia, chronicobesity, juvenile rheumatoid arthritis, and cerebral palsy.In general, it was found that children in all chronic disordergroups were perceived by their mothers as evidencing on theaverage more behavioral and social competence problems thanexpected based on norms for children in general. However, theirbehavioral and social adjustment was reported as better thanthat of a normative sample of children referred to mental healthclinics. There were essentially no differences between childrenwith different chronic disorders in terms of behavior problemsand social competence. The results were taken to support theview that these children were as a group at risk for adjustmentproblems. They were also discussed in terms of the noncategorialapproach, which suggests that similar psychosocial challengesare faced across pediatric chronic physical disorders.     

Modulatory effect of prolactin on the resting and mitogen-induced activity of T, B, and NK lymphocytes

Prolactin (PRL) has been shown to contribute to the development of lymphoid tissues and maintenance of physiological immune function. Here we show that the role of the hormone extends to the control of the effector phase of the immune response. In addition to triggering resting lymphocytes to cell division, the hormone can also control the magnitude of their response to polyclonal stimuli. Concentrations of PRL in the physiological range increased the [3H]thymidine, [3H]uridine, and [3H]leucine incorporation of unstimulated NK cells cultured in serum-free conditions. The same concentrations of the hormone increased the response of NK, T, and B cells to the mitogenic stimuli interleukin 2 (IL2), phytohemagglutinin (PHA), and staphylococcus aureus cowan, respectively, the effect being maximally evident in the presence of suboptimal concentrations of the mitogens. By contrast concentrations of PRL five- to tenfold the physiological levels inhibited the mitogenic response to IL2 and PHA. These data indicate a double-faceted regulatory role of this hormone in vivo.     

奎硫平和利培酮治疗精神分裂症的比较研究

目的　以利培酮为对照 ,探讨奎硫平治疗精神分裂症的疗效和副作用。方法　将 79例符合CCMD 3诊断标准的精神分裂症病人随机分为两组 ,分别给予奎硫平和利培酮治疗 8周。采用阳性症状和阴性症状量表 (PANSS)评定临床疗效 ,副反应量表 (TESS)评定副反应。结果　治疗 8周后的疗效近似 (P >0 0 5 ) ;奎硫平组和利培酮组的显效率差异无显著性 (P >0 0 5 ) ;奎硫平组的副反应发生率低于利培酮组 ,但差异无显著性 (P >0 0 5 )。利培酮组锥体外系副反应和内分泌改变的发生均明显高于奎硫平组 (P <0 0 5 )。结论　奎硫平和利培酮对精神分裂症的疗效相当 ,副作用较小。