青少年学习成绩与心理卫生关系的研究

目的 了解青少年学习成绩与卫生之间的关系。方法 选择4所不同的类型的中学，根据学习成绩将入组学生分为4个组，用青少年自评行为量表（YSR）作为主要研究工具。结果 4组学生YSR量表各因子分及总分之间比较均有显著差异。3类不同类型党校的学生YSR量表部分因子及总分之间比较有显著差异。学习成绩较差的学生具有发生心理卫生问题的高危险性，因子分析显示行为问题发生率较高，其次是学习成绩优秀的学生，表现为情绪问题发生率较高。结论 研究结果显示学习成绩与青少年心理卫生状况具有密切关系。     

Metformin-associated lactic acidosis: a rare or very rare clinical entity?

AIMS: Lactic acidosis is a well recognized complication of biguanide therapy which is potentially serious. Although the prevalence of metformin-associated lactic acidosis (MALA) is much lower than that associated with phenformin, it is still being reported sporadically which raises concerns for the practising clinicians. We review the currently available world-wide data of the prevalence of MALA, the risk factors for its development and the current practical guidelines on the use of metformin to minimize the risk of this potential hazard. METHODS: An extensive literature search was conducted from both Medline and Ovid (1965-98) using the following keywords: 'Type 2 diabetes mellitus', 'oral hypoglycaemic drugs', 'biguanides', 'metformin-associated lactic acidosis' and 'renal impairment'. RESULTS: MALA was found to be a very rare clinical entity, being 20 times less common than phenformin-associated lactic acidosis. Amongst all the risk factors, renal impairment appears to be the major precipitating factor for the development of MALA in metformin-treated patients. We also found cases of MALA where no precipitating factors were identified and the underlying mechanism in these cases remains unclear. Practical recommendations of metformin use to minimize the risk of MALA have been listed based on previous reports. CONCLUSIONS: The low prevalence of MALA is comparable to the prevalence of sulphonylurea-induced hypoglycaemia. Metformin has many beneficial metabolic effects in the management of Type 2 diabetes mellitus. Provided that the recommended guidelines for metformin use are strictly adhered to, its widespread use would be safe and the incidence of MALA will be further reduced.     

In vitro and in vivo evaluation of a bondable compact for the prolonged delivery of triamcinolone acetonide to the oral cavity in patients with lichen planus

Compacts weighing 40 mg and containing triamcinolone acetonide 70-90% and polyhydroxybutyric acid (PHB) 30-10% or poly (DL-lactic acid) 20% with a diameter of 5 mm were bonded onto the side-wall of molar teeth. In vitro dissolution studies showed the compacts to release 12% of drug in 30 days with an initial burst effect. Drug loading or polymer matrix type had little effect. In vivo studies in dogs showed that compacts containing 80% drug in PHB produced salivary levels of triamcinolone acetonide for 30 days. When evaluated in five patients with lichen planus resistant to conventional therapy, these compacts produce a slight clinical improvement in three subjects. Differential scanning calorimetry studies confirmed that the drug and polymer were present as a physical mix in these compacts.     

MRI diagnosis of delayed presentation of traumatic diaphragmatic hernia

Traumatic rupture of the diaphragm may go unrecognized in patients with multiple injuries to the abdomen and chest. The majority of undiagnosed diaphragmatic ruptures will eventually become symptomatic and are associated with a high mortality rate if not treated immediately. Multiplanar imaging with magnetic resonance (MR) provided a definitive diagnosis of delayed presentation of traumatic diaphragmatic hernia.     

Relationship of gingival thickness and bleeding to loss of probing attachment in shallow sites following nonsurgical periodontal therapy

Periodontal sites of shallow initial probing depth often seem to lose probing attachment following various types of periodontal therapy, including nonsurgical therapy. The susceptibility to this treatment-associated probing attachment loss may conceivably be related to gingival architecture as well as to the inflammatory status of the tissues. This study was designed to study the relationship of buccolingual gingival thickness and bleeding on probing in shallow buccal sites (less than or equal to 3.5 mm probing depth) to loss of probing attachment following nonsurgical therapy. 3 months following treatment consisting of oral hygiene instruction and supra- and subgingival debridement, thin (less than or equal to 1.5 mm), initially non-bleeding sites displayed a mean loss of probing attachment of 0.3 mm. Thick (greater than or equal to 2.0 mm), non-bleeding sites displayed a less noticeable mean loss of probing attachment, whereas bleeding sites of both categories of gingival thickness showed a tendency towards gains in probing attachment levels. It may be concluded that the mean loss in probing attachment levels, commonly seen for shallow sites post-therapy, may be primarily due to the changes in shallow, thin healthy areas.