指数程序升温药物稳定性试验

介绍了一种新的程序升温(指数程序升温)药物稳定性预测加速试验方法及计算方法。在这一新的程序升温方法中,温度每升高10℃,升温速率将增大2～4倍:dT/dt=a^(T-T₀)/10·(dT/dt)₀,使药物在高温和低温范围内的降解程度尽可能一致,提高了试验准确度。采用单因素优选法和数值积分法处理试验数据,避免了任何近似处理,使计算结果准确可靠。与线性升温、倒数升温和对数升温加速试验进行了对比,结果表明,指数程序升温法的准确性优于其它3种升温法。     

Cannabis withdrawal in adolescent treatment seekers

A valid cannabis withdrawal syndrome has been demonstrated in controlled studies with adult marijuana abusers, yet few published reports have examined cannabis withdrawal among adolescents. Adolescents presenting for outpatient substance abuse treatment, whose primary substance of abuse was cannabis, completed a questionnaire reporting the presence and severity of withdrawal symptoms during past periods of cannabis abstinence. Nearly two-thirds of the sample indicated that they had experienced four or more symptoms, and over one-third reported four or more symptoms that occurred at a moderate or greater severity. The magnitude of withdrawal severity was positively correlated with current emotional and behavioral symptoms and self-reported problems with cannabis use. These findings are consistent with previous studies, though the prevalence and magnitude of withdrawal symptoms were lower than that observed in a similar study with adult treatment seekers [Budney, A.J., Novy, P., Hughes, J.R., 1999. Marijuana withdrawal among adults seeking treatment for marijuana dependence. Addiction 94, 1311-1322]. Further research is needed to elucidate associations between cannabis withdrawal effects, the initiation of cessation attempts, and relapse.     

The impact of disruptive behavior disorder on substance use treatment outcome in adolescents

The current study examined the impact of disruptive behavior disorder (DBD) on substance use outcomes in an adolescent sample. Sixty-eight adolescents and their caregivers were randomized to one of two fourteen-week, outpatient treatments: Motivational Enhancement Therapy/Cognitive Behavior Therapy (MET/CBT) + Parent Management Training + Contingency Management (CM; experimental) and MET/CBT + Parent Drug Education (attention control). This study assessed abstinence, substance use, externalizing behavior, and parenting outcomes over five assessment periods for youth with DBD (DBD⁺) and without DBD (DBD⁻). Results showed DBD⁺/experimental adolescents reported fewer days of marijuana use than DBD⁺/control adolescents. Results also showed that parents of DBD⁻ adolescents in the experimental condition reported significantly better parenting outcomes compared to DBD⁻/control. Substance abuse treatment for adolescents with DBD which includes a component such as contingency management and parent training has the potential to contribute to substance use outcomes. Such treatment strategies, however, should include additional support for parents.     

The biology of organ size determination

The mechanisms that control the size of cells, organs, and organisms have long interested biologists, and are also important in malignant progression. Despite this, basic features of in vivo growth control - the level at which regulation is exerted and the degree to which size is controlled autonomously - are poorly understood. Similarly, it is unknown whether adult tissues measure and respond to size cues in the same manner as those of embryos, a question that is relevant to tissue homeostasis and regeneration. This article will review the determinants of organ size during development and discuss the concept of a 'size set-point,' which incorporates the mass of tissue parenchyma and scaffold established at the end of development.     

Asymmetrically short tendinous cords causing congenital tricuspid regurgitation: improved understanding of tricuspid valvar dysplasia in the era of color flow echocardiography.

BACKGROUND: Tricuspid regurgitation as a manifestation of an isolated congenital anomaly of the tricuspid valve is rare. Cross-sectional and color Doppler echocardiography allow improved evaluation of tricuspid valvar function. As a result, the heterogeneous category of congenital tricuspid valvar dysplasia may be better understood from a functional point of view. We are reporting a distinct entity in which tricuspid valvar regurgitation results from failure of coaptation due to short tendinous cords tethering the septal leaflet. PATIENTS AND RESULTS: Three children with significant primary tricuspid regurgitation were evaluated, treated, and followed. On echocardiographic evaluation, a central regurgitant jet of moderate or severe degree was directed toward the atrial septum through poorly coapting tricuspid valvar leaflets, which did not approximate due to tethering of the septal leaflet by abnormally short cords. In one patient, the tricuspid valve was otherwise normal; in the other two the leaflets and cords were also thickened. Two patients underwent surgery at 9 and 11 years of age. The cords tethering the septal leaflet were augmented by interposing appropriate lengths of expanded polytetrafluoroethylene suture and performing commissural annuloplasty. Both patients are asymptomatic 33 and 42 months postoperatively, with mild residual tricuspid regurgitation that has not changed since surgery. The other patient, an 8 month-old infant, has not yet undergone surgery. CONCLUSIONS: Asymmetric tendinous cords of the tricuspid valve causing tethering of the septal leaflet is a distinct cause of tricuspid regurgitation that can be recognized with echocardiography. Although rare, the importance of recognizing this lesion lies in its being readily amenable to surgical repair.     

Mothers' marital adaptation following the birth of twins or singletons: empirical evidence and practical insights

Parenting twins is typically portrayed as more stressful than is parenting single children and, therefore, more of a strain on the marital relationship. With this in mind, the present study examined the contribution of infant characteristics and mother's internal resources (attachment style) and external resources (maternal and paternal grandmothers' perceived support) to their marital adaptation during the first month following delivery, comparing mothers of twins (n = 88) with mothers of singletons (n = 82). The findings indicate that both internal and external resources contribute to the marital adaptation of the two groups, even beyond the contribution of specific circumstances. Thus, it seems that the birth of twins and the birth of a single child are normative life events that have more in common than previously acknowledged. The implications for the focus of social work interventions, particularly in the case of the birth of twins, are discussed.     

Exploring the boundary between temperament and generalized anxiety disorder: a receiver operating characteristic analysis

Studies of individuals with an increased tendency to experience negative emotions such as fear, sadness, and anger have documented links between this temperamental trait and anxiety disorders. There exists debate, however, concerning the degree to which high levels of a temperamental trait are a necessary and/or sufficient component of a DSM diagnosis. In this study, receiver operating characteristic (ROC) analyses assessed the relations between levels of harm avoidance (HA) and generalized anxiety disorder (GAD) diagnoses in 334 children and their parents. Analyses revealed HA scores to be highly predictive of GAD diagnoses in children (AUC=.791, P<.001) and adults (AUC=.818, P<.001). However, there were many individuals with high HA scores who did not qualify for a GAD diagnosis. These findings suggest that while there are strong associations between HA and GAD, high levels of HA are neither necessary nor sufficient in the formation of clinically significant anxiety symptoms.