序贯疗法根除幽门螺杆菌

幽门螺旋杆菌（HP）感染是胃炎、消化性溃疡、胃癌和胃黏膜相关淋巴组织淋巴瘤的主要病因,根除HP具有重大的临床意义。随着抗生素耐药株HP逐年增加,HP根除率日益下降,因此出现了一种新的HP根除方案——10天或14天序贯疗法。此疗法指前5天或7天的诱导期中应用质子泵抑制剂（PPI）加一种抗生素的二联治疗,随后5天或7天应用PPI和两种抗生素的三联治疗。目前除少数研究外,绝大多数临床研究表明序贯疗法能够获得比传统的7天或10天三联疗法更高的HP根除率,其具体机制尚不明确。目前大部分相关的研究为单中心、样本量少,缺乏双盲对照,未能评估抗生素耐药性,尚待大样本、多中心、随机双盲对照的临床研究来进一步证实该疗法的有效性和安全性。     

内质网应激和胰岛素抵抗

2型糖尿病的发病机制主要涉及胰岛素抵抗.近年来研究表明内质网应激可诱导胰岛素抵抗的形成,并使与改善胰岛素受体敏感性相关的内质网应激标志物分子氧调节蛋白150和转录因子X盒结合蛋白-1表达增强,表明内质网应激对细胞具有双重作用,一方面可诱导胰岛素抵抗,另一方面激发对应激的适应反应.     

Imaginability,morality, and fictional truth: dissolving the puzzle of ‘imaginative resistance’

This paper argues that there is no genuine puzzle of ‘imaginative resistance’. In part 1 of the paper I argue that the imaginability of fictional propositions is relative to a range of different factors including the ‘thickness’ of certain concepts, and certain pre-theoretical and theoretical commitments. I suggest that those holding realist moral commitments may be more susceptible to resistance and inability than those holding non-realist commitments, and that it is such realist commitments that ultimately motivate the problem. However, I argue that the relativity of imaginability is not a particularly puzzling feature of imagination. In part 2, I claim that it is the so-called ‘alethic’ puzzle, concerning fictional truth, which generates a real puzzle about imaginative resistance. However, I argue that the alethic puzzle itself depends on certain realist assumptions about the nature of fictional truth which are implausible and should be rejected in favour of an interpretive view of fictional truth. Once this is done, I contend, it becomes evident that the supposed problem of imaginative resistance as it has hitherto been discussed in the literature is not puzzling at all.

On the relation between preference and resistance to change

Nevin (1979) noted that preference in concurrent chains and resistance to change in multiple schedules were correlated, in that both measures were affected similarly by variations in parameters of reinforcement such as rate, immediacy, and magnitude. To investigate the relationship between preference and resistance to change directly, we used a within-session procedure that arranged concurrent chains in one half of the session and a multiple schedule in the other half. The same variable-interval schedules served as terminal links in concurrent chains and as the components of the multiple schedule, and were signaled by the same stimuli. After performances had stabilized, responding in the multiple schedule was disrupted by delivering response-independent reinforcement during the blackout periods between components. Both preference in concurrent chains and relative resistance to change of multiple-schedule responding were well described as power functions of relative reinforcement rate, as predicted by current quantitative models (Grace, 1994; Nevin, 1992b). In addition, unsystematic variation in preference and resistance to change was positively correlated, which suggests that preference and resistance to change are independent measures of a single construct. That construct could be described as the learning that occurs regarding the prevailing conditions of reinforcement in a distinctive stimulus situation.     

Small Acts of Living: Everyday Resistance to Violence and Other Forms of Oppression

The author describes an approach to therapy which is based on the observation that whenever persons are badly treated, they resist. Case illustrations are given in which individuals seeking therapy had been subjected to violence and oppression.     

A KANTIAN PERSPECTIVE ON POLITICAL VIOLENCE

Rejecting Kant's absolute opposition to revolution, I propose a modified Kantian perspective for reflecting on political violence, drawing from Kant's basic ideas but abandoning some dubious assumptions. Developing suggestions in earlier papers, the essay sketches a model for moral legislation that combines the core ideas of each of Kant's formulas of the Categorical Imperative. Though only a framework for deliberation, not a complete decision procedure, this excludes extremist positions, prohibitive and permissive, about political violence. Despite Kant's hopes, the values implicit in his fundamental principle fail to support easy, inflexible solutions; but they place strong presumptions against lawless coercion and killing, undermining social order, treating persons as dispensable, underestimating options, arrogant faith in one's own judgment, and reckless simplicity in political thinking.     

EFFECTS OF REINFORCER QUALITY ON BEHAVIORAL MOMENTUM: COORDINATED APPLIED AND BASIC RESEARCH

The high-probability (high-p) instructional sequence has been an effective treatment for noncompliance. However, treatment failures have also been reported. We hypothesized that the efficacy of the high-p treatment may be improved by using higher quality reinforcers for compliance to high-p instructions. The resistance of compliance to change was tested by varying reinforcer quality in two applied studies and a basic laboratory experiment. Experiment 1 tested the hypothesis that an increase in reinforcer quality for high-p compliance will increase the effectiveness of the high-p treatment when it fails to increase compliance. Experiment 2 assessed the effects of reinforcer quality on resistance of compliance to change by presenting successive low-p requests following the high-p treatment. A basic laboratory study (Experiment 3) was conducted to further isolate the relation between reinforcer quality and behavioral momentum. Two different liquid reinforcers (sucrose and citric acid solutions) were presented in a two-component multiple variable-interval variable-interval schedule followed by a single extinction test session. Results of all three experiments showed a generally consistent relationship between reinforcer quality and behavioral momentum.     

Behavioral momentum in college basketball

Three classes of events were scored from videotapes of 14 college basketball games during the 1989 National Collegiate Athletic Association tournament: reinforcers (such as points and favorable turnovers), adversities (such as missed shots, unfavorable turnovers, and fouls), and responses to adversities (favorable or unfavorable outcomes of the first possession of the ball following an adversity). Within-game and within-team analyses of these data supported three findings. First, a team's favorable response to an adversity generally increased as the rate of reinforcement increased 3 min preceding the adversity. Second, basketball coaches called time-out from play when being outscored by their opponents an average of 2.63 to 1.0. Third, calling time-outs from play appeared to be an effective intervention for reducing an opponent's rate of reinforcement. Rates of reinforcement during the 3 min immediately after a time-out were nearly equal for both teams. Results are discussed within a behavioral momentum framework.     

Reductions in shock frequency and response effort as factors in reinforcement by timeout from avoidance

Rats' presses on one lever canceled shocks programmed after variable cycles, while presses on a second lever occasionally produced a 2-min timout during which the shock-delection schedule was suspended and its correlated stimuli removed. These concurrent schedules of avoidance and timeout were embedded in a multiple schedule whose components differed, within and across conditions, in terms of the programmed shock rate associated with the shock-deletion schedule. Analyses based on the generalized matching law suggest that the reduction in the response requirement correlated with termination of the avoidance schedule was a more important factor in the reinforcing effectiveness of timeout than was shock-frequency reduction, at least in 2 of 3 rats. After training in each condition, responding on the timeout lever was extinguished by withholding timeouts in both components over seven sessions. Resistance to extinction varied directly with the rates of both shock-frequency reduction and avoidance-response reduction experienced during training. Although reduction in response effort appeared to dominate shock-frequency reduction in the maintenance of responding, neither factor had a clear advantage in predicting the course of extinction.     

An integrative model for the study of behavioral momentum.

Behavioral momentum is the product of response rate and resistance to change. The data on relative resistance to change are summarized for pigeons responding on single-key two-component multiple schedules, in the initial links of two-key multiple chained schedules, and in equivalent components of two-key serial schedules. For single-key procedures, the ratio of resistance to change in two schedule components is shown to depend on the ratio of reinforcer rates obtained in the presence of the component stimuli. For two-key procedures, the ratio of resistance to change in equivalent components is shown to depend on the ratio of reinforcer rates correlated with key locations. A model based on stimulus-reinforcer contingencies that combines the reinforcer rates in schedule components summed over key locations and reinforcer rates correlated with key locations summed over components, each expressed relative to the session average reinforcer rate, gives a good account of the data. An extension of the relative law of effect for multiple schedules fails to provide a complete account of resistance to change, but both approaches are needed for a comprehensive understanding of behavioral momentum.