与癌共存安享欢乐生活

癌症是现代社会人群意外死亡的致命杀手,目前医学科学还没有完美预防和治疗它的措施和办法,恐惧、悲观、失望、焦虑是有害的,过度治疗也不可取,与癌共存,安享生活是值得提倡的理念。     

成人严重感染与感染性休克血流动力学监测与支持指南(草案)

严重感染(severe sepsis)及其相关的感染性休克(septic shock)和多脏器功能障碍综合征(multiple organ dysfunction syndrome MODS)是当前重症加强治疗病房(ICU)内主要的死亡原因,也是当代重症医学面临的主要焦点及难点[1-2].在美国,每年有75万的严重感染病例发生,超过了充血性心力衰竭或乳腺癌、结肠癌和艾滋病的患病数总和,病死率大概在20%～63%,和急性心肌梗死的院外病死率相近.     

How long do the short‐term violent video game effects last?

How long do the effects of the initial short‐term increase in aggression and physiological arousal last after violent video game play? Study 1 (N=91) had participants complete pre‐ and postvideo game measures of aggressive thoughts, aggressive feelings, and heart rate. Then, participants completed Time 3 measures after 4 min or 9 min of delay. Study 2 employed a similar procedure, but had participants (N=91) complete the hot sauce paradigm to assess aggressive behavior after a 0, 5, or 10 min delay. First, results indicated that aggressive feelings, aggressive thoughts, aggressive behavior, and heart rate initially increased after violent video game play. Second, results of the delay condition revealed that the increase in aggressive feelings and aggressive thoughts lasted less than 4 min, whereas heart rate and aggressive behavior lasted 4–9 min. Aggr. Behav. 35:225–236, 2009. © 2009 Wiley‐Liss, Inc.     

Statistical inference in behavior analysis: Some things significance testing does and does not do

Significance testing plays a prominent role in behavioral science, but its value is frequently overestimated. It does not estimate the reliability of a finding, it does not yield a probability that results are due to chance, nor does it usually answer an important question. In behavioral science it can limit the reasons for doing experiments, reduce scientific responsibility, and emphasize population parameters at the expense of behavior. It can, and usually does, lead to a poor approach to theory testing, and it can also, in behavior-analytic experiments, discount reliability of data. At best, statistical significance is an ancillary aspect of a set of data, and therefore should play a relatively minor role in advancing a science of behavior.     

Signalled and unsignalled percentage reinforcement of performance under a chained schedule

Pigeons were trained to peck a key under a chained fixed-ratio 15 fixed-interval 25-sec schedule of food presentation. In Experiment 1, blocks of sessions in which 100%, 75%, 50%, and 25% of the sequences ended with food presentation were conducted. When food presentation was omitted, a timeout of equal duration replaced it. As the frequency of food presentation decreased so did the frequency of completing the chained schedule. In Experiment 2, 75%, 50%, or 25% of the sequences terminated with food presentation and outcomes were signalled, i.e., completion of the fixed ratio resulted in either a stimulus correlated with the fixed-interval 25-sec schedule or a stimulus correlated with extinction. As the frequency of food presentation decreased, the number of sequences completed per session increased for two pigeons and remained high for a third. In Experiments 3 and 4, assessments of the effects of signalling the outcome of the chained schedule were made with response-independent presentation of events at the end of the sequence. Again, signalling the outcome of the chained schedule led to more chains being completed per session than did not signalling the outcome. Stimuli differentially paired with food presentation have powerful behavioral effects that may be attributed to the potency of these stimuli as conditioned reinforcers.     

Cocaine and food deprivation: effects on food-reinforced fixed-ratio performance in pigeons.

Key pecking by 6 pigeons was maintained by a fixed-ratio 30 schedule of food presentation while body weights were 80% of free-feeding weights. Acute administration of cocaine (0.3 to 13.0 mg/kg, i.m.) dose-dependently decreased response rates. Dose-effect curves were shifted to the right when 3 of the 6 pigeons were maintained at 70% of free-feeding weights and were shifted to the left when the other 3 pigeons were maintained at 90% of free-feeding weights. Then a dose of cocaine that initially decreased response rates by more than 95% of control rates was administered before each daily session. Comparable degrees of tolerance to these rate-decreasing effects developed in the two groups. The rate at which responding recovered was relatively rapid for pigeons in the 70% free-feeding-weight group and was slower for 2 of the 3 pigeons in the 90% free-feeding-weight group. When body weights were then increased from 70% to 80% or were decreased from 90% to 80% of free-feeding weight, performance was disrupted initially only for pigeons whose weight went from 70% to 80% of free feeding. In the present experiment the degree of deprivation may have indirectly influenced the degree of tolerance that developed to cocaine's response rate-decreasing effects because it directly influenced the dose chosen to be administered chronically. The degree of deprivation appeared to have a more direct influence on the rate at which tolerance developed.