慢性心房颤动导管消融的若干争议

随着房颤消融技术的迅速发展和提高,阵发性房颤射频消融已列入Ⅰ类推荐,慢性房颤射频消融也列入Ⅱa类适应证.肺静脉电隔离仍是慢性房颤消融的基石.但由于慢性房颤病因不一,机制更加复杂,除了肺静脉电隔离外,还需进行心房基质改良,其消融策略、术式、终点还存在若干争议.     

道德契约论的“启发” ——从高蒂耶的“约束性最大化”谈起

大卫.高蒂耶认为契约论可以把道德构筑在"审慎理性"的基础之上,这一努力因其核心概念"约束性最大化"所隐含的"道德理性"而归于失败。同一理论框架下的双重理性基础使契约论可以从"效用最大化"的视角为规范优先提供某种合情理的说明。这种说明尽管不是一种严密的"证明",却是一种合情理的"启发"。     

An Ecological Understanding of Kinship Foster Care in the United States

We review empirical studies on kinship foster care in the United States. We conceptualize kinship foster care within the context of Urie Bronfenbrenner’s (1994) most recent ecological systems theory. Because there are multiple levels of influences on the developmental outcomes of children placed in kinship foster home, understanding the interrelations between the individual (child) and his or her surrounding environments (e.g., biological families, social-support network) is important. We argue that Bronfenbrenner’s most recent ecological systems theory is an appropriate theoretical framework for policy and practice implications in addressing complex issues surrounding kinship foster care system in the United States. This review integrates the empirical findings collectively on the factors associated with kinship foster care within and between five systems levels of the ecological systems theory: micro- (caregiver-child relationship, attachment, and kinship family environment), meso- (biological families), exo- (social-support network outside the family), macro- (race/ethnicity and policies), and chrono- (welfare reform) systems levels. Theories that are relevant to the ecological factors (e.g., attachment theory) are also discussed. Finally, we draw policy and practice implications from the ecological systems analysis.     

Ursolic acid attenuates lipopolysaccharide-induced cognitive deficits in mouse brain through suppressing p38/NF-κB mediated inflammatory pathways

Evidence indicates that systemic administration of lipopolysaccharide (LPS) induces brain inflammation, ultimately resulting in cognitive deficits. Ursolic acid (UA), a plant-derived pentacyclic triterpenoid, is well known to possess multiple biological functions, including antioxidant, anti-tumor and anti-inflammatory activities. In the present study, we assessed the protective effect of UA against the LPS-induced cognitive deficits in mice. We found that UA significantly improved cognitive deficits of LPS-treated mice in open field, step-through passive avoidance and Morris water maze tasks. One potential mechanism of this action was attributed to the decreased production of pro-inflammatory markers including COX-2, iNOS, TNF-α, IL-1β, IL-2 and IL-6 in LPS-treated mouse brain. Mechanistically, UA markedly inhibited LPS-induced IκBα phosphorylation and degradation, NF-κB p65 nuclear translocation and p38 activation in mouse brain, but did not affect the activation of TLR4, MyD88, ERK, JNK and Akt. Taken together, these results suggest that UA may be useful for mitigating inflammation-associated brain disorders by inhibiting pro-inflammatory factors production, at least in part, through blocking the p38/NF-κB signaling pathways.     

No commonality between attentional capture and attentional blink

Visual search for a unique target is impaired when a salient distractor is presented (attentional capture). This phenomenon is said to occur because attention is diverted to a distractor before it reaches the target. Similarly, perception of the second of two targets embedded in a rapid stream of nontargets is impaired, suggesting attentional deprivation due to the processing of the first target (attentional blink). We examined whether these phenomena emerge from a common underlying attentional mechanism by using correlation studies. If these phenomena share a common foundation, the magnitude of these deficits should show within-subject correlations. Participants (N = 135) revealed significant attentional deficits during spatial and temporal capture and the attentional blink tasks. However, no significant correlation was found among these tasks. Experiment 2 (N = 95) replicated this finding using the same procedure as that used in Experiment 1 but included another attentional blink task that required spatial switching between the two targets. Strong correlations emerged only between the two attentional blink tasks (with/without spatial switching). The present results suggest that attentional deficits during spatial and temporal capture and the attentional blink tasks reflect different aspects of attention.     

Impaired body but not face perception in patients with obsessive–compulsive disorder

Background. Empirical evidence involving the processing of social information by patients with obsessive–compulsive disorder (OCD) has been relatively scarce. Our study investigated the perceptual abilities of patients with OCD to recognize human faces and bodies. Method. Fifty‐four drug‐free or drug‐naïve patients with OCD and 42 healthy controls performed discrimination tasks consisting of four types of stimuli: two sets of faces that were manipulated with regard to configuration and features, human bodies, and chairs. The stimuli were presented in upright and upside‐down orientations. Results. Patients with OCD were significantly less accurate in discriminating pairs of bodily postures implying actions. However, we found no significant differences between patient and control groups in the ability to recognize faces and chairs. The inversion effects for bodies and faces were also comparable between the two groups. Conclusions. The current findings suggest that patients with OCD experience difficulty in perceiving static forms of bodily postures, but are able to adequately recognize human faces. Our data indicate a selective deficit in the perception of bodily postures in those with OCD and suggest that this deficit is probably not related to the abnormal configurational processing of social objects.     

Polymorphism in the CHRNA4 gene is associated with rapid scene categorization performance

The CHRNA4 gene is known to be associated with individual differences in attention. However, its associations with other cognitive functions remain to be elucidated. In the present study, we investigated the effects of genetic variations in CHRNA4 on rapid scene categorization by 100 healthy human participants. In Experiment 1, we also conducted the Attention Network Test (ANT) in order to examine whether the genetic effects could be accounted for by attention. CHRNA4 was genotyped as carrying the TT, CT, or CC allele. The scene categorization task required participants to judge whether the category of a scene image (natural or man-made) was consistent with a cue word displayed at the response phase. The target–mask stimulus onset asynchrony (SOA) ranged from 13 to 93 ms. In comparison with CC-allele carriers, CT- and TT-allele carriers responded more accurately at the long SOA (93 ms) only during natural-scene categorization. In contrast, we observed no consistent association between CHRNA4 and the ANT, and no intertask correlation between scene categorization and the ANT. To validate our natural-scene categorization results, Experiment 2, carried out with an independent sample of 100 participants and a different stimulus set, successfully replicated the association between CHRNA4 genotypes and natural-scene categorization accuracy at long SOAs (67 and 93 ms). Our findings demonstrate, for the first time, that genetic variations in CHRNA4 can moderately contribute to individual differences in natural-scene categorization performance.     

The auditory motion aftereffect: its tuning and specificity in the spatial and frequency domains

In this paper, the auditory motion aftereffect (aMAE) was studied, using real moving sound as both the adapting and the test stimulus. The sound was generated by a loudspeaker mounted on a robot arm that was able to move quietly in three-dimensional space. A total of 7 subjects with normal hearing were tested in three experiments. The results from Experiment 1 showed a robust and reliable negative aMAE in all the subjects. After listening to a sound source moving repeatedly to the right, a stationary sound source was perceived to move to the left. The magnitude of the aMAE tended to increase with adapting velocity up to the highest velocity tested (20 degrees/sec). The aftereffect was largest when the adapting and the test stimuli had similar spatial location and frequency content. Offsetting the locations of the adapting and the test stimuli by 20 degrees reduced the size of the effect by about 50%. A similar decline occurred when the frequency of the adapting and the test stimuli differed by one octave. Our results suggest that the human auditory system possesses specialized mechanisms for detecting auditory motion in the spatial domain.     

门脉高压症治疗观点之辩

对立统一规律是辩证法的实质,在唯物辩证法的理论体系中占有核心地位。门脉高压症的外科治疗有分流术与断流术两种不同的手术方法,这两种方法从治疗机制上看是矛盾的,用对立统一观来认识这两种手术的联系并揭示门脉高压外科治疗发展的哲学依据。     

突破卫生资源宏观调控难关的思考

国务院决定 ,在建立城镇职工医疗保障制度的同时 ,进行医药卫生体制改革 ,以建立适应社会主义市场经济要求的城镇医药卫生体制 ,促进卫生机构和医药行业健康发展 ,提高人民的健康水平[1 ] 。这是进入 2 1世纪我国卫生事业改革与发展面临的历史任务。1　深化改革的关键切入点我国卫生体制改革从 80年代开始 ,首先进行了医疗机构所有制结构调整 ,形成了以公有制为主、多种所有制并存的格局[2 ] ,从而促进了卫生事业的发展。同时 ,卫生事业单位为了适应社会主义市场经济体制 ,也在管理模式、运行机制、经济管理、人事制度等方面 ,采取了多种改…