Rapid odor perception in rat olfactory bulb by microelectrode array

Responses of 302 mitral/tufted (M/T) cells in the olfactory bulb were recorded from 42 anesthetized freely breathing rats using a 16-channel microwire electrode array. Saturated vapors of four pure chemicals, anisole, carvone, citral and isoamyl acetate were applied. After aligning spike trains to the initial phase of the inhalation after odor onset, the responses of M/T cells showed transient temporal features including excitatory and inhibitory patterns. Both odor-evoked patterns indicated that mammals recognize odors within a short respiration cycle after odor stimulus. Due to the small amount of information received from a single cell, we pooled results from all responsive M/T cells to study the ensemble activity. The firing rates of the cell ensembles were computed over 100 ms bins and population vectors were constructed. The high dimension vectors were condensed into three dimensions for visualization using principal component analysis. The trajectories of both excitatory and inhibitory cell ensembles displayed strong dynamics during odor stimulation. The distances among cluster centers were enlarged compared to those of the resting state. Thus, we presumed that pictures of odor information sent to higher brain regions were depicted and odor discrimination was completed within the first breathing cycle.     

双液系相图实验中回流时间的摸索

通过对双液系相图回流终点的探索,揭示了回流的规律,提出了实验改进的方法。     

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis

Objective

Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS.

Methods

One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated.

Results

ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of peri-operative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events.

Conclusions

Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival.     

MitraClip: a novel percutaneous approach to mitral valve repair

As life expectancy increases, valvular heart disease is becoming more common. Management of heart disease and primarily valvular heart disease is expected to represent a significant proportion of healthcare provided to the elderly population. Recent years have brought a progression of surgical treatments toward less invasive strategies. This has given rise to percutaneous approaches for the correction of valvular heart disease. Percutaneous mitral valve repair using the MitraClip system (Abbott Vascular, Santa Clara, CA, USA) creates a double orifice and has been successfully used in selected patients with mitral regurgitation. We review the rationale, procedural aspects, and clinical data thus far available for the MitraClip approach to mitral regurgitation.     

我国竞技体育公共服务文化形态及功能作用研究

为了更清楚,全面的表述竞技体育文化的形态与公共服务的关系,主要从竞技体育文形态的物质、体制、精神、意识4个层面说明其具体的表现形式,同时从3个角度分析两者之间的关系：竞技体育具备公共服务的特征;公共服务体系的发展需要竞技体育;竞技体育对公共服务反哺作用。从而进一步加深人们对竞技体育文化的正确认识,营造浓厚的竞技体育文化的氛围,促进竞技体育文化的更好,更快的发展。充分发挥、利用、完善竞技体育对公共服务的文化反哺功效,从而带动整个体育事业的发展,建设体育强国之路。