Objective To find out social support status and its influencing factors in left-home-kids in rural areas. Methods 893 left-home-kids and 335 non-left-home-kids were interviewed with the social support rating scale. Results The total score of social support of left-home-kids was obviously lower than that of non-left-home-kids; in the same way, the score of female was higher than male, the score of low age group was higher than high age group, the score of kids with father or mother as the custodian was higher than that of other custodian subjects; the score of children whose left-home duration was more than five years was higher than that of lower than one year. Conclusions The social support of left-home-kids was poorer than non-lefthome-kids. There is some difference in the social support in left-home-kids with different sex, age, custodian subject, left-home duration. Social support should be given to children with low social support.

AIM:Toobservetheeffectsofmicroparticlesderivedfrombonemarrowmesenchymalstemcells ( MSC-MPs) on angiogenesis and cardiac function in a rat myocardial infarction model .METHODS:MSCs were obtained from Sprague-Dawley rats.MSCs were treated under serum-free condition in hypoxia for 72 h, and the microparticles were isolated from the supernatants .The phenotypic profile of MSC-MPs was determined by bead-based flow cytometry and the morphology was observed under a transmission electron microscope .The rat myocardial infarction model was established . The cardiac function was evaluated by echocardiography after the intramyocardial injection of MSC -MPs.The myocardial in-farct size was observed by Masson staining .The blood vessel density in the peri-infarcted area was measured using immuno-histochemical staining for von Willebrand factor and α-smooth muscle actin.The expression of vascular endothelial growth factor ( VEGF) was analyzed by real-time PCR.RESULTS: Apoptotic MSCs released a large quantity of microparticles which were phenotypically similar to the parent MSCs and 100~1 000 nm in diameter.The cardiac functions of myocardial infarction rat model were improved at 7 d and 28 d after intramyocardial injection of MSC-MPs compared with control group . The myocardial infarct size was reduced and angiogenesis was promoted significantly in the infarcted heart injected with MSC-MPs 28 d after treatment .MSC-MPs treatment also increased the expression level of VEGF within 7 d.CONCLU-SION:MSC-MPs protect cardiac tissue from ischemic injury and improve cardiac function by promoting angiogenesis after myocardial infarction .

Unlike conventional imaging technologies, fluorescent imaging benefits from its safety, high-spatial resolution and real-time capability, which make it a highly adoptable imaging method for tumor detection and image-guided surgery in clinics. There are two types of fluorescent probes, including always-on type and environment-responsive type, wherein environment-responsive probes are preferred due to higher target-to-background ratios, which can improve sensitivity and specificity. The environment-responsive probes include enzyme-reactive probes, pH-sensitive probes and hypoxia responsive probes. This review summarizes recent progress in environment-responsive probes, and discusses their potentials in tumor detection and image-guided surgery.