Objective To improve the gene targeting efficiency with C57BL/6 embryonic stem ( ES) cells.Meth-ods Three different genetically modified C57BL/6 ES cell lines, named TLX3, Ai3K and SL, were microinjected into ICR, B6( Cg)-Tyrc-2J and BALB/c mouse blastocysts, respectively.The efficiency was statistically evaluated according to three aspects:blastocyst collection, chimera production and germline transmission.Results None of the three ES cell lines was germline transmitted with B6(Cg)-Tyrc-2J mice as blastocyst donors, while it was achieved with both BALB/c and ICR mouse blastocysts.Compared in the aspect of blastocysts collection, ICR mouse was much better than BALB/c mouse (P<0.05), and the chimera production efficiency of ICR mouse was comparable to that of BALB/c mouse (P =0.115). As to the germline transmission efficiency, that of BALB/c mice is significantly higher than that of the ICR mice ( P<0.01).Conclusions The germline transmission efficiency of BALB/c mouse is highest among these three mouse strains. However, it has the disadvantages of blastocyst collection, developmental delay and zona pellucida fragility, compared with ICR mouse.Therefore, ICR mouse is also a good candidate as blastocyst donor for embryonic stem cell microinjection.

Objective To establish a simple , fast and economic total DNA extraction method to serve the rapid identification of model mouse genotype in large number of mice .Methods Three methods, i.e.phenol extraction, isopropyl alcohol precipitation and mouse ear boiling methods were used to extract the total DNA from ten C 57-rasmodel mice.The purity and yield of DNA obtained by the three methods were compared , and polymerase chain reaction ( PCR) assay was used to compare the efficacy of the three extraction methods .Results Among the three methods , phenol extraction was the best and isopropyl alcohol precipitation was the poorest in DNA yield .In terms of DNA purity , the phenol extraction was the best and the mouse ear boiling method was the poorest .All the three methods could be used to extract the total DNA from mice serving as template of PCR reaction for the mouse genotype identification .The time consumption of three methods are 12.5 hr ,13 hr and 0.18 hr.Mouse ear boiling method was significantly lower than that of the other two methods ( P <0.01 ) ,.The obtained total DNA can be stored at conventional -20℃for 7 days and 30 days later still can be used as a template for PCR reaction .Conclusions Among the three methods studied , the mouse ear boiling method is simple and with the lowest cost , so it is feasible for total DNA extraction in scaled genotyping experiments .

Objective To obtain the basic growth parameters of a self-established F1 hybrid CB6F1 C57-ras transgenic mouse model, and to provide basic information for commercialization of this mouse model. Methods F1 hybrid mice (CB6F1) were produced by crossing C57-ras heterozygous transgenic (c-Ha-ras+/-) male mice and wild-type BALB/cJ female mice.The average litter size, weaning rate, sex ratio, growth performance and C57-ras transgenic positive rate were recorded and analyzed.Results The average litter size was eight, weaning rate was 90%, and sex ratio was approximately in accordance with prediction.The average body weight of newborn mice was 1.73 ±0.05 g.The average body weight of 10-week old c-Ha-ras transgenic female and male mice in CB6F1 background was 24.38 ±1.74 g and 29.42 ±1.72g, respectively, which had a significant difference (P<0.01).The c-Ha-ras transgenic positive rate was 46.9%. which was in accordance with genetic rules.Conclusions The F1 hybrid mice (CB6F1) produced by crossing C57-ras heterozygous transgenic ( c-Ha-ras +/-) male mice and wild-type BALB/cJ female mice show normal growth performance and development characteristics, and it can be used for large-scale commercial supply.

Objective:To explore the current situation of turnover intention of male nurses in Shanghai and its influencing factors.Methods:From March 2017 and August 2017, this study selected 349 male nurses at all levels of hospitals in Shanghai by snowball sampling to carry out questionnaire survey through internet questionnaire distribution platform. The questionnaire consisted of the General Demographic Characteristics, Turnover Intention Scale (TIS) , Maslach Burnout Inventory General Survey (MBI-GS) and the Organization Commitment Scale.Results:Among 349 male nurses in Shanghai, the score of turnover intention was (15.43±3.48) , 274 of them were with a high level of turnover intention accounting for 78.49%. There were statistical differences in the scores of turnover intention among male nurses with different positional titles and night shifts ( P<0.05) . Multiple linear regression analysis showed that the important influencing factors of turnover intention of male nurses included the emotional burnout, emotional commitment, ideal commitment and economic commitment, in which the emotional burnout was the strongest predictor and the emotional commitment was the strongest protective factor. Conclusions:The turnover intention of male nurses is in the high level. The important influencing factors of turnover intention of male nurses include the job burnout and organizational commitment except for positional titles and night shifts. Nursing managers should pay attention to the cultivation of emotions for hospital and profession among male nurses so as to reduce male nurses' turnover intention and stabilize the male nursing team.

Ischemic stroke is the leading cause of disability in China,and treatment options are still very limited.The method of dredging Fu-organs has been proved to have a significant effect in the treatment of ischemic stroke,but its mechanism is not clear.With the progress of brain-gut communication research,more and more evidence shows that brain-gut communication plays an important role during ischemic stroke.Based on the theory of"brain-gut interaction",this paper discusses the mechanism of Tongfu method in the treatment of ischemic stroke,and discusses the intestinal flora,brain-gut peptide,intestinal metabolites,intestinal mucosal barrier and other aspects.It is concluded that Tongfu method can treat ischemic stroke by regulating intestinal flora,brain-gut peptide content,intestinal metabolite content and repairing intestinal mucosal barrier.In order to provide more ideas for elucidating the mechanism of Tongfu method in the treatment of ischemic stroke,it has very important theoretical and clinical value.

Cerebral ischemia-reperfusion injury(CIR1)refers to the recovery of blood supply after cerebral ischemia,which leads to further damage and the dysfunction of brain tissue.Modern medicine has made some progress in the prevention and treatment of CIRI,but it still faces some challenges and limitations.Therefore,it is of great clinical value to find effective interventions to prevent and treat CIRI.AMP-activated protein kinase(AMPK)and its downstream proteins are important targets for the treatment of CIRI and play key roles in the regulation of cellular energy homeostasis.Traditional Chinese medicine for CIRI has multi-target and multi-pathway activities and multiple effects.It can activate a cascade of reactions in the AMPK signaling pathway and can be used to treat CIRI by regulating autophagy,oxidative stress,inflammatory response,and apoptosis,and has achieved certain result.Therefore,this paper summarizes the structure and mechanisms of the AMPK-related signaling pathway,elaborates on its relationship with CIRI,and systematically summarizes the research status of traditional Chinese medicine's ability to regulate the AMPK signaling pathway in the prevention and treatment of CIRI.This paper aims to provide new ideas for the prevention and treatment of CIRI using traditional Chinese medicine and the development of new drugs.

Cerebral ischemia reperfusion injury （CIRI） is a secondary brain injury that may occur in patients with ischemic stroke during the process of blood flow recovery. NOD-like receptor protein 3 （NLRP3） inflammasome plays an important role in the occurrence and development of CIRI. Regulating the activity of NLRP3 inflammasome can induce cell pyroptosis， induce neuroinflammatory response， promote macrophage/microglial polarization， destroy the blood-brain barrier， affect angiogenesis and neurogenesis， thereby affecting CIRI. Traditional Chinese medicine has obvious advantages in the treatment of CIRI. In this paper， with NLRP3 inflammasome as the core， we systematically elucidated the mechanism of action of traditional Chinese medicines on CIRI， and found that traditional Chinese medicines monomers （such as baicalin， polygalasaponin F） and traditional Chinese medicines compound formulas （such as Huangqi guizhi wuwu decoction， Yiqi shengqing formulation） can inhibit NLRP3 inflammasome activity， reduce inflammatory response and oxidative stress， and improve neuronal injury， thereby reducing CIRI.

Cerebral ischemia reperfusion injury （CIRI） is a secondary brain injury that may occur in patients with ischemic stroke during the process of blood flow recovery. NOD-like receptor protein 3 （NLRP3） inflammasome plays an important role in the occurrence and development of CIRI. Regulating the activity of NLRP3 inflammasome can induce cell pyroptosis， induce neuroinflammatory response， promote macrophage/microglial polarization， destroy the blood-brain barrier， affect angiogenesis and neurogenesis， thereby affecting CIRI. Traditional Chinese medicine has obvious advantages in the treatment of CIRI. In this paper， with NLRP3 inflammasome as the core， we systematically elucidated the mechanism of action of traditional Chinese medicines on CIRI， and found that traditional Chinese medicines monomers （such as baicalin， polygalasaponin F） and traditional Chinese medicines compound formulas （such as Huangqi guizhi wuwu decoction， Yiqi shengqing formulation） can inhibit NLRP3 inflammasome activity， reduce inflammatory response and oxidative stress， and improve neuronal injury， thereby reducing CIRI.