The incidence of cerebral watershed infarction is higher.At present,the correlation studies of cerebral watershed infarction and cerebral vascular stenosis are mostly limited to the guilty vascular lesions,and the atherosclerotic disease is a chronic systemic inflammatory response.It often exists multiple vascular stenosis.This article elaborates cerebral watershed infarction from the aspects of carotid artery complicated with other parts of the arterial stenosis,middle cerebral artery complicated with other parts of the artery stenosis and collateral circulation in order to improve the awareness of the correlation between watershed cerebral infarction and multiple cerebral artery stenosis.

Objective:To explore the effect of online and offline blended scenario simulation teaching in the practice of nursing undergraduates.Methods:From August 2020 to May 2021, convenience sampling was used to select 76 nursing undergraduates in the class of 2017 who practiced in the Cardiology Department of the Second Affiliated Hospital of Harbin Medical University as the research object. The undergraduates were randomly divided into the experimental group and the control group, 38 in each group. The control group received the traditional graduation practice training, and the experimental group received online and offline blended scenario simulation teaching on this basis. After the practice, the clinical thinking ability of the two groups of students was evaluated by the Clinical Thinking Ability Evaluation Scale, the clinical practice ability of the two groups of students was evaluated by the Objective Structured Clinical Examination (OSCE) , and a teaching satisfaction survey was conducted.Results:The total score of clinical thinking ability, critical thinking ability, systematic thinking ability, evidence-based thinking ability, OSCE total score of the students in the experimental group were higher than those in the control group, and the differences were statistically significant ( P<0.05) . The students in the experimental group thought that the teaching method was helpful for in-depth understanding and application of theoretical knowledge, improving nursing assessment skills, clinical coping skills and communication skills, and at the same time helping to cultivate critical thinking and teamwork awareness, and arouse learning enthusiasm, and the differences were statistically significant (all P<0.05) . Conclusions:The online and offline blended scenario simulation teaching can effectively improve the clinical thinking ability, clinical practice ability and teaching satisfaction of nursing undergraduates, and it has good effect in the graduation practice of undergraduate nursing students.