Objective To observe the head and neck CTA application value in the diagnosis of ischemic cerebrovascular disease.Methods 430 patients with suspected diagnosis of ischemic cerebrovascular disease were adopted with head and neck CTA examination.The carotid artery stenosis degree,grade and plaque formation were observed,and the sensitivity and specificity of CTA in the diagnosis of ischemic cerebrovascular disease were calculated.Results After CTA examination,a tctal of 293 cases (68.14％) with carotid artery stenosis symptoms,among them 87 cases of mild stenosis,moderate stenosis in 169 cases,35 cases of severe stenosis and occlusion in 2 cases.430 plaques were detected in 430 patients,in extracranial arteries,81 soft plaques were identified,as well as 134 calcified plaque and 107 cases of mixed plaque,totally 322 cases;in intracranial arteries 312 cases of the soft plaque were identified,as well as 115 cases of calcified plaque and 97 cases of mixed plaque,totally 524 cases.The sensitivity of CTA in the diagnosis of ischemic cerebrovascular disease was 97.09％ and the specificity was 83.33％.Conclusion In the diagnosis of ischemic cerebrovascular disease,head and neck CTA examination for head and neck vascular stenosis and plaques has visual assessment,and high sensitivity,specificity.

Objective To explore the relationship between vertebrobasilar insufficiencies caused by subclavian steal syndrome and degree or type of steal phenomena.Methods 80 patients who were diagnosed subclavian steal syndrome by transcranial doppler ultrasound were analyzed retrospectively,24 cases in them were received digital subtraction angiography.The degree of steal phenomena were determined by direction of blood flow in the ipsilateral vertebral artery,and the type of steal phenomena were determined by whether basilar artery involved in steal phenomena.Finally,we made the correlation analysis between vertebrobasilar insufficiency caused by subclavian steal syndrome and degree or type of steal phenomena.Results There was a significant relationship between the severity of subclavian artery stenosis and degree of VA steal in 24 patients performed with both TCD and DSA(t =15.59,P ＜0.05).There was no significant relationship between the vertebrobasilar insufficiency and severity of steal phenomena (P ＞0.05).There were 21cases(77.8％) exist vertebrobasilar insufficiency in the patients whose basilar artery were involved in steal phenomena,and there were 18 cases(33.9％) exist ertebrobasilar insufficiency in the patients whose basilar artery were not involved in steal phenomena.There was a significant differences between the two type of steal phenomena(P ＜ 0.05).Conclusion The vertebrobasilar insufficiency caused by subclavian steal syndrome doesn't associate with the degree of steal phenomena,and associates with the type of steal phenomena.Paying close attention to whether basilar arteries are involved in steal phenomena is useful for analyzing the patient 's condition and guide clinical treatment.

ObjectiveTo evaluate the efficacy of intravenous and intra-arterial thrombolysis with urokinase for acute cerebral infarction.Methods Fifty patients with acute cerebral infarction occurred within 6 hours were divided into two groups by random digits table method with 25 cases each:intravenous and intra-arterial thrombolysis group and intravenous thrombolysis group.The patients in intravenous and intra-arterial thrombolysis group were given 200 000 U urokinase by intravenous infusion for 30 minutes immediately after being hospitalized,and arterial thrombolysis was prepared at the same time.With cerebrovascular angiography,the thrombolytic therapy was carried out in the target vessel blocking points through micro-catheter.Urokinase dissolved in 0.9％ sodium chloride was infused at the rate of 10 000 U per minute,the total volume would not be more than 1 000 000 U.The patients in intravenous thrombolysis group were given 1 000 000 U urokinase in 100 ml 0.9％ sodium chloride by intravenous infusion within 60 minutes.The clinical efficacy after thrombolysis was assessed according to the National Institutes of Health stroke scale (NIHSS) score,the quality of life was judged by Barthel index (BI) score and the prognosis was evaluated by modified Rankin scale (mRS) score of 90 days after thrombolysis.ResultsThere was no significant difference between two groups before thrombolysis according to the NIHSS score (P ＞ 0.05).After thrombolysis,NIHSS scores in two groups showed a downward trend,but they were obviously lower in intravenous and intra-arterial thrombolysis group after 24 h,7 d and 14 d than those in intravenous thrombolysis group [(8.97±4.56) scores vs.(11.01±3.65) scores,(6.88±2.31) scores vs.(8.34±3.05) scores,( 4.06±3.02 ) scores vs.( 6.73±2.15 ) scores ] ( P ＜ 0.05 or ＜ 0.01 ).BI scores before thrombolysis between two groups had no significant difference(P ＞0.05),while BI score of 90 days after thrombolysis in intravenous and intra-arterial thrombolysis group [(79.55±19.64) scores] was higher than that in intravenous thrombolysis group [(69.31±21.35) scores](P=0.0162).The rate of mRS score 0-2 (good efficscy) in intravenous and intra-arterial thrombolysis group [72.0％(18/25) ] was obviously higher than that in intravenous thrombolysis group [ 52.0％ ( 13/25 ) ] (P =0.0198 ).ConclusionsIt is significantly effective to treat acute cerebral infarction by superselective intravenous and intra-arterial thrombolysis.Therefore,it is supposed to be an optimal option for treating acute cerebral infarction in the future.

Objective To establish and evaluate a rapid detection method for SARS-CoV-2 based on reverse transcriptase-recombinase aided amplification(RT-RAA)combined with the clustered regularly interspaced short palindromic repeats(CRISPR)/Cas12a system.Methods RT-RAA primers and CRISPR-derived RNA(crRNA)were designed based on the nucleocapsid(N)gene of SARS-CoV-2 from NCBI database.The detection system was optimized with magnesium acetate(MgAc)concentration,RT-RAA reaction tempera-ture and time and LbCas12a reaction temperature.The sensitivity and specificity of the method were evaluated using recombinant plas-mids(100-106 copies/μL)and other respiratory pathogens.The RT-RAA-CRISPR/Cas12a method was compared with RT-PCR by tes-ting 70 clinical samples in parallel.Results The optimized RT-RAA-CRISPR/Cas12a assay could detect SARS-CoV-2 within 50 min at 37 ℃.The limit of detection was 10 copies/μL for the fluorescence-based method and 1×102 copies/μL for the lateral flow assay.The method specifically detected SARS-CoV-2 without cross-reactivity to other respiratory pathogens.The results of testing 70 clinical samples using RT-RAA-CRISPR/Cas12a showed agreement of 100％with those of RT-PCR.Conclusion The established RT-RAA-CRISPR/Cas12a assay for SARS-CoV-2 detection is rapid,cost-effective,highly sensitive and specific.It can be performed by less experienced personnel and no expensive equipment is required,thus it may provide a new approach for rapid clinical diagnosis and large-scale on-site screening of SARS-CoV-2.