Objective To investigate the prevalence of visual fatigue among Chinese college students with the usage of electronic products.Methods A total of 6000 college students were recruited from 127 universities in 29 cities (except Taiwan,Qinghai,Tibet,Ningxia and Xinjiang).The questionnaire involved questions pertaining to the dependence of electronic products,use of electronic products in dormitory,home,vehicles,and prevalence of visual fatigue.Logistic regression was performed to analyze the potential risk factors for visual fatigue.Results A total of 4848 questionnaires were valid,involving 2259 male and 2589 female students.The results revealed that the incidence of visual fatigue in Chinese college students was 53.5％,a higher rate in females than in males.And 33.8％ of whole group admitted that they had become relied on electronic products.The proportion of electronic products used at the table,on the bed,transport equipment reached 91.3％,87.6％ and 74.8％,respectively.In terms of the usage duration,38.3％ of surveyed students use mobile phone,Tablet PC over 4 hours per day,with 29.7％ using electronic products over 1 hour on the bed and 49.1％ in vehicles over 0.5 hour.Univariate logistic regression analysis showed that the prevalence of visual fatigue were related to gender,dependence on electronic products,the use of electronic products in dormitory,home,vehicles.Conclusion The prevalence of visual fatigue is relatively high among Chinese college students,which may be associated with the following several factors,including gender,dependence on electronic products and the use of electronic products in dormitory,home and vehicles.

Objective To investigate the effect of prophylactic administration of atropine before carotid angioplasty and stenting (CAS) on the happening of intraoperative and postoperative hypotension,bradycardia or cardiovascular complications. Methods Seventy-seven patients with carotid atherosclerosis, admitted to our hospital from November 2008 to May 2010 and performed CAS, were chosen in the study. Prophylactic administration of atropine before CAS was performed on 42 patients and the other 35 without atropine administration were adopted as control group. The clinical data of these patients were analyzed and the high risk factors of cardiovascular events (hypotension or bradycardia) at the perioperative period were observed. The incidence of cardiovascular complications at the perioperative period was also recorded and compared. Results No significant differences on the clinical data, high risk factors of cardiovascular events and morphological characteristics of the vessels were noted between the 2 groups (P＞0.05). The operation procedures were almost the same between the 2 groups. As compared with the control group, the atropine treatment group enjoyed significantly lower incidences of intraoperative or perioperative bradycardia and cardiovascular complications at the perioperative period (P＜0.05). Conclusion The prophylactic administration of atropine before CAS decreases the incidence ofbradycardia and cardiovascular complications during and after CAS.

Objective To explore the changes and influencing factors of cerebral vasoreactivity (CVR) in patients after carotid angioplasty and stenting (CAS). Methods Thirty-seven patients performed CAS, admitted to our hospital from July 2008 to September 2009, were finished the follow-up and chosen in our study; the breath-holding index (BHI) of the bilateral middle cerebral artery was measured using transcranial Doppler combined with breath holding test before thc operation, and 1 d and 3-10 months after the operation. Repeated measures design analysis of variance was employed to detect the BHI changes before and after the stenting; multiple regression was employed to analyze the influencing factors of BHI. Results BHI values after stenting were significantly higher than those before stenting on the stenotic side (P＜0.05). The follow-up BHI values were negatively correlated with those of tandem stenoses (β=-0.016, P=0.002) and positively correlated with the postoperative BHI values (β=1.030, P=0.000). Conclusion CAS can immediately improve CVR on the ipsilateral side and make it close to normalization gradually. Tandem stenoses are the independent risk factors of CVR.

Objective To investigate the clinical and neuroimaging features of cerebral microbleeds(CMBs)in patients with ischemic stroke. Methods MRI,including gradient-echo T2~*-weighted MRI,was performed in 85 patients with acute ischemic stroke.Their clinical information and imaging characteristics were analyzed. Results One hundred and twenty-four CMBs were noted in 26 patients(30.6%)with the number of CMBs ranged from 1 to 16 per patient.CMBs were more frequently presentcd in the cortical-subcortical region and thalamus-basal ganglia than in the cerebellum and brain stem legions.Some CMBs in the brain stem had related neurological symptoms and signs.CMBs,the age of the patient,the number of lacunar infarcts and the white matter changes were correlative(r=0.243,P=0.025;r=0.337,P=0.025;r=0.438,P=0.000).CMBs could be well demonstrated in the gradient-echo T2~*-weighted MRI and some larger ones could be demonstrated in the apin-echo T2~*-weighted MRI and DWI. Conclusion CMBs are the sighs for microangiopathy in the brain with advanced age,mutiple lacunar infartion and leukoaraiosis as its main prognosis factors.

Objective To establish the spatial course of distal tubule and afferent arterioles after macula densa, and to locate and detect the proteins in the adjacent parts by using three-dimensional visualization technology of microstructure. Methods C57 BL/6J mice were fixed by perfusion and embedded in epon 812. Tissue blocks were cut perpendicular to the longitudinal axis of the kidney. And a total of 720, 2. 5 μm-thick consecutive sections were obtained from the renal capsule to the outer stripe of the renal outer medulla. After aligning the digital microscopic images through computer registration procedures, the tubules and vessels were traced by 3D reconstruction program edited by C Language. Selecting the tissue sections of the contact site and applying the improved immunoperoxidase staining method to detect H

Objective To describe quantitatively the development of the capillary loop stage glomerulus (capG) with respect to the volume density of capillaries in the glomerulus based on the morphogenesis of the kidney. Methods The kidneys were obtained from mice at various developing time points and prepared for paraffin sections. The volume density of CD34 positive endothelial cells and surrounded capillary lumen in glomeruli was measured using a combination of immunohistochemical staining and the stereological grid system. Results The capG was divided into early, middle, and late phases, and middle phase capG was subdivided into early-middle and late-middle phases, according to the morphology of developing glomeruli and the arrangement of podocytes. As result, the volume density of capillary loops in early phase capG could not be measured due to the complex "glomerular" shape. The volume density of capillary loops increased from (35.95±6.45)% in the early-middle phase capG, to (58.36±6. 30) % in the late-middle phase capG, and to (79.89± 5.21) % in the late phase capG, compared to (93.61 ±1.96) % in the mature glomerulus. Furthermore, the volume density of capillary loops remained constant at same stage even though at different developmental time points. Conclusion This study demonstrated a significantly increased volume density of capillary loops with the kidney development. In addition, the results provide a descriptive and reliable parameter for the evaluation of glomerular development.