OBJECTIVETo establish the method of high-performance liquid chromatography (HPLC) for the determination of N-isopropylaniline in workplace air.

METHODSN-isopropylaniline in the air was collected by silicone tube, and was then dissolved by acetonitrile and determined by HPLC-UV detector.

RESULTSThere was a linear relationship within the range of 0.0-100.0 µg/ml with the method, and the regression equation was y=22 863x+10 665(r=0.999 9); the detection limit was 0.005 µg/ml, and the minimum detectable concentration was 1.7x10(-3) mg/m3 (3.0 L sampling volume); the average recoveries of standard addition were 96.2%-101.3%. The within-run precision was 2.31%-2.99%, and the between-run precision was 3.21%-4.55%. The average desorption efficiency was 97.6%, the breakthrough volume was more than 8.12 mg, the sampling efficiency waE 100%, and the samples could be stored for at least 7 days at room temperature.

CONCLUSIONThe indicators ol the method all meet the requirements of GBZ/T 210.4-2008 (Determination methods of air chemicals in workplace), and can be used for the determination of N-isopropylaniline in workplace air.

BACKGROUND: To search for an alloxenogeneic bone with good load bearing function and osteoblastic activity for treating bone defects is an important study issue. We have made a comparative study on its biome chanical characteristics and found that there was no significant difference in maximum load stress, maximum pressure as compared with fresh bone of the same size. Clinicians are concerned about the osteoblastic activity and whether the osteoblastic activity can be reserved after human allogenous a cellular bone (HAB) loaded with bone marrow stromal cells (BMSCs). OBJECTIVE: To investigate the experimental effect of HAB loaded with induced BMSCs, and observe the cellular adherence and growth as well as detect its osteoblastic activity. DESIGN: Single sample experiment. SETTING: Second Affiliated Hospital of Harbin Medical University. MATERIALS: This experiment was conducted at the Experimental Center of the Second Affiliated Hospital of Harbin Medical University between January 2003 and August 2004. HAB was obtained from fresh corpse iliac bones (donated voluntarily). METHODS: Connective tissues and cell compounds of the iliac bones were removed by processing with hydroperoxide andether solution and sterilized for preparing HAB. BMSCs from living femoral shaft bone marrow were cultured immediately in ordinary and mineralized medium containing DMEM, fetal bovine serum, dexomethasone, β-glycerophophate and ascor bic acid. Proliferation and differentiation of bone stromal cells were deter mined by detecting the level of alkaline phosphatase (ALP) and osteocalcin (OCN) in the culture medium. Induced bone stromal cells solution was condensed and implanted within HAB scaffold. Cellular osteoblastic activ ity was determined through morphological observation under the light mi croscope and electron microscope as well as biochemical index detection. MAIN OUTCOME MEASURES: ① Detection results of ALP and OCN of BMSCs/HAB composite. ② Histological observation results of BMSCs/ HAB composite. RESULTS: ① Iliac bone block cells were cleaned with good reservation of bone matrix. ② The level of ALP and OCN of MSCs was higher after in ducing for 8 days than that in control group [MSCs after induction: (181.54±40.01) nkat/L, (7.2±1.3) μg/L. There was no method to detect the level in control group, P ＜ 0.05]. ③ BMSCs were adhered and grew well in HAB scaffold. CONCLUSION: HAB loaded with induced BMSCs has an excellent os teogenic function in vitro and shows an effective potential as a good bone tissue engineering material.

Objective To investigate the relationship between white matter lesions(WML) and cognitive impairment in migraine with and without aura.Methods 56 migraine without aura patients (MwoA group),22 migraine with aura patients(MA group) and 30 normal controls were recruited.All of them were performed head MRI examination and were evaluated by operational definitions of ARWMC and Mattis Dementia Ratiing Scale(DRS),and compare among three groups,discuss the relationship between WML and cognitive impairment.Results (1) Compared with control group,the occurrence rate of WML in MA group was significantly higher(40.9％ vs 13.3％,x2=22.74,P＜0.01).The OD-ARWMC score was significantly higher in both MA and MwoA groups((0.73±l.12) vs (0.13±0.35),t=2.76,P＜0.01;(0.36±0.67) vs (0.13±0.35),t=1.75,P＜0.05).Compared with MwoA group,the occurrence rate of WML and the OD-ARWMC score of MA group was significantly higher(t=22.80,P＜0.01;t=1.79,P＜0.05).(2) During the attack period,the DRS total scale and its 5 factors (attention,initiation/perseveration,concept formation,construction and memory) were significantly lower in both MwoA and MA group(P＜0.05 or 0.01) than control group,while the DRS total scale and its two factors (attention,concept formation) of MA group were significantly lower than that of MwoA group (P＜ 0.01).During the intermission period,the concept formation and memory scale in MA group was significantly lower than control group(P＜0.05),only memory factor in MwoA group was significantly lower than control group(P＜0.05),while the initiation/perseveration factor scale of MA group was significantly lower than MwoA group(P＜0.05).(3) There Was a negative correlation between OD-ARWMC scale and the total DRS scale as well as its three factors (attention,concept formation,memory)during attack period in MA group(r=-0.584,P＜0.01;r=-0.465,P＜0.05;r=-0.558,P＜0.01;r=-0.439,P＜0.05).There was a negative correlation between OD-ARWMC scale and the total DRS scale as well as concept formation factor during attack period in MwoA group (r=-0.328,P＜ 0.05;r =-0.276,P＜ 0.05).Conclusion Migraine patients may have white matter lesions and cognitive impairment,especially in MA patients and during attack period.

Objective To evaluate the injury of optic radiation after ischemic stroke with diffusion tensor imaging (DTI). Methods From September, 2014 to September, 2015, twenty-one ischemic stroke inpatients with visual field defects were tested with DTI, and measured the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of both sides in different time. The correlation of FA and ADC to visual field mean defect (MD) in the same time was analyzed. Results The FA of affected sides was lower than that of healthy sides twenty-four hours (t=2.38, P<0.05), one week (t=15.60, P<0.01) and four weeks (t=19.13, P<0.01) after stroke, and the ADC was also lower twenty-four hours (t=10.13, P<0.01) and one week (t=6.06, P<0.01) after stroke. The FA correlated with MD one (r=0.581, P<0.01) and four weeks (r=0.703, P<0.01) after stroke, and the ADC correlated with MD twenty-four hours after stroke (r=0.519, P<0.05). The FA of one (r=0.525, P<0.05) and four weeks (r=0.762, P<0.01) after stroke correlated with MD six months after stroke. Conclusion DTI can be used to evaluate the injury of optic radiation after ischemic stroke.

Objective To investigate any changes in motor functional connectivity in the brains of acute ischemic stroke patients after low frequency electrical stimulation.Methods Twenty-five ischemic stroke patients were given low frequency electrical stimulation in addition to their conventional rehabilitation treatment.Another 20 patients received only conventional treatment as a control group.Resting-state functional magnetic resonance imaging (rs-fMRl)was employed to assess motor function connectivity in the brains of all 45 subjects before and after treatment.Any differences in functional impairment,extremity motor function or ability in the activities of daily living were also recorded before and after treatment.Results In both groups,average scores on the Canadian neurological scale (CNS)and the National Institutes of Health stroke scale (NIHSS) had been reduced significantly after treatment and FuglMeyer assessment (FMA) and modified Barthel index (MBI) scores had significantly increased.The average improvements in terms of FMA and MBI scores were significantly greater in the observation group.Compared with before treatment,the coefficient of functional connectivity of the bilateral motor cortex had decreased significantly after treatment in both groups.In the observation group the changes were significantly correlated with the improvements in FMA scores.Conclusion Neural functional impairment after ischemic stroke can be reduced significantly and extremity motor function and ability in the activities of daily living can be significantly improved by low frequency electrical stimulation.

Objective:To observe the effects of auricular point sticking on pain and anxiety during the latent period of the first stage of labor in primiparas. Methods:Primiparas meeting eligibility criteria were recruited.The participants were randomized into an auricular point group,a placebo group,and a control group.The control group received daily care.The auricular point group received 120 min of auricular point sticking therapy.The placebo group received the same auricular plasters as the auricular point group but without pressing.Participants'pain,anxiety,and uterine contractions were measured at enrollment and 30,60,and 120 min of interventions. Results:Data from 78 participants were analyzed in this study.After uterine contraction was adjusted as a covariate,there was no significant difference among groups in the baseline anxiety,baseline pain,and anxiety at 30-min intervention(P>0.05),and no significant difference between the placebo group and the control group in each indicator at each time point(P>0.05).The anxiety scores of the auricular point group at 60 min and 120 min were lower than those of the placebo group and the control group(P<0.05).The pain in the auricular point group was less than that in the placebo group and the control group at 30,60,and 120 min of interventions(P<0.05). Conclusion:Auricular point sticking therapy can relieve anxiety and pain in women during the latent period of labor.Moreover,the effect is fast-acting.It can be used as a safe and effective complementary therapy.

Objective To investigate the relationship between the cerebral microbleeds (CMBs) and changes of cognitive function,and the possible mechanism of cognitive impairment caused by CMBs.Methods Sixty-eight micro-hemorrhage patients on susceptibility weighted imagine (SWI) sequences composed positive group,and sixty-eight patients selected without micro-hemorrhage in the SWI sequence and meeting the selection criteria as control group.At the same time,both two groups were assessed by MoCA and CDT scale inspection.Results CDT scores of CMBs group (2.00±0.88) were significantly lower than those of control group (3.76±0.53),and there was significantly different in the two groups (t=-3.27,P=0.00).At the same time,MoCA total scores and executive functions,naming,calculation,language,abstraction,recall scores of CMBs group were significantly lower than those of control group,and all of the groups were significantly different (t=-5.48,P=0.00; t=-4.36,P=0.00; t=-2.35,P=0.01 ; t=-2.49,P=0.02; t=-4.09,P=0.00; t=-4.63,P=0.00).CDT scores,MoCA total scores,executive functions,language,abstraction,memory scores between CMBs groups and control group were significantly different at all levels (P＜0.05).Executive functions,languages and calculated inter-group of mild CMBs,moderate CMBs,severe CMBs were significantly different (P＜0.05).The number of CMBs was negative correlation with total scores,executive function,language,and abstract (r=-0.675,P=0.000; r=-0.689,P=0.000; r=-0.536,P=0.000; r=-0.636,P=0.000).Conclusion The existence of CMBs and the number of CMBs are closely related to cognitive dysfunction.The more of CMBs,the more of obvious cognitive impairment.

Objective To investigate the alteration and possible compensation mechanism of the default mode network (DMN) in patients with subacute pontine infarction.Methods Rs-fMRI data were collected from 23 patients with subacute pontine infarction and 23 normal controls.The data was analyzed with the functional connectivity (FC) method and compared between subacute pontine infarction patients and controls.All imaging was performed on a Philips Achieva 3.0T MRI scanner.Posterior cingulated cortox (PCC) was used as seed points to analyze the FC changes in the brain regions between the pontine infarction group and the controls.The discrepancies of experiment data between two groups were compared by using two-sample t-test analysis.Results The FC of the DMN showed a significant increase in the right postcentral gyrus, left medial prefrontal cortex and left precuneus compared with normal controls and a significant decrease in bilateral insula,posterior lobe of the left cerebellum,right parahippocampal gyrus and left inferior occipital gyrus.Conclusion The DMN altered in patients with subacute pontine infarction and the changes of the FC suggested the plasticity of cortical or compensation in the relevant brain areas.

ObjectiveTo detect the fiber structure and volume differences in frontal lobe between patients with amnestic mild cognitive impairment (aMCI) and normal control.MethodsT1 -weighted magnetic resonance imaging and diffusion tensor imaging were obtained in 28 aMCI patients and 25 normal controls.Volumes,fiber fractional anisotropy (FA),fiber apparent diffusion coefficient (ADC),fiber number,and average fiber length of frontal lobe in the two groups were measured.ResultsVolumes of left frontal lobe ( ( 337.35 ± 20.45 ) cm3 ) in aMCI group were smaller than control ( (358.54 ± 27.26) cm3 ) ( t =- 3.223,P =0.002 ).Numbers of short range fiber in left frontal lobe ( 16985 ± 892) were significantly increased relative to control ( 16387 ±752) ; while numbers of long range fiber (3214 ± 185 ) were reduced compared with control (3425 ± 277 ),and ADC values increased ( t =2.621,P =0.012; t =-3.714,P =0.001 ; t =17.595,P=0.000).In aM CI group,numbers of long range fiber in right frontal lobe were reduced (2895 ± 343 vs.3451 -± 230,t =- 7.011,P =0.000),and ADC values were increased ( t =4.443,P =0.000).In aMCI group,numbers of long range fiber in left frontal lobe were positively correlated with scores of mini-mental state examination ( MMSE ) ( r =0.457,P =0.015 ),while ADC values of long range fiber in left frontal lobe were negatively correlated with scores of MMSE ( r=-0.415,P=0.028).ConclusionThe structure and fiber connectivity are affected in aMCI patients and the lesion of connectivity in left frontal lobe are related to the severity of symptom.

Objective To investigate the effect and safety of dexmedetomidine combined with dorsal penile nerve block for circumcision in children .Methods 130 children with circumcision were divided into the observation group and the control group according to the digital table ,65 cases in each group .The control group received total inhalation of seven halothane anesthesia ,and the observation group received dexmedetomidine combined with dorsal penile nerve block anesthesia .The efficacy and safety of the two groups were compared .Results In the observation group after induction,the mean arterial pressure[(69.89 ±5.24)mmHg],awake and mean arterial pressure[(70.14 ± 5.30)mmHg],rhythm of the heart after induction [(100.36 ±10.67)times/min],the rhythm of the heart when they woke up[(102.64 ±10.58) times/min],blood oxygen saturation after induction [(98.25 ±0.63)％],awake and blood oxygen saturation[(98.64 ±0.66)％]and other signs of vital signs had no statistically significant differences compared with the control group (F=0.130,0.215,0.548,0.613,0.106,0.257,all P>0.05).In the observation group,the eyelash reflex disappearing time , operation time, awakening time were ( 23.16 ±2.13 ) s, ( 9.70 ± 1.24)min,(10.03 ±1.27)min,respectively,which in the control group were(27.98 ±3.87)s,(11.88 ±2.87)min, (11.89 ±3.87) min,respectively,there were statistically significant differences between the two groups ( t=8.797, 5.621,6.633,all P<0.05).In the observation group,the postoperative agitation score ,sedation score,pain score were(2.75 ±1.25)points,(1.11 ±0.13)points,(5.26 ±1.44)points,respectively,which in the control group were (6.78 ±2.89) points,(1.11 ±0.13) points,(8.97 ±3.64) points,respectively,there were statistically significant differences between the two groups (t =10.318,17.236,10.318,all P <0.05).Conclusion Application of dexmedetomidine combined with penile dorsal nerve block anesthesia in pediatric circumcision takes effect quickly , children with stable vital signs ,less postoperative agitation ,it is worthy of popularization and application in clinic .