A ZnO nanofibers carrier on the Pt electrode via electrospinning technology was prepared and then the Keggin phosphotungstic acid was deposited on the ZnO/Pt electrode using electrodeposition technology. The scanning electron microscopy showed that the zinc oxide fibers presented net structure and the diameter of its fiber was about 300 nanometers. The fourier transform infrared spectroscopy confirmed that the phosphotungstic acid adhered to the fiber surface. The electrochemical property of the modified electrode showed that it exhibited rapid response, excellent sensitivity and good stability, achieving rapid and accurate determination. The electrode responded linearly to ascorbic acid ( AA) in a concentration range from 8. 8 × 10-7 to 3. 3 × 10-4 mol/L with a low detection limit of 2. 5 × 10-7 mol/L. The method is promising for the development of AA detecting instrument.

Background It is widely appreciated that many animal cells rely on the mechanism of regulatory volume decrease (RVD) after swell under the hypotonic environment,which involved in some processes of cellular physiology.But the RVD of lens epithelial cells(LECs) still is being further researched.Objective Present study was to clarify the possible mechanisms and influencing factors in the RVD of LECs.Methods Human LECs line (HLE B-3)were cultured and passaged in DMEM/F12 containing 10％ fetal bovine serum(FBS),and before volume measurement,cells were stuck to the base of a perfusion chamber,Ringer solution osmolality was decreased from 15％Hypo to 45％ Hypo,and the cells stimulated by 45％ Hypo Ringer solution were used as the control group.Some experiments were performed in the presence of high extracellular K+ concentration,chloride or potassium channel inhibitor,experiments were also carried out in the nominal absence of Ca2+,Cl-or HCO-3 to test the effect of a decrease in intracellular concentration of these ions on the cell volume response.The volume changes of living cells were measured by lag-time microphotograph acquisition and analysis system (IPP6.0).Results Time course of cell volume change after hypotonic shock in HLE B-3 cells was observed.The cell swelling was followed by a gradual volume recovery,indicating the presence of RVD was influenced by the hypotonic stress.Under the stimulation of 45 ％Hypo Ringer solution,the rates of RVD were (59.1 ±7.8)％.RVD was correlated positively to the maximum cell volume (r =0.99,P＜0.05)in S shape,and RVD changes were sensitive to alter maximum cell volume in the range of 115％-135％.RVD reduced to (16.5 ± 1.6) ％,(14.7 ± 2.3) ％,respectively after acted by potassium channel inhibitor,TEA(10 mmol/L)and BaCl2(5 mmol/L)as well as chloride channel inhibitor,NPPB(100 μmol/L)and DIDS(100 μmol/L),with significant differences in comparison with the control group(all P＜0.01).RVD decreased by(5.8±1.6)％ and(2.7±0.8)％ in high concentration of K+ in extracellular fluid and the absence of Cl-(P＜0.01).RVD was significantly inhibited under the absence of Ca2+.When the 45％ Ringer solution was pH6.8,the process of RVD delayed.The rate of RVD in the first ten minutes was (0.86±0.24)％/min,showing a significant decline in comparison with (3.24±0.84) ％ / min of pH 7.4 (P ＜0.05).Conclusions HLE B-3 have RVD ability under the hypotonic stress stimulation.A certain intracellular Ca2+ concentration is the premise of RVD activation,and Cl efflux and K+ efflux are the key mechanism of RVD of HLE B-3.Acidic environment of hypotonic solution delays the occurrence of RVD.

To compare the adjuvant therapeutic effect of silicone oil and ointment applied to the lacrimal laser angioplasty.METHODS: Totally, 134 eyes of 102 cases who were diagnosed as lacrimal duct obstruction ( except chronic dacryocystitis) were divided into two groups. Sixty eyes were performed laser plastic operation and silicone oil filling. Seventy - four eyes were adopted laser plastic operation with cloth enzyme dexamethasone eye ointment filling. All patients were followed up for 3 ~ 15mo. The clinical effect and the number of irrigation of two groups were compared 3mo after treatment, and to assess the merits of the method.RESULTS: The efficiency of the silicone oil group was 87% and that of the eye ointment group was 84%. There was no statistically significant difference (P>0. 05). The number of lacrimal duct flushing of the silicone oil group was 7. 20±1. 22 times among postoperative 3mo, and that of the eye ointment group was 7. 96 ± 1. 79 times. The number of lacrimal duct exploration through of the silicone oil group was 0. 62 ± 0. 87 times, that of the eye ointment group was 1. 43 ± 1. 48 times. There was statistically significant differences compared between the two groups (both P<0. 05).CONCLUSlON:The effect of laser plastic operation and silicone oil filling treating obstructive diseases of lacrimal duct is similar to laser plastic operation with cloth enzyme dexamethasone eye ointment, but the postoperative care of the former is more simple. Patients can significantly reduce the frequency of lacrimal duct flushing and lacrimal duct exploration through.

Objective To study the effects of levodopa on the serum excitatory amino acids and some anti oxidative indexes in rats with parkinsonism.Methods Different doses of levodopa/benserazide were treated orally for three months in rats with 6 OHDA induced partial or severe injuries of unilateral nigrostriatal pathway. The levels of serum aspartic acid, glutamate and glutamine were measured by high performance liquid chromatography(HPLC). Serum superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase (GSH PX) were detected.Results After the rats were treated with levodopa,the concentration of serum aspartic acid was significantly increased in the severely 6 OHDA lesioned rats ( P

BACKGROUND: Patients with Alzheimer disease (AD) usually have visuospatial dysfunction at an early stage and most patients with AD were evolved from mild cognitive impairment (MCI).OBJECTIVE: To detect whether a patient with MCI has a visuospatial dysfunction similar to AD. To compare the cerebral activation with ferromagnetic resonance between the healthy people and the patients with mild cognitive disorder.DESIGN: A case controlled observationSETTING: The Department of Neurology of the First Hospital of Peking University.PARTICIPANTS: Nine inpatients with mild cognitive disorder hospitalized at the Department of Neurology of the First Hospital of Peking University from April 2000 to March 2003 were involved and other 9 healthy people matching in age, gender and the educational level were also involved.METHODS: The subjects had the task of discriminating the different finger positions on the clockface. They could see the mission clearly showed on the cloth through refractor, and they were supposed to give the corresponding reaction to different cognitive tasks with left and right hands pressing the keys according to visual sign generated by the computer.Block design was adopted in the cognitive task. Stimulus block and baseline block appeared in turn. Baseline block displayed "+" mapped in the center of the image and was kept for 21s. Stimulus block displayed 10 pictures successively. The finger position of the two clockfaces among three clockfaces was the same in one picture. The absolute value of the rotated angles of the different clockfaces in each image on the same stimulus block was the same. The angles formed by six stimulus block fingers arranged randomly were 300, 450, 1800. The two clockfaces had the same finger positions, and the subjects were requested to discriminate the finger position of these two clockfaces. It was carried out on a 1.5 T GEMRTWIN magnetic resonance scanning apparatus. Then t test was performed to work out the right reaction time and proper rate with Excel software between the patients with mild Alzheimer's disease and the healthy persons. Pretreatment and statistical analyses were performed with analysis of functional neuroimages software used internationally.MAIN OUTCOME MEASURES: Comparison of the reaction time and proper rate between the two groups.parison of the reaction time between the two groups: The reaction time for distinguishing the change of 300, 450, 1800 was longer than that in the control group, and there was significant difference in distinguishing the change of 300, 450, 1800 for the patients [(1 776.7±570.2), (1 646.3±432.7)ms;of the proper rate between the two groups: The proper rate for distinguishing the change of 300, 450, 1800 was significantly lower than that in the control group (62.8±21.4)%, (82.8±15.8)% ;(76.7±17.0)%, (95.0±8.7)%; (69.4vation: the activation density at the bilateral parietal lobe, bilateral temporooccipital borderline and bilateral lateral striate cortex in patients was weaker than that in the control group (P ＜ 0.05).CONCLUSION: Neural network activation related with visual space in patients with MCI was weaker than that in the healthy people indicating that visuospatial impairment exists in the patients with mild cognitive impairment.

Objective To evaluate cystatin C(CysC)in early impairment of renal function in patients of gestational hypertension(GH).Methods Forty patients of GH,70 normotensive pregnant women(35 of early pregnany and 35 of late pregnancy)and 30 normotensive healthy women were enrolled.CysC and ?2-M were measured by particle enhanced nephelometric assay,SCr,BUN and UA were measured by biochemistry analysis.Results The level of CysC in normotensive late pregnancy subjects(1.22?0.19 mg/L)and GH patients(1.93?0.48 mg/L)were higher than that in normal healthy women(0.78?0.22 mg/L,P

Objective To analyze the effect of eukaryotic plasmids containing wild (sense) or anti- sense methylenetetrahydrofolate reductase (MTHFR) gene on cell viability and transcription level of tumor related genes in human gastric cancer cell line.Methods Human gastric cancer cell line MKN-45 was cultured.Recombinant plasmids containing wild MTHFR (W) or antisense MTHFR (A) gene, pCMV-W and pCMV-A,were constructed.Then pCMV-W,pCMV-A and pCMV blank plasmid were transfected into MKN45 cells respectively by using lipofect.Cell viability was analyzed by 3-(4,5-bime- thylthiazolyl-2)-2,5-diphenyhetrazolium dromide(MTT).The transcription levels of Dnmt 1,c-myc, p21~(WAF1) and hMLH1 genes were detected by real-time polymerase chain reaction(PCR).Results Cell vi- ability remarkably increased in those transfected with wild MTHFR (P＜0.01),which was contrary to those transfected with antisense MTHFR(P＜0.01).The expression of those tumor related genes mRNAs were all remarkably decreased in the MKN45-W cells in comparison with those in the MKN45-pCMV cells.No significant difference in the expressions of those tumor related genes mRNAs were found between the MKN45 cells transfected with pCMV-A and blank pCMV.Conclusion MTHFR influences cell viability and the expres- sion level of tumor related genes in human gastric cancer cell line MKN45.

Objective To investigate the correlation between pathologic features and contrast?enhanced ultrasound in patients with breast ductal papilloma. Methods From January 2014 to January 2016,80 patients with breast intraductal tumor treated in our hospital were selected,including 20 cases of breast ductal carcinoma (ductal carcinoma group) and 60 cases of benign tumor (benign group). Both groups received conventional ultrasound, ultrasonic angiography,and pathological feature analysis. Results Breast surrounding hyperecho,internal micro calcification,border edge burr and posterior echo attenuation were more frequently seen onconventional ultrasound in ductal carcinoma groupthan inbenign group(P<0.05). The average scores of contrast?enhanced ultrasound were significantly higher in ductal carcinoma group than in the control group(P<0.05). In the ductal carcinoma group, there were statistical significant differences betweenpatientswith different lymph node metastasis dukes staging ,and differentiation types (P < 0.05). Spearman rank correlation coefficient analysis showed that breast intraductal carcinoma lymph node metastasis and dukes staging,differentiation types were markedly correlated with pathological features and ultrasound imaging (r=0.341,0.368,and-0.289;P<0.05). Conclusions Conventional ultrasound and contrast?enhanced ultrasound have very good imaging featuresin the diagnosis of breast intraductal cancer ,and there is correlation between pathologic features and contrast?enhanced ultrasound in patients with breast ductal papilloma,which can provide values for early diagnosis of breast ductal carcinoma.

Objective To observe the protein expression , subcelluar localization of activated Pak 1 and its relation-ship with chromosome separation during meiosis in mouse oocytes .Methods Western blot was applied to analyze the expression of activated Pak1 (phosphorylated Pak1 at Ser204, pPak1Ser204 ) at different stages of meiotic progres-sion in semi-quantitative manner;immunofluorescent staining was employed to detect the sub-cellular localization of pPak1Ser204 and its spatial-temporal correlation with spindle and microtubule organizing centers (MTOC) during oo-cyte meiosis.Results pPak1Ser204 expression was found upon germinal vesicle breakdown (GVBD) in mouse oo-cytes which increased along with the meiotic progression , reaching peak level at metaphase Ⅰ( MⅠ) , which re-mained up to meiosis Ⅱ(MⅡ).From pro-metaphase Ⅰ(pro-MⅠ) to MⅠand at MⅡstage, pPak1Ser204was co-localized with MTOC key components , pericentrin and γ-tubulin on spindle poles, pPak1Ser204 was also distributed on chromosomes;During anaphase Ⅰ(AⅠ) to telophase Ⅰ(TelⅠ) progression, pPak1Ser204 was detached from chromosomes and MTOC, and mainly concentrated on the cleavage furrow.Conclusions pPak1Ser204 is expressed upon meiotic resumption in oocytes .It is a MTOC-associated protein which may regulate chromosome separation through participating the formation and maintenance of spindle apparatus .

0.05). The contents of striatal dopamine and DOPAC were far more increased in levodopa-treated rats with a high dose than in levodopa-treated rats with a low dose and in saline-treated rats (P