<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">目的了解6¹8岁视力低常中小学生屈光状态,为防治近视提供依据。方法对1 354例视力低常中小学生睫状肌麻痹电脑验光,采用SPSS 13.0软件进行统计分析。结果视力低常眼2 708只,近视占76.39%,正视占5.21%,远视占18.40%;各年龄组不同性别、眼别平均屈光度比较,差异均有统计学意义;散光检出率为72.27%,远视散光占20.08%,近视散光占75.47%,混合散光占4.45%,&lt;7岁年龄组以远视散光居多,≥8岁各年龄组均以近视散光为主;所有类型散光眼轴向均以顺规散光为主,散光程度以0.50¹.00 DC多见。结论中小学生眼保健已成为重要的公共卫生问题,应加强视力保护工作,促进中小学生身心健康。</span>

Objective To study static refraction condition among elementary and middle school students aged 6-18 years and with below normal vision and to provide basis for myopid prevention.Methods Ciliary muscle paralysis optometry was carreid out among 1 354 elementary and middle school students with refractive defect.The data collected was analyzed with SPSS13.0.Results Totally 2 708 eyes were ascertained with below normal vision with a prevalence of 76.39% for myopia,5.21% for emmetropia,and 18.40% for hyperopia.There were age and gender differences in diopter in the students.The prevaleace of astigmatism was 72.27%,with 20.08% of hypermetropic astigmatism,75.47% of myopic astigmatism,and 4.45% of mixed astigmatism.The hypermetropic astigmatism was prevalent among the students of 7-years-old,and myopic astigmatism was prevalent among students above eight years old.With-the-rule astigmatism accounted for a majority of all types of astigmatism.Most astigmatism degrees were between 0.50 and 1.00 DC.Conclusion Eye care has become an important public health problem for school students and should be strengthened in primary and middle schools.

Objective To study static refraction condition among elementary and middle school students aged 6-18 years and with below normal vision and to provide basis for myopid prevention.Methods Ciliary muscle paralysis optometry was carreid out among 1 354 elementary and middle school students with refractive defect.The data collected was analyzed with SPSS13.0.Results Totally 2 708 eyes were ascertained with below normal vision with a prevalence of 76.39% for myopia,5.21% for emmetropia,and 18.40% for hyperopia.There were age and gender differences in diopter in the students.The prevaleace of astigmatism was 72.27%,with 20.08% of hypermetropic astigmatism,75.47% of myopic astigmatism,and 4.45% of mixed astigmatism.The hypermetropic astigmatism was prevalent among the students of 7-years-old,and myopic astigmatism was prevalent among students above eight years old.With-the-rule astigmatism accounted for a majority of all types of astigmatism.Most astigmatism degrees were between 0.50 and 1.00 DC.Conclusion Eye care has become an important public health problem for school students and should be strengthened in primary and middle schools.

OBJECTIVE To investigate the effect of long-term and low-level occupational Mn exposure on the level of uric acid (UA) in human urine. METHODS In this study, 65 volunteers were recruited, who were working on welding and foundry work in an plant in Gansu province, China. Additionally, 29 control samples were collected from individuals who did not have any history of excessive Mn exposure. An improved high performance liquid chromatography system equipped with a diode-array detector (HPLC-DAD) method was developed to determine the UA level in human urine. A Spectra AA 220 Atomic Absorption Spectrophotometer (AAS) was used to measure the Mn level in the urine. RESULTS The analytical method was validated for concentrations ranging from 3.82-45.84 μg/mL with acceptable accuracy, precision, and recovery. Overall, the UA levels of Mn exposure samples were significantly lower than that of control samples (P<0.05). CONCLUSION The practical method developed here is suitable for both routine monitoring of UA level in human urine and metabolism research. Long-term and low-level occupational Mn exposure may lead to a lower UA level in urine, and UA might be an indicator of the early stage of manganism.

Objective To explore the effect of ambient air pollution on hospital admissions of circulatory system diseases.Methods The data on air pollution index(API),meteorology and the hospitalization of circulatory system diseases from Jan 1st 2004 through Oct 31st 2007 in Lanzhou city were collected.The effect of the ambient air pollution on the health of circulatory system was investigated using generalized additive Poisson models after controlling for the effect of long-term time trend,week and meteorology,and stratified by sex,age and the type of circulatory system diseaseses.Results The every one inter-quartile(48 units) increase in daily API was associated approximately with 1.35% to 3.62% increase of daily hospital admission for circulatory system disease for the delay range from current day to day 5 after the lag effect.The relative risk(RR) reached its highest(1.04226,95% confidence interval=1.02510-1.05881) among males five day after the lag effect.The RR for the females was higher than that of the males only in the four day after the lag effect.From current day to day 5 after the lag effect,the RR level was high than 1.02 for the subjects over 65-years-old.And the RR level by day 2 to day 5 after the lag effect for the subjects of 16 to 64 years old was of statistical significance.Ambient air pollution was more likely to affect hypertension patients and blood vessel of brain disease and the RR level reached its highest(1.07291,95%CI=1.04448-1.10211 and 1.04372,95%CI=1.01432-1.07397) at day 5 after the lag effect.The RR reached its highest(1.02521,95%CI=1.00157-1.04941) among coronary disease day 2 after the lag effect.Conclusion The results show that air pollution considerably affects the circulatory system morbidity among urban residents,and the effects are related to gender,age and the type of circulatory system diseases.

The paper is aimed at presenting our study of the effects of the ambient air pollution on the daily respiratory hospitalization in Lanzhou. The data on the air pollution index (API), along with the relevant data on the meteorological changes and the hospitalization of the respiratory diseases sufferers are all collected based on the city government's bulletin from Jan.1 2004 to Oct.31' 2007 in the areas of City. We have also adopted a generalized additive model (GAM) for Poisson regression for analyzing the effect of ambient air on the daily hospitalization of respiratory disease patients among the city residents, in terms of gender, age and types of the respiratory disease, as well as their ways of using non-parametric smooth functions in controlling long-term trends, cyclical and meteorological factors. The results of our investigation indicate that, for every case of IQR (48 units) increase in daily API, there was a 5.50 (95% CI: 4.03 % , 6.99 % ) increase in the respiratory disease admissions, which has brought a certain long-lasting effect. Statistics also shows that the Relevant Risk ( RR) has reached its highest rate of 1.0583 (95 % CI 1.039 7 - 1.077 2) among the male residents one day after the lag effect, whereas that for female reached its highest when API increased . Except for the day 3 and day 4 after the lag effect, female residents tend to have lower RR level than males. As to the ambient air pollution, it is more likely for the city residents under 15-years-old and over 65-years-old to be affected whereas the RR level reached its highest 1.059 5 (1.040 7 - 1.078 7) and 1.056 0 (1.030 6- 1.082 1) at the third day and the fourth day after the lag effect, respectively . Immediate after the day, when API increased, a number of cases follow in hospitalization of pneumonia and upper respiratory tract infections (URTI), with their RR levels going up to 1.059 5 (1.040 7-1.078 7)and 1.056 0(1.030 6- 1.082 1)respectively. And the lag effect on pneumonia sufferers proves higher than those of upper respiratory tract infection ( URTI) . Thus, our investigation shows that air pollution brings about considerable effect on the morbidity of respiratory diseases among the city residents, though there is a certain level of disparities on those impacts in terms of gender, age and the disease type.

Objective To explore the adverse effects of sandstorm on children's respiratory system.Methods During the sandstorm,students of grades 3-5 were selected in 4 primary schools of Lanzhou and Dunhuang.1 094 students were selected as the subjects in the present study.Questionnaires investigation was conducted the day before the dust storm on April 23,2009 and the followed up investigation of 7 consecutive days was done.Contents of the research included general conditions and respiratory symptoms.Results The number of children with various acute stimulated symptoms increased in various degree on the sandstorm day compared with the day before the dust storm,as for the symptoms such as nasal dryness,runny nose,rhinostegnosis,epistaxis,dryness of the throat,pharyngodynia,cough,bitter mouth,persistent cough,morning cough,serious outdoor cough,productivecough and chest depressing,the differences were significant between the two days(P0.05).The incidence of children's respiratory symptoms decreased gradually after the accident day(1st day to 5th).The results of multiple logistic analysis showed that the children with bronchitis and upper respiratory tract infection before sandstorm were prone to have respiratory diseases after the sandstorm,OR values separately were 1.873,2.239 and 1.595.Conclusion Dust storms can cause acute injury in the respiratory system of children,and the incidence in children with respiratory diseases history is high.

The objective of the research was to explore the impact of air pollution on the health of human respiratory system. The method of the study was to collect data of Air Pollution Index (API), meteorology and the hospitalization of respiratory from 2004 to 2007 in urban of Lanzhou,China. The impact of the air pollution on the health of respiratory was investigated Generalized Additive Poisson models after controlling long-term time trend, week and meteorology, and stratified by gender, age and respiratory disease type. The result of the study is that every one of IQR (48 units) rising in daily API, there was a 5.50 (95%CI: 4.03%, 6.99%) increase in respiratory hospitalizations, and this influence was delayed effects.Males are more susceptible than females to air pollution and air pollution is more likely to affect under 15-years-old and over 65-years-old. As well as the delayed effects of API rising to pneumonia patients is higher than upper respiratory tract infection (URTI). The conclusion of the study is that air pollution considerably affects urban residents' respiratory morbidity, and gender, age and respiratory disease type had different effects.

There is sand-dust pollution problem in the edge of the desert region of China all the time,where several million people many citizens in large cities included are threatened by desert pneumoconiosis.In recent years there are reports of cases of desert pneumoconiosis.The authors of this paper reviewed on the research status of desert Pneumoconiosis at home and abroad,and suggested survey and evaluation of desert pneumoconiosis in northwest of China so as to take effective measures to prevent and control desert pneumoconiosis.

Objective To explore the effect of methyl acrylate (MA) on pneumonocyte injury in mice and to elucidate an immunotoxic mechanism of MA.Methods 40 Kunming mice were randomly divided into 4 groups as follows:normal control group,280 mg/m3,560 mg/m3 and 1 120 mg/m3 MA inhalation group.Mice exposed to different concentrations of MA through static inhalation,2 hours a day for 30 days.24 hours after the last exposure,the mice were executed and the relative weights of lung and heart were calculated.The upper lobe of right lung was taken for routine pathological examination.The contents of IL-6 and TNF-α were measured with enzyme-linked immunosorbent assay (ELISA).Results Compared with the control group,the levels of TNF-α and IL-6 in lung tissue significantly increased except for TNF-α at 280 mg/m3 group (P0.05).Cardiopulmonary index and lung wet/dry weight ratio were not caused statistically increase(P0.05) in all MA inhalation groups.Under the optical microscopy,lung tissue in each concentration group was characterized by an infiltrate of inflammatory cells and hyperaemia.Oedema was observed in the group of 1 120mg/m3.Conclusion Pneumonocyte injury and inflammatory response induced by MA could associate with the changes of TNF-α and IL-6.

PP-30-026 Background/Aims: To study the characteristics of bulk and surface elemental composition of ambient PM2.5 in 5 Chinese cities, which are differently affected by sand-dust events. Methods: Between 16 April and 17 May, 2008, ambient PM2.5 were sampled in sand-dust source terrains (Hotan city) and in sandstorm-affected zones (Korla, Dunhuang, Lanzhou, and Beijing). X-ray photoelectron spectroscopy and x-ray fluorescence were used to analyze surface elemental composition, chemical states, and total elemental composition of PM2.5, respectively. The elemental data were also processed using factor analysis to identify their sources. Results: The surface and bulk elemental composition of ambient PM2.5 among different cities varied significantly. In Beijing and Lanzhou, the percentages of surface elements (carbon-containing compounds, nitrogen-containing compounds, and sulfate), as well as bulk elements (zinc, sulfur, copper, and lead), were much higher than those in the other 3 cities. In Hotan and Korla city, the surface and bulk element contents (sodium, iron, calcium, potassium, chlorine, silicon, aluminum, and magnesium) of PM2.5 were significantly higher than those in Beijing and Lanzhou; zinc, iron, and magnesium were found to be enriched on the surface of PM2.5. Following are the results of factor analysis: Bulk and surface elements such as sodium, iron, calcium, potassium, chlorine, silicon, aluminum, and magnesium came from natural sources, whereas zinc and sulfate came from anthropogenic sources; Surface elements including aliphatic carbon, carbon combined with nitrogen, carbonyl carbon, organic nitrogen, and ammonium salt were anthropogenic pollutants; Of bulk elements, manganese came from natural sources, whereas copper and lead came from anthropogenic pollutants. Conclusion: In the areas that were seriously affected by sandstorm, the bulk and surface elemental composition of PM2.5 had greater proportion of natural sources, whereas in the areas less affected by sandstorm, the elemental compositions had greater proportion of anthropogenic sources.

Objective To study the health effects of the adults exposure to a dust event.Methods Parents of the students in grades 3-5 were selected as the subject in 3 primary schools in Lanzhou and Dunhuang,1 748 adults were selected.The questionnaires investigation was conducted the day before the dust storm and the followed up investigation of 7 consecutive days was done.Contents of the research included general conditions and acute irritation symptoms.Results The number of adults with various acute irritation symptoms increased in various degree on the sandstorm day.Compared with the day before the dust storm,the incidence of symptoms was significantly higher in the dust storm day.As for the symptoms such as dry eyes,ocular foreign body sensation,tearing,photophobia,mycteroxerosis,running nose,nasal congestion,dry itchy throat,pharyngalgia,cough,dry lips,chapped lips,dry skin,skin allergies,skin infection,the differences were significant between the two days(P0.05).Except for tearing,pharyngalgia,skin allergies and skin infection,all the other symptoms rates of male were higher than those of female.Dry eyes,mycteroxerosis,nasal congestion and dry lips rates of male were significantly higher than those of female(P0.05).The incidence of adults'acute stimulated symptoms gradually decreased after the accident day(the 4th).The results of multiple logistic analysis showed that people with smoking,dust conditions,physical discomfort,eye infection,emphysema,asthmatic attack and upper respiratory tract infection before the dust storm were prone to have acute irritation symptoms after the dust storm.Conclusion Sand storms may have acute adverse impacts on adults,and the high incidence exists in male.

Objective To research the toxic effects on manganese chloride(MnCl2) of apoptosis and mitochondrial transmembrane potential of pheochromocytoma (PC12) cells and to reveal the molecular mechanisms of dysfunction caused by manganese.Methods PC12 cells in logarithm period were incubated in culture media of MnCl2 at 100,300,500,700,900 μmol/L for 24,48 and 72 hours respectively,cell viability was examined by MTT.Cell cycle,apoptosis and mitochondrial transmembrane potential were monitored by flow cytometry (FCM).Results Compared with the control group,24 hours after the incubation,the cell inhibition rates only in 700 and 900 μmol/L MnCl2 groups were significantly increased (P0.05),while at 48 and 72 hours,cells inhibition rates at every MnCl2 group were significantly increased (P0.05).At 48 hours,the results of 500,700 and 900 μmol/L MnCl2 group showed that,compared with the control group,G1 phase was increased,S phase was decreased,the percentage of G2/M and apoptosis were increased (P0.05) respectively.The cell membrane potential was decreased compared with control group.Conclusion MnCl2 could bring down mitochondrial transmembrane potential of PC12 cells and inhibit multiplication of cells and induce cell apoptosis.

Objective To explore the effect of acrylonitrile on nitric oxide(NO)and its possible mechanism.Methods40 mice were randomly divided into four groups.Three exposed groups orally administrated with acrylonitrile doses of 4.65,9.30 and 18.6 mg/kg respectively.The control group was given normal saline.Mice were administrated once a day successively for 6 days and rested for a day.After 21 days exposure,blood samples were collected through removal of eyeballs and the animals were sacrificed.Organ weight ratios of liver,spleen and kidney were measured.Nitric oxide and protein levels in serum samples were determined by assay kits.ResultsResults showed that acrylonitrile could lead to decrease in organ weight ratios of liver,spleen and kidney with an obvious dose-effect relationship.Furthermore,a reverse dose-effect between acrylonitrile exposure and protein level in serum was observed.Nitric oxide levels in serum significantly elevated in three exposure groups.ConclusionsResults suggests that acrylonitrile could exert its toxicity on blood system through interrupting protein metabolism and enhancing NO synthesis.

Objective To evaluate the prevalence of children's dental caries in some nonferrous metal industrial and agricultural areas in Gansu province and to provide a reference for the province's oral health planning.Methods Two hundreds of 5-year-old children and 200 12-year-old in nonferrous metal industrial area and in the neighboring agricultrial area were randomly sampled to examine and complete a questionnairy survey, respectively. The oral examination was included the condition of dental caries and oral hyginene for children of both ages, and dental fluorosis for 12-year-old children.Results The prevalence and DMF index of the 5-year-old children of both the industrial and agricultural areas showed no difference. ②The prevalence, SiC index and DMF index of 12 year-old children in the industrial area showed markedly higher than that of the agricultural area, and the fluorosis index was on the edge of prevalence. ③The oral plaque index of all the children in the industrial area was lower than that of the agricultural area.Conclusion The factors influencing children's dental caries in this nonferrous metal industrial estate may be related with the social status, economical condition and the environment pollution.

Objective To study the injured effect of manganese chloride on the male rats’ reproductive system.Methods 60 Kunming male rats were divided into three groups respectively(high dose group,low dose group and control group).There were 20 rats in each group.Male rats were given intraperitoneal-injection containing manganese chloride at the fixation time every day,which lasted 6 days.Sixty days later,the rats were killed by cervical dislocation.The whole testicles and epididymis were taken out quickly,and then weighed to observe the changes of organ coefficients.Then the tissues were detected for some indexes related to lipid peroxidation damage and movement parameters of sperm.Results With the dose of the poison increased,the male rats’ weights decreased.The organ coefficients of testicles decreased,and there was a remarkable difference between high dose group and control group(P﹤0.05).And the T-AOC also had a remarkable difference between high dose group and control group(P﹤0.05),and the MDA had a remarkable difference in high,low dose groups and control group(P﹤0.05).VCL and VSL both decreased,and there was a remarkable difference between high dose group and control group(P﹤0.05).Conclusion Manganese chloride may cause lipid peroxidation of male rats’ testicles,and also effect on kinetism of sperm.

Objective To study growth and development status in 7-18 year-old primary school and middle school students in Lanzhou so as to provide some basic information for health policy makers and evaluating tools for intervention measures.Methods By use of cluster sampling,students from 52 schools(1 high school,11 junior middle schools,40 primary schools)in Chengguan District were investigated and measured in height,weight,chest circumference and pulse.In the end,all the results were analyzed.Results It showed that height rapid growth appeared during 12-13 years old for boys and the average yearly growth reached 6.8 cm while for girls it appeared during 11-12 years old and the yearly growth reached 6.6 cm.As to the weight rapid growth,the peak status for both boys and girls appeared at 12 years old with no crossing up on the curves of weight growth.Chest circumference for both boys and girls increased continually till 16 years old.On average,for those aged 13-15,boys had equivalent chest circumference as girls.Conclusion Growth and development in adolescents aged 7-18 in Chengguan District showed no deviation from the general population in China in spite of somewhat unbalanced development.

Objective To study the adverse effect of house indoor air pollution on children respiratory system health in Lanzhou city.Methods A retrospective questionnaire investigation on 1 700 children respiratory health was carried out in three kindergartens,three elementary schools involving lower grade pupils in three districts in Lanzhou city.At the same time,the information about the home environment of the children and family background was collected.Applying logistic regression model, the influencing factors were analyzed.Results The over-standard rates of indoor air quality were from 12.4% to 43.8% in Lanzhou.In the non-heating period,the over-standard rates of formaldehyde,benzene,SO_2,NO_2,CO and PM10 in indoor air were 22.6%,14.5%,13.3%,12.4%,0% and 23.3% respectively.In the heating period,the over-standard rates of the pollutants were 27.3%,16.4%,34.6%,28.5%,32.3% and 43.8% respectively.Indoor air pollution was statistically associated with children respiratory symptoms and diseases,the related risk factors were someone smoking in home,house decorated,opening windows, ventilation,heating in winter,sharing bedroom and maternal education.The outdoor air pollution was one of the influencing factors. Conclusion Children respiratory diseases and symptoms are related to many air pollution factors,such as outdoor and indoor air pollution,personal characteristic and family factors,so to prevent and control indoor air pollution,a comprehensive way should be taken in Lanzhou city.

Objective To study the effects of manganese on monoamine contents of midbrains in male rats.Methods 90 Kunming male rats were divided into three groups respectively(30,15 mg/Kg,and the control group).Male rats were given intraperitoneal-injection containing manganese chloride at the same time every six days.They were sacrificed by vertebra disjoint at every 20 days later.The whole brains were peeled off quickly,and were wrapped with silver paper.Then they were put in the liquid nitrogen.The tissues were made into plasm,and then frozen-centrifugal machine was used to distill the upper liquid.The ultravioletradiation detecting system of HPLC was used to mensurate the monoamine in the samples.While the organ relative of male rats was determined.Results Contents of the three monoamines were all decreased than the salt control group and showed a downward trend.The contents of DA in 40 days and 60 days dropped obviously and had remarkable difference after the statistical examination.Male rats' organ relatives in the two groups exposed to manganese were all changed a lot.The organ relatives of liver and spleen were increased,but the rest were all decreased.Conclusion The perennial contacting of manganese may affect the monoamine content of midbrains in the male rats,while also has certain toxic effect to some organs.

Objective To survey free crystalline silica[SiO_2(F)]content,particle size and water-soluble components concentration in the sand-dust storm dust,in order to prevent large-scale non-occupational silicosis(desert lung) prevalence in northwest desert area of China.Methods Atmospheric dust(falldust) were collected in Hetian,Minqin,Zhongwei and Lanzhou city when sand-dust storm befallen and free crystalline silica,particle size ratio and water-soluble components were analyzed according to GB 5748—1985.Results The rate of SiO_2(F) component was over 50%in the original sand,the rate of SiO2(F) component was from 17.36% to 48.09%in the falldust of sand-dust storm,the falldust belongs to crystal dust.The inhaleble particle(particles with amedian diameter of 0.5-10μm) ratio was from 63.3%to 84.1%.The water-soluble components concentration increased as sand-dust storm moving.C1,SO_4~(2-) and NO_3~- content was from 220μg/g,870μg/g and 230μg/g of Hetian to 980μg/g,5 400μg/g and 1 400μg/g of Lanzhou(P0.01).Conclusion The falldust of sand storm inhalation is a high-risk factor for the local peoples to be attacked by non-occupational pneumoconioses.The further studies should be carried out in epidemiological and toxicological fields.