Background Image clarity during near work is influenced by several factors,such as accommodative lag,pupil size and monochromatic aberrations.Since image clarity during extended reading at near distance has been cited as a possible inducement of myopia in childhood and a possible difference between myopic and emmetropic people throughout life,it is important to examine these factors in myopic and emmetropic myopic juvenile during reading at near distance. Objective The aim of this study was to investigate the relationships among wavefront aberrations,accommodative response and pupil size in early onset and progressive myopes eyes under the different reading status and explore the possible mechanism of the development of myopia as well. Methods Fiflyseven subjects aged from 12 to 16 years were enrolled and grouped as emmetropes,the onset of myopes and progressive myopes.Reading material were Chinese novels presented by rapid serial visual presentation at a distance of 25 cm. Accommodative response and pupil size were recorded by a Grand Seiko WV-500 autorefractor.The Image J software was used to calculate the pupil diameter.Wavefront aberrations were then measured with a WASCA wavefront analyzer. Results Aberrations and accommodative response showed large inter-subjeet variability.With accommodative stimulus of 4 diopter,the accommodative lag in the early-onset of myopes group and progressive myopes group were ( 1.72 ±0. 53) D and ( 1.74 ±0. 44) D, showing larger value in comparison with ( 0. 96 ±0. 55) D of emmetropes group( t＝4.25 ,t=4.47 ,P<0. 001). However,there were no significant differences in accommodative lag between the early-onset of myopes group and progressive myopes group( t = 0. 18, P>0. 05). The mean value of pupil diameter, total RMS value, high-order RMS value, spherical aberration and coma were all significantly reduced with the stimulus varied from 0 D to 4 D( P<0. 01). However,none of the pupil sizs,total RMS value,high-order RMS value,spherical aberration and coma had significant difference among different refractive groups( P>0. 05). Conclusion The early-onset of myopes and progressive myopes had larger accommodative lag. The lower sensitivity to defocus at near reading distance,inducing the larger accommodative lag and hyperopic defocus may be linked to the developing myopia.

Objective To investigate the geographical distribution of excessive iodine in drinking water and to demarc aI|e the excessive iodine regions in Hebei Province.Methods In 173 counties of Hebei Province, town was surveyed as an elementary unit.Five villages were sampled according to the direction of east,west, south,north,center in every town.If the water sources were more than 5 in a village,water was sampled according to the direction ofeast,west, south,north, center, respectively;If the water sources were less than 5 in a village, all were sampled:If the village used water of cental supply,only one sample wag collected.Arsenic-cerium catalysis was used to determine the iodine concentration of drinking water.Results Two thousands and forty-nine towns were investigated and 19 352 water samples were determined in Hebei Province.One hundred and seventy- two towns were confirmed to be excessive iodine areas,where the range of water iodine Wag 0.1～2840.4μg/L The water 8amDle with 18 358 had a water iodine median less than 150.0μg/L The areas with water iodine median less than 150.0μg/L,in between 150.0μg/L and less than 300.0μg/L,and equal to or more than 300.0 μg/L accounted for 94.86%,2.92%and 2.22%,respectively.There were 110 towns with water iodine median being between 150.0μg/L and iess than 300.0 μg/L and 62 towns with water iodine median equal to or more than 300 gμ/L.Exeessive iodine towns distributed in 33 counties of 6 cities involving 5 854 960 residents in'Hebei Provmce. MOBt of the water sources with excessive iodine Cangzhou were deep wells and there was a positive correlation between we depth and water iodine concentration (r=0.430,P<0.01), while they were shallow wells in Handan, Xingtai.Hengshui,and no correlation was found between well depth and water iodine concentration(r=-0.060,-0.119.-0.121,P>0.05).Conclusions Six cities have excessive iodine water resotlrees in Hebei Province, mostly in Handan.xingtai,Hengshui and Cangzhou Cities,which all are low-lying land.The water with excessive iodine is hypogene,and the towns with excessive iodine water distributein patchy or spot pattern.

Objective To analyze the therapeutic effect and prognosis according to a new CT classification of traumatic posterior occipital epidural hematomas (POEH). Methods We classified the CT presentation of 104 patients with POEH by sinus transverses: type Ⅰ hematomas were defined as up-sinus transverses; type Ⅱ hematomas were defined as sub-sinus transverses and type Ⅲ hematomas were defined as straddling sinus transverses. The above types were divided into unilateral or bilateral subtypes. Bone flap craniotomy through a median posterior approach was performed in patients with unilateral hematoma adjacent to the midline. Bone flap craniotomy through a median suboccipital approach was adopted for patients with bilateral middle occipital hematoma. Results Type Ⅰ enjoyed mild symptoms, good curative effect and low mortality rate (7%). Type Ⅱ and Ⅲ had serious symptoms and high mortality rate (13.3%, 16.6%, respectively). Conclusion The classification of the CT presentation of POEH is helpful in confirming the diagnosis, drawing up the scheme of treatment and judging the prognosis.

Objective To identify the impact of age and gender on cardiac structure and left ventricular function in normal Chinese by echocardiography. Methods Cardiac structure, valve flow velocity and cardiac function were measured by echocardiography in 15 692 healthy volunteers. Subjects were grouped by age at 5 years interval in population older than 5 years. Children under 5 years were divided into 3 age groups(<1 years,1-3 years,4-5 years). Hierarchical cluster analyses were performed for ages, based on indexes of cardiac structure and function respectively. Results Six groups (< 1 years, 1-3 years,4-5 years, 6-10 years, 11-20 years, ≥21 years) were generated after the age hierarchical cluster analyses based on index of cardiac structure. Four groups (≤30 years, 31-50 years, 51-80 years,≥81 years) were generated based on spectral current flow. Six groups (< 1 years,1-3 years,4-5 years, 6-10 years, 11-15 years, ≥16 years) were generated baaed on left ventricular systolic function and five groups (≤15 years, 16-30 years, 31-50 years, 51-80 years, ≥81 years) were generated based on left ventricular diastolic function. Cardiac structure index were similar between male and female in age groups ≤ 10 years and significantly lower in females than males in age groups ≥ 11 years (P < 0.05). Valve flow velocity was similar between male and female in various age groups (P >0.05). Left ventricular systolic function was similar between male and female in age groups ≤10 years but was significantly higher in males than females in age groups ≥11 years(all P <0.05). Left ventricular diastolic function was similar between female and male in various age groups (P > 0.05) and equally decreased with aging in both female and male subjects. Conclusions The cardiac development in Chinese population can be divided in 6 phases and becomes stable in subjects older than 21 years, left ventricular systolic function becomes stable in subjects older than 16 years and the left ventricular diastolic function declines physiologically with aging.

Background Roux-en-Y gastric bypass (GBP) is the main surgical procedure used in type 2 diabetes.The objective of this study was to evaluate the different types of GBP in treatment of type 2 diabetes.Methods Patients with type 2 diabetes were randomly divided into two groups:those who underwent gastrojejunal loop anastomosis bypass and those who underwent gastrojejunal Roux-en-Y bypass.Blood glucose alterations,operation time,and operation complicatiors were observed.Results Gastrojejunal loop anastomosis bypass and gastrojejunal Roux-en-Y bypass were both effective in the treatment of selected patients with type 2 diabetes.Compared with gastrojejunal Roux-en-Y bypass,gastrojejunal loop anastomosis bypass had the advantages of easier implementation,shorter operation time,and fewer operation complications.Conclusions Gastrojejunal loop anastomosis is effective in treatment of type 2 diabetes.It is safe,easy to implement,and worthy of clinical popularization.

Objective To observe the effect and safety of supplying sodium chloride in the treatment of patients with severe heart failure.Methods Consecutive 51 hospitalized patients with severe heart failure and cardiac edema were included in this study.Normal diet (6 g NaCl/d) was supplied to all patients.On the basis of controlling fluid intake and treating related etiological factors as well as standard medications including furosemide for severe heart failure,patients with mild hyponatremia (serum sodium level 130- 134 mmol/L) ate additional salted vegetables,patients with moderate hyponatremia (serum sodium level 125 - 129 mmol/L) and severe hyponatremia (serum sodium level ＜ 125 mmol/L) ate additioual salted vegetables and were received additionally intravenous 3％ NaCl hypertonic saline infusion ( 10 ml/h) until reaching normal serum sodium level.Results On admission,37.25％ ( 19/51 ) patients had hyponatremia.During the first two weeks hospitalization period,88.24％ (45/51) patients were treated with intravenous diuretics and total incidence of hyponatremia was 64.71％ (33/51),mild hyponatremia was 50.98％ (26/51),middle and severe hypouatremia was 13.73％ (7/51) ; among them,hyponatremia lasted less than 3 d in 57.58％ (19/33) patients and ≥3 d in 42.42％ ( 14/33 ) patients.Heart failure exacerbation and hypernatremia were not observed in patients receiving additional sodium chloride therapy.Hospitalization time was similar among patients with different blood natrium levels [ average ( 16 ± 12) d ].Fifty out of 51 (98％) patients discharged from the hospital with improved heart failure symptoms and signs.Conclusion Supplying additional sodium chloride could rapid correct hyponatremia in heart failure patients with or without intravenous diuretics therapy which might contribute to a favorable prognosis in hospitalized heart failure patients.