Objective To explore the method for simultaneous determination of arsenic and mercury in drinking water. Methods Atomic fluorescence spectrometry was applied for simultaneous determination of arsenic and mercury in drinking water. The best working conditions of the determination, such as the height of flame of atomizer, current of hollow cathode lamp, reducer, acidity and required amount of NaBH 4 were defined in this assay. Results The determination range of arsenic, the correlation coefficient and detection limit for arsenic were 0～40 ng/ml,0 999 5 and 0 10 ng/ml respectively, and were 0～80 ng/ml, 0 999 3 and 0 02 ng/ml for mercury respectively. The precisions and recovery rates of the simultaneous determination of arsenic and mercury in drinking water were 0 94%～5 61% and 94%～110%. Conclusion This method with advantages such as simple, rapid, sensitive, high accuracy and less interference, was suitable for simultaneous determination of arsenic and mercury in drinking water.

To establish a spectrophotometric method for detecting selenium in drinking water,some subjects,such as the features of absorption spectrum of the reacting product of selenium and diaminonaphthalene,disturbance of other coexisting ions,detection range,detection limit,precision and accuracy were studied.The results showed that:the maximum absorption wavelength of the reacting product of Se4+and 2,3-diaminonaphthalene was 377 nm,the detection limit,molar absorptivity (ε377) and linear range of this method was 0.018 μg/50 ml,2.7×104 L/(mol·cm)and 0.2～10 μg/50ml respectively.The regressive equation was A＝0.077C＋0.014 with a correlation coefficient r value of 0.9999.The relative standard deviation (RSD) and recovery rate were ＜54.7% and 96.5%～106% respectively.This method was simple,sensitive and accurate,could meet the requirement of the routine monitoring of selenium in drinking water.

The paper studied the textual research and the original meaning of 'the liver is the essence of Piji'.It believed that 'the liver is the essence of Piji' contained the main physiological functions of liver but not specific function,and to be expressed through the main functions of liver.It should be understood as regulating the base of human life activities.It revealed the main physiological functions of liver from another aspect,so as to help sub-health research and clinic.

ObjectiveTo study the characteristics of wedge factor of enhanced dynamic wedge (EDW) on Varian 600C linear accelerator . MethodsEnhanced dynamic wedge factors (EDWFs) of different jaw settings were measured on a Varian 600C linear accelerator with FARMER 2570 dosimeter and 2571 0.6 ml Thimble ion chamber. At the same time,equations were used to compute EDWFs of symmetric and asymmetric fields and off axis points. The same measurements were carried out on 30 degree physical wedge in contrast to EDW. The accelerator's jaw position was described according to IEC radiotherapy equipment coordinate standard. Results The EDWFs of symmetric field decreased smoothly while the field size increased. Under the same field,EDWFs decreased as the wedge angle increased and the increasing extent became apparent when the field became larger. In off axis fields formed by the upper independent jaws,only the EDWFs of 60 degree had the tendency to increase when the field center moved toward the toe of the wedge,the rest gave the opposite results. The EDWFs of fixed points varied only by 0.5 percent when the fixed jaw remained at the same place and the moving jaw and lower jaws stayed at different positions. But the WF of 30 degree physical wedge increased by 2.9 percent when the lower jaw settings increased from 4 cm to 40 cm. The EDWFs derived from analytic equations for symmetric and asymmetric fields coincided well with measured results. But at off-axis points,the differences between calculated values and measured data were apparent. ConclusionsThe curve of EDWF versus field size is very smooth. The EDWF of fixed point only depends on the position of the stationary upper jaw,and is affected little by the moving upper jaw and lower jaws. The EDWFs of off axis fields are much more complex than those of physical wedge; it shouldn't be confused in clinical application. The conversion method of rectangular field to square field is of no use when EDW field is confronted. Analytic methods are highly conformal with the calculation of EDWFs of symmetric and asymmetric fields.

Progressive brain injury after traumatic brain injury,including intracranial hemorrhage,cerebral ischemia and edema,is an important factor affecting the prognosis of patients with traumatic brain injury.On basis of reviewing literatures,the research progress on incidence,mechanism,methods for early diagnosis,treatment and prognosis of progressive brain injury after traumatic brain injury was reviewed.

Objective To investigate the risk factors of posttraumatic hydrocephalus (PTH) in patients with moderate to severe traumatic brain injury (TBI).Methods Aretrospective study was conducted for 183 patients with moderate to severe TBI (125 males,58 females;6-91 years of age,mean 48.23 years).According the presence of PTH,the patients were allocated into PTH group (n =34) and non-PTH group (n =149).Risk factors of PTh were assessed by univariate and logistic regression analysis,including gender,age,injury types,injury severity,intraventricular hemorrhage,subarachnoid hemorrhage,midline shift,subdural effusion,therapeutic strategies and skull defect.Association between the boundaries of skull defect and PTH was determined.Results Between-group differences were not significant regarding age,gender,injury types and intraventricular hemorrhage (P ＞ 0.05),but differed significantly in injury severity,subarachnoid hemorrhage,midline shift,subdural effusion,craniectomy and skull defect (P ＜ 0.05).Further Logistic regression analysis confirmed subarachnoid hemorrhage (OR =6.169),interhemispheric subdural effusion (OR =31.743),and unilateral (OR =17.602) and bilateral (OR =30.567) skull defects were risk factors of PTH.Of the patients with unilateral skull defect following decompressive craniectomy,the inferior limit ≤ 10 mm from the zygomatic arch also played a role in the development of PTH (OR =5.500,P ＜ 0.05).Conclusions Subarachnoid hemorrhage,interhemispheric subdural effusion and skull defect are risk factors of PTH.Unilateral skull defects with the inferior limit too close to the zygomatic arch can predispose to the development of PTH.

Objective To systematic evaluate the efficacy of paricalcitol on estimated glomerular filtration rate (eGFR) and proteinuria in non-dialysis chronic kidney disease (CKD) patients.Methods According to the collaborative search strategy,PubMed,the clinical control test database of Cochrane Library,Embase,Chinese Wanfang database,CNKI,VIP database (form the date of database establishment to March 2014) were searched.Published and unpublished literature,abstracts in academic meetings (ASN,WCN,CSN) were also searched by hand.The randomized controlled trials (RCTs) about the efficacy paricalcitol on eGFR and proteinuria in non-dialysis CKD patients were selected.Review Manager Software 5.2 was used for statistical analysis.Results Seven RCTs with a total of 834 patients were included (508 in experimental group,326 in placebo group).No statistical difference of the efficacy on eGFR[SMD=-0.10,95％ CI:(-0.28-0.07),P=0.26] between lower dose paricalcitol (＜ 2 μg/d) group and placebo group,while higher dose (2 μg/d) group reduced eGFR significantly [SMD=-0.45,95％ CI:(-0.63--0.27),P ＜ 0.01].Compared with placebo,paricalcitol reduced proteinuria significantly [OR(95％C1):2.09(1.52-2.58),P ＜ 0.01],and there was no difference between different dose groups [OR(95％CI):1.09(0.62-1.91),P=0.77].Lower dose group [OR(95％C1):0.93(0.57-1.52),P=0.76] and higher dose group [OR(95％ CI):2.08(0.70-6.18),P=0.19] did not significantly increase the risk of adverse events.Conclusions Lower dose paricalcitol (＜ 2 μg/d)has no effect on eGFR in non-dialysis CKD patients meanwhile reduces proteinuria.The higher dose (2μg/d) may reduce eGFR without farther reduction in proteinuria.

Thirty-six cases of delayed tramatic intracranial hematomas are reported in this paper. Among them 9, 5, 10 and 12 cases were epidural, subdural, intracerebral and multiple hematomas, respectively. The initial CT scans showed normal or brain contusions accompanied by a Me hemorrhage in 23 patients, and delayed intracranial hematomas developed after the earlier neurosurgical operations for evacuations of another traumatic mass lessions for urgent decompressions in 13 patients. Delayed hematomas occurred mostly in the acute stage of head injuries and most patients were impacted occipitally. Deterioration of consciousness was the most important manifestation for diagnosis. The responsible mechanisms of delayed intracranial hematomas are investigated and the indications of repeat CT scans or surgery for its early diagnosis are Droposed.

This paper reports 17 cases of traumatic bilateral epidural hematomas. The incidence of these cases was 8.7% of all cases of epidural hematoma. The hematomas in 15 cases were across the midline, and in the other 2 cases were at different location on either side. The mechanism and clinical features of bilateral epidural hematomas were discussed. The indications for early diagnosis were stressed.

Objective To investigate the therapeutic effect of NSR siRNA on nerve regeneration following spinal cord hemi-transsection injury in rats. Methods Rats with T8 spinal cord hemi-trans-section were didded into 3 groups, ie, siRNA group, NS group and control group. SiRNA or NS was in-jected into lateral cerebral ventricle just after spinal cord injury. The therapeutic effect of NgR siRNA was evaluated by using BBB locomotor rating scale, retrograde horseradish peroxidase(HRP)tracing and HE staining. Results BBB locomotor rating scale showed that the recovery of the locomotor function of siRNA group seemed to be better than that of the other two groups from the 4th week, but there was no statistical difference. Retrograde HRP tracing showed a large number of positive cells in the anterior horn of spinal cord, with statistical difference compared with NS group and control group(P<0. 05). Eight weeks after spinal injury, HE staining showed disorderly distribution of the fibres in NS group and control group but serial fibres in the injury region in siRNA group. Conclusion NSR siRNA may promote the nerve regeneration following spinal cord injury.