Objective To investigate MRI features of cystic oligodendrocytoma.Methods MRI features of 10 patients with oligodendroglial tumors proved with operation and pathology were analyzed retrospectively.Results Among 10 patients,lesionslocated on the supratentorium in 8 patients,while on the cerebellar vermis in 2 patients.Solitary lesion was found in 9 cases,and multiple lesions were found in 1 case.Complete cystic lesions were observed in 4 cases,large cystic lesions with solid nodules were found in 3 cases,and multi-cystic lesions were found in 3 cases.Smooth cyst wall of lesions were found in 7 cases,locally depressed and rough wall were found in 3 cases.Calcifications were found in 3 cases.Mild peritumoral edema was found in 9 cases,moderate to severe edema was found in 1 case.The lesions significantly enhanced in 3 cases,ring enhanced in 3 cases,and locally enhanced in 1 case.Conclusion COD is difficult to diagnose,but has certain MRI characteristics.COD should be considered when supratentorial complete cystic lesion or large cystic lesion with septum and/or solid nodule was found with MRI.

Objectives To investigate the occipital cortex metabolite alterations in repetitive and severe neonatal hypoglycemia rats treated with sodium pyruvate and to reveal the protective role of sodium pyruvate using high resolution 1H nuclear magnetic resonance spectroscopy.Methods Thirty-six 2-dayold Sprague-Dawley rats were randomly divided into hypoglycemia group and pyruvate group with 18 rats in each group.Rats in both groups received intraperitoneal injections of insulin (40 U/kg body weight) at 2,4 and 6 days of age to induce severe hypoglycemia (blood glucose value ≤ 1.4 mmol/L).In the hypoglycemia group,2.5 hours after insulin injection,intraperitoneal injection of 50％ glucose (2 ml/kg) was administered to terminate hypoglycemia,while in the pyruvate group,50％ glucose (2 ml/kg) and sodium pyruvate solution 2.5 ml/kg (500 mg/kg) were injected.Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay was used to observe the status of injured neurons in six neonatal rats,and metabolite changes in occipital cortex of the other 12 rats were detected by 1H nuclear magnetic resonance spectroscopy.The difference between the two groups was compared by independent-samples t test.Results Neonatal rats of both groups reached severe hypoglycemia level 2.5 hours after insulin injection.Compared with hypoglycemia group,pyruvate group had fewer injured neurons (45±5 vs 113 ± 12,t=0.782,P=0.013) and lower injured index in the occipital cortex (0.15 ± 0.03 vs 0.36 ± 0.06,t=l.143,P=0.020).Pyruvate group showed significant decreases in the concentration of taurine [(13.31 ± 2.06) vs (18.44 ± 3.86) mol/kg,t=8.231],glutamine[(1.50 ± 0.24) vs (2.02 ± 0.40) mol/kg,t=3.137],glutamate[(7.04 ± 0.95) vs (9.40 ± 1.73) mol/kg,t=6.449],aspartate[(1.51 ± 0.28) vs (2.15 ± 0.58) mol/kg,t=2.561] and creatine [(6.37±0.99) vs (8.46± 1.77) mol/kg,t =4.226] in the occipital cortex (all P'＜0.017).Conclusions Simultaneous use of glucose and sodium pyruvate to terminate hypoglycemia in repetitive and severe neonatal hypoglycemia rats can effectively alleviate severe hypoglycemia-induced occipital lobe damage via regulating excitatory amino acid neurotransmitters,energy metabolism and other metabolic pathways.

Objective To develop a Jingcen DY?1 type spraying tanker for Oncomelania hupensis snail control and evaluate its effect of field application as well as the cost. Methods The currently available tractor was used as a vector,and the mechan?ical and electrical equipments and containers were integrated with shafts,pipelines and electric lines to produce a spraying tank?er for snail control,with the functions of carrying people and molluscicides,generating electric power and getting water,mixing stocking solutions,adjusting molluscicide solutions evenly,and spraying drugs. The volume of the molluscicide solution,flow rate of water injection,and the flow rate,range and advance speed of the spray gun were tested,and the solution concentrations of molluscicide in the tanker and at the muzzle of the spray gun at different time were detected. Meanwhile,the molluscicidal ef?fect and cost of the spraying tanker were analyzed by the field test. Results The volume of the liquid storage pot of the Jingcen DY?1 type spraying tanker was 1 800 L,the flow rate of water injection was 400 L/min,the flow rate and the spray range of the standard spray gun were 110-200 L/min and 19.70-23.50 m,respectively,the efficiency of drug spraying of the spraying tanker was 6 000 m2/h,and the ratio of spray width(m)to march speed(m/min)was 1∶200. When 5 min post mother liquid recirculat?ing ,the average concentration of the molluscicide at the upper? ,middle? and lower?layers of the liquid storage pot was (1 030.39 ± 43.00)mg/L,with a variation coefficient of 4.17%. The average concentration of the molluscicide in the spraying process(spraying for 2,4,6,8,9 min)was(953.00 ± 68.87)mg/L,with a variation coefficient of 7.22%. The concentration of the residual drug in the liquid storage pot post spraying was 1 000.43 mg/L,which reached the effect concentration for snail con?trol. After spraying for 7 days in the field,the average density of living snails reduced by 88.20% as compared to that before spraying,and the adjusted mortality of snails was 87.65%. The unit cost of Jingcen DY?1 spraying tanker was 0.086 7 Yuan/m2, which reduced by 58.20% as compared to that of the conventional spraying tanker. Conclusions Jingcen DY?1 type spraying tanker for snail control which integrates various equipments together can effectively control the concentration and dose of the mol?luscicide,and the machine is labor?saving,efficient,economic and well adapted,and is worthy to be widely applied.

Objective To invesigate the value of contrast-enhanced spiral CT scan in diagnosing renal pelvic carcinoma.Methods All 35 cases with renal pelvic carcinoma confirmed by surgical pathology underwent plain and contrast-enhanced (including 4 phases) spiral CT scans before operation.CT data were reviewed retrospectively in comparison with surgical and patholgical results.Results CT findings of renal carcinoma could be classified into 3 types:type Ⅰ,the lesions limited within the renal pelvis in 25 cases;thype Ⅱ,the lesions were out of the renal pelvis and had indefinable margins with the renal parenchyma in 6 cases;type Ⅲ ,only showed the pelvic wall thickened with hydronephrosis in 4 cases.On contrast-enhanced CT scan,inhomogeneous enhancement of the lesions was presented in cortical phase,the intensity of enhancement was not obviously changed in 13 cases in parenchymal and excretion phases,but the lesions were still hypointense in comparison with renal parenchyma,14 cases demonstrated inhomogeneous enhancement of the lesions in delayed phase.Conclusion Contrast-enhanced spiral CT scanning is valuable in diagnosing renal pelvic carcinoma and renal delayed phase should be emphasized.