The conditions of color-reaction of boric acid with 1-(2-hydroxy-3-methoxybenzylidence-amino)-8-hydroxynaphalene-3-6-disulfonic acid in buffer medium of ethamine at pH 6.5 were studied in the assy.The maximum absorption wavelength of this coordination compound was 420 nm.The coordination reaction showed a good linear relationship at the concentrations of boric acid of 0.4～0.6 mg/L.The detection limit and molar absorptivity (ε) was 0.08 mg/L and 4.6×104 L/(mol·cm) respectively.This method presented perfect selectivity under the existence of EDTA solution,had been successfully applied in the determination of boric acid in natural mineral water for drinking.

Experimental methodssintraperitoneal injection of diazepam,r-aminobutyric acid (GABA) receptor antagonist (picrotoxin) and GABA synthesis inhibitor (iso-niazid) ;the pain threshold and serotonin ( 5 -HT) content in the brain are measured with spectrofluorometry.The effect of diazepam on ACTH analgesia (AA) is abstracted and the possible mechanisms of diazepam effect are studied.Results: diazepam increases the effect of AA.picroloxin and isoniazid reduce it and antagonize the analgesia effect of ACTH; diazepam increases the content of 5-HT in hipocampus,hypothalamus and midbrain;diazepam + ACTH increases,more than AC-TH or diazepam singly,the level of 5-HT in the 3 brain regions; picrotoxin and isoniazid reverse the effect of diazepam and ACTH on the content of 5-HT in the 3 brainsites; potentiation of diazepam on AA is antagonized by naloxone and atropine.

Objective To study a rapid method for determination of trace formaldehyde in drinking water by oscilloscopic polarography.Methods In the base solution of0.01mol/L H 3 PO 4 ,the reaction product of formaldehyde and phenylhydrazine hydrochloride on the drop mercury electrode revealed a sensitive second order derivative polarographic wave at a pick electric potential-0.76V(VS?SCE).The optimum conditions and interference by other coexisting ions were analyzed.Results The de-tection limit,linear range,recovery rate,relative standard deviation(RSD)of the method were0.002mg /L,0.005-0.25mg /L,94.0%-103.0%,and0.05).Conclusion The method was simple,rapid,sensitive and highly specific.The analytical speed was about 50-60samples /h,which was suitable for the determination of trace formaldehyde in drinking water.

This paper is to introduce our newly designed driving system used to push a microelectrode forward into the recording position in animal experiments. The instrument consists of two parts: 1. the hydraulic fine manipulator and 2. the holding mechanism and the secrew driving device of the microelectrode.Carefully pass a long glass shaft microelectrode through a stainless steel guide tube. Both the microelectrode and the guide tube are fixed on the frame of the instrument with two holding mechanisms. The frame is then connected to the chassis of the instrument which has previously been embedded in the skull of the experimental animal. Turn the screw driving device and both the microelectrode and the guide tube are moved forward. Stop turning when the guide tube penetrates the dura. Then the hydraulic fine manipulator is used to push the microelectrode into the recording position.A long glassshaft microelectode produces little injury to the brain tissue, thus it facilitates the repeated experiments on animals. The chassis of the driving system is implanted into the skull of the experimental animal with stereoscopic technique and its relative position with the brain tissue can not be changed during experiment. Slight movement of the animal head will in no way interfere with the recording.

Objective To investigate the diagnostic value comparatively of CT and radiography in pneumoconiosis.Methods Chest radiographic and CT images were analyzed retrospectively in 52 cases with pneumoconiosis.Results The pulmonary disseminated small shadowes (diameter 10 mm),13 cases and 9 cases were detected by CT and radiography respectively.20 cases (5 pneumonia,3 pulmonary tuberculosis,1 lung cancer,6 pneumothorax,4 pulmonary emphysema) and 10 cases (1 pneumonia,1 pulmonary tuberculosis,6 pneumothorax,2 pulmonary emphysema) with complications were showed by CT and radiography respectively.Conclusion CT is not superior to radiography in diagnosis of simple pneumoconiosis,but CT is superior to radiography detecting the big shadow of lung and complications,and it can help radiologists to avoid mistakes.

Objective To explore the high-resolution CT manifestation of chronic otitis media with cholesteatoma. Methods clinical and high-resolution CT manifestation of 31 cases of chronic otitis media with cholesteatoma were analyzed. All the cases were confirmed by operation and pathology. Results High-resolution CT can accurately show the signs of soft-tissue occupancy and bony-erosion of cholestcatoma in middle ear which originate from various sites and of various sizes.confirmed by operation, accuracy were as high as 93.5%-100% . Conclusion high-resolution CT is extremely accurate in diagnosis of chronic otitis media with cholesteatoma.

Objective To study MR imaging features of transient bone marrow edema syndrome of the hip so as to improve its diagnosis and differential diagnosis.Methods MR images of transient bone marrow edema syndrome of the hip in 13 patients were retrospectively analyzed in combination with literature review.Results The bilateral hips were affected in 4 patients.The single hip was affected in 9 patients,left hip in 6 and right hip in 3.The MR images demonstrated low signal intensity in all 13 patients on T1WI,and normal signal intensity in 2 patients,moderate or high signal intensity in 11 patients on T2WI,and high signal on T2 fat suppressed or STIR images in all 13 patients.The bone marrow edema pattern involved the femoral head and neck in 13 hips,the femoral head and neck and the intertrochanteric region in 4 hips.A small joint effusion was observed in 8 hips on T2WI.The configuration of femoral heads were normal.Conclusion Correct judgement of MRI manifestations of transient bone marrow edema syndrome of the hip can improve its diagnosis and differential diagnosis.

Objective To study the cell immunity and eytokines responses to avian influenza A H5N1 virus infections in a BALB/c model to better understand the pathogenesis of H5N1 avian influenza disease. Methods Two hundred and twenty BALB/c mice of the infected group were inoculated with 0.1 ml (10-4.875 TCID50) of A/Goose/Guangdong/NH/2003 ( H5N1 ) virus intra-nasally. Fifty control mice received noninfectious allantoic fluid and another fifty control mice received normal sodium. Blood and spleen samples were collected from the live mice every 24 h during the 14 d post-infection. The changes of CD3 + T cells , CD4 + T cells, CD8 + T cells for cell immunity in blood circulation and spleen were detected by flow cytometry. And the cytokines and antibody responses in blood circulation were detected by ELISA. Necropsy was performed on mice that died during the experiment and those euthanized at end of study. Results Avian influenza A( H5N1) virus infections can make damages to the cell immune system transiently. The CD3 + T cells, CD4 + T cells, CDS + T cells declined at 24 days post infection in blood circulation and declined at 5-8 days in spleen, then recovered to the normal level gradually. The eytokines responses to the infections can be detected: the level of IFN-γ,TNF-α declined, IL-4, IL-18, IL-10 increased, and IL-2 changed little. The antibody increased rapidly from day 7 post infection until the end of the study (day 14 post infection). Conclusion Collectively, avian influenza A(H5N1) virus can cause cell immunity deficiency and an imbalance in the level of eytokines, which may contribute to the unusual severity of disease caused by the H5N1 avian influenza virus.

Objective To test our hypothesis that sensitivity to avian influenza A(H5N1)virus varies among mouse strain backgrounds, we compared the pathogenicity of H5N1 viral infection in 5 mouse strains. Methods Onehundred-fifty mice from 2 inbred strains(BALB/c and C57BL/6), and 3 outbred stocks(ICR, NIH Swiss, and KM Swiss)were used. Thirty mice of each strain were subjected to an infected group(20 mice), in which mice were inoculated with 0. 1 mL(104.875 TCID50)of A/Goose/Guangdong/NH/2003(H5N1)virus intra-nasally; ten control mice received noninfectious allantoic fluid. Clinical signs were assessed daily for 14 days post-infection. Necropsy was performed on mice that died during the experiment and those euthanized at end of study. Tissue samples were collected for viral isolation and pathological analysis. Results H5N1 virus infection can cause respiratory illness in all 5 strains with severe or minor acute respiratory distress symptoms, but with different mortality rates: 70% in BALB/c; 50% in ICR; 40% in NIH Swiss; 25% in C57BL/6; and 10% in KM Swiss mice. Necrotizing interstitial pneumonia was found in all cases of death. The virus was isolated from the lungs of all infected dead mice. Conclusion A/Goose/Guangdong/NH/2003 (H5N1)virus can infect all mouse strains used in this study, and can cause clinical symptoms and pathological changes similar to those found in humans infected with HSN1 viruses. However, the pathogenicity of H5N1 viral infection varies significantly between the different mouse strains. Thus, in future study of H5N1 virus infections the mouse strain most relevant to their particular research purpose should be selected as animal model.

The effects of intramuscular or intracerebroventricular injection of penta-gastrin(PG) on the action potential amplitude (APA) of the myocardial cells and the heart rate(HR) were studied. The results were as follows:1 ) Injection of 10?g/10?l of PG into one of the lateral ventricles of the ratfailed to produce any effect on APA or HR. When the dosage of PG was doubled(20?g/10?l), then HR could be slowed down significantly (P