Objective To develop the methods for determination of nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace. Methods Nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace were collected by active carbon tube,desorbed in ethyl acetate solution and detected by capillary gas chromatography (GC-FID). Results The linear concentration range of nitromethane,nitroethane,1-nitropropane,2-nitropropane was 43.2-345.3,177.6-1 421.0,68.5-547.7,24.1-192.4 ?g/ml respectively and the relative standard deviation was 1%-5%. Sampling efficiency was 100%,desorption efficiency was 91%-93%. The sample could be resaved at 4-10 ℃ for 5-7 days. Conclusion The method is applicable to determination of nitromethane,nitroethane,1-nitropropane,2-nitropropane in the air of workplace.

Objective To study cortactin function in cancer cell endocytosis.Methods We applied cortactin siRNA interference to MDA-Mb-231,a human breast adenocarcinoma cell line in which cortactin was over-expressed,and introduced anti-cortactin immunoreagents into the cells with BioPorter system to interfere with cortactin function in vivo.Capture-ELISA assay was used to measure transferrin uptake.We used immunoblot assay to assess the effect of cortactin knock-down and immunoflurescence microscopy to examine the effect of cortactin down-regulation on transferrin uptake.Results Interference of cortactin function in cells resulted in impairment of transferrin endocytosis.Transferrin fluorescent intensity in cytoplasm in cortactin siRNA treated-cells was significantly reduced in comparison to that of mock-treated cells.Less than 50% of cells subjected to cortactin siRNA treatment had normal transferrin uptake.Endocytosis in MDA-Mb-231 cells introduced with cortactin antibodies was impaired as well,showing a 30%～ 60% reduction in transferrin uptake.Conclusion Crtactin,an actin-binding protein,plays an essential role in cell endocytosis.

Objective To study spiral CT features and pathological basis of nodular goiter ,so that to improve the diagnostic accuracy of nodular goiter.Methods CT findings in 34 patients with nodular goiter confirmed by pathology were retrospectively analyzed and compared with pathological findings. Results Thyroid density in the patients with NG was lower than that in the normal. There was no statistically significant difference in the density between single and multi-NG. Most lesions(28/34) were multiple, round or oval, with different size and smooth edges. The density of majority lesions was lower than nearby normal tissue. Most lesions (27/34) were uniform in density. Central necrosis(5/34)often appeared in the bigger lesions(diameter＞3.0 cm). The CT value of the lesions was increased (47.1±42.2) HU after enhancement,but lower than surrounding thyroid tissue. Calcifications in the lesions(6/34)were puncticular,plaque or crustiform. Single or multiple cystic-solid or solid nodules could be seen in pathology, without a continuous capsule in the majority. Some patients (5/13) with single NG shown on imaging study were multi-NG in the pathology. Three cases of diffuse NG showed by CT were malignant in pathology. Conclusion There are certain characteristics for NG on spiral CT. Comprehensive evaluation may improve the accuracy of CT diagnosis.

Objective To screen college students contacts of tuberculosis index cases among colleges located in Haidian District,Beijing,so as to provide evidence for the modification of screening strategies for college students.Method The purified protein derivative test (PPD) and chest X-ray examination were carried out in colleges,located in Haidian District from March 2015 to March 2016.The basic demographic characteristics,tuberculosis infection and detection of patients,etc were analyzed.Results A total of 88 cases of tuberculosis index cases were diagnosed,and 3 604 college students contacts were detected 16 pulmonary tuberculosis cases were detected among close contacts,and all patients were negative,the detection rate was 443.95/100 000.Among the 3 604 close contacts,the positive rate of PPD was 8.32％.With the increase of the diameter of the PPD reaction,the detection rate of tuberculosis patients increased significantly (xtrend =8.06,P ＜0.001).During the period of outbreak,the PPD positive rate and the detection rate of patients were significantly higher than that of non-outbreak period,and the difference was statistically significant(all P ＜0.05).Conclusions It is necessary to strengthen the screening of tuberculosis among college students,and to find out the infected persons and patients as early as possible,so as to prevent the outbreak of tuberculosis.

Adolescent ; Adult ; Female ; Fibula ; injuries ; Fractures, Bone ; therapy ; Humans ; Male ; Manipulation, Orthopedic ; methods ; Middle Aged ; Retrospective Studies ; Splints ; Tibial Fractures ; therapy ; Traction ; methods ; Treatment Failure

Objective To study the method of using phantom test for daily quality assurance of on board image(OBI) system. Methods The routine procedures of radiotherapy, including CT simulation, planning,setup,cone beam CT(CBCT) scan and kilovolt X-ray orthogonal film were carried out on a head phantom. The procedures repeated once a day in the following 10 days. The geometric errors of the phantom were recorded. Results The geometric errors of the phantom by CBCT were [0.06±0.11] cm, [0.03±0.05] cm, [0.07±0.07] cm and [0.03±0.10] cm in longitudinal, vertical, lateral and rotation directions, respectively. The geometric errors of the phantom by kilovolt X-ray orthogonal film were [ 0.04±0.10] cm, [0.03±0.05] cm, [0.08±0.06] cm and [0.05±0.05] cm, respectively. The differences of geometric errors of the phantom by CBCT and kilovolt X-ray orthogonal film were not significant(t = 0.44,P=0.667 in longitudinal direction ; t=0.00, P=1.060 in vertical direction ; t=0.34, P=0.735 in lateral direction; t=0.58,P=0.568 in rotation direction). Conclusions The OBI system of our accelerator is reliable and at excellent performance status. The method by using phantom test for the daily quality assurance of OBI system is easy and reliable.

To synthesize salbutamol immunogen and develop an enzyme immunoassay (ELISA), a new salbutamol immunogen was synthesized using 4-aminobenzoic acid as a linker to connect hapten with carrier protein. An enzyme immunoassay based on the antibody prepared was developed and applied to detect salbutamol residue spiked in swine liver. An unusual coating antigen, clenbuterol-ovalbumin (OVA) conjugate instead of salbutamol-OVA conjugate, was used in the immunoassay and the results were discussed based on the structures of related compounds. The antibodies showed high sensitivity in the heterologous assay when using clenbuterol-OVA as a coating antigen, with an IC50 value of 8.97 ng mL(-1) toward salbutamol. The antibodies prepared showed high cross-reactivity with clenbuterol (107%) and were promising for the simultaneous determination of salbutamol and clenbuterol residues in food and food products. Recovery rates from the salbutamol-spiked swine liver samples were in the range of 70%-99%, while the intra-assay and inter-assay coefficients of variation were <13.3% and <14.3%, respectively. In summary, the antibodies of salbutamol have been successfully prepared. Sensitive and stable analysis for the detection of salbutamol residues in swine liver was obtained based on the competitive ELISA methods developed in this study.

Objective To characterize CD4+CD8+double-positive T ( DPT) cells in PBMCs from patients with tuberculosis(TB).Methods PBMCs were isolated from peripheral blood samples collected from patients with TB and healthy subjects.The subsets and percentages of CD4+T, CD8+T and DPT cells in PBMCs were determined by flow cytometry.Cell surface markers ( CD45RO, CCR7 and CD25 ) and intracellular cytokines ( IFN-γand TNF-α) were detected directly and after ESAT-6/PPD stimulation.Re-sults Patients with TB showed a significantly increased DPT cells as compared with the cured individuals and healthy subjects (P<0.005).The levels of DPT cells were gradually decreased down to normal upon the treatment of pharmacotherapy.DPT cells expressed higher levet of CD25 than CD4+T and CD8+T cells ( P<0.005 ) . DPT cells could express more IFN-γand TNF-αupon the stimulation of ESAT-6/PPD (P<0.005).The analysis of memory phenotype indicated that DPT cells were memory T cells.Conclusion DPT cells in peripheral blood of the patients with tuberculosis played a critical role in protective immunity against tuberculosis.The alterations of DPT cells in PBMCs during the period of pharmacotherapy might be a potential indicator for the prognosis of pulmonary tuberculosis.

A novel and sensitive HPLC-UV method has been developed for the simultaneous determination of twelve major compounds in Longdan Xiegan Pill.The chemical profile of the twelve compounds,including geniposidic acid (1),geniposide(2),gentiopicroside(3),liquiritin(4),crocin(5),baicalin(6),wogonoside(7),baicalein(8),glycyrrhizic acid (9),wogonin (10),oroxylin A ( 11 ) and aristolochic acid A (12),was acquired using high-performance liquid chromatography-diode array detector coupled with an electrospray tandem mass spectrometer (HPLC-DAD-ESI-MS).The analysis was performed on a Dikma Platisil ODS C18 column (250 mm × 4.6 mm,5 μm ) with a gradient solvent system of acetonitrile-0.1％ aqueous formic acid.The validation was carried out and the linearities ( r ＞ 0.9996),repeatability (RSD＜1.8％),intra- and inter-day precision (RSD＜1.3％),and recoveries (ranging from 96.6％ to 103.4％ ) were acceptable.The limits of detection (LOD) of these compounds ranged from 0.29 to 4.17 ng.Aristolochic acid A,which is the toxic ingredient,was not detected in all the batches of Longdan Xiegan Pill.Furthermore,hierarchical cluster analysis was used to evaluate the variation of the herbal prescription.The proposed method is simple,effective and suitable for the quality control of this traditional Chinese medicine (TCM).

OBJECTIVE: To evaluate the clinical outcomes of single-balloon kyphoplasty in the treatment of thoracic osteoporotic compression fractures via extrapedicular approach METHODS: From July 2004 to May 2008, 38 cases (52 vertebra) of thoracic osteoporotic fractures were treated by balloon kyphoplasty via unilateral extrapedicular approach, including 12 males and 26 females with an average age of 60.3 years (range 55-72 years). There were 34 cases of primary osteoporosis, and 4 had administrated hormone due to other diseases for over 6 months. Symptomatic levels ranged from T_4 to T_(12) confirmed by physical examination, MRI and X-ray. The pain relief, restoration of vertebral height and kyphosis correction were compared before and after operation by using visual analogue scale (VAS) and radiograph, respectively. In addition, bone cement leakage location and complications were recorded. RESULTS: Operation were successfully performed in 38 cases with an average injection of bone cement volume of (3.2+ 1.4) mL (2.25-4.60 mL in unilateral infusion). The mean time of surgery was 25-55 minutes, and that of follow-up was 9.5 months (6-24 months). Back pain of 36 cases was improved, and the VAS 3 days postoperatively and the final follow-up was significantly reduced (P < 0.05). The vertebral anterior margin and median height following surgery were significantly improved detected by X-ray (P < 0.05), and average median height restoration was (50.90+34.60)%, but no significant change was found in posterior height (P > 0.05). No lateral wedging or changes in the coronal alignment was found. Three cases (5 vertebra) had cement leakage: the bone cement of 1 case leaked to posterior margin through the puncture channel, and 2 cases leaked to lateral vertebra through vertebral venous system without any adverse event. The patients could move the second day after surgery, discharged from the hospital at days 3-4, and restored to normal life at 1 month postoperatively. No blood vessel or spinal cord puncture injury or pulmonary embolism, or blood vessel embolism was found. CONCLUSION: Unilateral extrapedicular kyphoplasty is safe and effective in treating thoracic osteoporotic fractures. It rapidly releases backache, restores the body height of fractured thoracic vertebrae and improves quality of life of the patients.