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Fourier transform spectrometer is an important instrument in the remote sensing applications. There are phase error problems in the Fourier transform spectrometer signal processing procedure. In the present paper, the cause of phase error of Fourier transform spectrometers is shown firstly. It is mainly because of inaccuracy of sampling. Then the nonlinearity of phase error is analyzed. It is suggested that it is because that the interferogram is of finite length and the interferogram is discrete that this nonlinearity exists. The authors studied this problem with a new method. The nonlinearity is shown by rigorous derivation and the authors draw the conclusion by reasoning. Then through the nonlinearity of phase error, the authors have a discussion on the possible error in the Mertz phase correcting method. The possible error lies in the phase interpolation procedure, a part of Mertz method. A method consisting of zero adding and transforming is given to reduce this error. The methods are compared and illustrated by an experiment which uses simulated interferogram from standard spectrum library. The experiment demonstrates that the method of zero adding and transforming can reduce the phase error of phase interpolation and improve the problem of rapid phase change under some circumstances, which can help get better spectrum.

Objective: To study the etiology of influenza-like illness (ILI) in Beijing, and to investigate the impact of antibiotic treatment on outcomes., Methods: This was a prospective cohort study. Patients with diagnosis of influenza-like illness were prospectively enrolled for study of bacterial and viral pathogens. Demographic characteristics, underlying diseases, respiratory and extrapulmonary symptoms, laboratory tests were also collected for analysis of relationship between drug therapy and outcomes., Results: A total of 476 cases were enrolled between Dec. 2006 and Apr. 2007, of whom 454 cases were used for analysis. Influenza virus was the most common pathogen( n = 197, 43.4%), with other pathogens rarely seen. The mean age of the patients was (33 +/- 13) years, and the ratio of male to female was 1.1:1. Twenty four patients (5.3% ) received influenza vaccine. The rate of antibiotic prescription after onset of illness was 63.4%, but none received antiviral drugs such as Oseltamivir and amantadine. Compared with influenza-negative patients, patients with influenza were older, had more underlying diseases and had greater severity of symptoms such as cough, sore throat, headache and myalgia (but with no statistical differences). The influenza syndrome (T > or = 39 degrees C plus cough, sore throat and headache or myalgia) was more common in the influenza group compared to the influenza-negative patients (P < 0.05). The ratio of antibiotic prescription was 67% in the influenza group, and the total white blood cell and platelet count, percentage of neutrophils were higher in antibiotic treatment patients compared with non-antibiotic treatment patients (P < 0.01). The cost in patients who received antibiotics was twice as much as non-antibiotic treatment patients (P < 0.05), but the defervescence time and respiratory symptom alleviation time did not differ. Cox regression analysis showed that the total white blood count and the differentials (OR value 1.049 and 1.014, respectively), but not antibiotic use were the independent risk factors for longer defervescence time., Conclusion: Influenza virus was the most common pathogen for adult patients with ILI in Beijing city during the winter and the spring seasons. Antibiotic treatment of adult patients with ILI did not improve illness resolution, while the cost was increased significantly.

Background & Objective: In vitro studies proved that sodium butyrate (NaB) could stimulate cell differentiation, inhibit cell proliferation, and induce cell apoptosis in various tumors. This study was to evaluate the preventive effects of coloclysis of NaB on 1,2-dimethylhydrazine (DMH)-induced tumorigenesis of colorectal cancer in mice., Methods: The mice of Kunming species were divided into 5 groups and received relevant treatments: DMH alone group (with subcutaneous injection of 30 mg/kg of DMH weekly for 11 weeks), control (normal saline, NS) group, DMH plus low dose of NaB (1.25 mol/kg, 24-week coloclysis) group, DMH plus high dose of NaB (2.5 mol/kg, 24-week coloclysis) group, and high dose of NaB group. The mice were killed in batches at the 12th, 18th, and 24th weeks of carcinoma induction separately. The incidence of colorectal tumor in each group was observed. Meanwhile, the general condition, body weight increasing, liver and renal functions, and pathologic changes of liver, kidney, lungs, and pancreas of the mice in DMH plus high dose of NaB group were also observed., Results: No tumor was observed at the 12th week in each group. At the 18th week, the tumor incidence was significantly higher in DMH alone group and DMH plus low dose of NaB group than in DMH plus high dose of NaB group (58.3%, and 25.0% vs. 0, P < 0.01). At the 24th week, the tumor incidence was 95.0% in DMH alone group, 45.0% in DMH plus low dose of NaB group, and 15.0% in DMH plus high dose of NaB group; the differences among the 3 groups were significant (P=0.01, P < 0.01). No tumor was observed in control group and high dose of NaB group. There was no difference in the general condition, body weight increasing, and liver and renal functions of the mice between control group and high dose of NaB group (P > 0.05); no pathologic changes in liver, kidney, lungs, and pancreas were observed in the mice in high dose of NaB group., Conclusion: NaB could inhibit DMH-induced tumorigenesis of colorectal cancer in mice with no obvious toxicity.

Objective: The research on flavonoid in the recent years is extensive, such as Soybeans flavone, Baicalensis flavone, Epimedium flavone. Experiments show the effects of flavonoid is closely related to human health. There are a lot of reports about Ginkcobiobal flavone. In order to make further progress research on ginlcgobiobal flavone, we sum up the articles and reports on ginlcgobiobal flavone in the recent years., Method: To searche the articles about ginlcgobiobal flavone studies in the past five years., Result: Ginlcgobiobal flavone is not only a vasodilator, but also has the effects of anti-inflammation, analgesia, lowering blood lipids, preventing senile and inhibiting tumor, treating leukaemia, regulating gene and biotransformation., Conclusion: Ginlcgobiobal flavone has the potential value for drug research and development.

The effects of acidity and temperature on the fluorescent characteristics of N-N-bis-(O-Carboxylphenyl)-Oxamide (OBBE) have been studied in details. And the quantum efficiency of fluorescence has been measured. In a pH 8-9.5 buffer medium of H3BO3-NaOH, OBBE has a maximum excitation wavelength at 210 nm and a maximum emission wavelength at 395 nm. The nitrate reacts with OBBE and quenches the fluorescent intensity of OBBE. Thus a new sensitive method using the quenching of synchronous fluorimetry has been developed for the direct determination of nitrate in water. The linear calibration curve was obtained in the range of 0.0028 and 0.16 mg.L-1, the detection limit was 0.0028 mg.L-1. The proposed method has been applied to the determination of nitrate in water with satisfactory results.