Objective To investigate the visual acuity improvement and related factors for myopia after femtosecond flap excimer laser surgery. Methods 72 myopic patients (129 eyes) in our hospital between January 2010 and December 2013 were chosen. The patients all received femtosecond flap excimer laser surgery. The visual acuity improvement after surgery was observed, and the influencing factors were analyzed. Results The distance vision (VA), near vision (NVA) and best corrected visual acuity (BCVA) significantly increased before surgery (P<0.05). Logistic regression analysis showed that preoperative BCVA, NVA, axial length, cutting ratio, axial length and time of near vision were the affecting factors of visual acuity (P<0.05). Conclusion Femtosecond flap excimer laser surgery for myopia has significant effect , but the preoperative visual acuity was affected by BCVA , NVA, cutting ratio, axial length and time of near vision.

A non-reduced SDS-PAGE purity method for quantitation of conbercept fragments was established based on gel screening, comparison of gel imaging system, linearity range of main band, screening of destaining conditions. The results indicated that the bands could be separated effectively with good clearness and flatness on 4%-15% gradient concentration gel, the peaks of all bands could be separated from baseline using high-distinguishability gel imaging system, the signal intensity of a main band had shown a good linearity with ≤ 3 μg of loading amount, and that the destaining was set as a total of ≤ 3 h with exchanging 100 mL destaining buffer every 60 min. The established non-reduced SDS-PAGE method could demonstrate the purity of conbercept more objectively. After validation, the established non-reduced SDS-PAGE method was submitted to FDA in the form of supplementary materials, which laid a quality basis for the direct entry of conbercept to the clinical Ⅲ study in the United States.

Near-infrared spectroscopy (NIRS) combined with chemometrics can achieve rapid detection in process analysis. After variable selection, the redundant information is effectively removed and the characteristic variables related to the response values are selected. Compared with global model, the complexity is significantly reduced and the prediction accuracy is also improved. In this study, near-infrared spectroscopy analysis combined with different variable selection methods was applied to achieve the rapid detection of baicalin in the extraction process of Scutellaria baicalensis. Data sets were divided based on sample set portioning based on joint x-y distance (SPXY) method. Competitive adaptive weighted resampling method (CARS), random frog (RF) and successive projections algorithm (SPA) were applied to variable selection. Partial least squares (PLS) models were constructed based on above three methods, and the prediction results were compared. After CARS, RF and SPA method, 92, 10 and 17 variables were screened out respectively. According to the performance of the models, CARS method is found to be more effective and suitable than RF and SPA. Furthermore, the characteristic variables selected by CARS method have a better correspondence with the chemical structure of baicalin. The root mean square error (RMSEC) of the calibration set and the root mean square error (RMSEP) of the prediction set are 0.528 2 and 0.720 2 respectively. Compared with the global PLS model, the correlation coefficient of the calibration set (Rc) is increased to 0.979 9 from 0.917 0, and the relative standard errors of prediction (RSEP) is reduced to 5.59% from 10.58%.

Objective: To analyze correlation of occupational hydrogen fluoride exposure to low doses of bone metabolism index through occupational epidemiological investigation and benchmark dose calculation. Methods: In May 2021, using cluster sampling method, 237 workers exposed to hydrogen fluoride in a company were selected as the contact group, and 83 workers not exposed to hydrogen fluoride in an electronics production company were selected as the control group. The external exposure dose and urinary fluoride concentration, blood and urine biochemical indicators of the workers was measured.The relationship between external dose and internal dose of hydrogen fluoride was analyzed. The external dose, urinary fluoride was used as exposure biomarkers, while serum osteocalcin (BGP), serum alkaline phosphatase (AKP) and urinary hydroxyproline (HYP) were used as effect biomarkers for bone metabolism of hydrogen fluoride exposure. The benchmark dose calculation software (BMDS1.3.2) was used to calculate benchmark dose (BMD) . Results: Urine fluoride concentration in the contact group was correlated with creatinine-adjusted urine fluoride concentration (r=0.69, P=0.001). There was no significant correlation between the external dose of hydrogen fluoride and urine fluoride in the contact group (r=0.03, P=0.132). The concentrations of urine fluoride in the contact group and the control group were (0.81±0.61) and (0.45±0.14) mg/L, respectively, and the difference between the two groups was statistically significant (t=5.01, P=0.025). Using BGP, AKP and HYP as effect indexes, the urinary BMDL-05 values were 1.28, 1.47 and 1.08 mg/L, respectively. Conclusion: Urinary fluoride can sensitively reflect the changes in the effect indexes of biochemical indexes of bone metabolism. BGP and HYP can be used as early sensitive effect indexes of occupational hydrogen fluoride exposure.
Humans ; Fluorides/adverse effects* ; Hydrofluoric Acid ; Benchmarking ; Biomarkers ; Occupational Exposure/adverse effects*

Aiming at the phenomenon of heavy metal Cd exceeding the standard of Chuanxiong medicinal materials,the accumulation of 12 inorganic elements,including heavy metals,in Ligusticum chuanxiong was studied in this paper. It was found that the contents and distribution of most inorganic elements in the stems and leaves of L. chuanxiong were higher than those in the rhizomes at seedling and shooting stages. The content of most elements in rhizome reached the highest at harvest stage,and the distribution ratio of some elements in rhizome was higher than that in stem and leaf at harvest stage. But rhizome,stem and leaf of L. chuanxiong have relatively stable absorption capacity and enrichment effect on different elements,and are less affected by growth period and position. Rhizomes and stems and leaves of L. chuanxiong were enriched with Cd,and stems and leaves also accumulated Pb at seedling stage and stem stage. The absorption capacity of Pb in stems and leaves of L. chuanxiong was higher than that of rhizomes,and the ability of absorbing Cd was less than that of rhizomes at harvest time. The total uptake of Cd and Pb by L. chuanxiong decreased with the prolongation of growth time,but the proportion of Cd and Pb in rhizome increased,so that the content of Cd and Pb increased with the prolongation of growth time.
Cadmium ; analysis ; Drugs, Chinese Herbal ; chemistry ; Ligusticum ; chemistry ; Metals, Heavy ; analysis ; Plant Leaves ; chemistry ; Plant Stems ; chemistry ; Rhizome ; chemistry