Objective To investigate the therapeutic effect of non-invasive positi e pressure ventilation (NIPPV) in the treatment of patients with acute exacerbations of chronic obstructive pulmonary disease(AECOPD).Methods 68 AECOPD patients with type Ⅱ repiratory failure were randomly divided into control group and treatment group.The control group was treated by conventional therapy alone and the treatment group was given conventional therapy combined with NIPPV.The levels of power of hydrogen (pH),partial pressure of carbon dioxide in artery(PaCO2),arterial oxygen tension(PaO2),heart rate and repiratory rate were compared between the two groups.The mean length of patient stay,the frequency of tracheal intubation and the hospital mortality were analyzed after discharge from the hospital.Results Before treatment,the arterial blood gas analysis showed that the pH,PaCO2 and PaO2 had no significant differences between the two groups(all P ＞ 0.05).After treatment,compared with the control group,the levels of pH,PaCO2 and PaO2 were obviously improved(all P ＜0.05).The mean length of patients stay in the treatment group was significantly shorter than the control group(P ＜ 0.05).The frequency of tracheal intubation of the treatment group was significantly lower than the control group(P ＜ 0.05).The hospital mortality was lower in the treatment group,but the difference between the two groups was not significant (P ＞ 0.05).Conclusion NIPPV for treating the AECOPD can improve the arterial blood gas analysis,decrease the need of tracheal intubation and shorten hospitalization time.

Objective:To study the characteristics of the lens turbidity after long-term exposure to low intensity 635nm laser.Methods:Cluster sampling method was adopted to select 812 employees in a laser leveler workshop in a city of Guangdong Province from January 2014 to December 2018. They were divided into the control group, diffuse reflection (DR) group and direct vision (DV) group for retrospective observation and analysis of lens turbidity. The laser irradiation intensity of each group was investigated, the position and shape of lens opacity were analyzed, and the influencing factors were statistically analyzed with the repeated measurement data of dichotomy.Results:The laser irradiance and radiant exposure of DV group were between 0.72×10 -4 and 9.92×10 -4 mW/cm 2 and between 2.61×10 -2 and 1.53 J/cm 2, respectively. The subjects were mainly diagnosed with lens turbidity lesion, especially for the DV group. Most of lesions occurred in the pole and periphery of the anterior cortex. The lesions exhibited multipoint patterns with greyish white color. The turbidity rates in DV group (before work and work for 1, 2, 3 years) were 0%, 1.99% (8/402) , 4.98% (20/402) and 6.72% (27/402) , respectively, in the order of observation points. The statistical analysis of single factor effect showed that the turbidity rate was higher in DV group and higher in the second year in the DV group ( P<0.01) . Multi-factor analysis of the laser effect on the lens showed that the main effect between groups, between the observation point were statistically significant ( P<0.05) , but no statistical significance in the interaction between group×observation points ( P>0.05) . Conclusion:Lens turbidity lesion can be caused by long-term exposure to low intensity 635 nm laser, so the product safety classification should be strictly strengthened. It is necessary to strengthen the protection of laser photochemical damage in the production process.

This article analyzed the clinical data of a patient with occupational chemical poisoning in a fabric processing workshop in August 2020, and carried out occupational hygiene investigation and testing. The patient went to the doctor because of painless progressive vision loss in both eyes, and was clinically diagnosed with methanol poisoning optic neuropathy in both eyes. The glue, solvent, washing machine water, and curing agent used in the workshop were used for qualitative analysis of volatile organic components, and methyl acetate was all detected. Esters, the relative percentages were 42.56%, 66.67%, 46.43%, and 41.63%, respectively. Therefore, it was judged that the patient was occupational acute methyl acetate poisoning, the enterprise should strengthen the awareness of safe production and enhance the occupational hygiene knowledge and self-protection awareness of workers.

Objective:To study the characteristics of the lens turbidity after long-term exposure to low intensity 635nm laser.Methods:Cluster sampling method was adopted to select 812 employees in a laser leveler workshop in a city of Guangdong Province from January 2014 to December 2018. They were divided into the control group, diffuse reflection (DR) group and direct vision (DV) group for retrospective observation and analysis of lens turbidity. The laser irradiation intensity of each group was investigated, the position and shape of lens opacity were analyzed, and the influencing factors were statistically analyzed with the repeated measurement data of dichotomy.Results:The laser irradiance and radiant exposure of DV group were between 0.72×10 -4 and 9.92×10 -4 mW/cm 2 and between 2.61×10 -2 and 1.53 J/cm 2, respectively. The subjects were mainly diagnosed with lens turbidity lesion, especially for the DV group. Most of lesions occurred in the pole and periphery of the anterior cortex. The lesions exhibited multipoint patterns with greyish white color. The turbidity rates in DV group (before work and work for 1, 2, 3 years) were 0%, 1.99% (8/402) , 4.98% (20/402) and 6.72% (27/402) , respectively, in the order of observation points. The statistical analysis of single factor effect showed that the turbidity rate was higher in DV group and higher in the second year in the DV group ( P<0.01) . Multi-factor analysis of the laser effect on the lens showed that the main effect between groups, between the observation point were statistically significant ( P<0.05) , but no statistical significance in the interaction between group×observation points ( P>0.05) . Conclusion:Lens turbidity lesion can be caused by long-term exposure to low intensity 635 nm laser, so the product safety classification should be strictly strengthened. It is necessary to strengthen the protection of laser photochemical damage in the production process.

This article analyzed the clinical data of a patient with occupational chemical poisoning in a fabric processing workshop in August 2020, and carried out occupational hygiene investigation and testing. The patient went to the doctor because of painless progressive vision loss in both eyes, and was clinically diagnosed with methanol poisoning optic neuropathy in both eyes. The glue, solvent, washing machine water, and curing agent used in the workshop were used for qualitative analysis of volatile organic components, and methyl acetate was all detected. Esters, the relative percentages were 42.56%, 66.67%, 46.43%, and 41.63%, respectively. Therefore, it was judged that the patient was occupational acute methyl acetate poisoning, the enterprise should strengthen the awareness of safe production and enhance the occupational hygiene knowledge and self-protection awareness of workers.

OBJECTIVE: To observe the effect of n-hexane subchronic exposure on the serum level of neuron specific enolase(NSE), neurofilament light chain protein(NF-L) and nerve growth factor(NGF) in rat, and to explore the feasibility of using NSE, NF-L and NGF as biomarkers of n-hexane neurotoxicity. METHODS: Specific pathogen free male SD rats were randomly divided into control group and low-, medium-and high-dose exposure groups, with 6 rats in each group. Rats in the low-, medium-and high-dose exposure groups were given n-hexane solution at doses of 168, 675 and 2 700 mg/kg body mass, respectively, while rats in the control group were gavaged with 0.9% sodium chloride solution, once a day, 5 days a week for 6 weeks. At week 0, 2, 4, and 6 of exposure, the body mass of the rats was weighed, the gait scores were performed, and the serum levels of NSE, NF-L, and NGF were detected.RESULTS: Body mass, gait score and serum levels of NSE and NF-L in rats were statistically significant in terms of the n-hexane exposure dose and exposure time(P<0.01). At the 6 th week of n-hexane exposure, the body mass of the three dose exposure groups was lower than that of the control group(P<0.05), and the gait score was higher than that of the control group(P<0.05). Moreover, the abnormal gait of the rats showed a dose-effect relationship with the increasing n-hexane poisoning dose. At week 2, 4 and 6, the serum levels of NSE and NF-L in these three dose exposure groups were higher than that in the control group(P<0.05). In addition, the serum level of NF-L in rats in the medium-and high-dose exposure groups increased with the n-hexane exposure time increasing and showed a time-effect relationship(P<0.05). The level of serum NGF in rats was statistically significant in the main effects of n-hexane dose and duration of exposure(P<0.05). The serum NGF level in the high-dose exposure group was lower than that in the control group, the low-dose and medium-dose exposure groups(P<0.05). NGF level in serum of rats at week 6 was lower than that at week 0, 2 and 4(P<0.05). CONCLUSION: Both NSE and NF-L in serum can be used as biomarkers for the early effect of n-hexane on peripheral nerve injury. The feasibility of using serum NGF as a biomarker for the early effect of n-hexane on peripheral nerve injury warrants further investigation.

Objective: To analysis pathogenic conditions and pathogenic characteristics of organic fluorosis caused by applying of anti-fingerprint coating material on touch screen glass of the mobile phone. Methods: To collect clinical data and analyze the causes and pathogenic characteristics of poisoning through surveying occupational health, detecting occupational hazards in the workplace, collecting clinical data and diagnosing of occupational diseases. 6 employees in workshop 1 of packaging were as the organic fluorine exdposed group, and 16 employees in other workshops were as the non-exposed group. Results: Organic fluorine chemicals (perfluoro-1, 3-dimethylcyclohexane, hexadecafluoroheptane, perfluoro-hexane, perfluoromethy lopentane, perfluoro-2-methyl-2-pentene, etc.) can be volatilized by spraying and baking of anti-fingerprint nano-coating material on touch screen. The relative percentage of volatile components in air is 85.65%. Four cases of acute poisoning were caused by organic fluorosis deposited in a dustless air conditioning workshop with poor ventilation.The clinical manifestations of the patients were acute bronchitis, pulmonary edema and/or myocarditis. The average concentration of urine fluorine in the organic fluorine exposed group was 13.7± 4.4 mmol/mol creatinine, which was 4-5 times higher than that of other non-organic fluorine exposed groups. The difference of urine fluorine level between the organic fluorine exposed group and non exposed group was statistically significant (P<0.01) . The main indicators were abnormal for the blood oxygen saturation of finger pulse under suction air, leukocytes, neutrophils, monocytes, hypersensitivec-reactive protein, procalcitonin, l-lactate dehydrogenase, forebrain diuretic natriuretic peptide, hypersensitive troponin T in the four cases. One case was myocardial ischemia, four cases had bilateral lung symmetrically exudative lesions, one case was accompanied by a small amount of pleural pericardial effusion. Conclusion Acute organofluorine poisoning can caused by the applying of the fingerprint nano-coating material on touch screen of the mobile phone. Attention should be paid to occupational poisoning caused by the applying of the small molecular perfluoroalkanes (olefins) in new industries, new processes and new materials.