Objective To know the contamination situation of the centralized air conditioning-ventilating systems in hotels in Shenzhen City, Guangzhou province and to ensure the indoor air quality when the centralized air conditioning-ventilating systems were at working. Methods 22 hotels were selected to determine the total count of bacteria and fungi in internal surface of pipes and air blow, the dust volume of internal surfaces of pipes, inhalable particulate matter(PM10) in air blow, and Legionellae in cooling tower water. Results The eligibility percent of dust volume, the total number of bacteria and fungi in internal surface was 94.76 %, 95.71% and 91.90 % respectively,the eligibility percent of PM10, the total count of bacteria and fungi in air blow was 42.54%, 94.76% and 84.29% respectively, and the detected rate of Legionellae was 57.50%. Conclusion The pollution in some degrees has been observed in the centralized air conditioning-ventilating systems in hotels of Shenzhen City, so it is considered as the important measure to improve indoor air quality and ensure people health to strengthen management of centralized air conditioning-ventilating systems in the usage.

Objective To investigate the clinical efficacy of intravitreal ranibizumab injection combined with complex trabeculectomy in treatment of neovascular glaucoma. Methods Totally 38 patients(38 eyes) of neovascular glaucoma were divided into two groups of 19 cases in each randomly. Patients in treatment group were treateded with complex trabeculectomy after intravitreal injection 0. 05 mL ( 0.5 mg ) ranibizumab 4 - 7 days. Patients in control group were treateded with cyclocryotherapy. Visual acuity, intraocular pressure, iris neovascularization and complications were observed. Results The average intraocular pressure of preoperation and postoperation 1 month in treatment group were (6.5±1.7) kPa and (2.1±1.2) kPa.The difference of intraocular pressure before and after operation was significant. The average preoperative and postoperative intraocular pressure in control group were (6.7±1.9) kPa and (2.5±1.2) kPa . The postoprative intraocular pressure of treatment group was lower than that of control group, the difference was statistically significant( P< 0.05). Visual acuity and operative reaction after operation in treatment group were superior to those in control group. Conclusion Intravitreal injection of ranibizumab combined with complex trabeculectomy in treatment of neovascular glaucoma is safe and effective and worth in clinical application.

Objective To explore the related factors of contrast agent leakage in CT enhanced scanning and to find out its preventive measures.Methods The clinical data of 46 patients with iodine leakage in the CT enhanced scanning during 2015 were retrospectively analyzed.Results The leakage rate had statistically significant difference between different patient's genders(P＜0.05).The leakage rate was related to the age of the patients(P＜0.01).The leakage rate showed the increasing trend with the increase of injection rate(P＜0.05).The leakage rate was related to the concentration of the contrast agent(P＜0.05).The leakage rate had no increasing trend with the increase of injection dose(P=0.675).The leakage rate was related to the years of injection nurses engaging this working(P＜0.01).Conclusion The leakage rate of female patients was higher than that of male.The older the patients,the greater the contrast agent concentration,the faster the injection rate and the lower the working years of injection nurses,the greater the leakage rate.

Objective:To assess the three-dimensional dose distribution in radiotherapy plans using the structural similarity index(SSIM), compare the performance of SSIM with commonly used quality assessment indices, and develop a SSIM-based quality assessment method of multiple prescribed doses.Methods:The SSIM was introduced to providea quality score of various voxels by comparing actual and ideal three-dimensional dose data and combining the spatial location information of the voxels. Then the average value in a region of interest (ROI) was calculated as the quality score of the region. Fifty-three cases of cervical cancer were selected to analyze the correlation of the SSIM with the uniformity index (HI), conformity index (CI) of the dose distribution in various ROIs and to explore the capability of the SSIM to reflect the uniformity and conformity of dose distribution.Two types of quality defects were individually introduced into two of 53 radiotherapy plans. Then the two plans were compared with normal plans to characterize the response of the SSIM.Results:There was no correlation between HI and SSIM in positive lymph nodes(PGTVnd) due to the decrease in the HI sensitivity, while there was a significant negative correlation between them in regions where PGTVnd was removed from the planning target volume(PTV, R=-0.86, P<0.01). Meanwhile, there was a significant positive correlation between CI and SSIM in PGTVnd ( R=0.83, P<0.01). Therefore, the SSIM can be used to identify the artificial design defects in plans by determining abnormal dose gradients. Conclusions:Apart from reducing the defects of previous assessment parameters, the SSIM has the capability to assess the quality of radiotherapy plans by combining the uniformity and conformity of dose distribution and can provide accurate feedback on the spatial locations of quality defects.

AIM: To compare the differences in the efficacy and safety of combination of intravitreal dexamethasone(Ozurdex)and ranibizumab or monotherapy of ranibizumab in eyes with macular edema secondary to retinal vein occlusion(RVO-ME).METHODS: Patients diagnosed with non-ischemic RVO-ME by fluorescein fundus angiography in our hospital from June 2020 to December 2022 were selected. All patients were initially treated with intravitreal injection of ranibizumab(0.5 mg), and 42 patients(42 eyes)who had central retinal thickness(CRT)≥300 μm after 2 wk were included. They were randomly divided into combined treatment group and monotherapy group. The combined treatment group(21 eyes)received Ozurdex intravitreal injection immediately, while the monotherapy group(21 eyes)was treated with ranibizumab intravitreal injection by 3+pro re nata(PRN). The changes of best corrected visual acuity(BCVA), CRT, and intraocular pressure before and at 2 wk, 1, 2, 3, 4, 5, and 6 mo after treatment were recorded, and the ocular or systemic complications were observed.RESULTS:The BCVA and CRT of all patients at 2 wk, 1, 2, 3, 4, 5, and 6 mo after treatment were significantly better than those before treatment(all P<0.01). There were statistical significance in the BCVA and CRT between two groups at 2 and 3 mo after treatment(all P<0.05). The most significant increase of BCVA in the combined treatment group occurred at 2 mo after treatment. The mean recurrence time of macular edema in the monotherapy group was 1.45±0.53 mo, with 4.21±0.78 injection times of ranibizumab. None of the patients showed serious complications after treatment. The most common complications in the combined treatment group were subconjunctival hemorrhage and elevated intraocular pressure, which were manageable with topical ocular hypotensive agents, and no patient required antiglaucoma or cataract surgery.CONCLUSION: Compared with monotherapy of ranibizumab, intravitreal injection of dexamethasone combined with ranibizumab can significantly improve the visual acuity and effectively reduce the macular edema in the treatment of RVO-ME, with a long duration of efficacy and less intravitreal injection of drugs.

Objectives:This study aimed to evaluate the effect of the strategies on COVID-19 outbreak control in Shenzhen, and to clarify the feasibility of these strategies in metropolitans that have high population density and strong mobility.Methods:The epidemic feature of COVID-19 was described by different phases and was used to observe the effectiveness of intervention. Hierarchical spot map was drawn to clarify the distribution and transmission risk of infection sources at different time points. The Susceptible-Exposed-Infectious-Asymptomatic-Recovered model was established to estimate case numbers without intervention and compare with the actual number of cases to determine the effect of intervention. The positive rate of the nucleic acid test was used to reflect the risk of human exposure. A survey on COVID-19 related knowledge, attitude and behaviors were used to estimate the abilities of personal protection and emergency response.Results:The epidemic of COVID-19 in Shenzhen experienced the rising, plateau and decline stage. The case number increased rapidly at the beginning, with short duration of peak period. Although the epidemic curve showed human-to-human transmission, the "trailing" was not obvious. From the spot map, during the intervention period, the source of infection was widely distributed. More cases and higher transmission risk were observed in areas with higher population density. After the effective intervention measures, both infection sources and the risk of transmission decreased. After compared with the estimated case numbers without intervention, actual number proved the COVID-19 control strategies were effective. The positive rate of nucleic acid test for high risk populations decreased and no new cases reported since February 16. Shenzhen citizens had high knowledge, attitude and behavior level, and high protection ability and emergency response.Conclusions:Although the response initiated by the health administration department played a key role at the early stage of the epidemic, it was not enough to contain the outbreak of COVID-19. The first-level emergency response initiated by provincial and municipal government was effective and ensured the start of work resumption after the Spring Festival. Metropolitans like Shenzhen can also achieve the goals of strategies and measures for containment and mitigation of COVID-19.

Objective To establish the analytical performance specifications(APS)for routine items of biochemical inspection based on the external quality assessment(EQA)and internal quality control(IQC)data.Methods The EQA data and IQC data of routine items of biochemistry inspection in clinical laboratory center of national health commission from 2021 to 2023 were collected from the Department Clinical Laboratory of Traditional Chinese Medicine Hospital of Chengdu Pidu District.Comparing the percentage difference of the EQA data and the IQC in control imprecision[expressed as the coefficient of variation(CV)]data with the 3-level evaluation criteria derived based on biological variation(BV),the percentage pass rate of EQA data and the pass rate of CV under control were calculated,so as to achieve the quality target of APS with 80％or more as the quality control product of this level as the routine biochemical test items of the laboratory.For the inspection items that did not reach BV standard APS or were not applicable to meet the standard,the APS would be set to the WS/T 403-2012 industry standard or based on current technical level.Results TEa/allowable CV of biochemical inspection items were as follows:Potassium(K)2.4％/1.9％,Sodium(Na)4.0％/0.9％,Chloride(Cl)4.0％/0.9％,Calcium(Ca)3.4％/1.8％,Phosphate(P)9.6％/1.9％,Magnesium(Mg)3.8％/2.0％,Glucose(Glu)6.1％/2.3％,Creatinine(Crea)3.9％/2.2％,Urea(Urea)8.6％/3.3％,Total protein(TP)4.9％/2.0％,Albumin(Alb)3.3％/1.9％,Total bilirubin(TBil)6.3％/2.4％,Alanine transaminase(ALT)9.3％/2.9％,Asparpartate transaminase(AST)6.2％/2.1％,γ-glutamyl transferase activity(GGT)9.2％/2.1％,Lactate dehydrogenase(LDH)6.8％/2.2％,Alkaline phosphatase(ALP)7.2％/3.3％,Total cholesterol(TC)of 8.3％/2.6％,Triglyceride(TG)12.9％/4.9％,Amylase(AMY)5.9％/1.6％,Creatine kinase(CK)4.3％/1.6％and Uric acid(UA)2.9％/1.0％.Conclusion The APS set based on BV or current technical level can be used as a quality target for routine laboratory clinical biochemistry testing programs,and the laboratory can select the suitable APS according to the actual situation.