Objective To observe the effect of different energy levels of pulsed Nd∶YAG laser irradiation on the changes of NO and NOS levels in ulcer tissue of oral ulcer model.Methods Forty-eight Sprague-Dawley rats were inflicted with oral ulcer,and then randomly and equally assigned to 6 groups,that is,oral ulcer group,1% iodine glycerin group and the rest 4 groups receiving pulsed Nd∶YAG laser irradiation at 1.5 W 40 mJ,1.5 W 60 mJ,1.5 W 80 mJ or 1.5 W 100 mJ(once per day,for 3 consecutive days).The other 8 rats served as normal control.In 24 h after last treatment,4 rats from each group were sacrificed and their cheek pouches were taken out for NO and NOS levels in the mucosal tissue by spectrophotomentry.Ulcer healing were observed 24 h after the last treatment for 8 consecutive days.The efficiency of Nd∶YAG laser irradiation at different powers were evaluated.Results Irradiation groups had significantly shorter healing time compared with iodine glycerin group.Level of NO and NOS activity in 1.5 W 60 mJ and 1.5 W 80 mJ groups was evidently lower than the ulcer group(P

BACKGROUND: Screening using low-dose computed tomography (LDCT) is a more effective approach and has the potential to detect lung cancer more accurately. We aimed to conduct a meta-analysis to estimate the accuracy of population-based screening studies primarily assessing baseline LDCT screening for lung cancer. METHODS: MEDLINE, Excerpta Medica Database, and Web of Science were searched for articles published up to April 10, 2022. According to the inclusion and exclusion criteria, the data of true positives, false-positives, false negatives, and true negatives in the screening test were extracted. Quality Assessment of Diagnostic Accuracy Studies-2 was used to evaluate the quality of the literature. A bivariate random effects model was used to estimate pooled sensitivity and specificity. The area under the curve (AUC) was calculated by using hierarchical summary receiver-operating characteristics analysis. Heterogeneity between studies was measured using the Higgins I2 statistic, and publication bias was evaluated using a Deeks' funnel plot and linear regression test. RESULTS: A total of 49 studies with 157,762 individuals were identified for the final qualitative synthesis; most of them were from Europe and America (38 studies), ten were from Asia, and one was from Oceania. The recruitment period was 1992 to 2018, and most of the subjects were 40 to 75 years old. The analysis showed that the AUC of lung cancer screening by LDCT was 0.98 (95% CI: 0.96-0.99), and the overall sensitivity and specificity were 0.97 (95% CI: 0.94-0.98) and 0.87 (95% CI: 0.82-0.91), respectively. The funnel plot and test results showed that there was no significant publication bias among the included studies. CONCLUSIONS Baseline LDCT has high sensitivity and specificity as a screening technique for lung cancer. However, long-term follow-up of the whole study population (including those with a negative baseline screening result) should be performed to enhance the accuracy of LDCT screening.
Humans ; Adult ; Middle Aged ; Aged ; Lung Neoplasms/diagnostic imaging* ; Early Detection of Cancer ; Sensitivity and Specificity ; Mass Screening ; Tomography, X-Ray Computed