Objective To evaluate the application of flexible thoracoscopy in the diagnosis of pleural effusion.Methods Thoracoscopy was performed in 20 pleural effusion patients in our hospital from May to December 2007.Biopsies were performed in 16 patients,not in the other 4 patients since difinite diagnosis had been reached before thoracoscopy.Results Rate of accurate diagnosis via thoracoscopy was 93.75%(15/16).Results Of biopsy were as follows:adenocarcinoma 8 cases,squamous carcinoma 1 case,adenosquamous carcinoma 1 case,malignant pleural effusion 1 case,tuberculous pleuritis 4 cases,malignant mesothelioma 3 cases,chronic suppurative pleuritis 1 case,failed diagnosis 1 case.Presentations of lesions under thoracoscope were as follows:diffused miliary nodules 10 cases(10/20),multiple mass 7 cases(7/20),fibrous compartmentation or conglutination 9 cases(9/20).There were no severe complications.Conclusion Flexible medical thoracoscopy is a safe and efficient method of etiologic diagnosis of pleural effusion.

Objective:Based on the specific cleavage and non-specific "trans-cleavage" activities of the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein(CRISPR/Cas13), we established a visually amplification-free rapid detection technique of 2019-nCoV nucleic acid. This technique is easily processed with a low detection limit and good specificity.Methods:According to the 2019-nCoV gene sequence, specific CRISPR RNAs were screened and designed by bioinformatics analysis, and then synthesized as universal signal-strained RNA transcription targets in vitro to establish and optimize the reaction system. Moreover, the 2019-nCoV pseudoviral nucleic acid was used as a standard substance to evaluate the detection limit. A total of 65 positive samples were collected from various 2019-nCoV variants, while 48 negative samples included other clinically common respiratory pathogens, such as influenza A virus, influenza B virus, human parainfluenza virus, Klebsiella pneumonia, etc. All samples were tested by quantitative PCR (qPCR), digital PCR, and the method established in this study. The sensitivity and specificity of the newly established method were analyzed and evaluated. Results:With the newly established technique, the detection time for 2019-nCoV nucleic acid could be minimized to 6 minutes. In addition, the detection limit was 14 copies/μl when assisted by the displaying instrument, whereas it increased to 28 copies/μl with the naked eye. This technique had a sensitivity and specificity of 98.5% (66/67) and 100% (46/46) respectively, showing no statistically significant difference compared to the gold standard qPCR( P=1). Conclusions:This study has successfully established a CRISPR/Cas13a-based visually rapid detection technique for 2019-nCoV nucleic acid. This technique offers the advantages of a simple process, convenient operation, low environmental operating requirements, a detection limit close to qPCR, and a strong potential for on-site testing applications.