Objective To investigate the expression of monocyte chemoattractant protein-1(MCP-1)and CCR2 in peripheral blood and pleural fluid of tuberculous pleurisy patients.Methods Flow cytometry was used to detect the expression of CCR2 in the peripheral blood mononuclear cell and pleural fluid cell of tuberculous pleurisy patients;ELISA was used to detect the content of MCP-1 in serum and pleural fluid.Results MCP-1 in surem and pleural fluid and CCR2 in the peripheral blood mononuclear cell and pleural fluid cell of tuberculous pleurisy patients was significantly higher than that of the healthy normal controls[MCP-1:(340.8±220.8)and(9.0±3.8)ng/L,P＜0.01;CCR2(18.2±10.1)%and(6.9±3.5)%,P＜0.05];Both MCP-1 and CCR2 were detected in pleural fluid and both of them were positivley correlated(r=0.227,P＜0.05).Conclusion The expression of MCP-1 and CCR2 in peripheral blood of tuberculous pleurisy patient are significantly elevated which are significance molecule participating in the pathogenesis of tuberculous pleurisy.

Objective To investigate the perception of Mandarin's tones by children with speech development disorders so as to provide a theoretical basis for clinical rehabilitation.Methods Thirty children with speech development disorders (DPDs) aged 4 to 6 were matched with 30 healthy counterparts as a control group.Both groups underwent the tone perception experiment,which included tone identification and discrimination tasks.The speech stimuli were 11 computer-simulated voices expressing a continuum of sounds from Mandarin speech ranging from /bá/ to /bà/.The two groups were compared in their ability to identify and differentiate the tones.Results Both groups showed typicalS-shaped identification curves in a category pattern.The category boundaries of the control group were between stimulus steps 6 and 7,significantly different from those of the experimental group where the boundary fell between stimulus steps 5 and 6.On the distinguishing curve,both groups presented obvious peak values.The stimulus steps of the peaks and the crossing points of the identification curves were consistent.In addition,the average ahsolnte value (b1) of the identification curve and the peaks' degree of steepness (DP) of the DPD group's distinguishing curve were significantly lower than those of the control group.At the same time,the average boundary width (Wcb) was significantly higher than that of the control group.Conclusion Children with speech development disorders perceive Mandarin tones with categories different from those of normal children.They may have difficulty in perceiving tones,which might be an important factor leading to pronunciation errors.

Objective:To investigate the application value of third-generation dual-source CT(3-G DSCT) low-dose scan mode combined with iterative reconstruction technology in the screening of COVID-19 and to evaluate the radiation dose.Methods:One hundred and twenty patients suspected of COVID-19 from December 2019 to February 2020 were retrospectively analysed and randomly divided into two groups (test group and conventional group, 60 patients in each). The parameters for test group included 3-G DSCT, Turbo Flash scan mode, CARE kV, with reference 90 kV, pitch 2.0, and ADMIRE algorithm, while those parameters for conventional group included the 128-slice CT, conventional spiral scan mode, 120 kV, pitch 1.2, and FBP algorithm. The CT values of aorta, spinal posterior muscle, and subcutaneous fat, the aortic noise, signal-to-noise ratio (SNR), and contrast noise ratio (CNR) were compared to evaluate the image quality between two groups. Two experienced doctors scored the image quality using a double-blind method, and compared the CT dose index volume (CTDI vol), dose-length product (DLP), and effective dose ( E) of the two groups. Results:The CT value of the aorta and spinal posterior muscle and the aortic SNR in the test group were (45.38±4.77), (53.41±8.44) HU, and 2.82±0.59, and significantly higher than those in the conventional group [(39.68±6.26), (42.66±6.32) HU, 2.58±0.61, t=5.608, 7.897, 2.162, P<0.05]. The aortic noise, CNR and subjective scores between the two groups had no significant difference( P>0.05). The CTDI vol, DLP, and E in the test group were (3.09±1.02) mGy, (107.57±32.81) mGy·cm, (1.51±0.46) mSv, significantly lower than those in the conventional group [(7.00±1.80) mGy, (261.65±73.93) mGy·cm, (3.66±1.03) mSv; t=-14.680, -14.756, -14.756, P<0.05]. Conclusions:In the screening of COVID-19, using low-dose scanning mode of 3-G DSCT combined with iterative reconstruction technology would provide diagnostic quality images and meanwhile effectively reduce the radiation dose and improve the SNR of the image.

Objective:To explore a low dose CT scanning method on novel coronavirus (COVID-19) pneumonia based on infection prevention and control.Methods:A total of 140 patients with confirmed novel coronavirus pneumonia in Xiehe hospital from January 20, 2020 to February 28, 2020 were undertaken CT scan and divided into low dose group and conventional dose group. The patients in low dose group(120 kV, 31 mAs) consisted of mild type(51), severe type(15) and critically ill type(4); and those in conventional dose group(120 kv, adaptive milliampere second) consisted of mild type(48), severe type(17) and critically ill type(5). The effective radiation dose, SNR and CNR of CT scan were compared between two groups. A senior and a middle radiologist made the image subjective quality scores, respectively.Results:The effective dose in low dose group was lower than that of conventional dose group( t=-48.343, P<0.05). There was no significant difference in SNR and CNR between two groups( P>0.05). For severe and critically ill patients, the score in low dose group was significantly lower than that in conventional dose group( t=-2.781, P<0.05). There was no significant difference in scores between two groups for mild patients( P>0.05). Conclusions:Low-dose CT scanning could meet the image quality needs for patients with COVID-19 and meanwhile significantly reduce the radiation dose.