Dynamic renal imaging studies were performed in 132 patients using 99m Tc DTPA and 131 I OIH. Effective renal plasma flow(ERPF) and glomerular filtration rate(GFR) was obtained. GFRs were calculated with 2 background regions of interest(ROI),conventional subrenal areas(SB) and suprarenal areas(SP). The relative renal functions(RR) obtained by GFRs determination was significantly higer compared with that by ERPF. These results suggested that the RR of impaired kidney determined by GFR(SB) was obviously higher than that assessed by ERPF. Higher coefficient( r value) was gotten with GFR(SP) than with GFR(SB).Results suggested that the GFR obtained with conventional subrenal background ROI might overestimate individual renal function of the poorly functional kidney and the GFR estimated by suprarenal background ROI might be more accurate.

Objective To evaluate the in vivo behaviour of the pulsed tablet in six scintigraphic studies.Methods The lag time and the anatomical position at the time of release were detected by scintigraphic evaluation.Results The different types pulsed release tablets all can achieve the lag time in vivo.Conclusion Scintigraphic study is the first considered method to evaluate the in vivo behaviour of the new formulation.

Objective To prepare quercetin nanocrystals,improve their dissolution rate,and investigate the effects of different stabilizer types and ratios on the stability of nanocrystals.Methods Quercetin nanocrystals were prepared by solvent ultrasonication,and three different stabilizers(polyvinylpyrrolidone-K30,poloxamer F188 and sodium dodecyl sulfate)were compared.The particle size was used as a screening index to investigate the stability of placement,the microscopic morphology of nanocrystals was characterized by scanning electron microscopy,infrared spectroscopy and X-ray diffraction,and the mechanism of action between stabilizers and nanocrystals was discussed.Results Through experimental screening,the results showed that povidone K30 had the best stable performance,the nanocrystals were also in the form of rod crystals,and the dissolution rate of nanocrystals was significantly higher than that of active pharmaceutical ingredients.Conclusion The type and amount of stabilizer will affect the stability of nanocrystals.

This study retrospectively analyzed the clinical data of four patients with malignant tumor-induced ureteral strictures admitted to our hospital. All patients successfully underwent ureteroscopic metal stent placement surgery under real-time ultrasound guidance, with a surgical duration of (64±33) minutes. Postoperatively, there was a creatinine decrease of (74±127) mmol/L. Only two cases experienced Clavien-Dindo grade I complications postoperatively. The stents were well positioned in all patients, with a postoperative hospital stay of (2.5±0.6) days. This surgical approach for malignant tumor-induced ureteral obstruction can compensate for the limitations of endoscopic visualization.

Objective:To investigate the clinical value of prospective ECG-gated high-pitch protocol scanning of third generation DSCT in the diagnosis of pediatric congenital heart disease (CHD).Methods:A total of 243 children with confirmed CHD who were expected to undergo surgical treatment were prospectively collected and randomly divided evenly into 3 groups, with first group for prospective ECG-gated high-pitch scanning in third generation DSCT (Flash 3rd), second group for prospective ECG-gated high-pitch scanning in second generation DSCT (Flash 2nd) and third group for prospective sequential scanning in third generation DSCT (Sequence 3rd). The SD value and SNR of aortic root and pulmonary artery of each child were recorded. The 5-point system is adopted with subjective scoring. Based on the result of operation, the diagnosis accuracy in 3 groups was analyzed. Results:The E values in Flash 3rd, Flash 2nd and Sequence 3rd group were 0.24 (0.19, 0.27), 0.11 (0.10, 0.14) and 0.44 (0.39, 0.48) mSv ( H=207.04, P<0.05), respectively. Subjective scores of group Flash 3rd and Sequence 3rd were significantly higher than that of group Flash 2nd [4 (4, 4) vs. 4(3, 4) vs. 3(3, 3), H=124.05, P<0.05] and no difference between these two groups. SD value of aortic root and pulmonary artery of group Flash 3rd and Sequence 3rd were significantly lower than that of group Flash 2nd( H= -40.27-33.38, P<0.05). SNR of aortic root and pulmonary artery of group Flash 3rd was significantly higher than that of group Flash 2nd and Sequence 3rd ( H=-0.90-51.42, P<0.05). Diagnosis accuracy of intracardiac malformation for group Flash 2nd was significantly lower than that of Flash 3rd and Sequence 3rd (77.7%, 90.9%, 88.9%, K=9.36, P<0.05), and there was no significant difference between the latter two groups. There was no difference in diagnosis accuracy of extracardiac malformation among 3 groups (88.6%, 94.8%, 92.2%, K=3.11, P=0.21). Conclusions:The prospective ECG-gated high-pitch scanning in third generation DSCT can take into account radiation dose and image quality, which has important clinical value in the diagnosis of CHD.

Objective:To explore the value of coronary CT angiography (CCTA) in the diagnosis of vulnerable plaques using intravascular ultrasound (IVUS) as the gold standard.Methods:A retrospective analysis was conducted on the clinical and imaging data of coronary artery disease patients who underwent both IVUS and CCTA examinations at Fuwai Central China Cardiovascular Hospital from December 2017 to March 2022. Based on the IVUS results, the coronary plaques were divided into vulnerable and non-vulnerable plaque groups. Finally, 43 patients with a total of 88 coronary artery plaques were included, of which 26 were vulnerable plaques. Plaque analysis were performed on the CCTA images, including qualitative parameters such as low-density plaques (LAP), "napkin-ring" sign (NRS), spotty calcification (SC) and positive remodeling (PR), and the quantitative parameters such as minimum lumen area (MLA), total plaque volume (TPV), lesion length, volume and proportion of calcified plaque and fibrous plaque. The differences of CCTA parameters between the two groups were compared using t-test, chi-square test, and rank sum test. The association between CCTA parameters and the risk of vulnerable plaque was evaluated by logistic regression. Different CCTA parameters were used to establish qualitative, quantitative, and hybrid models, and the diagnostic efficacy of different models for vulnerable plaque was evaluated using the receiver operating characteristic (ROC) curve. Results:There were significant differences in NRS ( χ2=14.22, P<0.001), MLA ( Z=3.25, P=0.001), lesion length ( Z=-3.28, P=0.001), TPV ( Z=-2.04, P=0.041), calcified plaque volume ( Z=-2.52, P=0.012) and fibrous plaque volume ( Z=-2.10, P=0.035) between vulnerable and non-vulnerable plaque groups. The logistic regression analysis showed that NRS ( OR=9.66, 95% CI 2.36-39.54), MLA ( OR=0.76, 95% CI 0.59-0.99) and lesion length ( OR=1.03, 95% CI 1.00-1.07) were independent risk factors for vulnerable plaques. The diagnostic efficacy of the hybrid model based on CCTA parameters was superior to the qualitative model [hybrid model: area under the ROC curve (AUC)=0.82, 95% CI 0.72-0.89; qualitative model: AUC=0.68, 95% CI 0.57-0.78; Z=2.57, P=0.010]. Conclusions:CCTA parameters NRS, MLA, and lesion length are independent risk factors for coronary vulnerable plaques. The diagnostic efficacy of the hybrid model based on CCTA parameters is superior to the qualitative model for vulnerable plaques.