Object To develop a method for the determination of flavonoids from the tender stem and leaf of Ampelosis grossedentata (Hand. Mazz.) W. T. Wang, and for its quality control. Methods Differential spectrophotometry was used at the wavelength of (318?1) nm, while taking dihydromyricetin as index. Results The regression equation, within the range of the control concentration in 4 576～22 88 ?g/mL, was A=29 56 C+0 005 5, with a good linearity (r=0 999 8) between the absorbance and concentration. The average recovery rate was 100 8% and RSD was 1 9% (n=5). Conclusion The method is simple, reliable and easy to operate and suitable for the quality control of Chinese medicinal materials with a better reproducibility.

【Objective】 To retrospectively analyze the clinical use of low-dose blood components in Dongguan and the trend of clinical pediatric blood use, so as to provide reference for better preparation and inventory management of low-dose blood components in blood centers. 【Methods】 The clinical consumption of RBCs, platelets and plasma of Dongguan Blood Center from 2015 to 2020 was counted. The compositions and changes of low-dose blood components by specifications (0.25 U, 0.5 U), years and hospitals (public grade A general hospital, public grade A specialized hospital, private grade A hospital, private hospital equivalent to grade A, regional central hospital, public township hospital, small private hospital) were analyzed. 【Results】 The cumulative growth rates of low-dose RBCs, platelets, and plasma in 6 years were 10.78%, 1 098.55% and -29.41%, respectively, and the compound annual growth rates were 2.07%, 64.34% and -6.73%, respectively. The composition of low-dose blood components in RBCs, platelets and plasma was different (P<0.05) in different levels of hospitals, among which RBCs and plasma were the mostly used in public grade A specialized hospital, accounting for 45.08% (7 272 /16 133) and 53.18% (7 199/13 373) respectively, while platelets were the mostly used in private grade A management hospitals, accounting for 77.38% (3 393/4 385), dominated by apheresis platelets 53.84% (1 144/2 125) and irradiated apheresis platelets 99.51% (2 249/2 260). The composition ratios of 0.25 U and 0.5 U RBCs used in different hospitals were significantly different (P<0.05). The 0.25 U RBCs were used mostly in public grade A hospitals (62.60%, 3 502/5 594) and 0.5 U RBCs in public grade A specialized hospitals (62.09%, 6 544/10 539). 【Conclusion】 The total consumption of low-dose blood components in clinical pediatrics from 2015 to 2020 were as follows: platelets had increased significantly year by year, RBCs had increased steadily and with fluctuation, plasma had a downward trend year by year. The consumption volume and varieties used in different levels of hospitals were uneven, which may be related to the development of pediatrics departments in hospitals and their capabilities to conduct new business. Regular monitoring of the trend of low-dose blood component consumption is of great significance to guarantee the pediatric clinical blood supply.

Objective : To compare the wear of Ceramage and IPS e.max Press offering foundation for nonmetallic materials selection in clinical. Methods : 20 class I cavities were prepared in the approximal flattened sides of the extracted human maxillary first molars. The cavities were divided into 2 groups randomly, and then restored with Ceramage or IPS e.max Press. Inlays were prepared according to the manufactures’ instructions with indirect methods and cemented with Varolink N. The non-wear extracted maxillary third molars were used as antagonistic enamel cusps after standardized prepared. After the self-made wear-testing device concluded 200,000 cycles under a load of 20 N, the wear depth of specimens and antagonistic enamel cusps was assessed by Kavo PREP assistant. Results : The wear in Ceramage group was (298.30 ± 40.02) μm, while the wear of normal enamel was (206.60 ± 49.17) μm. The wear in IPS e.max Press group was (212.90 ± 61.21) μm, while the wear of normal enamel was (217.00 ± 25.10) μm. The wear of IPS e.max Press inlays was higher than Ceramage inlays (P < 0.05). Ceramage inlays showed higher wear than normal enamel (P < 0.05), while IPS e.max Press inlays was not statistically different from the normal enamel (P > 0.05). Conclusions Ceramage has more wear than IPS e.max Press. Ceramage shows higher wear compared with normal enamel, while IPS e.max Press has lower antagonistic war compared with normal enamel.

【Objective】 To investigate the influence of different packaging methods on the volume of low-dose(0.5 U) suspended leucocyte depleted red blood cells(SLD RBC) and provide reference for accurate labeling. 【Methods】 Bags of SLD RBC in 1.5 U and 2 U were randomly sampled to measure the weight and specific gravity of each bag, so as to estimate the blood volume.The relationship between the weight and volume of 0.5 U blood, split from different parent bags, was analyzed and the linear regression equation was put forward.The regression equation was used to calculate and analyze the difference in the volume of 0.5 U SLD RBC prepared by three different packaging methods (A: manual multi-bag average packing; B: instrument multi-bag average packing; C: manual single-bag packing) in actual work. 【Results】 The specific gravity of 1.5 U (38 bags) and 2 U SLD RBC (39 bags) were (1.090±0.011) g/mL and (1.097±0.013) g/mL, respectively, and the difference was statistically significant (P<0.05). After the 0.5 U subsidiary bags were split from the parent bags(1.5 U or 2 U), the regression equations for the volume (Y) of 0.5 U and gross weight (X) of the whole bag were respectively: Y1.5 U packing=0.902 7X-12.52 (P<0.05) and Y2 U packing=0.905 6X-13.15(P<0.05). In actual blood packaging, the average blood volume of 0.5 U subsidiary bags split from 1.5 U bag, using method A and B, were smaller than those split from 2 U bag [(62.12±5.38) mL and (62.50±6.77) mL vs (67.72±3.81) mL and(68.39±6.44)mL] (P<0.05), with the deviation of low-dose blood volume from 5.593 mL to 5.887 mL.The volume deviation by method B (10.84% and 9.42%) were greater than that by method A (8.67% and 5.63%). The average volume of 0.5 U subsidiary bags split from 1.5 U and 2 U by method C were (65.49±1.72) mL and (64.99±1.91) mL (P>0.05), with volume deviation at 2.63% and 2.94%, respectively.The mean volume value of overall 0.5 U blood (n=483) was (65.35±5.34) mL. 【Conclusion】 For packaging 0.5 U subsidiary bags, the instrument multi-bag packaging showed the largest volume deviation, followed by the manual multi-bag packaging and the single-bag packaging.The volume labeling of low-dose SLD RBC should be established, according to the specifications of parent bags and specific gravity.

Objective: To study the difference in the flora structure and gene function of dental plaque in caries-free and caries-active preschool children by 16S rRNA sequencing. Methods: After oral examination of 96 preschool children aged 3-6 years, they were divided into 3 groups according to their decayed, missing and filled surface (dmfs) index: group CF with no caries (n=31), group ECC with moderate early childhood caries (n=29) and group SECC with severe early childhood caries (n=36). Dental plaques were collected, and DNA was extracted and then underwent metagenomic sequencing by Illumina HiSeq 2 500. The bacterial community structure was analyzed by Qiime. Results : A total of 12 phyla, 31 classes, 31 orders, 50 families, 92 genera and 1 104 species were found in the dental plaque samples of the three groups, most of which belonged to 9 dominant genera, including Streptococcus, Veillonella, etc. The microbial diversity of the dental plaques in the three groups was similar (P > 0.05). Veillonella, Lactobacillus, Megasphaera, and Scardovia in the SECC group were significantly higher than those in the other two groups. There was a significant correlation between the decayed, missing and filled surface (dmfs) index and the genus. Bifidobacterium, Veillonella, Lactobacillus had a positive correlation with the dmfs index, while Eikenella had a negative correlation with the dmfs index. Indicator species analysis showed that Atopobium, Veillonella, Megasphaera, Scardovia, Lactobacillus and Bifidobacterium had high indicative values in the SECC group. Conclusion There are significant differences in plaque microbiota among preschool children with different caries sensitivities. Veillonella, Megasphaera, Scardovia, Lactobacillus, Bifidobacterium and Atopobium may be the indicator genera of severe early children caries.