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Endoscopic ultrasound (EUS) has been greatly developed in the diagnosis of digestive diseases. In recent years, with the continuous innovation of endoscopic technology and accessories, important breakthroughs have been made in endoscopic ultrasound-guided interventional therapy, especially in the treatment of refractory biliary and pancreatic diseases. Based on the latest literatures and work experience, in this paper, we reviewed the latest progress of EUS interventional treatment for biliary and pancreatic diseases, including EUS- guided bile duct drainage, EUS-guided gallbladder drainage, EUS-guided pancreatic duct drainage, EUS guided-pancreatic pseudocyst drainage, and EUS guided pancreatic tumor treatment.

The growth cycle of tellurium zinc cadmium crystals is long and the growth system is complex. When using vertical Bridgman or vertical gradient freezing methods to grow tellurium zinc cadmium (CdZnTe) crystal materials, the growth process is often difficult to observe intuitively, and there is no corresponding means to detect the temperature field inside the crystals, which brings inconvenience to improve the crystal growth process. In this paper, numerical simulation software is used to analyze the influences of furnace air convection on the temperature field of CdZnTe crystal growth. By opening holes at the top and bottom of furnace, gas exchanging occurs between the inside and outside of the furnace, thereby regulates the convection behaviors. Before opening holes, the convection rate is slow (only 10-5 m/s), forming stable convection cells; after opening holes, the convection rate significantly increases (0.25 - 0.90 m/s), and the convection state changes to laminar flow. Through controlling the aperture size (20 - 40 mm) in the model, the laminar flow rate can be effectively regulated. At the same temperature setting, when the flow rate increases from 0.25 m/s to 0.90 m/s, the temperature gradient will increase from 0.5 K/mm to 1.1 K/mm. Furthermore, experimental work is applied on real furnace, the change of temperature filed before and after opening holes were studied. The experimental results of temperature gradient is accord with the simulating results. It is also found that under laminar flow state, increasing convection rate may improve the stability of temperature field. The increase of temperature gradient and the improvement of stability in the temperature field will be beneficial for the preparation of high-quality CdZnTe crystals. [ABSTRACT FROM AUTHOR]

Soil surface microrelief plays an important role on the soil erosion processes like runoff, infiltration, soil sealing and sediment transport. However, there is relatively little study on the soil surface microrelief in soil erosion process and those studies are mostly conducted in the Loess Plateau in China. The purpose of this study was to study the feasibility of applying the Instantaneous-Profile Laser Scanner imported from the USA to determine the features and law of soil surface microrelief evolution in red soil region of Southern China. In this study, three soils derived from Quaternary red clay and Shale widely distributed in red soil region were selected, and the changes of soil surface microrelief during rainfall were studied in three intermittent rainfall events by using the Instantaneous-Profile Laser Scanner. With both its positional accuracy and elevational accuracy amounting to 0.5 mm, the Instantaneous-Profile Laser Scanner has been widely applied to the soil erosion process, soil physical property, statistical analysis of geography and topography etc. In the study, soil surface roughness obtained from the scanned image illustrated the changing process caused by the rainfall and runoff. The results showed that: 1) With the intermittent rainfall continuing, the soil surface roughness decreased, resulting from the combined effect of the detachment of raindrop and the transport of runoff; After the third rainfall event, the surface roughness of soil derived from Shale, soil 1 derived from Quaternary red clay, and soil 2 derived from Quaternary red clay decreased 18.2%, 18.4% and 11.8% respectively; and 2) For all three soils, the greatest decrease of soil surface roughness was found in the first rainfall event, which differed from the other two rainfall events significantly. Specifically, the decreases of the surface roughness of soil derived from Shale (16.1%) and soil 1 derived from Quaternary red clay (19.7%) were much higher than that of soil 2 derived from Quaternary red clay (9.6%) for a higher aggregate water stability compared with the other two soils. For all three soils, in the first rainfall event, most aggregates were broken and soil crust began to form because of rainfall splash leading a sharp decrease of soil surface roughness. In the second and third rainfall event, the decreases of soil surface roughness event were not obvious for soil derived from Shale and soil 2 derived from Quaternary red clay. The crust formed on the soil 1 derived from Quaternary red clay during the third rainfall was prone to be destroyed due to its own unstable soil structure, leading to the increase of its roughness of soil surface. The application of submillimeter-level high-precision laser scanning and computer digital image processing method is in favor of researching quantitatively the characteristics and laws of soil surface microrelief changes during the process of water erosion on hillslope. Meanwhile, this paper throws a light on the study of the soil surface microrelief by discussing its status quo, directions and significance during the water erosion on hillslope. [ABSTRACT FROM AUTHOR]

Objective: To explore the status of supervision of off-label drug use at home and abroad. Methods: Through consultation of literature, a description and analysis were made in the supervision of off-label drug use at home and abroad and related disputes. Results: An outline on the supervision of off-label drug use at home and abroad was summarized from the perspectives of legislation and administrative procedures. Then, a detailed discussion was made on such disputed problems as rationality, adverse reaction monitoring, the right of prescription, insurance issues, mode of hospital supervision, etc. Conclusion: When comparisons were made with those of foreign countries, national laws and administrative regulations concerning off-label drug use are not established yet. In addition, further exploration should be made with an effort to intensify the supervision of off-label drug use, to restrict the right of prescription, and to strengthen internal monitoring of the hospital. [ABSTRACT FROM AUTHOR]

Objective: To train a deep convolutional neural networks (CNN) using a labeled data set to classify the metaphase chromosomes and test its accuracy for chromosomal identification., Methods: Three thousand and three hundred individuals undergoing surveillance for chromosomal disorders at the Laboratory for Comprehensive Prevention and Treatment of Birth Defects, Ningbo Maternal and Child Health Care Hospital from January 2013 to July 2019 were enrolled. A total of 3 300×46 chromosome images were included, of which 70% were used as the training set and 30% were used as the test set for the deep CNN. The accuracy of chromosome counting and "cutting + recognition + arrangement + automatic analysis" of the model were respectively evaluated. Another 80 images were collected to record the time and accuracy of chromosome classification by geneticists and the model, respectively, so as to assess the practical value of the model., Results: The CNN model was used to count the chromosomes with an accuracy of 61.81%, and the "cutting + recognition + arrangement + automatic analysis" accuracy of the model was 96.16%. Compared with manual operation, the classification time of the CNN model has been greatly reduced, and its karyotyping accuracy was only 3.58% lower than that of geneticists., Conclusion: The CNN model has a high performance for chromosome classification and can significantly reduce the work load involved with the segmentation and classification and improve the efficiency of chromosomal karyotyping, thereby has a broad application prospect.

Objective: To assess the value of non-invasive prenatal testing (NIPT) for the identification of fetal chromosomal aneuploidies., Methods: For 9470 pregnant women with a moderate-to-high risk by conventional serological screening or advanced maternal age, peripheral venous blood samples were collected and, following extraction of free fetal DNA, subjected to large-scale parallel sequencing on a Illumina Hiseq2000 platform. Those with a high risk by NIPT were validated by invasive prenatal diagnosis., Results: Out of the 9470 samples, 194 cases (2.0%) were positive by NIPT testing. These included 50 trisomy 21, 11 trisomy 18, 17 trisomy 13, 44 other autosomal aneuploidies, 55 sex chromosomal aneuploidies, and 17 chromosomal copy number variations. As validated by amniotic fluid or umbilical blood chromosomal karyotyping analysis, NIPT has a false positive rate of 2.0%, 18.2%, 41.2%, 97.7%, 81.8%, 94.1%, respectively. The test has a sensitivity of 100% and a specificity of 98.79%., Conclusion: For common chromosomal aneuploidies such as trisomy 21 and trisomy 18, NIPT has a good sensitivity and specificity, therefore has good value for clinical application.

Objective: To assess the value of combined chromosomal karyotyping and BACs-on-Beads(BoBs) assay for the prenatal diagnosis of high risk gravida from Ningbo., Methods: For 2779 women, results of conventional karyotyping analysis and BoBs assay were compared., Results: For common aneuploidies involving chromosomes 13, 18, 21, X and Y, the two methods have yielded a concordance rate of 98.78%. Eight cases detected with microduplication by BoBs were missed by karyotyping analysis. On the other hand, 17 structural chromosomal abnormalities, 10 chimeras and 1 triploidy detected by karyotyping analysis were missed by BoBs., Conclusion: The BoBs technology has featured high throughput and rapidity, and can detect 9 microdeletion syndromes, which can improve the quality of prenatal diagnosis and provide an ideal complementary for conventional chromosomal karyotyping.

Objective: To investigate the correlation between CT image presentations and biochemical indexes in adrenal adenomas and pheochromocytomas., Methods: We retrospectively analyzed the CT features, cortisol rhythm, supine and orthostatic hypertension and 24-h urine methoxy in 209 patients with benign adrenal tumors. The relationship between CT findings and the biochemical indexes were analyzed in patients with different benign adrenal tumors., Results: The 209 cases analyzed included 53 cases of cortisol adenoma, 65 cases of aldosterone adenoma, 45 cases of non-functional adenoma and 46 cases of pheochromocytomas. The plain CT scan values of the 4 groups were 17.25 ± 1.81, 14.52 ± 1.57, 12.20 ± 2.05, 42.42 ± 0.97 HU, enhanced CT values (arterial phase) were 47.82 ± 3.07, 39.23 ± 2.37, 45.35 ± 6.46, and 104.93 ± 5.84 HU, respectively, and the differences between CT scan and enhanced CT values were 30.58 ± 2.29, 24.71 ± 1.55, 33.15 ± 5.18, and 62.51 ± 5.73 HU, respectively. In cortisol adenoma group, cortisol levels measured at 16:00 and 24:00 were positively correlated with plain CT scan value (r=0.506, P=0.0001; r=0.504, P=0.0001) and enhanced CT value (r=0.514, P=0.0001; r=0.554, P=0.0001). In pheochromocytoma group, plain scan CT value and the difference between plain and enhanced CT scan value were correlated with 24-h urine methoxy adrenaline (Rho;=0.342, 0.350; P=0.020, 0.017, respectively) and norepinephrine (Rho;=0.419, 0.412; P=0.004, 0.004, respectively)., Conclusion: Plain and enhanced CT scan values and their combination have important value in differential diagnosis of adenoma and pheochromocytoma tumor, CT values combine with biochemical indexes can reduce misdiagnosis and missed diagnosis of pheochromocytoma.