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91.
Thuong PT Lee CH Dao TT Nguyen PH Kim WG Lee SJ Oh WK 《Journal of natural products》2008,71(10):1775-1778
Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active. 相似文献
92.
Huang KL Chen CS Hsu CW Li MH Chang H Tsai SH Chu SJ 《The American journal of Chinese medicine》2008,36(2):301-311
Baicalin is a flavonoid present in many traditional Chinese medicines. A number of studies show that baicalin has anti-inflammatory actions and protects against a variety of tissue and organ injuries. The effect of baicalin in lipopolysaccharide (LPS)-induced acute lung injury is not well studied. In this study, typically acute lung injury was induced in rat by intratracheal injection of LPS, which increased lactate dehydrogenase activity and protein content in bronchoalveolar lavage fluid, wet/dry lung weight ratio, Evan's blue dye leakage, and neutrophil infiltration. Baicalin (20 mg/kg) was administrated 1 hour before or 30 min after LPS injection. Both pre and post-treatment with baicalin attenuated the increase of these parameters and improved histological finding. Our results suggest that baicalin has a therapeutic effect on LPS-induced acute lung injury. 相似文献
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96.
Hung JH Fu CY Chen CY Chao KC Hung J 《The journal of obstetrics and gynaecology research》2008,34(4):518-523
Objective: The purpose of the present study was to build a database of reference ranges of fetal nasal bone length (NBL) in a Chinese population. The accuracy rate of detecting Down syndrome was also analyzed using fetal NBL as a marker.
Methods: The control group of fetuses included 342 normal singleton pregnancies with no chromosomal or congenital anomalies. The present study was a cross-section study and the control group was used to construct percentile values of NBL from 13 to 29 gestational weeks of age. Two-dimensional ultrasonography was used for the nasal bone studies. Measurements of NBL were collected and each fetus contributed a single value to the reference sample. During the study period, 14 fetuses with Down syndrome were examined. Measurement of fetal NBL was made during amniocentesis, with gestational age ranging from 13 to 19 weeks.
Results: From 342 normal fetuses with gestational age ranging from 13 to 29 weeks, reference ranges of NBL were constructed. The reference ranges were constructed from the 100(1 − p)% reference range: , where Ŷ = 25 − exp(3.58 − 0.044 × t + 0.0006 × t2 ), with Ŷ being the fitted mean of regression model and t being gestational age (weeks). Using fetal NBL, the regression model was Pr (Down syndrome) = exp( W )/[1 + exp( W )], where W = 0.62–4.80 × NBL (multiples of the median) in predicting Down syndrome. Fetal NBL was found to have a sensitivity and specificity of 0.78 and 0.78, respectively, in predicting Down syndrome in the second trimester of pregnancy.
Conclusions: Fetal NBL measurement can provide a simple and useful algorithm to predict Down syndrome during the second trimester of pregnancy. 相似文献
Methods: The control group of fetuses included 342 normal singleton pregnancies with no chromosomal or congenital anomalies. The present study was a cross-section study and the control group was used to construct percentile values of NBL from 13 to 29 gestational weeks of age. Two-dimensional ultrasonography was used for the nasal bone studies. Measurements of NBL were collected and each fetus contributed a single value to the reference sample. During the study period, 14 fetuses with Down syndrome were examined. Measurement of fetal NBL was made during amniocentesis, with gestational age ranging from 13 to 19 weeks.
Results: From 342 normal fetuses with gestational age ranging from 13 to 29 weeks, reference ranges of NBL were constructed. The reference ranges were constructed from the 100(1 − p)% reference range: , where Ŷ = 25 − exp(3.58 − 0.044 × t + 0.0006 × t
Conclusions: Fetal NBL measurement can provide a simple and useful algorithm to predict Down syndrome during the second trimester of pregnancy. 相似文献
97.
Group B streptococcus infection in pregnancy 总被引:1,自引:0,他引:1
Winn HN 《Clinics in perinatology》2007,34(3):387-392
Group B streptococcus (streptococcus agalactiae), a gram-positive coccus, is one of the major causes of maternal or neonatal severe infection and sepsis. Maternal infection associated with GBS includes acute chorioamnionitis, endometritis, and urinary tract infection. 相似文献
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Shih-Te Hung Jelmer Cnossen Daniel Fan Marijn Siemons Daphne Jurriens Kristin Grußmayer Oleg Soloviev Lukas C. Kapitein Carlas S. Smith 《Biomedical optics express》2022,13(6):3275
High-NA light sheet illumination can improve the resolution of single-molecule localization microscopy (SMLM) by reducing the background fluorescence. These approaches currently require custom-made sample holders or additional specialized objectives, which makes the sample mounting or the optical system complex and therefore reduces the usability of these approaches. Here, we developed a single-objective lens-inclined light sheet microscope (SOLEIL) that is capable of 2D and 3D SMLM in thick samples. SOLEIL combines oblique illumination with point spread function PSF engineering to enable dSTORM imaging in a wide variety of samples. SOLEIL is compatible with standard sample holders and off-the-shelve optics and standard high NA objectives. To accomplish optimal optical sectioning we show that there is an ideal oblique angle and sheet thickness. Furthermore, to show what optical sectioning delivers for SMLM we benchmark SOLEIL against widefield and HILO microscopy with several biological samples. SOLEIL delivers in 15 μm thick Caco2-BBE cells a 374% higher intensity to background ratio and a 54% improvement in the estimated CRLB compared to widefield illumination, and a 184% higher intensity to background ratio and a 20% improvement in the estimated CRLB compared to HILO illumination. 相似文献