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171.
Jiang  Chang-qing  Ma  Ling-ling  Lv  Zhen-dong  Feng  Fan  Chen  Zhi  Liu  Zu-De 《Journal of natural medicines》2020,74(3):533-544
Journal of Natural Medicines - Polydatin, a natural product, is detected in many daily diets, such as grape juices and peanut. Autophagy regulation is recognized as a new potential strategy for...  相似文献   
172.
The effect of temperature on the toxicities of four diamide insecticides (chlorantraniliprole, cyantraniliprole, flubendiamide, tetraniliprole) against three lepidopteran insects (Helicoverpa armigera, Plutella xylostella, Athetis lepigone) were determined from 15 to 35 °C by exposing third-instar larvae to dip-treated cabbage leaf. The results indicated that increase in temperature led to an increase significantly and regularly in the toxicities of the four diamide insecticides against P. xylostella and H. armigera, but not for A. lepigone. The temperature coefficients (TCs) of the four diamide insecticides increased from 15 to 35 °C. Tetraniliprole for H. armigera (+825.83), chlorantraniliprole for P. xylostella (+315.65) and cyantraniliprole for H. armigera (+225.77) exhibited high positive TCs. For A. lepigone, temperature had a positively weak or no effect on the toxicities of most of the diamide insecticides from 20 to 30 °C, but a higher effect from 30 to 35 °C. In addition, the toxicities of chlorantraniliprole, cyantraniliprole and tetraniliprole all decreased from 15 to 20 °C. This study can guide pest managers in choosing suitable ambient field temperature when spraying diamide insecticides against lepidopteran insects.  相似文献   
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Knowledge of subinguinal microsurgical varicocelectomy is of fundamental importance to ensure that varicocele is resolved and testicular function is preserved. Our study aimed to describe the number of veins, arteries and lymphatics in the subinguinal spermatic cord and to clarify their differences between two sides, between patients with different complaints and between varicoceles with different clinical grades. A total of 102 consecutive patients underwent 162 primary subinguinal microsurgical varicocelectomies, during which the number of vessels with different diameters was recorded. A mean number of 12.9 internal spermatic veins, 0.9 external spermatic veins, 1.8 internal spermatic arteries and 2.9 lymphatics were identified per cord. 88.2% of the internal spermatic arteries were surrounded by a dense complex of adherent veins. The external spermatic vein or veins were found in 49.4% of the cases. The mean number of medium (1–3 mm in diameter) internal spermatic veins on the left was larger than that on the right (< 0.001). The mean number of medium internal spermatic veins in grade III varicocele was larger than that in grade I or grade II (< 0.015). There was no significant anatomical difference between the men presenting for infertility, chronic testicular pain and both the two complaints.  相似文献   
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This study investigated whether bone marrow mesenchymal stem cell(BMSC) transplantation protected ischemic cerebral injury by stimulating endogenous erythropoietin. The model of ischemic stroke was established in rats through transient middle cerebral artery occlusion. Twenty-four hours later, 1 × 106 human BMSCs(h BMSCs) were injected into the tail vein. Fourteen days later, we found that h BMSCs promoted the release of endogenous erythropoietin in the ischemic region of rats. Simultaneously, 3 μg/d soluble erythropoietin receptor(s EPOR) was injected into the lateral ventricle, and on the next 13 consecutive days. s EPOR blocked the release of endogenous erythropoietin. The neurogenesis in the subventricular zone was less in the h BMSCs + s EPOR group than in the h BMSCs + heat-denatured s EPOR group. The adhesive-removal test result and the modified Neurological Severity Scores(m NSS) were lower in the h BMSCs + s EPOR group than in the heat-denatured s EPOR group. The adhesive-removal test result and m NSS were similar between the h BMSCs + heat-denatured s EPOR group and the h BMSCs + s EPOR group. These findings confirm that BMSCs contribute to neurogenesis and improve neurological function by promoting the release of endogenous erythropoietin following ischemic stroke.  相似文献   
179.
Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood stem cells. After 30 days, the maximum load, maximum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neurotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These findings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, improve biomechanical properties, and contribute to the recovery after injury.  相似文献   
180.
碘-125粒子植入治疗肝细胞癌的剂量学   总被引:1,自引:0,他引:1  
放射性粒子植入为肝癌的治疗提供了一条新的有效的途径,尤其是碘-125粒子的应用,在世界范围内引起了越来越多的学者的兴趣;然而其剂量学上却没有一个统一的标准.为提高碘-125粒子治疗肝癌的疗效、保护肿瘤周围正常组织器官,有必要对碘-125粒子植入治疗肝细胞癌的剂量学进行前瞻性研究,寻找其最佳处方剂量和粒子的最佳活度.  相似文献   
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