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71.
CHENG Jianwei SHI Yun WANG Youjie YE Linxiang ZHOU Yikai.State Environmental Protection Administration of China 《国外医学:社会医学分册》2006,(4)
提出环境污染健康损害判定工作程序及步骤,给出已知污染物或未知污染物造成健康损害判定工作框图,并提出健康损害判定:①必须经环境保护主管部门进行资质认定的环境污染健康损害判定机构承担;②具有健康损害判定资质的机构应建立相应专家组;③健康损害判定专家组按相关标准根据医学诊断、环境证据及因果关系进行健康损害判定。 相似文献
72.
Precise evaluation for flexural ultimate capacity of bridges which are subjected to the collision of over-height trucks is essential for making decisions on corresponding maintenance, strengthening or replacement. When the span of a cross-line continuous bridge with a double-box girder was hit by an overly high vehicle, the concrete floor of one girder was severely damaged, and part of the prestressed strands and reinforcements in the girder were broken. After the double-box girder was removed and separated into two single box girders, the ultimate flexural capacity of both box girders was studied by destructive tests, and a comparison was made between the damaged and undamaged girders. Moreover, finite element analysis was conducted to simulate the failure process. The results show that the flexural bearing capacity of the damaged box girder decreased by 33%, but it was still 1.07 times greater than the design bearing capacity, which basically meets the design requirements. Also, the damaged box girder showed a desirable serviceable limit state for three-axle vehicles and five-axle vehicles, but showed an undesirable serviceable limit state for six-axle vehicles. This study shows that repairing or strengthening the damaged span may be better than demolishing and rebuilding the whole superstructure bridge. 相似文献
73.
Chuanyou Yi Dandan Li Xiao Guo Jinhui Wang Cenxi Liu Guangxing Lu Yan Sun He Huang Shangyu Hong Jin Li 《Nutrients》2022,14(11)
The diet-induced obesity (DIO) mouse model has been widely used for obesity studies. The effects of storage conditions on the composition of nutrients in high-fat diets (HFDs) and their impact on metabolic homeostasis have not been systemically investigated. In the current study, we tested the effects of HFDs stored under different conditions and found that mice fed a HFD stored in the fridge (HFDfri) gained less weight than those fed HFDs stored in the freezer (HFDfre). Further analysis revealed that changes in the relative abundance of medium-chain triglyceride (MCT) in the HFDfri, which have much lower intestinal absorption rates, contributed to the body weight differences. In contrast, exacerbated liver damage and elevated levels of unfolded protein response (UPR) was observed in the mice fed by HFDfri. Depletion of the UPR-regulated gene Nnmt alleviated liver damage via the inhibition of the integrated stress response (ISR). Our study, for the first time, provides evidence that HFD storage conditions can have a significant impact on both body weight changes and liver damage in the DIO model. 相似文献
74.
Yao Xiao Wenxia Yao Mingzhen Lin Wei Huang Ben Li Bin Peng Qinhai Ma Xinke Zhou Min Liang 《Drug delivery》2022,29(1):1712
This study aimed to explore the anti-tumor effect of icaritin loading poly (lactic-co-glycolic acid) nanoparticles (refer to PLGA@Icaritin NPs) on gastric cancer (GC) cells. Transmission Electron Microscope (TEM), size distribution, zeta potential, drug-loading capability, and other physicochemical characteristics of PLGA@Icaritin NPs were carried out. Furthermore, flow cytometry, confocal laser scanning microscope (CLSM), Cell Counting Kit-8 (CCK-8), Transwell, Elisa assay and Balb/c mice were applied to explore the cellular uptake, anti-proliferation, anti-metastasis, immune response activation effects, and related anti-tumor mechanism of PLGA@Icaritin NPs in vitro and in vivo. PLGA@Icaritin NPs showed spherical shape, with appropriate particle sizes and well drug loading and releasing capacities. Flow cytometry and CLSM results indicated that PLGA@Icaritin could efficiently enter into GC cells. CCK-8 proved that PLGA@Icaritin NPs dramatically suppressed cell growth, induced Lactic dehydrogenase (LDH) leakage, arrested more GC cells at G2 phase, and inhibited the invasion and metastasis of GC cells, compared to free icaritin. In addition, PLGA@Icaritin could help generate dozens of reactive oxygen species (ROS) within GC cells, following by significant mitochondrial membrane potentials (MMPs) loss and excessive production of oxidative-mitochondrial DNA (Ox-mitoDNA). Since that, Ox-mitoDNA further activated the releasing of damage associated molecular pattern molecules (DAMPs), and finally led to immunogenic cell death (ICD). Our in vivo data also elaborated that PLGA@Icaritin exerted a powerful inhibitory effect (∼80%), compared to free icaritin (∼60%). Most importantly, our results demonstrated that PLGA@Icaritin could activate the anti-tumor immunity via recruitment of infiltrating CD4+ cells, CD8+ T cells and increased secretion of cytokine immune factors, including interferon-γ (IFN-γ) tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1).++ Our findings validate that the successful design of PLGA@Icaritin, which can effectively active ICD and facilitate tumor recruitment in GC through inducing mitoDNA oxidative damage. 相似文献
75.
目的通过对齐齐哈尔地区高血压病人治疗情况及血压、心、脑、肾、大血管损害情况的2年的跟踪调查,观察不同的降压药物对患者降压达标率,靶器官损害程度的影响。方法对齐齐哈尔地区确诊为高血压病者523人根据服药情况分为三组:A组、B组和C组。对这三组病人血压情况、靶器官损害情况通过心电图、心脏彩超、血脂、肾功等进行评价,同时还进行了组别之间的经济学评价。结果A组在血压控制达标率,保护靶器官方面均优于B、C组,A、B、C三组在长期服用的药物价格上依次减少,但住院率、恶性事件顺次增加。结论高血压病的药物治疗更强调合理和规范。本研究中A组使用了良好的规范的降压药物从而大大减低了心脑血管恶性事件的发生率,获得了良好的价效比。 相似文献
76.
Background: The present study investigates the relationship between hypertransaminasemia and malnutrition on the basis of a very large number of patients. We assume that the level of transaminases not only reflects the extent of underlying liver cell damage but also provides information about the metabolic situation under conditions of energy deficiency. Methods: We present an observational study in two different samples. The first sample consists of 3755 patients (mean age 22.7 years, Range 12–73 years; mean BMI 15.4 kg/m2, range 8.1–25.7) out of a total of 4212 patients with anorexia nervosa treated in the Roseneck Clinic within five years for whom a complete admission laboratory was available. The second sample was obtained from a special ward for medically at-risk patients with eating disorders. During the period in question, four hundred and ten patients with anorexia nervosa were treated. One hundred and forty-two female patients (mean age 26.4 years, Range 18–63 years; mean BMI 11.5 kg/m2, range 8.4–13) had a BMI of thirteen or less and a complete data set was obtained at admission and weekly in the following four weeks after admission. Results: The increase in liver transaminases shows a very high correlation with weight in sample one (N = 3755). The analysis of variance shows highly significant (<0.001) correlations with an F-value of 55 for GOT/AST and 63 for GPT/ALT. Nevertheless, the variance within the groups with the same BMI is quite high. With re-nutrition in sample two, GOT/AST decreased on average from 71 U/L to 26 U/L (MANOVA F 10.7, p < 0.001) and GPT/ALT from 88 to 41 U/L (F = 9.9, p < 0.001) within four weeks. Discussion: Below a BMI of about 13, the nutritional status of the patients becomes so critical that the energy supply of the patient is increasingly dependent on the autophagy of the liver, which can be seen in the very strong increase in transaminases here. Refeeding leads very quickly to the normalisation of the transaminases and, thus, a stabilisation of the metabolism leading also to a decrease in autophagy. 相似文献
77.
大豆异黄酮对慢性肾损害大鼠肾功能及脂代谢的影响 总被引:1,自引:0,他引:1
目的观察不同剂量大豆异黄酮(SIF)对慢性肾损害大鼠肾功能及脂质代谢的影响。方法采用腺嘌呤灌喂方法建立肾损害大鼠模型,按体质量大小编号随机分为3组,每组9只。分别为肘照组,予同等量花生油灌喂;SIF小剂量组,予SIF6mg/(kg·d);大剂量组,予SIF12mg/(kg·d)。观察第0天、第21天、第42天血浆甘油三酯、总胆固醇、高密度脂蛋白、低密度脂蛋白、血浆尿素、血清肌酐水平以及尿蛋白排泄量。结果SIF治疗组血浆尿素、血清肌酐水平下降及尿蛋白排泄量减少,血浆甘油三酯、总胆固醇、低密度脂蛋白下降,高密度脂蛋白水平升高,上述各项指标与对照组相比,差异均有统计学意义(P〈0.05),SIF不同剂量组之间比较差异无统计学意义(P〉0.05)。结论低剂量SIF就可起到改善肾损害大鼠的脂代谢紊乱,减少尿蛋白排泄和稳定肾功能的作用。 相似文献
78.
ObjectiveTo evaluate the feasibility and surgical outcome of the modified method of cervical conization with hybrid use of a cold knife and an electric knife.MethodsA retrospective analysis of cervical conization for high-grade squamous intraepithelial lesions was performed between January 2020 and December 2020. Traditional cold knife conization and modified conization were used. The clinical characteristics and surgical outcomes were compared between these methods.ResultsNinety-two patients with high-grade squamous intraepithelial lesions were included. Traditional conization was performed in 46 patients, and the modified method was used in 46 patients. There were no differences in clinical characteristics, such as age, menopausal status, and conization height, between the methods. Intraoperative blood loss with the modified method was significantly lower than that with traditional conization (27.6 ± 4.7 vs 51.3 ± 18.3 mL). Postoperative vaginal bleeding requiring emergent measures, such as prolonged gauze compression, sutures, or electrocautery, was significantly less with the modified method than with traditional conization (4.3% vs 17.4%). A median follow-up of 10.2 months showed no significant difference in persistence or recurrence between the methods.ConclusionsThe modified method of cervical conization with hybrid use of cold and electric knives may be a good alternative to traditional cold knife conization. 相似文献
79.
A novel damage model for concrete has been developed, which can reflect the complex hysteresis phenomena of concrete under cyclic loading, as well as other nonlinear behaviors such as stress softening, stiffness degradation, and irreversible deformation. The model cleverly transforms the complex multiaxial stress state into a uniaxial state by equivalent strain, with few computational parameters and simple mathematical expression. The uniaxial tensile and compressive stress–strain curves matching the actual characteristics are used to accommodate the high asymmetry of concrete in tension and compression, respectively. Meanwhile, an unloading path and a reloading path that can reflect the hysteresis effect under cyclic loading of concrete are established, in which the adopted expressions for the loading and unloading characteristic points do not depend on the shape of the curve. The proposed model has a concise form that can be easily implemented and also shows strong generality and flexibility. Finally, the reliability and correctness of the model are verified by comparing the numerical results with the three-point bending beam test, cyclic loading test, and a seismic damage simulation of the Koyna gravity dam. 相似文献
80.