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61.
《Planning》2019,(5)
目的探讨Ranson评分对高脂血症性急性胰腺炎(hyperlipidemic acute pancreatitis,HLAP)分型的早期预测价值。方法回顾性收集2014年1月至2018年10月在北京协和医院急诊科就诊的中重度HLAP患者资料,包括年龄、性别、血脂水平、血糖、白细胞、乳酸脱氢酶(lactate dehydrogenase, LDH)、谷草转氨酶(aspartate aminotransferase,AST)以及入院48 h后的血细胞比容、尿素氮、血钙、碱缺乏、液体丢失量。按照疾病严重程度分为中度和重度HLAP,并计算每例患者的Ranson评分。采用t检验比较中度和重度HLAP组间Ranson评分的差异,运用受试者工作特征(receiver operating characteristic,ROC)曲线分析得出最佳界值,计算其敏感度和特异度,以卡方检验验证其一致性。结果共计99例符合入选和排除标准的HLAP患者进入本研究,其中中、重度HLAP分别为45例和54例。重度HLAP组的Ranson评分显著高于中度组,差异具有统计学意义(5. 19±1. 33比3. 09±1. 35,P<0. 01)。ROC曲线分析显示4为最佳临界值,敏感度为75. 9%,特异度为84. 4%;以4为临界值,Ranson评分3~4者符合中度HLAP的表现,Ranson评分>4符合重度HLAP表现,中度和重度组的Ranson评分与疾病分型一致(P<0. 01)。结论 Ranson评分可用于中度和重度HLAP分型早期预测,3~4分提示中度HLAP,>4分提示重度HLAP。  相似文献   
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To determine the compositions of Forsythia suspensa leaves tea (FSLT) and its safety, the chemical compounds were analysed with some methods, and the toxicity was evaluated in Kunming mice and Wistar rats. The results showed that FSLT contained rich flavonoid, lignans, triperpene acids, amino acids, and mineral elements. In the acute toxicity study, none of the mice died, and no obvious poisoning symptoms were observed after 14 days in mice at the dose of 15 mg/g·body weight (bw) FSLT; in the sub-chronic toxicity, no abnormal or dead rat was found at the dose of 1, 3, and 10 mg/g·bw during 90 days feeding administration; there was no significant difference in bw and food consumption; no significant differences were found in each hematology and serum biochemistry parameter and organ/body weight ratio comparing with the control experimental group. The results revealed that the FSLT has low or no toxicity via oral administration. Therefore, FSLT is very suitable and safe to be used as a new resource food.  相似文献   
64.
The aim of this study was to assess the value of serum iron concentration in the diagnosis of acute inflammation in cattle. The diagnostic value of this approach was compared with that of various other hematological tests, including commonly used techniques that measure the levels of various other acute-phase proteins. The study population comprised 10 cows with acute traumatic reticuloperitonitis (RPT group) and 10 cows with acute mastitis (mastitis group) admitted to the Veterinary Teaching Hospital at Firat University (Elazi?, Turkey). Ten cows from local barns, kept and fed under same conditions as the diseased animals, were used as controls. After the clinical examination, blood samples were collected for biochemical, hematological, and acute-phase protein (haptoglobin, serum amyloid A, α-1 acid glycoprotein, and fibrinogen) analyses. The mean levels of serum iron in the RPT, mastitis, and control groups were 6.00, 7.82, and 26.78 µmol/L, respectively. Serum iron level was significantly reduced in the RPT and mastitis groups. The results of this study indicate that serum iron analysis, preferably in combination with other markers of inflammation, may be a useful diagnostic tool for acute inflammation in cattle. Because serum iron measurement is individually available and easily applicable, it may be used for clinical cases as well as the determination of herd health.  相似文献   
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66.
Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs) is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH) and luteinizing hormone (LH), and lowered etradiol (E2) serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T) diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions.  相似文献   
67.
马庆岩  张亨 《氯碱工业》2012,48(10):36-39
介绍了三氯乙醛的发展历史、物化性质、毒性、危害及应用,综述了三氯乙醛近30年来分析检测研究进展情况.  相似文献   
68.
Five-day exposure of clary sage (Salvia sclarea L.) to 100 μM cadmium (Cd) in hydroponics was sufficient to increase Cd concentrations significantly in roots and aboveground parts and affect negatively whole plant levels of calcium (Ca) and magnesium (Mg), since Cd competes for Ca channels, while reduced Mg concentrations are associated with increased Cd tolerance. Total zinc (Zn), copper (Cu), and iron (Fe) uptake increased but their translocation to the aboveground parts decreased. Despite the substantial levels of Cd in leaves, without any observed defects on chloroplast ultrastructure, an enhanced photosystem II (PSII) efficiency was observed, with a higher fraction of absorbed light energy to be directed to photochemistry (ΦPSΙΙ). The concomitant increase in the photoprotective mechanism of non-photochemical quenching of photosynthesis (NPQ) resulted in an important decrease in the dissipated non-regulated energy (ΦNO), modifying the homeostasis of reactive oxygen species (ROS), through a decreased singlet oxygen (1O2) formation. A basal ROS level was detected in control plant leaves for optimal growth, while a low increased level of ROS under 5 days Cd exposure seemed to be beneficial for triggering defense responses, and a high level of ROS out of the boundaries (8 days Cd exposure), was harmful to plants. Thus, when clary sage was exposed to Cd for a short period, tolerance mechanisms were triggered. However, exposure to a combination of Cd and high light or to Cd alone (8 days) resulted in an inhibition of PSII functionality, indicating Cd toxicity. Thus, the rapid activation of PSII functionality at short time exposure and the inhibition at longer duration suggests a hormetic response and describes these effects in terms of “adaptive response” and “toxicity”, respectively.  相似文献   
69.
Acute toxicity in Wistar rat and the impact of hydrolysed collagen (HC) from seabass skin on in vitro cell proliferation and collagen production were studied using L929 fibroblasts. HC was rich in glycine (326 residue/1000 residue) and imino acids (196 residue/1000 residue). MALDI mass spectrum of HC showed several low MW peptides with MW range of 1050–1330 Da as the major components. Based on acute oral cytotoxicity test in Wistar rat, HC was considered as safe with LD50 value higher than 5000 mg kg?1 body. HC could promote L929 cell growth, especially when used in combination with vitamin C (VitC) at a ratio of 2:1. HC/VitC (2:1) mixture also exhibited the higher enhancement effect on collagen production of L929 cells, compared with HC or VitC alone. Thus, HC could be a promising candidate for biological applications, especially in combination with VitC, as nutraceuticals for skin care.  相似文献   
70.
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