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51.
粪便类固醇激素检测准确性的影响因素 总被引:1,自引:0,他引:1
近年来,采用非损伤性取样方法监测野生动物的生理状况越来越受到重视。本文对检测过程中影响动物粪便类固醇激素检测准确性的因素进行了分析总结,包括样品的新鲜程度、样品量和保存方法;激素代谢的日节律和季节性变化;动物的年龄、性别和繁殖状态等,以期为粪便类固醇激素检测技术在野生动物中的准确应用提供借鉴。 相似文献
52.
大豆属Soja亚属种皮微形态特征的研究 总被引:1,自引:0,他引:1
采用扫描电镜对大豆属Soja亚属植物的种皮微形态特征进行了系统研究。结果表明,该亚属植物种皮微形态特征在种的水平上具有一定的分类学意义。 相似文献
53.
A SXRF method for determining the relative concentration of trace elements in plasma protein affected by cisplatin 总被引:2,自引:0,他引:2
This article presents an analytical method for the determination of the relative concentrations of trace elements in plasma
protein by gel chromatography combined with SXRF (synchrotron radiation X-ray fluorescence). The fraction of plasma protein
of male Kunming mice (body weight 24.2±0.3 g), treated with a cisplatin ip injection at a dose of 10 mg/kg, was obtained by
the separation of a Sephadex G-50 column (buffered with ammonium acetate, pH 5.7). The SXRF experiments were performed at
the Beijing Electron Positron Collider synchrotron radiation facility. The elements (Pt, S, Ca, Fe, Ni, Cu, Zn, Se, Br, and
Sr) in the fraction of the plasma proteins (>22 kDa) were assayed using highly sensitive SXRF. The relative concentrations
of elements were calculated by a normalization of Compton scattering intensity around 22 keV, after the normalization for
the collection time of the X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate
film for the supporting sample. The determination could prove that the element Pt in plasma was bound with macromolecular
protein. Cu and S were present in the fraction of the protein in mice treated with cisplatin increase, and their ratios of
treated/control were 1.66±0.06 and 1.78±0.33, respectively; Zn decreased to a ratio of 0.78±0.09. Our results are in agreement
with others that cisplatin exposure leads to a marked loss of kidney copper and a moderate rise in kidney zinc. However, this
article primarily describes one of the analytical methods used; it does not emphasize the results of the effect of cisplatin
on trace elements in plasma protein. 相似文献
54.
Qian Cheng Zhiyuan Chen Qing Zhang Senqiang Zhu Rui Liu Hongjun Zhu 《Luminescence》2022,37(2):247-254
Three A–π–A or D–π–D perylene diimide ( PDI ) derivatives with varied groups on π-conjugate were synthesized and characterized. The photophysical properties of these compounds were systematically studied by spectral experiments and density functional theory calculations. All compounds displayed intense absorption bands at 300–800 nm wavelengths. However, diverse groups on the π-conjugate influenced the UV–vis absorption. Electron-withdrawing groups on PDI-2 caused a slight red shift at the 350–400 nm wavelength and a blue shift after 400 nm wavelength. At the same time, the electron-donating substituents on PDI-3 caused an obvious red shift of this band. These PDI derivatives exhibited emission in solution at room temperature (λem = 500–850 nm). The quantum yield of PDI-3 decreased, while the electron-donating substituents were introduced to the π-conjugated motifs. However, the quantum yield of PDI-2 increased when electron-withdrawing substituents were introduced to the π-conjugated motifs. In addition, PDI-1 and PDI-2 exhibited broad triplet transient absorption in the visible region. These photophysical properties could help us to understand the relationship between structure and photophysical properties of perylene diimide derivatives and exploit more original perylene diimide-based optical functional materials. 相似文献
55.
观察发酵乳对脓毒症患者肠黏膜屏障功能及炎症指标的影响。
选取60例确诊为脓毒症的患者, 随机分成对照组和发酵乳组, 每组各30例。对照组给予抗生素及营养支持治疗, 治疗组在常规综合治疗的基础上给予口服发酵乳治疗。在治疗前及治疗1周后分别检测并比较两组患者肠黏膜屏障功能、C-反应蛋白(CRP)、降钙素原(PCT)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平变化, 记录患者APACHEⅡ评分。采用SPSS 22.0软件进行数据统计。
治疗前两组患者的肠屏障功能、PCT和IL-6水平差异无统计学意义(
脓毒症患者在常规综合治疗基础上加用发酵乳可改善肠粘膜屏障功能, 减轻患者全身炎症反应。
56.
57.
研究了热处理肿瘤细胞抗原负载骨髓来源的树突细胞(dendritic cell,DC)对结肠癌小鼠的治疗作用.将小鼠结肠癌细胞CT26热处理后超声破膜,以其细胞裂解液负载BALB/c小鼠骨髓来源的DC,观察DC诱导肿瘤特异性细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)杀伤活性;并将DC接种于荷瘤小鼠皮下,观察其对肿瘤生长的抑制作用及对荷瘤小鼠生存期的影响.发现致敏DC诱导的CTL对CT26肿瘤细胞具有显著的杀伤作用.用致敏DC免疫小鼠后,对小鼠肿瘤的生长具有显著的抑制作用,并能显著延长荷瘤小鼠的生存时间.热处理肿瘤细胞抗原负载的树突细胞对结肠癌小鼠具有显著的治疗效果. 相似文献
58.
59.
Liu Q He X Liu Y Du B Wang X Zhang W Jia P Dong J Ma J Wang X Li S Zhang H 《Biochemical and biophysical research communications》2008,377(3):775-779
Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in X-ray-induced cell death. Under X-ray irradiation, the upregulation of the expression of NADPH oxidase membrane subunit gp91phox was dose-dependent. Meanwhile, the cytoplasmic subunit p47phox was translocated to the cell membrane and localized with p22phox and gp91phox to form reactive NADPH oxidase. Our data suggest, for the first time, that NADPH oxidase-mediated generation of ROS is an important contributor to X-ray-induced cell death. This suggests a new target for combined gene transfer and radiotherapy. 相似文献
60.
Lu WJ Yang Q Sun W Woods SC D'Alessio D Tso P 《American journal of physiology. Gastrointestinal and liver physiology》2008,294(5):G1130-G1138
Glucose-dependent insulinotropic polypeptide (GIP) is an important incretin produced in the K cells of the intestine and secreted into the circulating blood following ingestion of carbohydrate- and fat-containing meals. GIP contributes to the regulation of postprandial insulin secretion and is essential for normal glucose tolerance. We have established a method of assaying GIP in response to nutrients using the intestinal lymph fistula model. Administration of Ensure, a mixed-nutrient liquid meal, stimulated a significant increase in intestinal lymphatic GIP levels that were approximately threefold those of portal plasma. Following the meal, lymph GIP peaked at 60 min (P < 0.001) and remained elevated for 4 h. Intraduodenal infusions of isocaloric and isovolumetric lipid emulsions or glucose polymer induced lymph GIP concentrations that were four and seven times the basal levels, respectively. The combination of glucose plus lipid caused an even greater increase of lymph GIP than either nutrient alone. In summary, these findings demonstrated that intestinal lymph contains high concentrations of GIP that respond to both enteral carbohydrate and fat absorption. The change in lymphatic GIP concentration is greater than the change observed in the portal blood. These studies allow the detection of GIP levels at which they exert their local physiological actions. The combination of glucose and lipid has a potentiating effect in the stimulation of GIP secretion. We conclude from these studies that the lymph fistula rat is a novel approach to study in vivo GIP secretion in response to nutrient feeding in conscious rats. 相似文献