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111.
硅肺是吸入SiO2粉尘引起的以肺间质纤维化为主的全身性疾病。探讨了白茶提取物对纳米SiO2诱导大鼠肺纤维化的抑制作用及机制。54只Wistar大鼠随机分为正常组、模型组、白毫银针提取物组、白牡丹提取物高和低剂量组、EGCG组共6个组,每组9只大鼠。除正常组外的其余5个组采用非暴露式气管插管方法造模纳米SiO2粉尘(80 mg·mL-1),每天以灌胃方式给予药物两周之后,检测肺组织中羟脯氨酸(HYP)、一氧化氮(NO)、超氧化物歧化酶(SOD)、丙二醛(MDA)和谷光甘肽过氧化物酶(GSH-Px)含量以及肺组织形态学变化。结果显示,与模型组相比,白茶提取物各处理组及EGCG组病理形态改变有不同程度的减轻,其中白毫银针提取物组的效果最佳。白茶提取物各处理组与EGCG组的大鼠肺NO含量和炎症因子IL-6都显著低于模型组(P<0.05),GSH-Px活力高于模型组(P<0.05),高剂量白牡丹提取物对降低NO含量和升高GSH-Px活力效果最好;本研究表明,白茶提取物对于纳米SiO2引起的大鼠肺纤维化氧化应激损伤具有有效的减缓和修复作用,主要与其抗氧化作用和抑制炎症反应相关。  相似文献   
112.
This study aimed to investigate the effect of mydriasis using topical rocuronium bromide on electroretinography (ERG) in domestic pigeons (Columba livia). Scotopic mixed rod and cone, photopic cone, and photopic flicker ERG were performed on nine eyes of nine healthy adult pigeons under sedation. Each pigeon underwent two sets of ERG recordings. First, without the induction of mydriasis (control) and the second time with the induction of mydriasis using topical rocuronium bromide (treatment). The results were compared using either the Student’s t-test or Wilcoxon rank-sum test, where a P-value of <0.05 was considered statistically significant. No significant differences were observed in the a- and b-wave implicit times and amplitudes during scotopic ERG between the two groups. The a- and b-wave amplitudes in the photopic cone were significantly higher in the treatment group (63.83 ± 32.33 and 191.75 ± 94.46 µV) compared to the control group (46.15 ± 27.60 and 116.76 ± 70.65 µV; P=0.045 and P=0.032, respectively). The photopic flicker amplitude was also significantly higher in the treatment group (76.23 ± 48.56 µV) than in the control group (42.18 ± 31.18 µV; P=0.044). No statistically significant differences were observed in the photopic cone and flicker implicit times between both groups. In conclusions, mydriasis induced by rocuronium bromide in pigeon resulting in higher amplitudes during the photopic ERG but not scotopic ERG.  相似文献   
113.
Seventeen soybean cultivars were screened to discern differences in aluminum (Al) sensitivity. The Sowon (Al-tolerant) and Poongsan (Al-sensitive) cultivars were selected for further study by simple growth measurement. Aluminum-induced root growth inhibition was significantly higher in the Poongsan cultivar than in the Sowon cultivar, although the differences depended on the Al concentration (0, 25, 50, 75 or 100 μmol L–1) and the amount of exposure (0, 3, 6, 12 or 24 h). Damage occurred preferentially in the root apex. High-sensitivity growth measurements using India ink implicated the central elongation zone located 2–3 mm from the root apex. The Al content was lower 0–5 mm from the root apices in the Sowon cultivar than in the apices of the Poongsan cultivar when exposed to 50 μmol L–1 Al for 12 h. Furthermore, the citric acid exudation rate was more than twofold higher in the Sowon cultivar. Protein production of plasma membrane (PM) H+-ATPase from the root apices (0–5 mm) was upregulated in the presence of Al for 24 h in both cultivars. This activity, however, decreased in both cultivars treated with Al and the Poongsan cultivar was more severely affected. We propose that Al-induced growth inhibition is correlated with changes in PM H+-ATPase activity, which is linked to the exudation of citric acid in the root apex.  相似文献   
114.
为探讨5-氟尿嘧啶的药效、毒性与给药剂量之间的关系,采用BALB/c小鼠来源的CT26结肠癌细胞株构建小鼠结肠癌模型,分别给予10、20、30和50 mg/kg剂量的5-氟尿嘧啶,分析其抗肿瘤效果、对小鼠体质量的影响和死亡率等指标.结果表明,5-氟尿嘧啶的体内抑瘤效果及毒性与剂量密切相关.综合分析评价各指标,认为20~30 mg/kg剂量的5-氟尿嘧啶较适合于小鼠结肠癌模型中的药效评价.  相似文献   
115.
We investigated the influence of pneumoperitoneum#(PP) and postural change under inhalation anesthesia with isoflurane, which is routinely used in dogs, on the cardiovascular and respiratory systems. As test animals, 6 adult beagles were used. To induce anesthesia, atropine, butorphanol and propofol were intravenously injected. Anesthesia was maintained with 1.3 MAC (1.7%) isoflurane. The following were the experiment conditions: I:E ratio, 1:1.9; tidal air exchange, 20 ml/kg; and ventilation frequency, 14 times/min. Respiration was regulated so that the PaCO2 was approximately 35 to 40 mmHg before the start of the experiment. PP with CO2 (intraperitoneal pressure 15 mmHg) and a postural change (15°C) was performed during the experiment. As parameters of circulatory kinetics, heart rate (HR), mean aortic pressure (MAP), mean pulmonary arterial pressure (MPAP), central venous pressure (CVP), femoral venous pressure (FVP) and cardiac output (CO) were measured. As parameters of respiratory kinetics, airway pressure (PAW) and blood gas (BG) were measured. There were significant increases in HR, MAP, MPAP, CVP, FVP, CO, PAW and PaCO2 after PP in the horizontal position. There were significant increases in CVP, FVP, PAW and PaCO2 after PP in the Trendelenburg position. There were significant increases in the MPAP, CVP, FVP, PAW and PaCO2 after PP in the inverse Trendelenburg position. There was a significant difference in FVP after PP between the Trendelenburg position and inverse Trendelenburg position. The results of this experiment suggest that appropriate anesthesia control, such as changing the ventilation conditions after PP, is required for laparoscopic surgery under inhalation anesthesia with isoflurane.  相似文献   
116.
Niemann-Pick type C disease (NP-C) is a rare and ultimately fatal lysosomal storage disorder with variable neurologic symptoms. Loss of neuronal function and neuronal cell death occur in the NP-C brain, similar to the findings for other neurodegenerative diseases. Targeting of neuronal cells in the brain therefore represents a potential clinical intervention strategy to reduce the rate of disease progression and improve the quality of life. We previously reported that bone marrow stem cells show a neurogenic effect through CCL2 (also known as monocyte chemoattractant protein-1, MCP-1) secretion in the brains of NP-C mice. However, the direct effect of CCL2 on neurogenesis has not been ascertained. Here, to define neurogenic effects of CCL2 in NP-C, we applied human recombinant CCL2 to neural stem cells (NSCs) derived from NP-C mice. CCL2-treated NSCs showed significantly increased capacity for self-renewal, proliferation and neuronal differentiation. Similar results were observed in the subventricular zone of NP-C mice after CCL2 treatment. Furthermore, infusion of CCL2 into the NP-C mouse brain resulted in reduction of neuroinflammation. Taken together, our results demonstrate that CCL2 is a potential new therapeutic agent for NP-C.  相似文献   
117.
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2) and total body clearance (CLB) of i.v. MRFX were 6.87 hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr, respectively, and the corresponding values for i.m. administration of MRFX were 5.07 hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr. The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data obtained in the present study and previously reported minimum inhibitory concentration (MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were 2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route.  相似文献   
118.
Intracranial hemangioma is a rare intraaxial hemorrhagic neoplasm with imaging characteristics similar to other intracranial hemorrhagic lesions. We describe two canine cerebral hemangiomas that appeared as poorly circumscribed intraaxial compressive lesions that were predominantly hypointense on T2 sequences and heterogeneously contrast enhancing. Both lesions had perilesional edema and were hypointense on T2*‐gradient recalled echo sequences, consistent with hemorrhage. In one tumor a short partial peripheral rim was present, which was suggestive of hemosiderin deposition. Cerebral hemangioma should be included as a differential for hemorrhagic intracranial lesions.  相似文献   
119.
To preserve Jeju black cattle (JBC; endangered native Korean cattle), a pair of cattle, namely a post-death cloned JBC bull and cow, were produced by somatic cell nuclear transfer (SCNT) in a previous study. In the present study, we examined the in vitro fertilization and reproductive potentials of these post-death cloned animals. Sperm motility, in vitro fertilization and developmental capacity were examined in a post-death cloned bull (Heuk Oll Dolee) and an extinct nuclear donor bull (BK94-13). We assessed reproductive ability in another post-death cloned cow (Heuk Woo Sunee) using cloned sperm for artificial insemination (AI). There were no differences in sperm motility or developmental potential of in vitro fertilized embryos between the post-death cloned bull and its extinct nuclear donor bull; however, the embryo development ratio was slightly higher in the cloned sperm group than in the nuclear donor sperm group. After one attempt at AI, the post-death cloned JBC cow became pregnant, and gestation proceeded normally until day 287. From this post-death cloned sire and dam, a JBC male calf (Heuk Woo Dolee) was delivered naturally (weight, 25 kg). The genetic paternity/maternity of the cloned JBC bull and cow with regard to their offspring was confirmed using International Society for Animal Genetics standard microsatellite markers. Presently, Heuk Woo Dolee is 5 months of age and growing normally. In addition, there were no significant differences in blood chemistry among the post-death cloned JBC bull, the cow, their offspring and cattle bred by AI. This is the first report showing that a pair of cattle, namely, a post-death cloned JBC bull and cow, had normal fertility. Therefore, SCNT can be used effectively to increase the population of endangered JBC.  相似文献   
120.
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