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排序方式: 共有6919条查询结果,搜索用时 15 毫秒
41.
42.
Wei-Ping Ma Shi-Ning Yin Jia-Peng Chen Xi-Cheng Geng Ming-Fei Liu Hai-Hua Li Ming Liu Hong-Bing Liu 《Marine drugs》2022,20(3)
Hematopoietic damage is a serious side effect of cytotoxic drugs, and agents promoting hematopoiesis are quite important for decreasing the death rate in cancer patients. In our previous work, we prepared the simulated digestive product of fucoidan from Sargassum fusiforme, DSFF, and found that DSFF could activate macrophages. However, more investigations are needed to further evaluate whether DSFF could promote hematopoiesis in the chemotherapy process. In this study, the protective effect of DSFF (1.8–7.2 mg/kg, i.p.) on cyclophosphamide-induced hematopoietic damage in mice and the underlying mechanisms were investigated. Our results show that DSFF could restore the numbers of white blood cells, neutrophils, and platelets in the peripheral blood, and could also retard bone marrow cell decrease in mice with cyclophosphamide-induced hematopoietic damage. UPLC/Q-Extraction Orbitrap/MS/MS-based lipidomics results reveal 16 potential lipid biomarkers in a serum that responded to hematopoietic damage in mice. Among them, PC (20:1/14:0) and SM (18:0/22:0) were the key lipid molecules through which DSFF exerted protective actions. In a validation experiment, DSFF (6.25–100 μg/mL) could also promote K562 cell proliferation and differentiation in vitro. The current findings indicated that DSFF could affect the blood cells and bone marrow cells in vivo and thus showed good potential and application value in alleviating the hematopoietic damage caused by cyclophosphamide. 相似文献
43.
科学预测人口城市化水平,对相关政策的制定、制度的改革、城市配套设施的建设以及解决就业问题都具有重要意义。本文以乌兰察布市为例,对地区总人口进行预测的基础之上,运用劳动力结构模型、劳动力地域转移模型等多种数学模型,预测了城镇人口城市化水平和非农业人口的城市化水平。最后,选取与城市化相关的七项指标,对城市化水平进行了综合预测。 相似文献
44.
Epidemiology and control of brucellosis in China 总被引:8,自引:0,他引:8
The paper describes the history and evolvement of brucellosis in China. It presents the variation of epidemic situation, epidemiological characteristics, application of vaccines and control in brief. Before 1980s, human and animal brucellosis was quite severe; during 1980s, the incidence of human and animal brucellosis was relatively low, and seemed to decrease during the decade. During 1990s, there were no obvious changes in the incidence of animal brucellosis, but the incidence of human brucellosis increased, especially from 1995 to 2001. There are not only some common characteristics but also some differences in brucellosis epidemiology relative to that reported in the rest of the world. For the entire country, B. melitensis was the predominant strain associated with outbreaks, and the epidemic peak is from February to June. Several Brucella vaccines have been used in China for prevention and control of brucellosis. such as B. abortus 104 M in humans, B. suis S2 in animals. The introduction of comprehensive measures has allowed great progress in the prevention and control of brucellosis in China. Surveillance points were set-up countrywide to estimate the epidemic situation. In addition, we discussed the new characteristics of brucellosis in China, the influence of the El Nino phenomenon on brucellosis epidemic situation, the phenomenon of antigenic interference between Brucella species and some disadvantages of live Brucella vaccines. 相似文献
45.
Effect of simulated transport stress on the rat small intestine: A morphological and gene expression study 总被引:2,自引:0,他引:2
Changrong Wan Peng Yin Xiaolong Xu Mingjiang Liu Shasha He Shixiu Song Fenghua Liu Jianqin Xu 《Research in veterinary science》2014
The present study investigated the effects of simulated transport stress on morphology and gene expression in the small intestine of laboratory rats. Sprague Dawley rats were subjected to 35 °C and 0.1×g on a constant temperature shaker for physiological, biochemical, morphological and microarray analysis before and after treatment. The treatment induced obvious stress responses with significant decreases in body weight (P < 0.01), increases in rectal temperature, serum corticosterone (CORT), serum glucose (GLU), creatine kinase (CK) and lactate dehydrogenase (LDH) levels (P < 0.01), as well as expression of Hsp27/70/90 mRNA (P < 0.05; P < 0.01). The rat jejunum was severely damaged and apoptotic after mimicking transport stress, which may mainly be related to cell death, oxidation reduction and hormone imbalance determined by microarray analysis. The bioinformatics analysis from the present study would provide insight into the potential mechanisms underlying transport stress-induced injury in the rat small intestine. 相似文献
46.
法氏囊活性肽对鸡体增重及饲料转化率的影响 总被引:3,自引:0,他引:3
把不同剂量的法氏囊活性肽 (BS)冻干粉与传染性法氏囊病 (IBD)活苗混合后 ,对 2 1日龄SPF鸡滴鼻点眼 ,同时另选一批同样生长状态的鸡 ,在颈部皮下接种IBD细胞毒油苗 ,同时肌肉注射上述不同剂量法氏囊活性肽 ,观察法氏囊活性肽对鸡生长性能的影响。结果发现 :免疫后7d ,活苗 0 2mLBS组增长最快 ,比免疫对照组多增 82 5 % ,并且饲料报酬高。但从整个试验期看 ,0 4mLBS组增重效果较好 ,比免疫对照组多增 1 9 8% ,并且有较高的饲料转化率。而肌肉注射BS组中 ,高剂量 (0 8mL)BS组的增重效果一直很好 ,比对照组总增重平均多增 7 2 3 % ,并有较高的饲料报酬。这说明滴鼻点眼或是肌肉注射 ,BS都有促生长的作用 相似文献
47.
药物代谢动力学猪链球菌病模型的研制 总被引:8,自引:0,他引:8
为研制适于猪的药物代谢动力学研究的传染病模型,取长白×杜洛克杂种猪16头(体重32.0±0.7kg),每猪皮下接种纯净猪链球菌(C74-41型)12.5亿个活菌,复制出典型的亚急性型猪链球菌病。动物经感染后1d体温持续升高1.5~2.0℃。血浆总蛋白含量开始持续降低(P<0.01),血清肌酐浓度则开始升高(P<0.05)。感染后2.5d,磺溴酞的消除半衰期和给药后15min的滞留率均下降(P<0. 相似文献
48.
Zirui Zhou Jie Zhang Xianlian Zhang Shilan Mo Xian Tan Lixia Wang Jianzhong Li Yali Li Xueqin Ding Xianyong Liu Xingqun Ma Huansheng Yang Yulong Yin 《Journal of animal physiology and animal nutrition》2019,103(5):1530-1537
Weaning process widely affects the small intestinal structure and function in piglets, while the responses of large intestine to weaning stress are still obscure. The purpose of this study was to determine the developmental changes (i.e., short chain fatty acids (SCFAs) concentrations, growth parameters, crypt‐related indices and antioxidant capacity) in colon of piglet during weaning. Forty piglets were weaned at day 21 and euthanized to collect colonic tissues and digesta samples on day 0, 1, 3, 7 and 14 post‐weaning (n = 8). Piglet growth performance was improved (p < .001) on day 7 and 14 post‐weaning. The concentrations of acetate, propionate, butyrate, valerate, isobutyrate, isovalerate and total SCFAs were higher (p < .001) during the late post‐weaning period. The mRNA abundances of SCFAs transporters were greater (p < .001) on day 7 and 14. The absolute and relative weights, absolute length and perimeter of colon were greater (p < .001) on day 7 and 14. Similarly, post‐weaning increases (p < .001) in colonic crypt depth and Ki67 positive cells numbers per crypt were observed during the same period. Colonic crypt fission indices decreased (p < .01), while total crypt numbers increased (p < .001) on day 14 after weaning. Moreover, total SCFAs concentration was significantly associated with colonic growth parameters and Ki67 cells/crypt (p < .001). In addition, catalase content was decreased on day 3, 7, and 14, whereas, the concentrations of total superoxide dismutase (T‐SOD) and manganese‐containing superoxide dismutase (MnSOD) were higher (p < .05) on day 1 and 3 post‐weaning. These results showed that weaning process has a significant effect on colonic growth and development, which might be associated with the change of SCFAs concentrations in colon. 相似文献
49.
2020年10月,宁夏盐池县、利通区、平罗县发生输入性牛结节性皮肤病疫情。为查明疫情发生原因,分析疫情扩散风险,宁夏回族自治区农业农村厅畜牧兽医局组织成立督导组进行流行病学调查。通过现场调查、座谈及实验室检测,综合发病、溯源和追踪情况以及实验室检测结果,分析认为此次疫情是由调入纯种荷斯坦育成奶牛引起的。因及时采取了封锁疫点、控制移动、扑杀、无害化处理、清洗消毒、杀灭蚊蝇、免疫等综合处置措施,疫情扩散风险较低。此次疫情警示,要强化牛只及其产品的调运监管,加强疫情排查监测,及时发现和处置疫情。 相似文献
50.
Aihong Liu Guiquan Guan Pengfei Du Huitian Gou Jun Zhang Zhijie Liu Milin Ma Qiaoyun Ren Junlong Liu Jifei Yang Youquan Li Qinli Niu Qi Bai Hong Yin Jianxun Luo 《Veterinary parasitology》2013,191(1-2):15-22
The present study developed and validated a species-specific loop-mediated isothermal amplification (LAMP) assay for the rapid detection and discrimination of two benign bovine Theileria species – T. sergenti and T. sinensis. The LAMP assay is inexpensive and easy to perform and involves a rapid reaction-the amplification can be performed in 55 min or 50 min under isothermal conditions of 61 °C or 63 °C, respectively, by employing a set of four species-specific primer mixtures. The results can be checked using agarose gels. The optimal assay conditions, under which the assay exhibited with no cross-reaction with other closely related tick-borne parasites (T. annulata, Babesia bovis, B. bigemina, B. major, B. ovata, B. U. sp., Anaplasma marginale) or between the two Theileria species of interest, was established. The assay is approximately 10-fold more sensitive than the conventional specific PCR assay. The LAMP assay was validated using DNA from 6 standard stocks in the laboratory and was evaluated for its diagnostic utility using blood samples collected from experimentally and naturally infection cattle or yaks in China. These findings indicate that this Theileria species-specific LAMP assay may have potential clinical applications for the detection and differentiation of two benign bovine Theileria species – T. sergenti and T. sinensis, especially in endemic countries. 相似文献