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肿瘤的发生、发展和治疗与机体免疫系统功能密切相关,伴随着肿瘤抗原、抗原递呈、T细胞识别机制的突破性研究进展,研究者发现抗肿瘤多肽疫苗能够通过肿瘤抗原多肽识别抗原递呈细胞表面的主要组织相容性复合体(MHC)分子,形成肽-MHC-T细胞受体复合物,引起相应的细胞毒性T淋巴细胞免疫反应,从而杀伤肿瘤。因此,研制既能打破肿瘤患者存在的免疫耐受又能诱发针对肿瘤相关抗原特异性免疫应答的高效多肽疫苗已成为肿瘤免疫治疗研究的热点。论文综述了肿瘤多肽疫苗抗肿瘤相关机制及其在该领域所取得的最新临床研究进展。 相似文献
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表位(epitope)又称抗原决定簇(antigenic determinant),是指存在于抗原分子表面的能够决定抗原特异性的数个氨基酸残基组成的特殊序列及其空间结构。根据与抗原受体结合不同分为B细胞(识别)表位和T细胞(识别)表位。 T细胞表位就是抗原蛋白中经抗原提呈细胞(antigenprocessing cell,APC)处理,由MHC分子提呈给T淋巴细胞受体的多肽片段。确定T细胞表位,对于研究细胞免疫的机理、过程及研制亚单位多肽疫苗和基因疫苗具有重要的意义。目 相似文献
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多肽表位作为抗原的重要组成成分,可以被宿主免疫系统B细胞产生的抗体（Ig）和T细胞受体（TCR）识别,从而诱导机体产生免疫保护作用。传统的研究方法如交叠肽合成等费时费力,极大地限制了多肽表位的研究。随着生物信息学、高通量测序、CRISPR/Cas9、质谱（MS）等技术出现以及TAP非依赖型蛋白加工机制的不断阐述,使表位的研究得到不断完善。作者介绍了最新的多肽表位研究方法,包括利用计算机对B细胞和T细胞表位的预测、基于MHC与抗原肽结构作用为基础的方法、结合高通量测序技术的表位筛选方法、结合新型基因编辑技术的表位筛选方法、TAP非依赖性T细胞表位的最新研究等,并对今后多肽表位研究的发展进行了展望。 相似文献
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细胞的抗原表位研究方法 总被引：3，自引：0，他引：3
多表位疫苗有望成为预防多种病原体感染的理想疫苗,因而被认为是将来疫苗的发展方向。抗原表位是研究抗原的免疫机制和表位疫苗的基础,近年来在表位研究方面取得了一些可喜的进展,特别是抗原表位的研究方法。B细胞表位的研究方法已经不局限于通过交叠合成多肽进行研究,又诞生了噬菌体随机肽库以及表位预测等方法;在T细胞抗原表位的研究方面也有了相应的预测方法,尤其是将ELISPOT试验、体外抗原提呈试验等应用于T细胞表位活性的鉴定,极大的促进了T细胞表位的研究进展。文章全面系统地对B细胞表位与T细胞表位的研究方法的进展进行了综述。旨在为表位和表位疫苗的研究提供先进的多种技术方法。 相似文献
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为了对新城疫病毒（Newcastle disease virus,NDV）的细胞毒性T细胞（cytotoxic T cell,CTL）表位进行研究,本研究通过在线分析软件预测了NDV弱毒株La Sota和强毒株Herts/33 NP蛋白的MHC I类分子限制性表位,共获得9条可能的表位多肽序列,并人工合成了这些短肽。分别构建了含有La Sota和Herts/33 NP基因的DNA重组质粒并免疫4周龄SPF级C57BL/6小鼠,首免后21 d加强免疫1次,二免后10 d无菌采集脾脏制备脾淋巴细胞悬液,采用ELISpot法测定预测多肽诱导脾淋巴细胞分泌IFN-γ的能力,根据分泌IFN-γ形成的特异性斑点数进行生物统计学分析,发现2条多肽产生的斑点数显著高于无关肽刺激组（P＜0.01）。确定了针对小鼠H-2 kb的限制性T细胞抗原表位的2条多肽。这些可用于合成特异性的MHC-肽四聚体,为后续研究NDV与树突状细胞（dendritic cells,DC）及T淋巴细胞之间的免疫抑制机制提供重要保障。 相似文献
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为评价猪口蹄疫合成肽疫苗免疫猪后的细胞免疫应答,用含有E、F两种多肽抗原的猪口蹄疫合成肽疫苗免疫猪,二免后两周采血分离猪外周血淋巴细胞,再用E、F两种合成肽及二者混合物对淋巴细胞刺激培养48 h,用MTT法检测特异性T淋巴细胞增殖反应。结果显示,在抗原E、F混合物浓度为50μg/mL时,抗原对免疫组淋巴结细胞的刺激增殖作用显著高于未免疫对照组（P〈0.01）。表明,该猪口蹄疫合成肽疫苗免疫猪能有效引起特异性T淋巴细胞免疫应答。 相似文献
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热应激蛋白（heat stress proteins，HSPs）是机体受到应激原的刺激后产生的几族（如HSP70家族、HSP90家族等）高度保守的蛋白质，对维持细胞生存和内环境的稳定起重要作用。其中HSP70家族的HSP70是研究最多的，因为它在大多数生物中含量最多，在细胞应激后生成最显著。HSP70是机体一种重要的非特异性细胞保护蛋白，具有多种生物学功能，如分子伴侣，抗细胞凋亡，抗氧化作用，此外在免疫反应中也起重要作用。HSP70-肽疫苗是HSP70和抗原多肽结合形成的复合物，它可以直接从肿瘤组织或肿瘤细胞系中提取得到，即HSP70-肽肿瘤疫苗；也可以采用生物工程技术的方法在体外表达HSP70，再与已知的抗原多肽交联得到。其中HSP70-肽肿瘤疫苗是研究最多的，已成为肿瘤研究的一个重要内容，HSP70-肽肿瘤疫苗的可行性在实验动物已得到证实，显示了良好的应用前景。 相似文献
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Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks. 相似文献
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Davis MS Willard MD Nelson SL Mandsager RE McKiernan BS Mansell JK Lehenbauer TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):311-314
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large. 相似文献
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Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses. 相似文献
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Waruiru RM Thamsborg SM Nansen P Kyvsgaard NC Bogh HO Munyua WK Gathuma JM 《Tropical animal health and production》2001,33(3):173-187
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round. 相似文献
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The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host. 相似文献
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Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ 
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下载免费PDF全文 S. Pashaei T. Ghoorchi A. Yamchi 《Journal of animal physiology and animal nutrition》2016,100(2):211-216
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed. 相似文献
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Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb
albumin
- ALT
alanine aminotransferase
- AST
aspartate aminotransferase
- BUN
blood urea nitrogen
- Chol
cholesterol
- Glob
globulin
- -GT
-glutamyl transpeptidase
- IP
inorganic phosphorus
- TP
total protein 相似文献
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正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in 相似文献
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Tropical Animal Health and Production - 相似文献