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1.
首次应用ＸＸＧ－Ａ型心血管功能测试仪对２９头健康成年黄牛和２８头热证黄牛部分血液动力学指标进行了无创检测和分析。与正常黄牛相比，热证组ＣＯ（Ｐ＜０．００１），ＣＩ（Ｐ＜０．００１），ＰＲ（Ｐ＜０．００１），ＶＰＥ（Ｐ＜０．０５），ＥＷＫ（Ｐ＜０．００１），ＨＯＩ（Ｐ＜０．０５），ＬＶＷＩ（Ｐ＜０．０５），ＰＰ（Ｐ＜０．００１），ＢＬＫ（Ｐ＜０．００１），ＡＣ，ＢＶ，ＭＨＲ（Ｐ＜０．００１）等指标均有不同程度的升高；而ＴＰＲ（Ｐ＞０．０５），ＭＲＴ（Ｐ＜０．００１），ＭＳＴ（Ｐ＜０．０１）都有明显的下降。结果表明，血液循环的高切变态和心血管机能兴奋是热证黄牛的重要特征。  相似文献   

2.
首次应用无创检测技术对１８例寒证黄牛的２３项血液动力流变学指标进行了检测：ＰＲ，ＳＶ，ＣＯ，ＳＩ，ＣＩ，ＶＰＥ，ＬＶＷＩ，ＦＥＫ和ＡＣ等心血管动力学指标均有不同程度的降低，其中ＰＲ，ＣＯ，ＣＩ和ＦＥＫ变化显著（Ｐ＜０．０５），η，ＭＨＲ，ＭＲＴ，ＭＳＴ等流变学指标变化明显（Ｐ＜０．０５—０．０１），呈现微循环瘀滞和高粘血症。  相似文献   

3.
本文通过给山羊静注大肠杆菌内毒素诱导内毒素休克,探讨内毒素休克时血液流变性的变化规律,并观察山莨菪碱（６５４－２）对其影响。结果表明,山羊内毒素休克时,低切率全血比粘度（ＬＢＶ）和低切率全血还原比粘度（ＬＢＲＶ）明显升高（Ｐ＜０．０５）,血浆比粘度（ＰＶ）和红细胞聚集指数（ＡＩ）均显著增高（Ｐ＜０．０１,Ｐ＜０．０５）,红细胞变形能力（ＲＣＤ）显著下降（Ｐ＜０．０５,Ｐ＜０．０１）,当静注内毒素前１０ｍｉｎ给予６５４－２（２．５ｍｇ／ｋｇ）山羊的ＬＢＶ和ＬＢＲＶ在１～５ｈ显著高于对照组,５ｈ前ＰＶ和ＡＩ值比对照组有明显升高,第７ｈ后与对照组间无明显差异（Ｐ＞０．０５）,且显著低于休克组（Ｐ＜０．０５）,其ＲＣＤ亦趋于正常。提示山羊内毒素休克时血液流变参数明显改变,血液粘度增加,红细胞聚集加剧,而应用６５４－２具有显著改变血液状态,缓解微循环障碍发生。  相似文献   

4.
３日龄肉用ＡＡ雏鸡成髓细胞性白血病强毒（ｖＡＭＶ）人工感染后,鸡成髓细胞性白血病（ＡＭＢ）发病率８６．７％、死亡率７０％,脾脏、胸腺、法氏囊、心脏、肝脏、肾脏和性腺超氧化物歧化酶（ＳＯＤ）活性与健康对照雏鸡相比,Ｔ－ＳＯＤ和Ｍｎ－ＳＯＤ活性于１０日龄时均极显著升高（Ｐ＜０．０１）,于１７日龄时则极显著下降（Ｐ＜０．０１）,以后日龄亦有明显降低（Ｐ＜０．０５,Ｐ＜０．０１）,而Ｃｕ,Ｚｎ－ＳＯＤ活性于１０和２４日龄无明显变化（Ｐ＞０．０５）、１７日龄时显著或极显著降低（Ｐ＜０．０５,Ｐ＜０．０１）,３０日龄则明显升高（Ｐ＜０．０５,Ｐ＜０．０１）。  相似文献   

5.
中药制剂产后康复宁的药理研究   总被引：2，自引：0，他引：2  
应用ＬＭＳ－２Ｂ二道生理记录仪及配套装置,通过免疫器官重量法和鸡红细胞（ＣＲＢＣ）作免疫原的溶血素（ＩｇＭ）测定法及体内抑菌试验法,观测了中药制剂产后康复宁对家兔离体、在位子宫和小鼠免疫功能的影响,以及对感染大肠杆菌Ｋ８８小鼠的保护作用。结果表明,产后康复宁可使兔离体子宫收缩频率显著增加（Ｐ＜０．０１）,张力显著增强（Ｐ＜０．０１）,振幅显著增高（Ｐ＜０．０１）;与麦角相比,仅５ｍｉｎ相同时间的子宫收缩频率差异明显（Ｐ＜０．０５）,其余相同时间子宫收缩频率、张力、振幅均无明显差异（Ｐ＞０．０５）。使在位子宫收缩频率明显增加（Ｐ＜０．０５）,张力明显增强（Ｐ＜０．０５）,振幅明显增高（Ｐ＜０．０５）;与麦角比较,子宫收缩频率、张力、振幅在５、１０ｍｉｎ相同时间内差异均不明显（Ｐ＞０．０５）。对免疫功能的影响,不但使小鼠脾脏显著增重（Ｐ＜０．０１）,而且溶血素明显增多（Ｐ＜０．０５）。对感染大肠杆菌Ｋ８８的小鼠有明显的保护作用（Ｐ＜０．０５）。提示产后康复宁有增强子宫收缩,促使宫内恶露排除,加速子宫复旧,增强机体免疫功能等作用。  相似文献   

6.
在配种期饲喂金霉素对母猪繁殖性能的影响   总被引：1，自引：0，他引：1  
本研究选用４０头母猪进行配种期饲喂金霉素试验，以估价配种期喂金霉素对母猪繁殖性能的影响。结果显示：配种期母猪饲喂含金霉素２００ｍｇ／ｋｇ饲料的日粮增加母猪体重。与对照组相比，配种期（Ｐ＜０．０５）、怀孕１１０天（Ｐ＜０．０１）、产仔后２４小时（Ｐ＜０．０１）、产仔后２１天（Ｐ＜０．０５）和断奶期（Ｐ＜０．０１）母猪体重显著增加；除怀孕增重外，分娩失重和哺乳失重略高（Ｐ＞０．０５）；哺乳期饲料摄入降低（Ｐ＜０．０５）；配种受孕率略高。配种期母猪饲喂金霉素显著提高每窝产仔数（Ｐ＜０．０５），出生时、２１日龄和断奶时存活仔猪数都略高于对照组（Ｐ＞０．０５）。出生时存活仔猪体重、２１日龄仔猪体重都略低于对照组（Ｐ＞０．０５），断奶时仔猪体重略高于对照组。断奶至发情的间隔略长于对照组。结论：配种期母猪饲喂金霉素可提高繁殖性能。  相似文献   

7.
对３头实验性肠阻塞驴和１０匹自然肠阻塞马、骡进行了血气分析。结果表明：（１）实验性肠阻塞驴在造型后２４小时，血液ｐＨ、ＰＯ２、ＰＣＯ２、Ｏ２Ｓ比造型前略低（Ｐ＞０．０５），ＨＣＯ－３、ＴＣＯ２、ＢＥ、ＳＢＥ、ＳＢＣ比造型前明显低（Ｐ＜０．０５，Ｐ＜０．００１），治愈时血气指标趋于正常；（２）自然肠阻塞马、骡在接受治疗前，上述９项血气指标变化与实验性肠阻塞（造型后２４小时）驴大致相同，治疗后２４小时，马、骡的绝大多数血气指标呈继续下降趋势，治愈时血气指标亦趋于正常。  相似文献   

8.
驴,骡血气分析初探   总被引：3，自引：2，他引：1  
对２５头驴、骡进行血气分析，结果表明：驴、骡血液ｐＨ，Ｐｏ＿２，Ｏ＿２ＳＴ，ＨＣＯ，Ｔｃｏ＿２，ＢＥ＿ｂ，ＳＢｃ，ＢＥ＿（ｅｃｆ）在二者之间无显著差异性（Ｐ＞０．０５）；驴血液Ｐｃｏ＿２，和乳酸皆高于骡（Ｐ＜０．０１和Ｐ＜０．０５）；驴、骡的血液ｐＨ为７．４１±０．０３，Ｐｏ＿２为４．９７±０．９７ｋＰａ，Ｐｃｏ＿２为５．２０±０．３９ｋＰａ，Ｏ＿２ＳＴ为７１．２９±９．２５％，ＨＣＯ＿３为２５．９４±１．６８ｍｍｏｌ／Ｌ，Ｔｃｏ＿２为２７．１５±１．７３ｍｍｏｌ／Ｌ，ＢＥ＿ｂ为１．９６±１．７１ｍｍｏｌ／Ｌ，ＳＢｃ为２５．６８±１．３１ｍｍｏｌ／Ｌ，ＢＥ＿（ｅｃｆ）为１．２３±１．８９ｍｍｏｌ／Ｌ，乳酸含量为１．６８±０．６３ｍｍｏｌ／Ｌ。  相似文献   

9.
３日龄雏鸡禽成髓细胞性白血病强毒（ｖＡＭＶ）人工感染后,禽成髓细胞性白血病（ＡｖｉａｎＭｙｅｌｏｂｌａｓｔｏｓｉｓ,ＡＭＢ）发病率８６．７％,死亡率７０％;雏鸡ｖＡＭＶ感染１０日龄脾脏、胸腺、法氏囊、心脏、肝脏、肾脏和性腺组织中指质过氧化物（ＬＰＯ）含量高于（Ｐ＞０．０５）或显著高于（Ｐ＜０．０５,Ｐ＜０．０１）健康对照雏鸡;１７日龄后各器官组织中ＬＰＯ含量则低于（Ｐ＞０．０５）或显著低于（Ｐ＜０．０５,Ｐ＜０．０１）健康对照雏鸡。  相似文献   

10.
采用 １,６二苯基１,３,５己三烯（１,６ｄｉｐｈｅｎｙｌ１,３,５ｈｅｘａｔｒｉｅｎｅ, Ｐ Ｈ, Ｓｉｇｍ ａ Ｃｈｅｍ ｉｃａｌ Ｃｏ）分子荧光偏振法研究了内毒素诱导山羊红细胞膜的流动性（ Ｐ）,膜脂区微粘度（η）及脂双层分子排列有序性系数（ Ａ）的变化及６５４２ 的影响。结果表明, Ｅ Ｔ 处理组（Ⅱ组） Ｅ Ｃ Ｍ 的 Ｐ、和 Ａ参数除在１ｈ 高于对照组（Ⅰ组）和６５４ Ｚ２处理（Ⅲ组）且差异不显著（ Ｐ＞ ０．０５）外,在 ３,５,７,９,１２ｈ 均高于Ⅰ组和Ⅲ组（ Ｐ＜０．０５）, Ｐ＜ ０．０１）;Ⅲ组 Ｐ、和 Ａ 参数在１ ｈ低于Ⅰ组且差异不显著（ Ｐ＞ ０．０５）,在３ ｈ显著低于Ⅰ组（ Ｐ＜ ０．０１）,在５ 和７ ｈ 高于Ⅰ组（ Ｐ＜ ０．０５, Ｐ＜ ０．０１）,在９ ｈ,１２ ｈ 虽高于Ⅰ组但无显著差异（ Ｐ＞ ０．０５）。结果显示, Ｅ Ｔ 可使 Ｅ Ｃ Ｍ 荧光偏振度（ Ｐ）、微粘度（η）和脂双层分子排列有序性（ Ａ）增加。膜流动性降低,而６５４２ 能有效地改善 Ｅ Ｔ诱导的这些损伤变化,支持了６５４２ 具有维护膜结构和功能的生理作用的理论。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
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   

14.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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