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1.
以家蚕卵作为放射线生物影响研究的材料,用氦离子射线4He2+(12.5 Me V/u,水中射程1.5 mm)、碳离子射线12C5+(18.3 Me V/u,水中射程1.1 mm)和氖离子射线20Ne8+(17.5 Me V/u,水中射程0.6 mm)对供试蚕卵进行整体照射或局部照射,考察重离子射线对家蚕胚胎发育的影响。以照射后的孵化率为指标,调查发现家蚕胚胎对重离子辐射的敏感性随照射剂量的增加而增大;不同发育时期胚胎对重离子射线的辐射敏感性为早期胚胎的敏感性大于后期胚胎,以产卵后3 d内的胚胎对辐射的敏感性最高,产卵4 d以后胚胎的敏感性急速下降;家蚕胚胎对不同种类重离子射线的辐射敏感性不同,对射程长的4He2+和12C5+的辐射敏感性高于射程短的20Ne8+;蚕卵的受精核部位较非受精核部位对重离子射线的敏感性强。研究结果表明:不同发育阶段的家蚕胚胎对重离子射线的辐射敏感性、同一发育时期的胚胎对不同种类重离子射线的辐射敏感性以及蚕卵的受精核部位与非受精核部位对重离子射线的辐射敏感性均存在差异。 相似文献
2.
60Coγ射线辐照野牛草干种子的细胞学效应 总被引：1，自引：0，他引：1
通过5种不同剂量的60Coγ射线对野牛草(Buchloe dactyloides(Nutt) Engelm.)种子的辐射诱变效应研究表明,γ射线辐照能抑制野牛草根尖细胞的有丝分裂.随γ射线辐射剂量的增加,根尖细胞有丝分裂指数呈下降趋势.γ射线辐照能诱发根尖细胞的染色体畸变和核畸变,产生桥、染色体断片、粘连染色体、游离染色体、落后染色体、单微核、双微核、多微核、小核等多种畸变类型.在0～2000 Gy 范围内,随剂量的增加各种畸变率不断提高,至2000Gy 辐照剂量时,各畸变率达到最大. 相似文献
3.
重离子射线对家蚕幼虫造血功能的影响 总被引：4，自引：1，他引：3
用碳离子和氦离子射线照射家蚕 5龄蜕皮后 72h(5 3d)幼虫造血器官 ,体内和体外同时调查了造血器官形态结构和造血功能的变化。离子射线照射后家蚕造血器官很快开始解离 ,解离速度随照射剂量的增加而加快。体外 2 5℃悬滴培养 ,离子射线照射后的造血器官先失去血球分泌功能 ,然后造血器官萎缩解离 ,其变化速度也随射线剂量增大而加快。家蚕翅原基比造血器官对重离子射线的抵抗力强 ,用翅原基的存活状态可以检验离子射线对造血器官的损害程度。 相似文献
4.
空间飞行和60Co-γ射线辐照对苦荬菜种子的细胞学效应研究 总被引：4，自引：0，他引：4
利用返回式卫星搭载苦荬菜(Lactuca indica)干种子,研究比较其与用不同剂量γ射线辐照对苦荬菜根尖细胞的遗传学效应。实验结果表明:与地面对照组相比,种子空间飞行可促进根尖细胞有丝分裂;而γ射线则抑制根尖细胞有丝分裂,并随着辐照剂量的增加有丝分裂指数逐步下降。二者均可诱发根尖细胞产生微核、染色体断裂、染色体粘连、落后染色体、游离染色体、桥等畸变。但空间飞行诱发畸变的频率明显低于γ射线辐照。在γ射线辐照剂量0～30Gy范围内,随着剂量的增加,单微核、多微核和染色体总畸变频率逐步升高。 相似文献
5.
高能混合粒子场处理种子对龙牧803苜蓿M2代的抗寒性影响 总被引：2，自引：0，他引：2
利用高能粒子处理紫花苜蓿干种子,观测龙牧803苜蓿M2代在秋末冬初低温条件下叶片游离脯氨酸含量(Pro)、过氧化物歧化酶活性(SOD)、可溶性糖含量(LSSC)、叶绿素a含量(Chla)和叶绿素b含量(Chlb)。结果表明, 高能粒子处理在秋末冬初低温条件下M2代的抗寒性指标显著高于对照(P<0.05);随着辐照剂量的增大,M2代叶片Pro含量、SOD酶活性、LSSC含量、Chl含量明显递减。低剂量辐照下M2代获得的抗寒性强于高剂量辐照,由此确定苜蓿的最佳高能粒子辐照剂量为145 Gy,其次是195 Gy。 相似文献
6.
重金属铅暴露对家蚕组织GSTs和GSH-Px酶活力及基因表达的影响 总被引：1，自引：0，他引：1
谷胱甘肽S-转移酶(GST)和谷胱甘肽过氧化物酶(GSH-Px)是生物体内重要的解毒酶。为了研究重金属铅对鳞翅目昆虫的影响机制,给家蚕添食Pb(NO3)2进行Pb2+暴露,用酶活测定和real-time PCR方法,调查家蚕5龄6 d幼虫不同组织中酶活性及相关基因mRNA转录水平的变化。正常家蚕5龄6 d幼虫生殖腺中的GST酶活性分别是脂肪体和中肠中的20.0倍、34.6倍,GSH-Px酶活性分别是脂肪体和中肠中的57.7倍、46.6倍。幼虫食下含10 mg/kg Pb2+以上的人工饲料时,生殖腺中2种解毒酶的活性成倍下降;人工饲料含20～80 mg/kg Pb2+时,生殖腺中的Gstd1和Gsh-Px基因mRNA转录水平也显著下调,且雄性比雌性更加显著。幼虫食下含10～160 mg/kg Pb2+的人工饲料时,脂肪体中2种解毒酶活性显著升高,Pb2+对2种酶的影响浓度分别为10～160 mg/kg和20～80 mg/kg,但在20～80 mg/kg Pb2+范围内,Gsh-Px和Gstd1基因mRNA的转录却受到抑制,并且雌性幼虫脂肪体中的GSH-Px酶活性及其基因mRNA转录水平、雄性幼虫脂肪体中的GST酶活性及基因mRNA转录水平对Pb2+暴露更加敏感。幼虫食下含20 mg/kg Pb2+以上的人工饲料时,中肠的GST酶活性显著上升,而GSH-Px酶活性变化较小,性别间差异不明显;Gstd1基因mRNA转录水平有上调趋势,Gsh-Px基因mRNA转录水平则受到显著抑制。结果显示,家蚕幼虫生殖腺虽然有比脂肪体和中肠更强的GST酶和GSH-Px酶活性,但对Pb2+的毒害敏感,雄性比雌性受影响更大,生殖腺通过抗氧化防御系统抵御Pb2+毒害的作用很弱。 相似文献
7.
vasa是决定生殖系发育的重要调控蛋白因子之一,具有广泛的保守性。利用家蚕基因组和EST库的数据资源,分析了家蚕vasa基因的结构,并与已有报道的18个物种的VASA蛋白质的结构域序列进行了比对分析,同时对家蚕vasa基因在家蚕胚胎发育11个时期的表达型及幼虫期8个不同组织的表达特异性进行了验证。结果表明,家蚕vasa基因包含有13个外显子,比果蝇vasa基因的外显子数量(7个)增加了6个,在第3内含子有1个转座子插入;家蚕vasa基因在未受精卵和胚胎发育的各个时期均有表达,但只在幼虫生殖腺中有表达。将家蚕vasa基因的一条cDNA片段用地高辛标记作为探针,对家蚕幼虫的生殖腺及胚胎进行全胚原位杂交,结果进一步表明家蚕vasa基因在幼虫期只在精原细胞、精囊、卵巢管等生殖系相关的细胞和组织中表达,在发育5d胚胎的生殖腺部位也有明显表达。 相似文献
8.
为了验证高能混合粒子场作为诱变源应用在紫花苜蓿品种改良上的效果和价值,试验将5 000粒龙牧803紫花苜蓿干种子平均分为两份,一份用5个剂量(109,145,195,284,560 Gy)的高能混合粒子场辐照处理,另一份用与高能粒子场相同剂量的60Coγ射线辐照处理作为对照,通过发芽试验和RAPD分子标记对2种诱变源在紫花苜蓿上的作用效果进行比较。结果表明:使用高能混合粒子场处理紫花苜蓿对苜蓿种子的损伤较小,与传统60Coγ射线造成的损伤效果有明显区别,说明高能混合粒子场有作为新的诱变源应用的价值。 相似文献
9.
10.
为探明60Co-γ射线辐照对不同火龙果品种种子的辐射效应,以经60Co-γ射线辐照处理的7个火龙果品种新鲜种子为试验材料,研究不同辐照剂量(0、25、50、100、200、300、400、500Gy)对火龙果不同品种种子萌发以及出苗的辐射效应。结果表明,不同剂量60Co-γ射线辐照对火龙果种子的萌发和生长均有不同程度的影响,辐照剂量为25～100Gy时60Co-γ射线能促进种子萌发和生长,当剂量增大时,辐照对种子萌发率、出苗率和根的生长都表现出较强的抑制效应。100Gy时火龙果种子的萌发率和出苗率最高,200Gy～500Gy时火龙果种子萌芽生长受抑制,200Gy的出苗率均明显比对照低,并与对照存在极显著差异;100Gy是火龙果诱变育种适宜的辐照剂量。 相似文献
11.
Akio SUZUKI Kazuhei SAWADA Temuulen ERDENEBAT Takeshi YAMASAKI Minoru TOBIUME Kinuyo SUGA Motohiro HORIUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1735
There has been no report on Chronic wasting disease (CWD) cases in Japan to date; however, there is concern about the geographic spread of CWD. To clarify the CWD status in Japan, we conducted CWD monitoring using real-time quaking-induced conversion (RT-QuIC) assay which can detect the low level of CWD prions. A total of 690 obex samples collected from sika deer and Reeves’s muntjac in Hokkaido and Honshu was tested for CWD prions. No CWD-positive cases were found, suggesting that CWD is nonexistent in Japan. Our results also indicate that RT-QuIC assay is useful for continuous monitoring of CWD. Furthermore, nucleotide sequence analysis of the PrP gene revealed sika deer in Japan harbor CWD susceptible allele. 相似文献
12.
W.J. Hartley M.R.C.V.S. 《New Zealand veterinary journal》2013,61(4):111-117
Extract Sir,—Recently, when in Japan at W.H.O./F.A.O. Seminar on Zoonoses, I had skills with English-speaking veterinarians of South-East Asia and Western Pacific, particularly those of Japan, whose representation was higher, as was their information. 相似文献
13.
SUMMARY Bovine ephemeral fever (BEF) outbreaks were investigated in South Korea and Japan from 1953 to 1991, retrospectively. The epidemics occurred contemporaneously several times; particularly, those of 1988 and 1991. The initial outbreaks in the Fukuoka Prefecture, Japan, in 1988 and 1991 occurred about 1 month after those in Korea. Meteorological analysis showed that a low-level jet stream through Jeonnam Province in Korea struck the Fukuoka Prefecture of Japan during the epidemic. The BEF epidemics of Fukuoka Prefecture may have originated from infected vectors carried on the low-level jet stream. 相似文献
14.
Erina Fujiwara-Nagata Céline Chantry-Darmon Jean-Fran?ois Bernardet Mitsuru Eguchi Eric Duchaud Pierre Nicolas 《Veterinary research》2013,44(1):34
The bacterium Flavobacterium psychrophilum is a serious problem for salmonid farming worldwide. This study investigates by multilocus sequence typing (MLST) the population structure of this pathogen in Japan where it is also a major concern for ayu, a popular game fish related to salmoniforms. A total of 34 isolates collected across the country and 80 isolates sampled in a single model river by electrofishing were genotyped. The data accounting for 15 fish species allowed identifying 35 distinct sequence types (ST) in Japan. These ST are distinct from those reported elsewhere, except for some ST found in rainbow trout and coho salmon, two fish that have been the subject of intensive international trade. The pattern of polymorphism is, however, strikingly similar across geographical scales (model river, Japan, world) in terms of the fraction of molecular variance linked to the fish host (~50%) and of pairwise nucleotide diversity between ST (~5 Kbp-1). These observations go against the hypothesis of a recent introduction of F. psychrophilum in Japan. Two findings were made that are important for disease control: 1) at least two independent F. psychrophilum lineages infect ayu and 2) co-infections of the same individual fish by different strains occur. 相似文献
15.
Nanako YAMASHITA-KAWANISHI Chia Yu CHANG James K CHAMBERS Kazuyuki UCHIDA Katsuaki SUGIURA Iwao KUKIMOTO Hui Wen CHANG Takeshi HAGA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1229
Felis catus papillomavirus (FcaPV), especially type 2 (FcaPV2) is considered as one of the causative agents in squamous cell carcinoma (SCC) in cats. However, our previous study detected FcaPV3 and FcaPV4, but not FcaPV2 in feline SCCs collected in Japan, suggesting that the prevalence of FcaPV2 in SCC may vary depending on geographic locations. To evaluate this hypothesis, two conventional PCR reactions targeting E1 and E7 genes were performed to detect FcaPV2 in feline SCC samples collected in Taiwan and Japan. While 46.9% (23/49) of feline SCC cases from Taiwan were PCR positive for FcaPV2, only 8.6% (3/35) cases from Japan were positive. Our result suggests that the prevalence of FcaPV2 in feline SCCs may depend on the region. 相似文献
16.
Koichi Hagiya 《Animal Science Journal》2019,90(4):457-461
The procedure used for the genetic evaluation of dairy cattle in Japan has developed from a lactation sire–MGS model to a multiple‐lactation random regression test‐day animal model. Genetic evaluation of Holstein bulls in Japan began in 1989 with the use of field‐style progeny testing; dairy herd improvement program data from all over Japan were used, along with a sire and maternal grandsire model. In 1993, an animal model was introduced to estimate breeding values for yield and type traits. A random regression test‐day model was first applied in 2010. In the business of breeding dairy cattle, it is very important to users that estimated breeding values are reliable and stable among subsequent routine evaluations. With experience in the genetic evaluation of dairy cattle in Japan, Japanese researchers have found ways to improve the stability of estimated breeding values. These modifications involve changes in data editing, development of evaluation models, changes to the structures of unknown‐parent groups, awareness of the problems of predicting lactation yield from partial test‐day records, and adjustment for heterogeneity within herd variances. Here, I introduce developments in, and our experiences with, the genetic evaluation of yield traits of Holstein cattle in Japan. 相似文献
17.
Koiwai M Hamaoka T Haritani M Shimizu S Zeniya Y Eto M Yokoyama R Tsutsui T Kimura K Yamane I 《Veterinary parasitology》2006,135(2):175-179
Serum samples from 2420 clinically healthy dairy cattle, randomly selected from stored sera in 18 districts of Japan, were tested for the presence of Neospora caninum antibodies using an indirect fluorescent antibody test (titer > or =1:200). Nationwide seroprevalence is estimated at 5.7% (139/2420). Seropositive cattle were detected in all surveyed districts despite the evidence of confirmed case reports of bovine neosporosis, showing that N. caninum is widely distributed throughout Japan. Age-specific seroprevalence did not increase with cattle age, suggesting that Neospora infection is likely to be transmitted vertically rather than horizontally in Japan. Considering that N. caninum seropositive cows are thought to be more likely to abort, substantial fetal losses may be induced by N. caninum infection in Japan. Devising strategies are needed to reduce the economic impact on the Japanese dairy industry. This is the first study to investigate the nationwide seroprevalence of N. caninum in cattle in Asia. 相似文献
18.
Sasaki Y Tsujiyama Y Tanaka H Yoshida S Goshima T Oshima K Katayama S Yamada Y 《Zoonoses and public health》2011,58(5):350-356
The present study was conducted to estimate the prevalence of and to identify the risk factors for Campylobacter colonization in broiler flocks in Japan. Campylobacter colonization status in flock was evaluated by culturing pooled caecal excrement from 124 broiler flocks. Potential exposure to risk factors was evaluated with a questionnaire for the broiler producers. Odds ratios (ORs) were calculated using a multivariable logistic regression analysis. The prevalence of Campylobacter-positive flocks was 43.5% (upper and lower limits of 95% confidence interval (CI(95%) ): 34.8, 52.3). Multivariable logistic regression model identified two variables as risk factors for Campylobacter colonization. The ORs of Campylobacter colonization were higher in flocks in western Japan (OR=2.68; CI(95%) : 1.04, 6.91) than in eastern Japan, and in flocks supplied with undisinfected drinking water (OR=7.41; CI(95%) : 3.11, 17.66) than in those supplied with disinfected drinking water. These findings indicate that water may play an important role in Campylobacter colonization in broiler flocks in Japan and the use of disinfected water may reduce the risk of Campylobacter colonization. 相似文献
19.
Mahmoud HY Suzuki K Tsuji T Yokoyama M Shimojima M Maeda K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(11):1535-1537
In Japan, most pig populations are now free from pseudorabies virus (PRV) due to the recent success of an extensive eradication program. However, PRV infection persists in Japanese wild boars (Sus scrofa leucomystax), representing another potential reservoir for the virus in Japan. In this study, the seroprevalence of PRV in wild boars captured in three different prefectures was ascertained. A virus neutralization (VN) test showed that 6 of 173 serum samples (3%) were positive for VN antibody; glycoprotein E-ELISA revealed infection with the wild-type, but not the available vaccine strain, PRV. These results indicate that PRV has continued to spread among wild boars in Japan. 相似文献
20.
Yuko TAJIMA Kyoko SASAKI Nobuyuki KASHIWAGI Tadasu K. YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):989-992
Lobomycosis is a chronic fungal disease caused by the etiologic agent, Lacazia loboi, in the skin and subcutaneous tissues in humans and dolphins in tropical and transitional tropical climates. An Indo-Pacific bottlenose dolphin (Tursiops aduncus) stranded in Kagoshima, Japan, had severe skin lesions characterized by granulomatous reactions and hyperkeratosis that were similar to those of the lobomycosis, but no fungal organism was observed in the skin lesion. In this paper, we report a stranded Indo-Pacific bottlenose dolphin with lobomycosis-like lesions based on pathological examinations in Japan. 相似文献