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51.
听力是日语学习的一个重要方面,影响学生听力的因素是多方面的。笔者主要从词汇量的积累、背景知识的掌握、泛读与精读相结合及如何克服不良心理因素,培养综合处理听力等几方面论述了提高大学生日语听力能力的对策。 相似文献
52.
Allele frequencies of the extension locus encoding the melanocortin-1 receptor in Japanese and Korean cattle 总被引:2,自引:0,他引:2
Shinji SASAZAKI Munehiro USUI Hideyuki MANNEN Chihiro HIURA Soichi TSUJI 《Animal Science Journal》2005,76(2):129-132
In order to estimate the influence of the Extension (E) locus in cattle coat color, the melanocortin‐1 receptor (MC1R) gene in Japanese Black, Japanese Brown and Korean (Hanwoo) cattle were sequenced. The sequences of the coding region revealed three alleles (ED, E+ and e), which were previously reported. Polymerase chain reaction‐restriction fragment length polymorphism was performed to investigate the gene frequencies of the three breeds. Japanese Black was almost composed of ED and E+ individuals, ED = 0.481 and E+ = 0.514, and no homozygous e/e, therefore that is consistent with the hypothesis that ED and E+ induce black pigment synthesis. Allele frequencies between Japanese Brown and Hanwoo were obviously different; however, recessive red e allele frequency was 0.038 for Japanese Brown and 0.948 for Hanwoo, even though both breeds have quite similar coat colors (ranging from yellowish brown to dark brown including a red coat color). This result suggested that other genes are also associated with a coat color of red and brown in cattle. 相似文献
53.
Kentaro Okuno Tomoko Hama Minoru Takeshita Naruto Furuya Yoichi Takanami 《Journal of General Plant Pathology》2003,69(2):138-142
A potyvirus, for which the name Japanese hornwort mosaic virus (JHMV) is proposed, was isolated from Japanese hornwort plants
(Cryptotaenia japonica) with mosaic disease symptoms. The virus was used to inoculate mechanically 34 plants belonging to 33 species of 10 families.
Of these species seven from two families were infected. Faint chlorotic spots appeared on the inoculated leaves of Chenopodium quinoa and C. amaranticolor, but no systemic infection occurred in these plants. JHMV systemically infected only Umbelliferae plants; they did not infect
26 other species in eight families. JHMV was transmitted in a nonpersistent manner by aphids (Myzus persicae). The virus was a flexuous rod-shaped particle about 750 nm in length. Sequencing the nucleotides in the 3′ terminal region
of JHMV revealed that the coat protein contains 280 amino acids with a molecular mass of 32.2 kDa. The nucleotide sequence
of the coat protein of JHMV had the highest similarity with that of Zantedeschia mosaic virus (83.3%) compared to those of
other potyviruses (57.0%–64.9%). An antiserum against JHMV reacted strongly with JHMV and weakly with Potato virus Y. These results indicate that JHMV is a new potyvirus.
Received: September 9, 2002 / Accepted: November 7, 2002
RID="*"
ID="*" The nucleotide sequence determined in this work appears in the DDBJ/EMBL/GenBank nucleotide sequence databases with
the accession number AB081518 相似文献
54.
Masuda K Sakaguchi M Saito S Deboer DJ Yamashita K Hasegawa A Ohno K Tsujimoto H 《Veterinary dermatology》2002,13(1):55-61
Three dogs were examined because of episodes of recurrent pruritic dermatitis in the spring, the season of Japanese cedar (Cryptomeria japonica, CJ) pollination in Japan. The dogs were shown to be sensitive to CJ pollen allergen using intradermal testing and antigen-specific IgE measurement. Fluorometric enzyme-linked immunosorbant assay (ELISA) showed increased concentrations of IgE specific to Cry j 1 and a negative result for Cry j 2 in the three dogs. The concentrations of IgE specific to Cry j 1 during the season of CJ pollination were higher than the concentrations found during the off-season in all the dogs, and the variation in the concentrations correlated with the variation in clinical signs. Peripheral blood mononuclear cells showed apparent proliferative responses to crude CJ pollen antigen and Cry j 1 during CJ pollination season. These findings indicated that Cry j 1 was the major allergen recognized by IgE and lymphocytes and resulted in the development of type I hypersensitivity to CJ pollen allergen in these atopic dogs. 相似文献
55.
将微山湖野生日本鸣鹑与家鹌鹑杂交F2代按1公∶5母进行分组,采用秒表单位记时法观察鹌鹑的行为,并引用同期亲本和F1代的相同资料,对鸣叫、打斗和交配行为频次进行比较。结果表明:①杂交F2代鹌鹑鸣叫行为比家鹑低,除10∶00~11∶00外,其余时间段均存在显著差异(P<0.05);在14∶00~15∶00与野生日本鸣鹑存在显著差异(P<0.05);在14∶00~16∶00杂交F1代有显著差异(P<0.05);②杂交F2代鹌鹑打斗行为除16∶00~17∶00外与家鹑及杂交F1代无显著差异;③杂交F2代鹌鹑交配行为除16∶00~18∶00外与家鹑及杂交F1代均有显著差异(P<0.05)。 相似文献
56.
《The Journal of Applied Poultry Research》2006,15(3):442-446
Escherichia coli isolates were cultured from diseased Japanese quail and their environment. Of 31 E. coli isolates, 11 were cultured from heart blood of dead Japanese quail and 20 were from dead-in-shell embryos, fluff samples, and footbath and drinking water samples. All E. coli isolates were moderately positive on the Congo red binder test and 14 out of 31 isolates produced hemolysis on sheep blood agar. Twenty-seven isolates were grouped under serogroups O4, O9, O38, O42, and O88, whereas 4 isolates could not be typed. Of the E. coli isolates cultured from Japanese quail infected with colibacillosis, 54.5% belonged to serogroup O9 and the same serotype was predominant in the hatchery environment. All the E. coli isolates showed high resistance to multiple drugs with 100% resistance observed against ampicillin/cloxacillin, chloramphenicol, tetracycline, and cotrimoxazole. The highest sensitivity was observed against nitrofurantoin. This study shows that hatchery hygiene should be improved to control colibacillosis and reduce production losses. At the same time, indiscriminate use of antibiotics should be avoided as it increases the risk of development of drug-resistant strains of bacteria. 相似文献
57.
M. Nagai M. Sato H. Nagano H. Pang X. Kong T. Murakami T. Ozawa H. Akashi 《Veterinary microbiology》1998,60(2-4):271-276
Cytopathogenic and non-cytopathogenic bovine viral diarrhea viruses (BVDVs) were isolated from cattle with mucosal disease or persistent infection in Japan. These isolates were compared for antigenic properties by cross-neutralization tests with Japanese reference strains of BVDV belonging to classical type 1. Significantly low cross-reactivity to reference strains was noted, indicating the viruses to possibly represent a new serotype in Japan. Thus, to determine the genotype of the isolates, nucleotide sequences of the 5′ untranslated region were determined and compared with those of previously reported BVDV 1 and 2. The isolates were clearly shown to belong to BVDV 2, not to BVDV 1. 相似文献
58.
忽海燕 《山西农业大学学报(自然科学版)》1999,(1)
汉语中的“着”字,是一个常见的多音、多词性、多义的词,出现频率高,使用范围广,因此,把汉语“着”字译成日语时,也就出现了多种不同的译法。本文按照“着”字的汉语读音、词性、词义的顺序,通过实例就它的日译问题进行一番分析。 相似文献
59.
Japanese encephalitis B (JE) is a zoonosis caused by Japanese encephalitis virus which invades the central nervous system,infected by mosquito.Various animals could be the sower and reservoir of JE including swine,horse,cattle and avian.JE could cause a major public health trouble and a horrible crisis of the farm all in Asia and the Western Pacific region.Therefore,it is necessary to diagnose it rapidly and accurately.This review article made a sketch of approaches for the rapid serological assays of JE,including traditional method,emerging technologies and specific improvements of the assay,so as to provide references for the study of rapid,simple and accurate JE diagnose methods. 相似文献
60.
Differences in the behavior of the crossbred steers of different sire lines of Japanese Black cattle
Katsuji UETAKE Toshie ISHIWATA Robert J. KILGOUR Toshio TANAKA 《Animal Science Journal》2012,83(2):184-186
We determined differences in the behavior of the progeny of two major sire lines of Japanese Black cattle by recording the behavior of 35 and 70 half-sib steers of sires from fast (FG) and slow (SG) growing lines, respectively. Two sire lines of steers were mixed and allocated to nine pens with 11–12 animals per pen. The proportion of steers lying was significantly (P < 0.001) higher in the SG line (43.4 ± 5.7% compared to 40.3 ± 6.0%). The proportion of time spent eating concentrate feed (FG: 12.1 ± 2.3%; SG: 11.4 ± 2.1%), drinking (FG: 0.8 ± 1.1%; SG: 0.4 ± 0.6%), licking the feed trough (FG: 0.4 ± 0.6%; SG: 0.2 ± 0.4%) and performing tongue-playing (FG: 3.1 ± 4.6%; SG: 1.0 ± 1.9%) was significantly higher in FG, whereas the proportion of time spent resting (FG: 41.5 ± 12.8%; SG: 43.7 ± 10.9%) and performing self-licking (FG: 1.7 ± 1.4%; SG: 2.1 ± 1.3%) was higher in SG (all P < 0.05). These results show progeny of the FG sire engaged in more active behaviors compared to the progeny of the SG sire line. 相似文献