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91.
We investigated the effects of integrated organic and inorganic fertilizers on the growth and yield of indica rice variety Manawthukha and japonica rice variety Genkitsukushi. In a split-plot design, the two rice varieties were assigned as main plot factors, and the integrated treatments were the subplot factors, including no-N fertilizer(N_0), 50% chemical fertilizer(CF)(CF_(50)), 100% CF(CF100), 50% CF + 50% poultry manure(PM)(CF_(50)PM_(50)), 50% CF + 50% cow manure(CM)(CF_(50)CM_(50)), and 50% CF + 50% compost(CP)(CF_(50)CP_(50)). CF100 was equivalent to N at 85 kg/hm~2. Manure was applied based on the estimated mineralizable nitrogen(EMN) level, which is dependent on total N(%) of each manure type. Manawthukha rice plants were taller with higher tiller number and dry matter content. However, higher soil-plant analysis development(SPAD) values were measured in Genkitsukushi throughout the crop growth period, resulting in higher seed-setting rate(%) and greater yield. At the same N level, CF_(50)PM_(50) application in both rice varieties resulted in higher SPAD values, plant height and tiller number than CF_(100). CF_(50)PM_(50) containing total N more than 4% supplied synchronized N for the demands of the rice plants, resulting in maximum dry matter, yield and yield components. CF_(50)CM_(50) and CF_(50)CP_(50) treatments containing total N less than 4% resulted in lower yields which were similar to CF_(100). These results indicated that integrating organic and inorganic fertilizers enhanced growth parameters and yields of Manawthukha and Genkitsukushi, while reducing the dose of chemical fertilizer.  相似文献   
92.
In ultrasonographic diagnosis of ovarian disorders and the estrous cycle in sows, transverse observation of the uterus yielded more characteristic findings than observation of sagittal sections. Transverse ultrasonography revealed that the low progesterone (P) type uterus showed a round structure, while the high P type uterus showed a flattened structure. These results corresponded well with rectal palpation findings: the low P type uterus had a hard, pipe-like structure and the high P type a soft, balloon-like structure. For gilts, we employed a minimum convex type transrectal prostate probe that had an approximately 18 cm insertion handle. The images of the uterus obtained thereby were a similar to those obtained from sows. The above results suggest that it should be possible to diagnose and treat many ovarian disorders in sows and gilts based only on the ultrasonograhic findings. In short, ultrasonograhic findings of a round structure of the uterine wall might be an indication for PMSG (pregnant mare serum gonadotropin) treatment, while findings of a flattened structure might be an indication for PGF(2) (alpha) administration.  相似文献   
93.
Phylogenetic tree and partial nucleotide sequence analysis of RNA segment 3 were conducted to compare the Ibaraki virus (IBAV) strains from three epidemics in Japan, and serotype 2 epizootic hemorrhagic disease virus strains isolated in Australia, Taiwan, and Canada. Each strain was classified relative to the Ibaraki disease (IBAD) epidemics, which occurred in 1959-1960, 1987, or 1997-1998. In particular, major variation of the gene was identified in the strains isolated after 1997 when a new type of IBAD with the abnormal birth was confirmed. Ibaraki viruses isolated in Japan were more closely related to Taiwanese and Australian strains based on genetics, while the Canadian strain was more distantly related.  相似文献   
94.
cDNA cloning and expressions of cytochrome P450 1A in zebrafish embryos   总被引:4,自引:0,他引:4  
Cytochrome P450 1A (CYP1A) is well known for being induced by aromatic hydrocarbons, including 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD). We determined the complete cDNA sequence of a CYP1A open reading frame with both 5'- and 3'-ends in zebrafish (zfCYP1A), a useful model for environmental toxicology. zfCYP1A shows high percentage identity with CYP1As of mammals, domestic fowl and xenopus (51.9-60.4%), as well as the other fish species (63.8-89.2%). As revealed by in situ hybridization and immunohistochemistry, zfCYP1A was scarcely detected in control embryos but was markedly induced by TCDD especially in heart, vascular endothelial cells, intestinal epithelium, pronephros and outer integument in both prehatched and hatched embryos. These expression patterns are consistent with possible involvement of zfCYP1A in TCDD-induced toxicities.  相似文献   
95.
A 5-month-old male Great Pyrenees with symptoms of convulsions, circling, and a head tilt was referred to the Animal Medical Center of Nihon University. On a magnetic resonance image (MRI), a cyst in the posterior fossa was noted and a part of the cyst enhanced by gadoteridol. Based on MRI and clinical findings, the patient was tentatively diagnosed with a cyst formation tumor, and an operation to open the cyst and remove the part enhanced by contrast was performed. Postoperatively, the clinical course was good. Pathologically, the removed tissue was diagnosed as a gliosis with cyst formation.  相似文献   
96.
Many organophosphorus (OP) compounds are of the thiono form and in insects or animals are converted by microsomal mixed function oxidases (MFO) into the oxon forms which inhibit acetylcholinesterase (AChE) and give toxic activity. However, certain S-alkyl phosphorothiolates (RS-P(O) <) such as methamidophos, profenophos and prothiophos oxon are strongly insecticidal, but very poor inhibitors of AChE in vitro. Their oxons are converted further to the S-oxides, which either inhibit AChE or decompose, depending on the alkyl substituents on the sulfur atom. It is also inferred in the case of prothiophos oxon that its S-oxide not only inhibits AChE but also conjugates with glutathione (GSH) by the action of glutathione S-transferase (GST), and the conjugate inhibits AChE. Certain phosphoramidates (R2N-P(O) <) such as isofenphos oxon, schradan and propetamphos oxon are weak AChE inhibitors, but strongly insecticidal. It is well known that isofenphos oxon is converted into the stable N-desalkyl form (H2N-P(O) <) by oxidative dealkylation to inhibit AChE. The authors have studied activation of phosphoramidates using 2,4-dichlorophenyl methyl N-alkylphosphoramidates as model compounds using various approaches including computational chemistry, and these studies indicated that the O-aminophosphate structure (R2N-O-P(O) <) is an activated form.  相似文献   
97.
Gonadal germ cells (GGC) were collected from the gonads of 7‐ or 9‐day‐old White Leghorn chick embryos and suspended in freezing medium containing 10% dimethylsulfoxide (DMSO). The cell suspension was frozen at ?1°C/min. until the temperature reached ?80°C. Then, the cells were immersed in liquid nitrogen at ?196°C and stored for 3–4 months. Approximately 50 frozen/thawed GGC were injected into the dorsal aorta of each 2‐day‐old Rhode Island Red (RIR) embryo, from which blood was drawn before germ‐cell injection. The injected embryos were incubated until they hatched and the chicks were raised until sexually mature. On reaching sexual maturity, a progeny test was performed by mating recipient chicks with normal RIR of the opposite sex. Progenies were obtained from male germ cell recipients that were injected with germ cells collected from 7‐ and 9‐day‐old embryos. The results demonstrated that frozen/thawed GGC collected from 7‐ or 9‐day‐old fertilized eggs can be used to produce male germ‐line chimeras.  相似文献   
98.
A 10-year-old female mongrel cat with back pain was brought to the Nihon University Animal Medical Center. Palpation demonstrated a mass in the back region. Radiography revealed partial destruction of the processus spinosus and the arch of the T8 and T9 vertebrae. On magnetic resonance imaging, the mass was found to have compressed the spinal cord and extended to the outside of the spinal canal. We performed extirpation of the mass, and confirmed that it arose from the spinal canal. Histopathologically, the mass was a malignant peripheral nerve sheath tumor.  相似文献   
99.
Smut disease of sugarcane causes considerable yield losses and the use of resistant varieties is the best control practice. Our group identified a Japanese wild sugarcane with highly smut disease resistance named ‘Iriomote8’. In this study, we conducted QTL analysis for smut disease resistance using a mapping population derived from a resistant variety ‘Yaenoushie’, in which resistance is inherited from ‘Iriomote8’. We identified 4813 non-redundant markers using GRAS-Di technology and developed a linkage map of mapping parents. We evaluated smut disease resistance of the mapping population by the inoculation test. Consequently, a large number of clones did not show the disease symptoms and the distribution of smut disease incidence tended to be “L shaped”. Composite interval mapping detected an identical QTL for indices of smut disease incidence with a markedly high LOD score (26.6~45.6) at the end of linkage group 8 of ‘Yaenoushie’. This QTL explained approximately 50% of the cases of smut disease incidence. In the mapping population, there were no correlations between the indices of smut disease incidence and other agronomic traits. In conclusion, this QTL could be used for marker-assisted selection to significantly improve smut disease resistance without negative effects on other agronomic traits.  相似文献   
100.
茶挥发性成分中的萜烯醇类具有生物合成的遗传特性。根据萜烯指数(即:芳樟醇及其氧化物/(芳樟醇及其氧化物十香叶醇)比值,TI〕所作的化学分类表明,云南省茶的 TI 值接近于1.0,而分布于其他产茶省区的茶树 TI 值均低于上述值,并伴随有由西南向东和东南逐渐下降的趋势。由云南引入的日本山茶,具有与云南相近的 TI 值,而日本当地茶树品种的 TI 值与中国浙江相近似,因而推测中国茶树的原产地为云南,然后沿长江和沿海逐渐向东和南方传播。  相似文献   
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