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21.
Cell numbers of known species of nitrate- and nitrite-reducing bacteria, Selenomonas ruminantium, Veillonella parvula and Wollinella succinogenes , in the rumen of goats (25–30 kg) were estimated by competitive polymerase chain reaction (PCR). The number of S. ruminantium was the largest of the three species examined, and tended to be greater in goats fed a high-concentrate diet (5.6 × 107 cells/mL rumen fluid) than in goats fed a high-roughage diet (1.3 × 107 cells/mL). The number of V. parvula tended to be greater when goats were fed a high-roughage diet (6.7 × 103 /mL) than when fed a high-concentrate diet (3.2 × 103 /mL). The number of W. succinogenes was below the detectable level (< 1.0 × 102 /mL) when a high-concentrate diet was fed, but was significantly increased by feeding a high-roughage diet (1.6 × 103 /mL). Addition of potassium nitrate (6 g/day) to the high-concentrate diet tended to increase V. parvula , and significantly increased W. succinogenes , indicating that these two bacteria can be increased by feeding a diet containing nitrate. 相似文献
22.
Summary A combination of compatible second pollinations and embryo rescue was applied for systematic production of true tetraploid hybrids from crosses between disomic tetraploid Solanum acaule and tetrasomic tetraploid potato, S. tuberosum. Several genotypes of tetraploid potatoes were pollinated with S. acaule, and the compatible second pollinations were made on the following day, with a genotype of S. phureja, IvP 35 to promote fruit development. Embryo rescue was carried out in 21 families, 14 to 27 days after the first pollination. A total of eight plants were obtained from the embryo rescue and their chromosome numbers were counted in the root tips. Three of the eight plants were identified as tetraploid, and five others as diploid. Morphology, isozyme banding patterns, and pollen stainability, as well as potato spindle tuber viroid (PSTVd) resistance, indicated the hybrid nature of the three plants. This is the first report of successful tetraploid hybrid production between disomic tetraploid S. acaule (4x) and tetrasomic tetraploid potatoes. Seed set from the crosses between one of hybrids and diploid potatoes indicated workable levels of both male and female fertility for introgression of valuable genes from S. acaule into the cultivated potato gene pool. The methodology used may be applied to other disomic tetraploid tuber-bearing Solanum species and with some modifications also to distantly related solanaceous species and genera. 相似文献
23.
Nihei K Ying BP Murakami T Matsuda H Hashimoto M Kubo I 《Journal of agricultural and food chemistry》2005,53(3):608-613
This is the first report for secondary metabolites in an African medicinal plant, Pachyelasma tessmannii (Leguminosae). Four novel saponins, pachyelasides A-D, were isolated from the methanol extract of the root bark by using recycling HPLC. These compounds showed molluscicidal activity (LD(50) < or =8.0 mug/mL) against the South American snail, Biomphalaria glabratus. The structures were determined on the basis of extensive nuclear magnetic resonance spectroscopic and matrix-assisted laser desorption/ionization time-of-flight mass spectrometric studies. 相似文献
24.
Soma A Onodera A Sugahara J Kanai A Yachie N Tomita M Kawamura F Sekine Y 《Science (New York, N.Y.)》2007,318(5849):450-453
A computational analysis of the nuclear genome of a red alga, Cyanidioschyzon merolae, identified 11 transfer RNA (tRNA) genes in which the 3' half of the tRNA lies upstream of the 5' half in the genome. We verified that these genes are expressed and produce mature tRNAs that are aminoacylated. Analysis of tRNA-processing intermediates for these genes indicates an unusual processing pathway in which the termini of the tRNA precursor are ligated, resulting in formation of a characteristic circular RNA intermediate that is then processed at the acceptor stem to generate the correct termini. 相似文献
25.
Hu F Furihata K Ito-Ishida M Kaminogawa S Tanokura M 《Journal of agricultural and food chemistry》2004,52(16):4969-4974
In this study were successfully observed the one- (1H, 13C) and two-dimensional (1H-13C, 1H-15N, 1H-31P) NMR spectra of milk directly without any pretreatment. The signals of each NMR spectrum were assigned, and their existing states were also analyzed. Lactose existed in a free state in milk. The signals due to the butyric acid chain can be assigned among the other fatty acid chains. Monounsaturated fatty acid (oleic acid chains) and polyunsaturated fatty acid chains (linoleic and linolenic acid) were assigned by their characteristic signals. The signals from citrate, N-acetylcarbohydrates, and lecithin could be observed directly in the 1H-13C HSQC NMR spectra; the assignment of their signals was made through the 1H-13C, 1H-15N, and 1H-31P HMBC spectra of extracted milk. Signals from creatine and N-acetylcarbohydrates were detected for the first time. 相似文献
26.
Hiroshi FUJISE Masaru MURAKAMI Bhuminand DEVKOTA Ishwori Prasad DHAKAL Kumiko TAKEDA Hirofumi HANADA Hideo FUJITANI Masao SASAKI Kosaku KOBAYASHI 《Animal Science Journal》2003,74(1):1-5
Lulu is a dwarf cattle population bred in the Mustang district of western and central Nepal. This area is located around the habitat boundary between Bos taurus and Bos indicus. The peculiarities of Lulu are their small size (weight range in the adult female: 68–153 kg) and rearing in high mountain areas at 2800 m to 4000 m in altitude. There were 5770 head of Lulu cattle in the Mustang district in 1998, 4333 females and 1437 males. The morphological appearance of Lulu is Bos taurus. However, one of the five Lulu studied in Kagbeni, Mustang had a Bos indicus mitochondrial DNA type based on the D‐loop sequence, while the other four were Bos taurus. It is suggested that there are hybrids of Lulu with Bos indicus maternal lineage in a mostly taurine‐breed genetic background. Steps must be taken to preserve the unique Lulu. 相似文献
27.
A Matsuda Tsuchida S Katayama N Okada T Okabe N Sasaki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(3):447-452
The antigens gII, gIII and gVI were purified from the lysates of the pseudorabies virus (PRV) -infected HmLu-1 cells using Sepharose 4 B coupled with MAbs against these antigens. Mice immunized with either gII, gIII, gVI antigen or a mixture of them were challenged intraperitoneally with 8.5 x 10(3) plaque forming units of PRV. All the mice immunized with 1.5 and 4.5 micrograms of the mixture and 4.5 micrograms of the gIII antigen survived. The sera of mice immunized with the mixture had virus neutralizing activity which was independent of complement, hemagglutination inhibition activity, and recognized major (93 kilodaltons) and minor (129, 74, 68 and 50 kilodaltons) PRV proteins under reducing conditions in western blotting. The serological activity levels in the lower survival group were not different from those in the complete survival. These results indicate that the mixture of each glycoprotein is more effective for eliciting of protective immunities in mice and that serological activity do not always correlate with protection. 相似文献
28.
Morifusa Eto Sachiko Okabe Yoshihisa Ozoe Kazuyuki Maekawa 《Pesticide biochemistry and physiology》1977,7(4):367-377
O,S-Dimethyl phosphoramidothiolate, the insecticide methamidophos, is converted oxidatively into a potent anti-cholinesterase agent by the action of m-chloroperbenzoic acid. The active intermediate is not stable enough to be isolated. From some chemical evidence, the sulfoxide, i.e., dimethyl phosphoramidothiolate S-oxide, is most probably the active intermediate. A similar activation may occur by biological oxidation. 相似文献
29.
Miyama T Sakata Y Shimada Y Ogino S Watanabe M Itamoto K Okuda M Verdida RA Xuan X Nagasawa H Inokuma H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(5):467-471
To determine the distribution of Babesia gibsoni infection in dogs in the eastern part of Japan, an epidemiological survey of dogs suspected of having B. gibsoni infection was attempted using the polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Thirty-five of 115 such dogs (30.4%) were positive by PCR and/or ELISA. The 35 positive dogs consisted of 28 Tosa dogs, 4 American Pit Bull Terriers, and 3 mongrel dogs in Aomori, Fukushima, Ibaraki, Gunma, Chiba, Tokyo, Kanagawa, and Nagano Prefectures. The positive dogs had a significantly lower rate of tick exposure and a higher rate of bites by other dogs. Twenty-two of 35 B. gibsoni-positive dogs were infected with hemoplasma, and the rate of infection was significantly higher than that of B. gibsoni-negative dogs. 相似文献
30.
Inokuma H Yoshizaki Y Matsumoto K Okuda M Onishi T Nakagome K Kosugi R Hirakawa M 《Veterinary parasitology》2004,121(3-4):341-346
A total of 80 free-roaming dogs on Okinawa Island, Japan, were examined for Babesia infection using the polymerase chain reaction (PCR) and sequence analysis. Of 80 samples, 12 were positive in a Babesia genus-specific PCR. Consequent species-specific PCR for B. canis and B. gibsoni revealed that 5 (6.3%) and 7 (8.8%) dogs were infected with B. canis and B. gibsoni, respectively. Sequence analysis of the PCR products revealed that the 18S rRNA gene sequence of B. canis detected from dogs in Okinawa was very close to B. canis vogeli with sequence similarity of 99.94%. 相似文献