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排序方式: 共有312条查询结果,搜索用时 13 毫秒
111.
Suzuki A Urushitani H Watanabe H Sato T Iguchi T Kobayashi T Ohta Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(7):725-731
Female reproductive organs are mainly regulated by estrogen and progesterone. Specifically, the uterus, vagina and mammary gland show organ-specific mitosis and morphological changes during proliferative events, such as estrous cycle, gestation and lactation. The mechanism underlying these organ-specific estrogen-dependent events is still unknown. We examined, therefore, global gene expression in the mature uterus, vagina and mammary gland of ovariectomized adult mice 6 hr after an injection of 5 microg/kg 17beta-estradiol (E2) using a microarray method in order to identify primary E2-responsive genes. Half of the E2 up-regulated genes in the uterus were similar to those in the vagina. E2 up-regulated the expression of Insulin-like growth factor 1 (Igf-1) genes in the uterus and vagina. In the vagina, E2 up-regulated the expression of IGF binding proteins (Igfbp2 and Igfbp5). In the mammary gland, unlike the uterus and vagina, no gene showed altered expression 6 hr after the E2 exposure. These results suggest that expression of Igf-1 and morphogenesis genes is regulated by E2 in an organ-specific manner, and it is supported by the results of BrdU labeling showing E2-induced mitosis in the uterus and vagina except the mammary gland. The differences in organ specificity in response to E2 may be attributed by differences in gene expression regulated by E2 in female reproductive organs. The candidate estrogen-responsive genes in the uterus and vagina identified by profiling provide an important foundation understanding functional mechanisms of estrogen regulating morphogenesis and maintenance of each reproductive organ. 相似文献
112.
Khoirun Nisa Sue Yee Lim Masayoshi Shinohara Tatsuyuki Osuga Nozomu Yokoyama Masahiro Tamura Noriyuki Nagata Kazuyoshi Sasaoka Angkhana Dermlim Rommaneeya Leela‐Arporn Tomoya Morita Noboru Sasaki Keitaro Morishita Kensuke Nakamura Hiroshi Ohta Mitsuyoshi Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(2):559-568
113.
On Shimokamagari, an island of the Seto Island Sea, patterns of vegetation in the landscape were studied using vegetation
maps. Relationships between social and economic changes, site conditions and the vegetation were examined from a historical
perspective. In the process of economic development, mandarin orange production became important on this island. However,
over-production, a reduction in the price of mandarin oranges and low-temperature damage to orange trees caused large citrus
orchards to be abandoned. A plant community dominated by kudzu appeared in the abandoned orchards and the pine forests, as
well. These changes in orchards were connected with the natural site conditions, such as soil, geology, inclination, elevation,
direction of slope, and also with artificial conditions, such as density of working paths. Another factor causing change was
the replacement of the organic fertilizer of litter from forests by chemical fertilizer since the 1960's. As a result, medium
and small forests of pine became tall forests and tall forests of pine changed into tall oak forests. In the human-dominated
areas, the major factors affecting the process of vegetation were economic activities, and after the abandonment of the farm-lands,
forest succession were controlled by natural site conditions.
This paper was presented at the World-Congress of Landscape Ecology in Ottawa, 1991
Titles are tentative translations for original titles in Japanese by the authors. 相似文献
114.
Nakamura K Sasaki N Murakami M Bandula Kumara WR Ohta H Yamasaki M Takagi S Osaki T Takiguchi M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(6):1290-1297
Background: Contrast‐enhanced ultrasonography with perflubutane microbubbles improves the diagnostic accuracy to differentiate benign and malignant focal liver lesions in dogs. Hypothesis: Perflubutane microbubbles‐enhanced ultrasonography is useful for differentiation of benign from malignant focal splenic lesions in dogs. Animals: Twenty‐nine clinical dogs with single or multiple focal splenic lesions detected by conventional ultrasonography. Methods: Prospective clinical observational study. Perflubutane microbubbles‐enhanced ultrasonography was performed in 29 dogs with focal splenic lesions. Qualitative assessment of the enhancement pattern was performed in the early vascular, late vascular, and parenchymal phases. Results: In the early vascular phase, a hypoechoic pattern was significantly associated with malignancy (P= .02) with sensitivity of 38% (95% confidence interval [CI], 25–38%) and specificity of 100% (95% CI, 84–100%). In the late vascular phase, a hypoechoic pattern was significantly associated with malignancy (P= .001) with sensitivity of 81% (95% CI, 66–90%) and specificity of 85% (95% CI, 65–95%). There was no significant difference between malignant and benign lesions during the parenchymal phase. Conclusions and Clinical Importance: Hypoechoic splenic nodules in the early and late vascular phases with perflubutane microbubbles‐enhanced ultrasonography are strongly suggestive of malignancy in dogs. 相似文献
115.
Uchiyama H Ohtani N Ohta M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(5):521-526
The aims of this study were to measure the activity of the autonomic nervous system using heart rate variability (HRV) during learning tasks and to clarify the relationship between learning to overcome a difficult situation and the autonomic nervous system in monkeys. Two young male monkeys (Macaca mulatta) were given simple discrimination learning tasks (DL) and delayed matching to samples tasks (DMTS); Holter-type electrocardiography was done, and HRV was measured. We defined the frequency bands of HRV in rhesus macaques; the low frequency (LF) was 0.01-0.15 Hz, and the high frequency (HF) was 0.15-0.50 Hz. Based on these frequency bands, the LF/HF ratios during learning tasks were analyzed, and a significant increase in the ratio was found during the tasks. The variances in the HF differed between the DL and DMTS tasks; during DMTS tasks, HF variances had a tendency to increase. Our results indicate that increased sympathetic activity accompanied learning and suggest that the parasympathetic nervous system plays a key role during learning, particularly when difficult tasks are being learned. 相似文献
116.
Oku K Ohta M Katoh T Moriyama H Kusano K Fujinaga T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(8):773-778
We examined the influence of propofol infusion on cardiovascular system at the rate of 0.14, 0.20 and 0.30 mg/kg/min in six adult Thoroughbred horses. The cardiovascular parameters were heart rate (HR), mean arterial pressure (MAP), mean right atrial pressure (MRAP), stroke volume (SV), cardiac output (CO), systemic vascular resistance (SVR), pre-ejection period (PEP) and ejection time (ET). In order to keep the ventilation conditions constantly, intermittent positive pressure ventilation was performed, and the partial arterial CO(2) pressure was maintained at 45 to 55 mmHg during maintenance anesthesia. SV showed a significant dose-dependent decrease however, CO did not show significant change. SVR decreased significantly at higher dose. PEP was prolonged and PEP/ET increased significantly at the highest dose. From these results, it became clear that SV decreases dose-dependently due to decrease of cardiac contractility during anesthesia with continuous propofol infusion in horses. On the other hand, since MAP and CO did not show significant changes, total intravenous anesthesia with propofol was suggested to be suitable for long-term anesthesia in horses. 相似文献
117.
Shoji Ohta 《Genetic Resources and Crop Evolution》2017,64(8):2009-2020
Aegilops geniculata Roth, a wild relative of wheat (2n = 4x = 28, genome UUMM), is distributed over the Mediterranean basin and nearby areas. The species consists of two subspecies, subsp. geniculata and subsp. gibberosa (Zhuk.) Hammer. The former is distributed over the whole species area and has been genetically analyzed, and the latter is endemic to Spain and North Africa and has not been genetically evaluated. In this study, to clarify the genetic variation and delineation of the two subspecies from a biosystematic viewpoint, morphological variation among 23 accessions of subsp. geniculata and three of subsp. gibberosa and chromosome pairing at meiosis and fertility in their intra- and inter-subspecific F1 hybrids were examined. A principal component analysis based on the 11 spike characteristics clearly divided the 26 accessions into two groups representing the two subspecies. The inter-subspecific F1 hybrids showed significantly lower frequencies of chromosome pairing, significantly higher frequencies of multivalents, and significantly lower fertilities relative to those of the intra-subspecific F1 hybrids. It was concluded that wide-ranging cytogenetic variation is included in subsp. geniculata, that subsp. gibberosa, the intra-subspecific variation of which is small, is morphologically and cytogenetically differentiated from subsp. geniculata beyond the range of the intra-subspecific variation of subsp. geniculata, and that the two subspecies are effectively isolated reproductively by hybrid sterility. The results strongly suggested that western North Africa is one of the important diversity centers of Ae. geniculata, where two subspecies were differentiated in the past and grow together in the present. 相似文献
118.
119.
Expression of hemagglutinin of Haemophilus paragallinarum serotype A in Escherichia coli. 总被引:1,自引:0,他引:1
M Takagi K Ohmae N Hirayama S Ohta 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(5):917-920
The genomic DNA of Haemophilus paragallinarum (Hpg) serotype A strain 221 was cloned into vector plasmid pBR322. The recombinant plasmids were introduced into Escherichia coli (E. coli) strain C600. Subsequently, a total of 277 transformants were obtained. One, designated strain no. 6, expressed hemagglutination activity against chicken erythrocytes. Strain no. 6 contained the recombinant plasmid pNV102, and DNA of about 2.57 kb was inserted into pNV102. When strain no. 6 was cured of pNV102, the strain lost hemagglutination activity. When the cured strain was retransformed with pNV102, hemagglutination activity was restored. E. coli strain no. 6 reacted with monoclonal antibody specific to the hemagglutinin of Hpg serotype A in a dot-blotting analysis. Chickens immunized with the inactivated strain no. 6 produced the hemagglutination inhibition (HI) antibody, and chickens possessing the HI antibody showed protection against challenge exposure by Hpg strain 221. 相似文献
120.
Osawa T Morishige D Ohta D Kimura Y Miyake Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(4):459-464
To investigate the viability of timed artificial insemination (TAI) protocols in grazing Japanese Black cattle with long open period, ovarian status and progesterone and estradiol-17 beta profiles of the animals during the protocol were monitored. In 1998, prosta-glandin F(2a) (PG) was administered to 36 animals seven days after GnRH injection. Three out of the 36 animals were inseminated after detection of estrus and did not receive further treatment. The second GnRH was injected to the remaining 33 animals 48 hr after the PG injection and TAI was performed 24 hr later. In 1999, PG was injected to 25 animals six days after GnRH, the second GnRH was injected to 22 animals 48 hr after PG, and TAI was performed 16 hr later (The other three animals were inseminated before the time of TAI). The percentage of the animals with at least one functional corpus luteum and one follicle equal to or greater than 10 mm in diameter at PG injection was similar between the groups in 1998 and 1999. Likewise, the hormonal profiles were similar between the two groups. Pregnancy rates (PR) after the TAI protocols and natural mating in 1998 and 1999 were 75.0% and 88.0%, respectively. These figures were comparable to the PR obtained by conventional estrus synchronization protocols using PG (in 1995; 69.4%) or CIDR (in 1996; 59.1%). In conclusion, the TAI protocol can be applicable into grazing Japanese Black cattle with long open period. 相似文献