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| Registros recuperados: 77 | |
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| ACOSTA, Tomas J.; HAYASHI, Ken-Go; MATSUI, Motozumi; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫. |
| Increase in the blood supply to individual follicles appears to be associated with follicular growth rates and the ability to become the dominant follicle, while reduced thecal vascularity appears to be closely associated with follicular atresia. Therefore, this study aimed to determine the real-time changes in the vascularity of the follicle wall during the first follicular wave in cycling Holstein cows. Normally cycling and lactating cows (n=5) were examined by transrectal color Doppler ultrasonography (the sensitivity for velocity: > 2 mm/sec) to determine the changes in the vasculature of the follicle wall (presence or absence of blood flow) and the diameter of follicles. A new follicular wave and ovulation were induced by GnRH injection at 48 h... |
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Palavras-chave: Blood flow; Follicular wave; Selection; Deviation; Cow. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2979 |
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| ACOSTA, Tomas J.; TETSUKA, Masa; MATSUI, Motozumi; SHIMIZU, Takashi; BERISHA, Bajram; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 清水, 隆; 宮本, 明夫. |
| The aim of the present in vivo study was to monitor real-time fluctuations of cortisol (Cr) in the wall of preovulatory follicles using a microdialysis system (MDS) implanted in the theca layer as well as changes in ovarian venous plasma (OVP) and jugular venous plasma (JVP). Seven cows were superovulated using FSH and prostaglandin F2α injections. Dialysis capillary membranes were surgically implanted into the theca layer of mature follicles and connected to a microdialysis system. Fractions of the perfusates were collected from Day -1 (Day 0=LH surge) to Day 3. No difference in the concentrations of Cr between JVP and OVP was detected throughout the experiment. Circulating concentrations of Cr ranged from 20 to 35 ng/ml 8 h after surgery in ovulatory and... |
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Palavras-chave: Bovine; Cortisol; Follicle; Ovary; Ovulation. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2980 |
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| BEINDORFF, Nicola; NAGAI, Kaya; SHIRASUNA, Koumei; HERZOG, Kathrin; HOEFFMANN, Katharina; SASAKI, Motoki; BOLLWEIN, Heinrich; MIYAMOTO, Akio; 佐々木, 基樹; 宮本, 明夫; 白砂, 孔明. |
| The present study determined vascular changes in the bovine corpus luteum (CL) at Day 16 (early maternal recognition period) and Day 40 in early pregnancy and compared them to the CL from Day 12 and Day 16 of the estrous cycle. The CLs were analyzed in the central and peripheral regions, where site-depending features of vessels and angiogenic factors are evident. The same protein level of the endothelial cell marker von Willebrand factor was retained in the CL from Day 16 of the estrous cycle to Day 40 of early pregnancy. The protein level of pericytes and smooth muscle cells was determined using smooth muscle α-actin; the level decreased at Day 40 of early pregnancy in both regions of the CL. No significant change in the expressions of vascular... |
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Palavras-chave: Corpus luteum; Cow; Early pregnancy; Endothelial cells. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2811 |
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| Fukui, Yutaka; Yamamura, Kunio; Matsunaga, Nobuyoshi; Miyamoto, Akio; 福井, 豊; 宮本, 明夫. |
| The present study aimed to examine the possibility that bovine somatotropin (BST) treatment after artificial insemination (AI) may improve the fertility by the stimulation of corpus luteum (CL) function in seasonally anestrous ewes. The experiment was conducted at the Tawa Field Station, Shibecha-cho in Hokkaido, Japan, during the non-breeding season (May, 1995). Eighty-nine mature (2 to 3 years old) Suffolk and Suffolk-crossed ewes were treated with controlled internal drug release devices containing 0.3 g progesterone (CIDR-G) for 12 days. Ewes were injected intramuscularly with 500 IU PMSG the day before CIDR removal. Eighty-seven ewes were assigned to an insemination of frozen semen on a fixed-time basis (42 to 50 h) after removal of CIDR. On the 11th... |
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Palavras-chave: Bovine somatotropin; Artificial insemination; Progesterone; Conception rate; Ewes. |
| Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2971 |
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| HAYASHI, Ken-Go; BERISHA, Bajram; MATSUI, Motozumi; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫. |
| Recent findings indicate that the changing profile of angiopoietins (ANPT) and their receptor Tie2 are closely associated with development and regression of the vascular network in the cyclic ovary. We previously reported that mRNA expression for the ANPT-Tie system in theca interna changes during bovine follicular development and atresia, and both ANPTs affect steroidogenesis in the preovulatory follicle. The aim of this study was to investigate mRNA expression for ANPT1, ANPT-2 and Tie2 in granulosa cells (GC) during follicular development in the cow. Bovine follicles were classified according to the estradiol-17β (E2) concentration in follicular fluid (FF) as follows: (1) E2<0.5, (2) 0.5<E2<5, (3) 5<E2<20, (4) 20<E2<180 and (5)... |
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Palavras-chave: Follicular development; Angiopoietin-Tie system; Granulosa cell; Cow. |
| Ano: 2004 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2975 |
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| HAYASHI, Ken-Go; MATSUI, Motozumi; ACOSTA, Tomas J.; KIDA, Katsuya; MIYAMOTO, Akio; 松井, 基純; 木田, 克弥; 宮本, 明夫. |
| Luteinizing hormone (LH) surge and follicle rupture act as trigger to start corpus luteum (CL) formation. Thus, we aimed to investigate whether a dominant follicle that has not been exposed to an LH surge can become a functional CL. For this purpose, follicular fluid from the dominant follicles (DF) of cows was aspirated before or after a GnRH-induced LH surge, and subsequent CL formation was observed. Holstein cows were divided into four groups as follows: Luteal phase, a DF was aspirated 7 days after GnRH injection; Pre-LH surge, a DF was aspirated 42 h after PGF2α injection during the mid luteal phase; Post-LH surge, a DF was aspirated 24 h after GnRH injection following PGF2α; and Intact follicle, ovulation was induced by GnRH injection after PGF2α.... |
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Palavras-chave: Corpus luteum formation; Cow; Follicle aspiration; LH surge. |
| Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2982 |
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| HORI, Takuya; YAMSAARD, Thicomeporn; UETA, Yoshiko Yanagimoto; HARAKAWA, Shinji; KANEKO, Etsushi; MIYAMOTO, Akio; XUAN, Xuenan; TOYODA, Yutaka; SUZUKI, Hiroshi; 宮本, 明夫; 玄, 学南; 鈴木, 宏志. |
| It is well-known that there are considerable strain differences in the relative copulation rates between male and superovulated female mice. In particular, the C57BL/6J strain of mice has a lower rate of successful copulation. We examined the effect of exposure to an electric field on sexual behavior in C57BL/6J male mice. When C57BL/6J males were exposed to a 50 Hz, 45 kV/m electric field for 30 min per day for 11 days and placed in a cage with a superovulated female of the same strain, the successful copulation rates of males was significantly improved compared with unexposed males (P<0.05). These results suggest that the exposure of C57BL/6J male mice to an electric field improves their sub-fertility activity in mating with superovulated females. |
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Palavras-chave: Mice; Male; Electric field; Copulation; Superovulation; Sexual behavior. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3021 |
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| ISHII, Mitsuo; KOBAYASHI, Syuichi; ACOSTA, Tomas J.; MIKI, Wataru; YAMANOI, Takahiro; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; MIYAMOTO, Akio; 石井, 三都夫; 松井, 基純; 三宅, 陽一; 宮本, 明夫. |
| The aim of this study was to clarify the relationship between circulating oxytocin (OT) and PGF2α metabolite (PGFM) in mares at the third stage of labor and placental expulsion time in order to investigate a cause of retained placenta of which the incidence increase in a heavy draft mare. Blood was sampled every 5 min from foaling to expulsion of the placenta in 18 heavy draft mares to evaluate circulating OT and PGFM. The relationships between OT and PGFM concentration and recorded placental expulsion times were investigated. The results were as follows (1) The highest level of OT concentration was observed close to foaling in 15 mares. (2) The OT concentrations close to foaling were variable with a large difference from the lowest concentration, 22.1... |
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Palavras-chave: Heavy draft mare; Oxytocin; 15-keto-dihydro prostaglandin F2α (PGFM); Placental expulsion. |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3089 |
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| KAWASAKI, Yurie; AOKI, Yuka; MAGATA, Fumie; MIYAMOTO, Akio; KAWASHIMA, Chiho; HOJO, Takuo; OKUDA, Kiyoshi; SHIRASUNA, Koumei; SHIMIZU, Takashi; 宮本, 明夫; 清水, 隆. |
| The present study aimed to assess the effect of polymorphisms in the tumor necrosis factor α (TNF-α) promoter (A/A, A/G and G/G) and exons (T/T, T/C and C/C) on immune function and reproductive performance in dairy cows. The occurrence of the first postpartum ovulation within 3 weeks in the cows with the TNF-α promoter A/G and G/G genotypes was higher than in the A/A group. Among the different TNF-α exon genotypes, the occurrence of early first postpartum ovulation was higher in the T/C and C/C genotype groups than in the T/T group. Single nucleotide polymorphisms (SNPs) in the TNF-α gene did not affect the rate of artificial insemination (AI) or duration from parturition to next conception (days open). The apoptosis rate of polymorphonuclear leukocytes... |
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Palavras-chave: Cattle; Immune function; Polymorphism; Reproductive performance; Tumor necrosis factor α (TNF-α). |
| Ano: 2014 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3934 |
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| Kawashima, Chiho; Fukihara, Saori; Maeda, Mayumi; Kaneko, Etsushi; Montoya, Carlos Amaya; Matsui, Motozumi; Shimizu, Takashi; Matsunaga, Nobuyoshi; Kida, Katsuya; Miyake, Yoichi; Schams, Dieter; Miyamoto, Akio; 川島, 千帆; 松井, 基純; 清水, 隆; 木田, 克弥; 三宅, 陽一; 宮本, 明夫. |
| Recent studies suggest that IGF-I is a crucial regulatory factor in follicular growth during early post-partum period. The aim of the present study was to determine in detail the changing profiles of metabolic and reproductive hormones in relation to ovulation of the dominant follicle (DF) of the first follicular wave post-partum in high-producing dairy cows. Plasma concentrations of related hormones in 22 multiparous Holstein cows were measured from 4 weeks pre-partum to 3 weeks post-partum, and the development of DF was observed with colour Doppler ultrasound. Thirteen cows showed ovulation by 15.2 days post-partum. Anovulatory cows showed higher GH and lower IGF-I levels than those in ovulatory cows during the peri-partum period. Each DF developed... |
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Palavras-chave: GROWTH-FACTOR-I; COMPETITIVE ENZYME-IMMUNOASSAY; ENERGY-BALANCE; OVARIAN ACTIVITY; STIMULATING-HORMONE; ESTRADIOL PRODUCTION; BODY CONDITION; MESSENGER-RNA; HOLSTEIN COWS; IGF-I. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1658 |
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| KAWASHIMA, Chiho; ITO, Nozomi; NAGASHIMA, Shuntarou; MATSUI, Motozumi; SAWADA, Kumiko; SCHWEIGERT, Florian J.; MIYAMOTO, Akio; KIDA, Katsuya; 川島, 千帆; 松井, 基純; 宮本, 明夫; 木田, 克弥. |
| The aim of the present study was to investigate nutritional and metabolic parameters during the dry and early postpartum periods of ovulatory and anovulatory cows, as well as their postpartum reproductive performance. Blood samples from 20 multiparous Holstein cows were collected once a week from the far-off dry period to 3 weeks postpartum. Early postpartum (0–3 weeks) ovulation was confirmed using plasma progesterone concentration profiles, and cows were considered ovulatory if they had resumed luteal activity by this point (n = 9), whereas cows that had not were considered anovulatory (n = 11). Data from the ovulatory and anovulatory cows were analyzed separately for the far-off dry period (7–4 weeks prepartum), the close-up dry period (3–1 weeks... |
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Palavras-chave: Dairy cow; First ovulation; Hepatic enzyme; Liver function; Reproductive performance. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4308 |
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| KAWASHIMA, Chiho; KANEKO, Etsushi; AMAYA MONTOYA, Carlos; MATSUI, Motozumi; YAMAGISHI, Norio; MATSUNAGA, Nobuyoshi; ISHII, Mitsuo; KIDA, Katsuya; MIYAKE, Yoichi; MIYAMOTO, Akio; 川島, 千帆; 松井, 基純; 石井, 三都夫; 木田, 克弥; 三宅, 陽一; 宮本, 明夫. |
| The aim of this study was to investigate the relationship between the first ovulation within 3 weeks postpartum and subsequent ovarian cycles and fertility in high producing dairy cattle in Hokkaido, Japan. In Experiment 1, 110 cows (44 primiparous and 66 multiparous) were used to determine the effects of the first ovulation within 3 weeks postpartum on subsequent ovarian cycles. Milk samples were collected twice weekly from 7 to 100 days postpartum. The first ovulation was identified by an increase in milk progesterone (P4) to more than 1 ng/ml within 3 weeks postpartum. The numbers of cows showing ovulation and anovulation within 3 weeks postpartum were 31 (70.5%) and 13 (29.5%) in the primiparous cows and 35 (53.0%) and 31 (47.0%) in the multiparous... |
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Palavras-chave: Dairy cow; First ovulation; Postpartum; Resumption of ovarian cycle. |
| Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/916 |
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| KAWASHIMA, Chiho; KIDA, Katsuya; HAYASHI, Ken-Go; AMAYA MONTOYA, Carlos; KANEKO, Etsushi; MATSUNAGA, Nobuyoshi; SHIMIZU, Takashi; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; SCHAMS, Dieter; MIYAMOTO, Akio; 川島, 千帆; 木田, 克弥; 清水, 隆; 松井, 基純; 三宅, 陽一; 宮本, 明夫. |
| The aim of the present study was to investigate the changing profiles of plasma metabolic hormones during the ovarian cycles of beef and dairy cattle. We used 16 non-pregnant, non-lactating Japanese Black beef cattle (6 heifers and 10 cows; parity=2.3 ± 0.8) and 12 multiparous Holstein dairy cows (parity=3.0 ± 0.3). Blood samples for hormonal analysis (growth hormone, GH; insulin-like growth factor-I, IGF-1; insulin; and progesterone, P4) were obtained twice weekly for 40 days before artificial insemination for Japanese Black cattle and from 50 to 100 days postpartum for Holstein cows. Luteal phases were considered normal if the P4 concentrations for at least 3 time points over the course of 7 days remained above 1 ng/ml and at least 2 of the time points... |
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Palavras-chave: Cattle; Insulin-like growth factor-I; Ovarian cycle; Progesterone. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2984 |
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| KAWASHIMA, Chiho; KIDA, Katsuya; MATSUHASHI, Miki; MATSUI, Motozumi; SHIMIZU, Takashi; MATSUNAGA, Nobuyoshi; ISHII, Mitsuo; MIYAKE, Yoh-Ichi; MIYAMOTO, Akio; 川島, 千帆; 木田, 克弥; 松井, 基純; 清水, 隆; 石井, 三都夫; 三宅, 陽一; 宮本, 明夫; 松長, 延吉. |
| The aim of our study was to investigate the effects of suckling on reproductive performance and metabolic status of obese (mean body condition score of more than 4.0 on a scale of 1-5) maternal Japanese Black cows during early postpartum period. We used 7 postpartum Japanese Black cattle. Four cows were suckled ad libitum (suckled) until completion of their first artificial insemination (AI), while 3 cows were not suckled at all because they were separated from their calves immediately after parturition (non-suckled). Body weight and plasma concentrations of metabolites and hormones were measured from wk 1 to 9 postpartum. Ovarian activity was detected using plasma progesterone concentration, and all cows received their first AI after application of the... |
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Palavras-chave: Japanese Black cattle; Metabolic status; Obesity; Reproductive performance; Suckling. |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2991 |
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| KAWASHIMA, Chiho; MATSUI, Motozumi; SHIMIZU, Takashi; KIDA, Katsuya; MIYAMOTO, Akio; 川島, 千帆; 松井, 基純; 清水, 隆; 木田, 克弥; 宮本, 明夫. |
| During recent decades, milk production per cow has increased drastically due to improved management, nutrition, and genetic selection; however, the reproductive performance of high-producing dairy cows has been declining. One of the factors responsible for this low reproductive performance is negative energy balance (NEB). NEB affects the onset of first ovulation in early postpartum cows. It is generally accepted that early first ovulation positively relates to the resumption of normal ovarian function, first service, and conception rate in dairy cows. Hence, delayed first ovulation has a negative impact on subsequent fertility. The metabolic condition of cows in NEB shifts to catabolic metabolism, which in turn causes increased plasma growth hormone and... |
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Palavras-chave: Β-Carotene; Dairy cow; First follicular wave postpartum; First ovulation; Metabolic hormone. |
| Ano: 2012 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4041 |
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| KAWASHIMA, Chiho; MUNAKATA, Megumi; SHIMIZU, Takashi; MIYAMOTO, Akio; KIDA, Katsuya; MATSUI, Motozumi; 川島, 千帆; 清水, 隆; 宮本, 明夫; 木田, 克弥; 松井, 基純. |
| This study aimed to investigate the effects of insulin resistance (IR) during the close-up dry period on the metabolic status and performance of dairy cows as well as to determine the effects on body weight (BW) and metabolic status of their calves. An insulin tolerance test (ITT) was conducted by administering 0.05 IU/kg BW of insulin to 34 multiparous Holstein cows at 3 weeks prepartum. Blood samples were collected at 0, 30, 45 and 60 min after insulin injection, and cows were divided into two groups based on the time required for glucose to reach the minimum levels [non-IR (NIR), 45 min (n=28); and IR, 60 min (n=6)]. Blood or milk sampling and body condition score (BCS) estimation were performed twice weekly during the experimental period. Blood samples... |
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Palavras-chave: Dairy cow; Dry period; Insulin tolerance test; Metabolic status; Postpartum performance. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4363 |
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| KOBAYASHI, Shu-ichi; ACOSTA, Tomas J.; HAYASHI, Kanako; BERISHA, Bajram; OZAWA, Takahiro; OHTANI, Masayuki; SCHAMS, Dieter; MIYAMOTO, Akio; 宮本, 明夫. |
| It is well known that prostaglandin (PG) F2α and PGE2 are actively produced by bovine early corpus luteum (CL) at higher levels than in the CL of later stages. However, there is no in vivo information about the local secretion of PGs within bovine developing CL so far. Thus, the objective of the present study was to determine in detail the real-time changes in PGF2α and PGE2 secretion within developing CL. A microdialysis system (MDS) was surgically implanted into the newly formed CL of 6 cows on Day 3 after GnRH administration (about 1.5 days after ovulation) to induce superovulation following FSH treatment. Both PGF2α and PGE2 release were high during the first 24 h within developing CL but decreased thereafter. These profiles were well reflected in the... |
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Palavras-chave: PGF2α; PGE2; Developing CL; Cow; In vivo. |
| Ano: 2002 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2974 |
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| KOBAYASHI, Shu-ichi; MIYAMOTO, Akio; 宮本, 明夫. |
| Luteal cells utilize lipoproteins (LIPs) for progesterone (P) synthesis. A luteolysin prostaglandin F2α (PGF 2α) has shown to prevent the LIPs utilization for steroidogenesis in bovine midcycle luteal cells. However, a luteolytic injection of PGF2α before Day 5 (Day 0=estrus) can not induce the regression of the corpus luteum (CL). This suggests that the intraluteal mechanism of PGF2 α action on the LIPs utilization in early CL is different from that of the mid luteal stage. Thus, this study aimed to investigate the interaction between PGF2 α and LIPs on the secretion of P and oxytocin (OT) from bovine early CL. An in vitro microdialysis system (MDS) was used as a model. Each bovine early CL (Days 3-4) was implanted with the MDS, and maintained in an organ... |
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Palavras-chave: PGF2α; Lipoproteins; Early CL; Cow. |
| Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2972 |
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| KOWSAR, Rasoul; HAMBRUCH, Nina; LIU, Jinghui; SHIMIZU, Takashi; PFARRER, Christiane; MIYAMOTO, Akio; 清水, 隆; 宮本, 明夫. |
| This study aimed to investigate the role of epithelial cells in regulating innate immunity in bovine oviduct epithelial cell (BOEC) culture. We studied the effect of Escherichia coli lipopolysaccharide (LPS) and its interaction with ovarian steroids, estradiol (E2) and progesterone (P4), and luteinizing hormone (LH) at concentrations observed during the preovulatory period on immune responses in BOEC culture. Immunohistochemistry of oviduct tissue showed intensive expression of Toll-like receptor-4 (TLR-4) and TLR-2 in epithelial cells. A dose of 10 ng/ml LPS stimulated TLR-4, cyclooxygenase-2 (COX-2), nuclear factor kappa B inhibitor A (NFKBIA), interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) expression, indicating an early pro-inflammatory... |
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Palavras-chave: Bovine oviduct epithelial cell; Ovarian steroids; TLR-4; Th1/Th2 response. |
| Ano: 2013 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3937 |
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| Registros recuperados: 77 | |
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