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41.
42.
Four calves experimentally infected with different doses of Strongyloides papillosus were examined for changes of body temperature and other clinical parameters. Also, the critical moments of death, which were recorded on videotape, were analyzed in detail. The first clinical signs included initial accelerated respiration. In general, body temperature was almost normal; however, one calf showed a slight increase after 2 or 3 days of infection, and two calves a gradual increase 7 days after infection. Vocal noises and general spasms were observed 5-14 times during the course of death. Initial vocal noises were heard between 0:50 and 1:30 (minute:second) after the appearance of the initial clinical signs. The final spasm, preceding death, occurred between 3:05 and 3:40 after the appearance of the initial clinical signs.  相似文献   
43.
ABSTRACT:     Four steroidal ketones were isolated from the holdfast of cultivated Laminaria japonica . The structures were characterized as ergosta-4,24(28)-diene-3-one (1), ergosta-4,24(28)-diene-3,6-dione (2), stigmasta-4,24(28)-diene-3-one (3) and stigmasta-4,24(28)-diene-3,6-dione (4), by spectral data. Compounds 2 and 4 were shown to be cytotoxic against the MCF-7 human breast cancer cell, and the growth of MCF-7 was inhibited by 96% and 79%, respectively, at 10 µg/mL. It is the first report on the isolation of cytotoxic steroidal ketones from the kelp in the genus of Laminaria.  相似文献   
44.
Myostatin (MSTN), known as growth and differentiation factor 8 (GDF-8), is a member of the transforming growth factor β (TGF-β) superfamily that negatively regulates skeletal muscle mass. Myostatin binds with high affinity to the receptor serine threonine kinase activin receptor type IIB (ActRIIB). Activins that also belong to the TGF-β superfamily, stimulate follicle-stimulating hormone production in gonadotrophs and suppress growth hormone and adrenocorticotropic hormone production in somatotrophs and corticotrophs, respectively. The aim of the present paper was therefore to clarify the endocrine action of MSTN in adenohypophysis. The present study details the expression and cellular localization of MSTN and ActRIIB in porcine anterior pituitary gland. The mRNA of MSTN and ActRIIB was consistently expressed in RT-PCR. Immunohistochemistry of MSTN and specific hormones showed that MSTN localized in thyrotrophs and gonadotrophs, in which most of the MSTN immunoreactive cells were identified as thyrotrophs. The immunostaining of ActRIIB was restricted to corticotrophs. These results indicate that MSTN was mainly produced in thyrotrophs and its receptor, ActRIIB, was restrictively contained in corticotrophs. Interestingly, thyrotrophs immunoreactive for MSTN were frequently close to corticotrophs immunoreactive for ActRIIB. The present study suggests that MSTN from thyrotrophs may regulate corticotroph function as a paracrine mediator among the porcine anterior pituitary cells.  相似文献   
45.
We evaluated the influence on milk production of feeding early lactation cows a diet that included 14.5% crude protein (CP) and that did not meet methionine (Met) requirements or that met them by supplying rumen‐protected Met (RPMet). Thirty‐nine multiparous Holstein cows were allocated into two groups. For 15 weeks after calving, each group was fed one of the two total mixed rations, Control (= 20) or Treatment (= 19). The Treatment group received added RPMet at 0.034% (8 g/day) of the Control diet on dry matter basis. The adequacies of Met for the Control and Treatment groups were 96% and 106%, respectively, and for other amino acids, >110%. The CP level (14.5%) was 1 percentage point lower than that recommended by the Japanese Feeding Standard (2006). No between‐group differences were found in milk yield (40 kg/day), milk composition, plasma profile, rumen fermentation, nitrogen balance, or cow health. Met intake and the amount of rumen‐undegradable feed Met were higher in the Treatment group (< 0.05). Microbial Met and total metabolizable Met did not differ between groups. Supplying RPMet in a 14.5% CP diet during early lactation did not dramatically affect milk production, because the amount of total metabolizable Met was unchanged.  相似文献   
46.
Objective Fatty liver Shionogi (FLS) mice exhibit characteristic retinochoroidal coloboma because of a failure in fusion of the embryonic optic fissure. However, the same pathogenesis should result in iridal coloboma that has not been reported in this strain. The purpose of this study was to describe the physiologic and morphometric changes in iridal tissue involved in ocular coloboma in FLS mice. Procedures The miotic response after light exposure was evaluated in three strains of live mice, and the shape and location of the pupil were judged macroscopically. Subsequently, macroscopic abnormalities in the anterior segment and fundus were observed postmortem in all mice. During miotic and mydriatic responses in the eyes of live male FLS mice with dyscoric and normal pupils, each iris was measured in four radial directions. The enucleated eyes were examined morphometrically and histologically in both sexes of FLS mice. Results Inferior corectopia upon light‐induced miosis was clearly detected in live FLS mice. The deviated pupils were not round but oval‐shaped. Clinical and postmortem examination revealed that all dyscoric eyes had hypoplastic and dysfunctional irides inferiorly in FLS mice. Histopathological examination confirmed that both the dilator and sphincter muscles and iris stroma were quantitatively diminished in the affected inferior iris. Meanwhile, the rate of fundus (retinochoroidal) coloboma in eyes exhibiting dyscoria was remarkably high, although some dyscoric eyes had no fundus coloboma. Conclusions Fatty liver Shionogi mice had iridal coloboma, resulting in inferior corectopia upon light‐induced miosis as an indicator of ocular coloboma.  相似文献   
47.
Pro-inflammatory cytokine interleukin 18 (IL-18) has been proposed to have a role in modulating immuno-endocrine functions. Our previous study showed that IL-18 and IL-18 receptor (IL-18R) colocalized in somatotrophs of the bovine anterior pituitary gland, and the possibility that IL-18 acts on somatotrophs as an autocrine factor. In the present study, we investigated the localization of IL-18 and IL-18R in the pig anterior pituitary gland. RT-PCR analysis showed the expression of IL-18 and IL-18R mRNAin the pig anterior pituitary gland. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs, mammotrophs, thyrotrophs and gonadotrophs. IL-18R was localized in somatotrophs and thyrotrophs. Furthermore, the somatotrophs immunoreactive for IL-18 did not contain IL-18R. Thus, IL-18R and IL-18 were not colocalized in an identical somatotroph. These findings suggest that the localization of IL-18 in pig somatotrophs is different from that in bovine somatotrophs, although IL-18 closely associates with somatotrophs in the anterior pituitary glands in both species.  相似文献   
48.
To clarify the crucial role of Toll-like receptor (TLR) 2 and TLR9 in immature gut-associated lymphoid tissues (GALT), we focused on the expression of TLR2 and TLR9 and the immune responses induced by their ligands in the GALT of presuckling newborn swine. Quantitative real-time PCR revealed that TLR2 and TLR9 mRNA were expressed at detectable levels in all tested tissues (heart, thymus, lung, spleen, liver, kidney, skeletal muscle, duodenum, jejunum, ileum, ileal Peyer patches (Pps), and mesenteric lymph nodes (MLN)). In particular, in immature intestinal tissues and GALT, TLR2 and TLR9 mRNA were expressed at higher levels in ileal Pps and MLN than in the duodenum, jejunum, and ileum. We confirmed that the TLR2 and TLR9 proteins were also highly expressed and that their ligands were preferentially recognized by TLR2- or TLR9-expressing cells in the MLN and ileal Pps. Zymosan, CpG2006, and lactic acid bacteria could promote mitogenesis and production of multiple cytokines by the MLN and ileal Pps. In addition, double immunostaining for cytokeratin 18 and either TLR2 or TLR9 revealed that both TLR2 and TLR9 are strongly expressed in the columnar membranous (M) cells. Interestingly, while the apical membrane of the columnar M cells strongly expressed TLR2 protein and preferentially recognized zymosan, both "TLR2 expression on the apical membrane" and "TLR2-mediated zymosan binding" were negligible in neighboring enterocytes. These results indicate that TLR2 and TLR9 allow MLN and ileal Pps to respond to a variety of bacterial components immediately after birth, thereby providing newborns with a host defense system.  相似文献   
49.
To investigate the surface antigens of the bovine red blood cells (RBCs) parasitized by Babesia ovata or Theileria sergenti, attempts were made to produce monoclonal antibodies (mAbs) with BALB/c mice. Comparable numbers of hybridomas producing anti-piroplasm mAbs, as well as anti-bovine RBC mAbs, were obtained from the mice immunized with B. ovata- or T. sergenti-PRBCs. However, mAbs directed to the surface of parasitized RBCs (PRBCs) were obtained only from the mice immunized with B. ovata-PRBCs, but not from those immunized with T. sergenti-PRBCs. When serum samples from the immunized mice and the infected cattle were examined, antibodies recognizing B. ovata-PRBC surface were detected in the sera against B. ovata, but analogous antibodies were undetectable in the sera against T. sergenti, despite that the sera showed substantial antibody titers to T. sergenti piroplasms. The results suggest that significant antigenic modifications occur on the surface of B. ovata-PRBCs, but not on the surface of T. sergenti-PRBCs.  相似文献   
50.
OBJECTIVE: To examine the effects of various doses of mosapride, a 5-hydroxytryptamine 4 receptor agonist, on motility of the small intestine and cecum in horses by use of electrical activity and to determine the dose that provides the optimal response. ANIMAL: 6 healthy adult Thoroughbreds. PROCEDURE: Electrical activity of the small intestine and cecum was recorded before and after mosapride administration by use of an electrogastrograph. Mosapride (0.5, 1, 1.5, and 2 mg/kg) was dissolved in 200 mL of water and administered orally to horses through a nasogastric tube. Three hours after drug administration, mean amplitude of electrical activity calculated for a period of 30 minutes was expressed as the percentage of the mean amplitude of electrical activity for a period of 30 minutes before drug administration. RESULTS: Mosapride administered orally increased the percentage of the mean amplitude of electrical activity in the small intestine and cecum in a dose-dependent manner. Mean +/- SD values differed significantly for 1, 1.5, and 2 mg/kg (127.0 +/- 12.5%, 137.7 +/- 22.2%, and 151.1 +/- 24.0%, respectively) in the small intestine and for 1.5 and 2 mg/kg (130.1 +/- 34.5% and 151.6 +/- 45.2%, respectively) in the cecum. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of results of this study clearly documents that mosapride promotes motility in the small intestine and cecum of horses and that the optimal orally administered dosage is 1.5 to 2 mg/kg. Therefore, mosapride may be useful for treatment of horses with gastrointestinal tract dysfunction.  相似文献   
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