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51.
Although whey acidic protein (WAP) has been identified in the milk of a range of species, it has been predicted that WAP is not secreted into human milk as a result of critical point mutations within the coding region. In the present study, we first investigated computationally the promoter region of mutated human WAP genes by comparing with those of other known WAP genes. Computational database analyses showed that the human WAP promoter region was highly conserved, as in other species with milk WAP. Next, we evaluated the activity of the human WAP promoter (2.6 kb) using a reporter gene assay. MCF-7 cells were stably transfected with the hWAP/hGH (human growth hormone) fusion gene, cultured on Matrigel, and treated with lactogenic hormones. Radioimmunoassay detected hGH in the culture medium, indicating that the human WAP promoter was responsible for the lactogenic hormones. The human WAP promoter was significantly more active in MCF-7 cells than the mouse WAP promoter (2.4 kb). The present results provide us with important information on the molecular evolution of milk protein genes.  相似文献   
52.
The central few hundred parsecs of the Milky Way host a massive black hole and exhibit very violent gas motion and high temperatures in molecular gas. The origin of these properties has been a mystery for the past four decades. Wide-field imaging of the (12)CO (rotational quantum number J = 1 to 0) 2.6-millimeter spectrum has revealed huge loops of dense molecular gas with strong velocity dispersions in the galactic center. We present a magnetic flotation model to explain that the formation of the loops is due to magnetic buoyancy caused by the Parker instability. The model has the potential to offer a coherent explanation for the origin of the violent motion and extensive heating of the molecular gas in the galactic center.  相似文献   
53.
A 12‐year‐old, male castrated Domestic Shorthair cat was presented to Animal Medical Center of Gifu Univeristy with anorexia and vomiting. Physical examination revealed an enlarged left tonsil and right mandibular lymph node (approximately 2–3× the normal size), and a submucosal mass on the right side of the epiglottis (1.5 × 2.0 cm). On computed tomography images, an enlarged left tonsil, and enlarged right mandibular, right pharyngeal, and left and right cervical lymph nodes were observed. Cytologic examination of smears of tonsil and lymph nodes revealed numerous medium‐ to large‐sized neoplastic lymphoid cells, approximately half of which contained one or several light‐blue homogenous globoid cytoplasmic inclusions (5–10 μm), which stained magenta with periodic acid–Schiff (PAS) stain. Histopathologic examination of the left tonsil revealed diffuse proliferation of medium‐ to large‐sized neoplastic lymphoid cells effacing the original lymphoid architecture. Half of the cells contained one or several eosinophilic globoid cytoplasmic inclusions, which stained magenta with PAS and showed positive immunohistochemical reactions for immunoglobulin M (IgM) and λ light chain. Neoplastic lymphoid cells were also CD20+, Pax5+, and MUM1+, and CD3?. Thus, the neoplastic lymphoid cells expressed a B‐cell immunophenotype, and the globoid cytoplasmic inclusions represented an aberrant IgM λ light chain accumulation, similar to Russell bodies. B‐cell lymphoma with Mott cell differentiation was diagnosed based on cytologic, histopathologic, and immunohistochemical features. This is the first report of B‐cell lymphoma with Mott cell differentiation in a cat.  相似文献   
54.
An 11-year-old male Labrador retriever presented with chronic oliguria. Ultrasonography findings revealed a protruding mass at the neck of the urinary bladder. A cystotomy was performed, and the mass was removed by ligation with surgical sutures. Histopathological examination revealed conspicuous foci with a variable number of ganglion cells in the tumor and abundant interwoven bundles of schwannian cells with fine fibers. The ganglion cells were positive for neuron-specific enolase and neurofilament. The schwannian cells were positive for vimentin, S-100 protein, and glial fibrillary acidic protein. Thus, according to the classification of tumor with neuronal cell differentiation, the urinary tumor was diagnosed as a ganglioneuroma.  相似文献   
55.
Strigolactones are highly potent germination stimulants for seeds of the parasitic weeds Striga and Orobanche spp. 4-Hydroxy-GR24 and 4-acetoxy-GR24 were prepared and their abilities to induce seed germination of Striga gesnerioides evaluated. Optically active (8bR,2'R)-isomers induced germination, although the racemic diastereomers were inactive. In contrast, the stereoisomer of GR24 with the same configuration induced negligible germination. Some stereoisomers of GR24 and its analogues acted as effective antagonists for induction of seed germination by cowpea root exudates. These results suggest that both an oxygenated substituent at C-4 and the configuration of the tricyclic lactone and the D-ring are essential structural requirements for induction of germination in S. gesnerioides seeds.  相似文献   
56.
The secretion rhythms of plasma cortisol (CORT) and prolactin (PRL), hormones related to stress responsiveness and biological rhythm and controlled by light and temperature, were investigated under varying external environments and different management techniques. Serial blood samples were collected from female cattle reared in free‐stall and freely fed (FF) conditions (n = 4) or in tie‐stall and restricted feeding (RF) conditions (hay and concentrate twice daily, n = 4). Plasma CORT and PRL concentrations, eating behavior, and environmental parameters were analyzed. Cyclic patterns for each parameter were examined using spectral analysis, and correlations between CORT, PRL and other parameters were investigated using cross‐spectral analysis. Under FF conditions, CORT secretion was not related to the lighting intensity and eating behavior. However, under RF conditions, the CORT secretion rhythm showed a distinct correlation with lighting intensity and eating behavior. Under FF conditions, the PRL secretion rhythm was similar in all seasons. However, under RF conditions, the PRL rhythm oscillated with high frequency in summer and low frequency in winter, indicating a seasonal change in rhythm. The present study demonstrates that hormone secretion rhythms change under different environments and management techniques.  相似文献   
57.
The use of the common marmoset monkey in biomedical research has increased recently, and further attention has been devoted to this model after the successful production of transgenic marmosets. To extend genetic engineering approaches to widespread biomedical research fields, efficient prolonged in vitro culturing of embryo development is necessary. We aimed to evaluate the effects of the size of the zona pellucida opening on promoting the hatching process in the marmoset embryo. Piezo‐microdrilling of a 6‐μm opening in eight embryos resulted in four partially hatched embryos and one hatched embryo after 5 days of culture. Piezo‐microdrilling a 20‐μm opening in 11 embryos resulted in nine partial hatchings and no hatched embryos. Piezo‐scraping an 80‐μm opening in six embryos resulted in no partially hatched embryos and five hatched embryos. These results suggest that an 80‐μm opening, rather than 6‐μm or 20‐μm openings, is suitable to complete the hatching process in the marmoset embryo.  相似文献   
58.
A male ferret, which was purchased from abroad at 9 months of age, had shown significant weight loss starting at 13 months of age. The ferret subsequently showed decreasing motor activity and recumbency and was euthanized at 14 months of age. At necropsy, a white, quail egg-sized mass was found in the mesentery. Histopathologically, multifocal granulomas consisting of necrotic foci, macrophages, fibroblasts and plentiful fibrous connective tissues were observed in the mesenteric mass. Surrounding the granulomas, inflammatory cell infiltration consisting of neutrophils, lymphocytes and plasmacytes was observed diffusely and significantly. Immunohistochemistry revealed small numbers of macrophages around necrotic foci that were positively stained for anti-mouse feline coronavirus. Electron microscopically, the cytoplasm of the macrophages contained viral particles, which were identified as coronavirus. The histopathological features in this ferret were similar to those in cats with feline infectious peritonitis (FIP). This was the first case in ferrets in Japan.  相似文献   
59.
In the present study, we investigated the hydrothermal treatment of titanium with divalent cation solutions and its effect in promoting the adhesion of gingival epithelial cells and fibroblasts in vitro. Gingival keratinocyte-like Sa3 cells or fibroblastic NIH3T3 cells were cultured for 1 h on experimental titanium plates hydrothermally-treated with CaCl(2) (Ca) or MgCl(2) (Mg) solution, or distilled water (DW). The number and adhesive strengths of attached cells on the substrata were then analyzed. The number of Sa3 cells adhering to the Ca- and Mg-treated plates was significantly larger than in the DW group, but the strength of this adhesion did not differ significantly between groups. In contrast, NIH3T3 cell adhesion number and strength were increased in both the Ca and Mg groups compared to the DW group. Fluorescent microscopic observation indicated that, in all groups, Sa3 had identical expression levels of integrin β4 and development of actin filaments, whereas NIH3T3 cells in the Ca and Mg groups displayed much stronger punctate cytoplasmic signals for vinculin and more bundle-shaped actin filaments than cells in the DW group. As a result, it was indicated that the hydrothermal treatment of titanium with Ca or Mg solution improved the integration of soft tissue cells with the substrata, which may facilitate the development of a soft tissue barrier around the implant.  相似文献   
60.
The objective of this study was to clarify the origin of the increase in plasma insulin-like growth factor-I (IGF-I) during estrus in goats. Focusing on the uterus, the effect of estradiol-17 beta (E2) on the secretion of IGF-I was examined using ovariectomized and hysterectomized animals. A single 5 microg/kg BW of E2 was injected intramuscularly into ovariectomized and hysterectomized goats for 3 consecutive days, and plasma IGF-I concentrations in the two groups were compared. The concentrations of IGF-I rose after the treatments in both groups. The concentrations were significantly higher from 3 to 8 days after the treatment than before the treatment in ovariectomized goats (P<0.05), and from 1 to 3 days after the treatment than before in hysterectomized goats (P<0.05). Thus higher concentrations of plasma IGF-I tended to last longer in ovariectomized than hysterectomized goats. The area under the IGF-I response curve for the 8-day period after the first injection of E2 tended to be greater in ovariectomized than in hysterectomized goats. The results show that E2 increases plasma IGF-I concentrations in goats, and suggest that E2-stimulated IGF-I in plasma may originate mainly from the uterus.  相似文献   
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