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51.
T cells are the dominant lymphocytes in the endometrium and are considered to play a crucial role in implantation and in the maintenance of gestation through cytokine production and immune regulation. The mechanisms underlying immunoregulation at the feto-maternal interface are still obscure for this complex system. Understanding the role of T cells is a key factor in understanding the endometrial immune system. In this study, the distribution of endometrial CD3+ T cells in bovines was examined by immunohistochemical analysis. The estrous cycle and gestation was divided into 4 stages, and the number of CD3+-positive T cells was counted in each stage. CD3+ cells were found in the endometrium in significant numbers throughout the estrous cycle and were mostly located in the subepithelial area. The number of CD3+ cells significantly increased in the early and mid-luteal phases but decreased after implantation with the progression of gestation. No T cells were found in the placentome or specifically in the tissues near the fetus, including the trophoblastic area. In addition, very few T cells were found in stromal regions close to the myometrium of the endometrium. These findings suggest that downregulation of bovine endometrial CD3+ T-cell functions is closely related to the successful maintenance of gestation in a spatiotemporal manner.  相似文献   
52.
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   
53.
TMV 2 is a very popular peanut variety among the Indian farmers, but it is highly susceptible to fungal foliar diseases like late leaf spot (LLS) and rust. Marker‐assisted backcrossing (MABC) in TMV 2 using foliar disease‐resistant donor, GPBD 4 and the disease resistance‐linked markers (GM2009, GM2079, GM2301, GM1839 and IPAHM103) resulted in a large number of backcross populations and also straight cross populations. Foreground selection followed by field evaluation under disease epiphytotic conditions could identify a few superior genotypes. Two homozygous backcross lines TMG‐29 and TMG‐46 showed enhanced resistance to LLS and rust diseases (score of 3.00 for both) along with 71.0% and 62.7% increase in the pod yield per plot, respectively, over the check, TMV 2. These foliar disease‐resistant and productive lines can be released as commercial varieties or can be used as genetic resources in the peanut improvement.  相似文献   
54.
Truncated recombinant nucleocapsid proteins (trNs) that lack N-terminally located cross-reactive epitopes of four Murinae rodent-associated hantaviruses, Seoul virus (SEOV), Thailand virus, Hantaan virus (HTNV) and Dobrava-Belgrade virus, were produced by using a baculovirus expression system. ELISA with the trNs as antigens enabled serotyping of immune sera from rats experimentally inoculated with the corresponding hantaviruses with cut-off OD values of 60% of those of whole N of HTNV. The trN-based ELISA could serotype 12 out of 13 sera obtained from wild rodents (Rattus norvegicus) naturally infected with SEOV using the 60% cut-off value. These results indicate that screening with whole N followed by serotyping with trNs using a cut-off OD value of 60% of that of whole N is a useful method for serological surveillance of Murinae-associated hantavirus infection among rodents.  相似文献   
55.
The secretion of prolactin (PRL) is under the dominant and tonic inhibitory control of dopamine (DA); however, we have recently found that salsolinol (SAL), an endogenous DA‐derived compound, strongly stimulated the release of PRL in ruminants. The aim of the present study was to clarify the inhibitory effect of DA on the SAL‐induced release of PRL in ruminants. The experiments were performed from late June to early July. Male goats were given a single intravenous (i.v.) injection of SAL (5 mg/kg body weight (BW)), a DA receptor antagonist (sulpiride, 0.1 mg/kg BW), or thyrotropin‐releasing hormone (TRH, 1 µg/kg BW) before and after treatment with a DA receptor agonist (bromocriptine), and the effect of DA on SAL‐induced PRL release was compared to that on sulpiride‐ or TRH‐induced release. Bromocriptine completely inhibited the SAL‐induced release of PRL (P < 0.05), and the area under the response curve (AUC) for a 120‐min period after the treatment with bromocriptine was 1/28 of that for before the treatment (P < 0.05). Bromocriptine also completely inhibited the sulpiride‐induced release (P < 0.05). The AUC post‐treatment was 1/17 that of pre‐treatment with bromocriptine (P < 0.05). Bromocriptine also inhibited the TRH‐induced release (P < 0.05), though not completely. The AUC post‐treatment was 1/3.8 that of pre‐treatment (P < 0.05). These results indicate that DA inhibits the SAL‐induced release of PRL in male goats, and suggest that SAL and DA are involved in regulating the secretion of PRL. They also suggest that in terms of the regulatory process for the secretion of PRL, SAL resembles sulpiride but differs from TRH.  相似文献   
56.
In this study, we examined the potential of Megasphaera elsdenii as a probiotic agent in combination with sodium gluconate. We also examined the combination of M. elsdenii with probiotic lactic acid bacteria (LAB), Lactobacillus acidophilus, to enhance butyrate production in the large intestine using a pig cecal in vitro model under the presence of sodium gluconate. Compared to the uninoculated control culture (with only diluted cecal digesta), the addition of M. elsdenii and LAB to the culture stimulated significantly the production of n‐butyrate (60% increase) and n‐valerate (50% increase) after 24 h incubation. n‐Butyrate is regarded as the most important short‐chain fatty acid in the large intestine because it stimulates the proliferation of epithelial cells, mucus release and water and mineral absorption. Therefore, lactate‐utilizing butyrate producers such as M. elsdenii play a significant role in supporting the health‐beneficial effects of lactogenic prebiotics and probiotics LAB. The potential of M. elsdenii as a probiotic was also suggested.  相似文献   
57.
The self-feeding abilities of individually reared rainbow trout Oncorhynchus mykiss were investigated under four different light intensities (7×10−2, 1×10°, 5×101, and 7×102 lx). There was no significant effect of light intensity on self-feeder learning ability and food wastage (which did not exceed 0.5%). However, there was high individual variability in the ability irrespective of light intensity. The total number of trigger actuations was significantly higher at 1×10° lx than at 7×10−2 and 5×101 lx. Feeding patterns during the light phase of a day were classified as early or late in relation to the timing of significant peaks in fish feeding, or non-steady. The last pattern was defined when significant peaks were not observed. Under 7×10−2, 1×10°, or 7×102 lx, a non-steady feeding pattern was the most common. Early feeding appeared only under the 1×10° lx regime with the random pattern, while the late pattern was observed under 7×10−2, 5×101, and 7×102 lx. Under 5×101 lx regime half of the fish fed in the afternoon. These results suggest that light intensity can affect the timing of feeding judged from the frequency of pulling bite tags, but does not affect waste or learning period.  相似文献   
58.
The effects of leptin on the release of luteinizing hormone (LH), growth hormone (GH) and prolactin (PRL) were studied in cultured bovine anterior pituitary (AP) cells in vitro. The AP cells were obtained from fully‐fed Japanese Black steers and were incubated for 3 h with 10?13 to 10?7 mol/L of leptin after incubating in Dulbecco's modified Eagle's Medium for 3 days. Leptin significantly increased the concentration of LH in the culture medium by 45 and 44% at doses of 10?8 and 10?7 mol/L, respectively, compared with the controls (P < 0.05). Leptin significantly increased the concentration of GH in the culture medium by 14 and 12% at doses of 10?8 and 10?7 mol/L, respectively (P < 0.05). Leptin also significantly increased the concentration of PRL in the culture medium by 26% compared with the controls at a dose of 10?7 mol/L (P < 0.05). These results show that leptin stimulates the release of LH, GH and PRL by acting directly on bovine AP cells from fully‐fed steers.  相似文献   
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