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231.
Renal allograft transplantation was performed in four beagles. Immunosuppressive treatment using cyclosporine, mizoribin and prednisolone was continued from Day 5 pre- until Day 20 post-transplantation. Between Days 28 and 32 post-transplantation, an abrupt elevation of the serum creatinine values followed by the development of uremia was seen in all recipients. Histopathology of the allografts examined between Days 28 and 37 revealed edema, necrosis, hemorrhage and severe diffuse interstitial cellular infiltration as well as tubulitis. Glomerular changes notably included swelling of the tufts due to hypercellularity, which was consistent with transplant glomerulitis. The intrarenal arteries exhibited fibrinoid necrosis of the walls and intimal or transmural cellular infiltration. These renal lesions were consistent with those of acute vascular and interstitial rejection in humans.  相似文献   
232.
In their quest for a blood meal, hematophagous arthropods must first defeat the host's hemostatic defense. Following injury as it occurs when hematophagous arthropods insert their proboscis into host skin to feed, the host will attempt to stop excessive blood loss through its hemostatic defense mechanism involving platelet aggregation, blood clotting and vasoconstriction. To acquire a full blood meal hematophagous arthropods inject an arsenal of bioactive enzymes which ultimately overpower the host's hemostatic defense. We have looked at a selected number of studies on the molecular biology of arthropod anti-hemostatic proteins and developed commentaries on the suitability of these molecules as target tick vaccine antigens.  相似文献   
233.
Immunological protection of hosts against tick infestation is at present the most practically sustainable alternative tick control method to the current use of acaricides that is riddled with serious limitations. The current focus of tick vaccine research is the identification, cloning and in vitro production of recombinant tick vaccine candidate antigens. We have examined a selected number of reports on the roles of parasite-encoded members of the serine proteinase inhibitor (serpin) superfamily in modulation of mammalian anti-parasite defense and developed some food for thought commentaries on the possibility of targeting this class of proteins for anti-tick vaccine development.  相似文献   
234.
Isoleucyl‐tRNA synthetase (IARS) c.235G > C (p.V79L) is a causative mutation for a recessive disease called IARS disorder in Japanese black cattle. The disease is involved in weak calf syndrome and is characterized by low birth weight, weakness and poor suckling. The gestation period is often slightly extended, implying that intrauterine growth is retarded. In a previous analysis of 2597 artificial insemination (AI) procedures, we suggested that the IARS mutation might contribute toward an increase in the incidence of prenatal death. In this study, we extended this analysis to better clarify the association between the IARS mutation and prenatal death. The IARS genotypes of 92 animals resulting from crosses between carrier (G/C) × G/C were 27 normal (G/G), 55 G/C and 10 affected animals (C/C) (expected numbers: 23, 46 and 23, respectively). Compared to the expected numbers, there were significantly fewer affected animals in this population (P < 0.05), suggesting that more than half of the affected embryos died prenatally. When the number of AI procedures examined was increased to 11 580, the frequency of re‐insemination after G/C × G/C insemination was significantly higher at 61‐140 days (P < 0.001). The findings suggested that the homozygous IARS mutation not only causes calf death, but also embryonic or fetal death.  相似文献   
235.
Murashige and Skoog medium (MS), woody plant medium (WPM), and a mixture of equal parts of MS and WPM (MW) were compared for in vitro shoot proliferation and rooting of four highbush blueberry (Vaccinium spp.) cultivars. During the multiplication stage, the shoots on WPM showed worse growth than the other shoots. The MW produced the best shoot growth. The shoots on MS grew well but tended toward hyperhydricity in the multiplication stage, especially in the case of ‘Bluecrop’ shoots. Rooting was worst in the shoots multiplied on WPM, while the best rooting percentage of ‘Bluecrop’ shoots was obtained on MS, and that of ‘O’Neal’ on MW. The rooted shoots developed a good root system and were easily acclimatized after potting.  相似文献   
236.
ORP150 is a hypoxic stress-induced protein located in the endoplasmic reticulum. Transgenic mice overexpressing ORP150 (ORP-Tg) exhibit vacuolar degeneration in the heart. To determine whether vacuolization is present in skeletal muscle, we pathologically examined ORP-Tg mice. After 60 days of age, severe vacuolization was found in the soleus muscles of the hind legs of the ORP-Tg mice. Immunohistochemical staining of ORP150 revealed co-localization of ORP150 and vacuolization in the affected cells. Electron microscopy revealed a marked increase in the number of rough-surfaced endoplasmic reticula (rER) and distention of the cisterna. These findings suggest that overexpression of ORP150 causes accumulation of ORP150 in the rER, resulting in vacuolar degeneration in the skeletal muscle of ORP-Tg mice.  相似文献   
237.
An 11-year-old male Golden Retriever presented with progressive weight loss, tachycardia, hyperthermia, polyuria and polydipsia. A freely movable mass, 4.5 x 4 cm in size, was palpated at the cranioventral cervical region. Hormonal study revealed high levels of serum thyroid hormones, and a tentative diagnosis of hyperthyroidism due to a thyroid tumor was made. The tumor was removed surgically and diagnosed histopathologically as thyroid gland adenoma. Serum thyroid hormone levels decreased after surgery with improved clinical signs. At 12 months after surgery, the dog maintained a good physical condition with no evidence of recurrence.  相似文献   
238.
The 'male effect' is a well-known phenomenon in female sheep and goats, whereby pheromone-induced activation of reproductive function occurs. In a previous study, we showed that the genes for elongation of long-chain fatty acids family member 5 (ELOVL5) and stearoyl-CoA desaturase 1 (SCD1) increased their expression significantly, concomitant with induction of pheromone synthesis. Therefore, these genes were considered to be prime candidate genes for pheromone synthesis. In the present study, we performed in situ hybridization to investigate where these two genes are expressed in goat skin. Strong positive signals were detected for both genes in the head skin of the male goat, which is the main site of pheromone production, and were mainly in the basal layer of the sebaceous gland cells, with the remaining cells showing negligible signals. None of the cells in the rump skin of the male goat or the head skin of the orchidectomized goat, neither of which produce pheromone, exhibited strong positive signals. The present study demonstrates that expression of these two candidate genes for pheromone synthesis is primarily localized in the sebaceous glands of the pheromone-producing skin region.  相似文献   
239.
Data from 19 Japanese Black multiparous cows were collected to clarify the relationships among immunoglobulin (Ig) G, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of cows in order to evaluate the role of fat‐soluble vitamins on colostral IgG and IgA production. Mean colostral IgG was 141 mg/mL, ranging from 65 to 208 mg/mL, whereas mean colostral IgA was 8.7 mg/mL, ranging from 1.0 to 34.6 mg/mL. Colostral IgG increased with aging in multiparous cows. There were positive correlations between colostral IgG and colostral vitamin A or colostral α‐tocopherol in cows, and the higher adjusted R2 was obtained in the prediction model of colostral IgG from age and colostral vitamin A. Colostral vitamin A was positively correlated with colostral β‐carotene or colostral α‐tocopherol in cows, but there were no relationships between colostral IgA and colostral IgG or colostral fat‐soluble vitamins. These results indicate that fat‐soluble vitamin contents in colostrum of cows may change in similar patterns and high colostral vitamin A is related with high colostral IgG.  相似文献   
240.
To study the immunomodulative activity caused by bovine leukemia virus envelope (BLV Env) peptide, sheep were immunized with two kinds of Th-epitope peptides, peptide 98 (BLV Env 98-117), and 61 (BLV Env 61-78). Four of eight immunized sheep showed specific proliferative responses against both of the peptide stimulations. To characterize the cells responding to the peptides, peptide-specific cells were established from the responding sheep by the continuous stimulation of peripheral blood mononuclear cells (PBMCs) with either peptide 98 or 61 in vitro. The peptide 98-specific cells consisted of CD4-positive cells, whereas the peptide 61-specific cells consisted of CD8-positive cells and MHC class II-positive cells. In addition, cytokine profile analysis indicated that the peptide 98-stimulated cells expressed IFN-gamma but not IL-10, although the peptide 61-stimulated cells expressed IL-10 but not IFN-gamma. These results show that BLV envelope peptides 98 and 61 can modulate immune responses of sheep lymphocytes in different ways and may contribute to the pathogenesis of BLV infection.  相似文献   
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