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61.
Plant architecture plays an important role in the yield, product quality, and cultivation practices of many crops. Branching pattern is one of the most important components in the plant architecture of melon (Cucumis melo L.). ‘Melon Chukanbohon Nou 4 Go’ (Nou-4) has a short-lateral-branching trait derived from a weedy melon, LB-1. This trait is reported to be controlled by a single recessive or incompletely dominant major gene called short lateral branching (slb). To find molecular markers for marker-assisted selection of this gene, we first constructed a linkage map using 94 F2 plants derived from a cross between Nou-4 and ‘Earl’s Favourite (Harukei-3)’, a cultivar with normal branching. We then conducted quantitative trait locus (QTL) analysis and identified two loci for short lateral branching. A major QTL in linkage group (LG) XI, at which the Nou-4 allele is associated with short lateral branching, explained 50.9 % of the phenotypic variance, with a LOD score of 12.5. We suggest that this QTL corresponds to slb because of the magnitude of its effect. Another minor QTL in LG III, at which the Harukei-3 allele is associated with short lateral branching, explained 9.9 % of the phenotypic variance, with a LOD score of 4.2. Using an independent population, we demonstrated that an SSR marker linked to the QTL in LG XI (slb) could be used to select for short lateral branching. This is the first report of mapping a gene regulating the plant architecture of melon.  相似文献   
62.
An atovaquone (ATV)-resistant Babesia gibsoni was developed by in vitro exposure of uncloned wild type (WT) B. gibsoni to 800 nM ATV for 6 days. Sequence analysis of mitochondrial genes showed a single-nucleotide polymorphism (SNP) at cytb nt363 (G to T) that resulted in the substitution of methionine with isoleucine (M121I), which is one of the SNPs reported in a previous in vivo study. 363T or 363G allele-specific real-time polymerase chain reaction (PCR) revealed that an M121I variant was present in over 99% of the ATV-resistant population. As neither ATV resistance nor gene polymorphisms appeared in the B. gibsoni WT sibling clones, the expression of ATV resistance in this study was suspected to be because of selective multiplication of the B. gibsoni M121I variant. This ATV-resistant B. gibsoni displayed the same sensitivity as the WT B. gibsoni against 5 other drugs, including diminazene aceturate, azithromycin, doxycycline, clindamycin, and proguanil. This is the first report on the in vitro establishment of an ATV-resistant B. gibsoni with gene polymorphisms.  相似文献   
63.
Acquired arachnoid cyst in a cat   总被引:1,自引:1,他引:0  
A 5-year-old Birman cat presented with paraparesis associated with a fracture of the third thoracic vertebra and was managed conservatively. Voluntary function was regained over the next 6 months, but the cat was referred 4 years after the trauma because of recurrence of hindlimb paresis and ataxia. Magnetic resonance imaging (MRI) showed a spinal arachnoid cyst at the level of the fourth thoracic vertebra, which was treated surgically by dorsal laminectomy and durectomy, and hindlimb function subsequently recovered. The cat re-presented 4 years later for recurrent hindlimb paresis. Myelography and computed tomography–myelography (CT-M) showed dorsolateral pooling of cerebrospinal fluid (CSF) at the previous laminectomy site. The neurological signs after the second surgery improved, but not as much as after the first surgery and the cat remained ataxic with moderate paresis. Seven months later repeat CT-M revealed an atrophic spinal cord, but negligible pooling of CSF at the previous site of the arachnoid cyst. The cat could walk, but was being treated for self-induced trauma of the left hindlimb that was thought to be related to paraesthesia. The neurological signs gradually deteriorated over 3 months and the cat was euthanased.  相似文献   
64.
Diffuse global granulomatous glomerulonephritis with unique morphological characters was detected in a pig. The structure of the basement membrane of glomerular tufts was destroyed in almost all glomeruli. Various inflammatory cells consisted mainly of macrophages infiltrated severely into the glomerular tuft and the Bowman's space of and extended to the periglomerular interstitium. Periarteritis with fibrinoid necrosis was occasionally seen in the arterioles and small arteries running through the renal parenchyma and pelvis. In the present case, the results of either the immunohistochemical reactions to the antigens against PRRSV or PCV-2 or Ziel-Neelsen staining for acid-fast bacilli were negative and no pathogenic bacteria were cultured.  相似文献   
65.
A deformed liver characterized by remarkable ductular proliferation was encountered in a 6-month-old pig and examined histopathologically. The most conspicuous histopathologic change was a mild to severe ductular proliferation in the interlobular areas without any degenerative changes of cholangiolar epithelial cells or hepatocytes. Fibrotic changes and reconstruction of the lobule were not found. Morphological evidence of intrahepatic and extrahepatic cholestasis was lacking. Other characteristics were deformity with displacement of the gall bladder, irregular shape and size of lobules, and structural abnormality of large-sized vessels. The severe ductular proliferation was considered to be due to structural malformations of the excretion channel of bile.  相似文献   
66.
Eight periparturient Holstein Friesian cows were examined for plasma tartrate-resistant acid phosphatase (TRAP) activity to assess the degree of bone metabolic activity and to evaluate the association between the change in calcium (Ca) concentration and bone metabolism during the periparturient period. Milk fever occurred in 1 of 8 cows just after parturition. Plasma TRAP activities did not markedly change in 5 of 8 cows during the experimental period. The changing rate of Ca between preparturition and just after parturition was under -20% in 3 of 8 cows, and low TRAP activities were observed in 2 of these 3 cows. This study suggests that cows with a low TRAP activity are at risk of developing milk fever in comparison to cows with high TRAP activity. Temporary increases of parathyroid hormone were observed in 7 cows, but not in the cow with milk fever.  相似文献   
67.
To investigate flower induction in June-bearing strawberry plants, morphological changes in shoot apices and Histone H4 expression in the central zone during flower initiation were observed. Strawberry plants were placed under flower inducible, short-day conditions (23 °C/17 °C, 10 h day length) for differing number of days (8, 16, 20, 24 or 32 days) and then these plants were transferred to non-inducible, long-day conditions (25 °C/20 °C, 14 h day length). The shoot apices of plants placed under short-day conditions for 8 days were flat, similar to shoot apices of plants in the vegetative phase of development, and Histone H4 was not expressed in the central zone during the experimental period. On the other hand, the shoot apices of plants placed under short-day conditions for 16 days remained flat, similar to shoot apices of plants placed under short-day conditions for 8 days, but Histone H4 was expressed in the central zone at the end of the short-day treatment. Morphological changes in the shoot apices of these plants were observed 8 days after the change in day-length. These plants developed differentiated flower organs after they were grown for another 30 days under long-day conditions. These results indicate that changes in the expression pattern of the Histone H4 gene occur before morphological changes during flower induction and that the expression of the gene in the central zone can be used as one of the indicators of the flowering process in strawberries.  相似文献   
68.
A transient increase in apoptotic polymorphonuclear neutrophils (PMNs) as revealed by the terminal deoxynucleotidyl, transferase-mediated dUTP nick end labeling (TUNEL) technique in bovine jugular and milk vein blood was observed 4 h after intramammary infusion of Escherichia coli lipopolysaccharide (LPS) (jugular vein; before infusion 10.1%, 4h 58.3%: milk vein; before infusion 13.2%, 4 h 76.6%) decrease in PMA-induced oxidative bursts of PMNs was also observed during the same period and continued until 8 h after the infusion. TUNEL-positive cells showed an intention of a Comet tail as detected by a single-cell gel electrophoresis assay (Comet assay) and the morphological apoptotic future, though DNA fragmentation was not clearly detected. A definite decrease in peripheral PMNs and a marked increase in PMNs in the LPS-infused teat cistern were observed during the same period. The migration of milk vein blood-derived PMN and the expression of adhesion receptors (L-selectin and CD18) on PMN were suppressed, accompanied by an increase in apoptotic cells. TUNEL-positive PMN observed in normal animals showed a reduced migration capacity. The increase in apoptotic PMNs observed in the LPS-infused cattle was thought to be due to the remaining intravenous spontaneous apoptotic cells existing under the normal condition (the aging cell), and this increase appeared to lower the expression of adhesion receptors and the migration capacity. Decreased PMA-induced oxidative burst activity in PMN was thought to be derived from these aging cells and immature band cells appearing in the circulation as a subsequent event of leukopenia and/or severe stress associated with mastitis. The results from the present study indicate the possibility that the function of PMN in the circulation at early stages of bovine mastitis is regulated by the kinetics of PMN aging.  相似文献   
69.
A 10-year-old Golden Retriever dog had a solitary tumor mass arising from the greater omentum. Histologically, the tumor showed varying cellularity and patterns of cellular arrangement. In dense cellular areas, spindle-shaped cells were arranged in interlacing bundles. The sparse cellular area was characterized by loosely arranged fusiform cells. The neoplastic cells frequently contained PAS-positive eosinophilic globules in the cytoplasm, and mitotic figures were frequently observed. The tumor cells were positive to vimentin, S-100 protein, glial fibrillary acidic protein, myelin basic protein, neuron-specific enolase and myoglobin. The present tumor was diagnosed as a malignant peripheral nerve sheath tumor (MPNST) with eosinophilic cytoplasmic globules arising from the greater omentum. To our knowledge, this may be the first case of primary omental MPNST in domestic animals.  相似文献   
70.
The transportation of intravenously administered bovine lactoferrin (bLF) into the cerebrospinal fluid (CSF) was immunohistochemically investigated in adult rats. Administered bLF was detected in the vesicular membranes of endothelial cells in cerebral blood vessels 10 min after the infusion. Numerous immunoreactive small vesicles were also detected at the ependymal cells in the choroid plexus. Moreover, the bLF concentration in the CSF was significantly increased at 1-2 hr after the intravenous infusion of bLF (10 or 30 mg/kg). These findings clearly demonstrate that LF is possibly transported into the brain matter even in adult animals.  相似文献   
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