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361.
The osteological development of the feeding apparatus was examined in early stage larvae of laboratory-reared seabass,Lates calcarifer. At initial mouth openings 40 hours after hatching, the larvae were equipped with the fundamental elements forming the oral cavity, such as the trabecular roof, the lower branchial and hyoid arches forming the floor, the quadrate and symplectic-hyomandibular cartilages making up the sides, and the maxilla and Meckel's cartilage bordering the jaws. The cleithrum appeared almost simultaneously. The mechanics of creating a negative pressure in the oral cavity, which results in a “sucking” mode of feeding, were elucidated from these elements. During a period from 50–60 to 100–110 hours after initial mouth opening (HAMO), new elements such as the premaxilla and jaw teeth appeared, and the ossification of existing elements started. The new elements apparently enabled the larvae to “grasp” food organisms, in addition to the already existing and increasing sucking ability, from 100–110 HAMO.  相似文献   
362.
Bovine casein components (αsl-, β-, and κ-caseins) were chemically phosphorylated and the properties of the modified components were compared with those of the native to clarify the function of the intrinsic phosphate groups of casein components in casein micelle formation. The calcium binding ability of casein components increased after chemical phosphorylation. The concentrations of calcium chloride required to precipitate modified αsl- and β-caseins were higher than those for native components. However, phosphorylation of αsl- and β-caseins did not affect their properties of forming micelles through interaction with κ-casein. The stabilizing ability of κ-casein for αsl- and β caseins was impaired by its phosphorylation, but the stability was recovered by treating phosphorylated κ-casein with phosphoprotein phosphatase. The results show that the phosphate content of κ-casein must be low to form a stable casein micelle. The results also explain why the specific phosphorylation of casein components in the mammary gland is required.  相似文献   
363.
Transection of a peripheral nerve in neonatal rats induces death of the axotomized neurons which may be due to either necrosis or apoptosis. In the present investigation, neuronal cell death in L5 dorsal root ganglion was evaluated after unilateral sciatic nerve transection in rats at 1, 3, 5, 7 and 10 days age. After 5 days, right (experimental) and left (control) dorsal root ganglia in all groups were removed, fixed, processed and embedded for either light or electron microscopy. Normal nucleoli were counted in paraffin embedded serial sections, and correction factors for split and multiple nucleoli were applied as well as the physical disector. The number of neurons in the right dorsal root ganglia, as compared with the controls, was significantly lower in all groups, and the percentage of the reduction at 1, 3, 5, 7 and 10 days was 32.4, 27.2, 23.8, 22.8 and 21.8% respectively. On the other hand, the results of neuronal counts using the disector method showed 34.0, 25.7, 20.2, 20.0 and 14.2% reduction in the number of neurons at 1, 3, 5, 7 and 10 days, respectively. The microscopic and ultrastructural results indicated that there were typical morphological changes similar to those of apoptosis, including condensed basophilic nuclei, formation of nuclear caps, cell shrinkage and apoptotic body formation. We concluded that there is an increase in apoptosis in dorsal root ganglia following sciatic nerve axotomy with the greatest neuronal loss on postnatal day 1.  相似文献   
364.
365.
We developed an easy enzyme-linked immunosorbent assay (ELISA) for anti-mitochondrial antibodies, and detected high levels of anti-mitochondrial antibodies in MRL/Mp-lpr/lpr (MRL1/l) mice. The influence of the presence of anti-DNA antibodies in the tested sera on this assay was also evaluated. The monoclonal anti-DNA antibodies, which were made from non-immunized MRL1/l mice, did not react with the mitochondrial antigens adhering to polystyrene plates. Absorption with DNA had little effect on the levels of mitochondrial antibodies in MRL1/l sera. Our assay for mitochondria-binding antibody was very easy and sensitive, although it could not differentiate among heterogeneous anti-mitochondrial antibodies.  相似文献   
366.
Cognitive deficits have been observed in patients with multiple sclerosis (MS) due to hippocampal insults. Antioxidant vitamins D and E are suggested for patients suffering from neurodegenerative diseases like MS, while their mechanisms of action are not well understood. Here, we have tried to study the effects of these vitamins on demyelination, cell death, and remyelination of rat hippocampus following local ethidium bromide (EB) injection. Animals received 100 mg/kg vitamin E or 5 μg/kg of vitamin D3 for 2, 7, or 28 days. The extent of demyelination, myelin staining intensity, and expression of myelin basic protein and caspase-3 were investigated using histological and immunoblotting verification. Administration of EB alone caused demyelination, cell death, and afterward an endogenous repair. Vitamins E and D3 reduced the EB-induced damage and increased the endogenous remyelination of hippocampus. Although the anti-apoptotic effect of these vitamins and protection against demyelination were predictable based on their antioxidant effect, our results indicated the positive effect of vitamins E and D3 on process of remyelination by endogenous progenitor cells and supported their possible therapeutic effects in the context of demyelinating diseases like MS.  相似文献   
367.
A new method for purification of anti-glycosphingolipid antibodies had been developed. N-Glycolylneuraminyl(alpha 2-3)lactosylceramide [hematoside (NeuGc)] could be hydrophobically bound on octyl-Sepharose 4B in the presence of 0.1 M KCl. The Sepharose gel coated with hematoside (NeuGc) was used as immunoadsorbent for affinity column chromatography to purify avian anti-hematoside (NeuGc) antibody. The procedure is very simple, reproducible and applicable to purification of almost all anti-glycosphingolipid antibodies. The glycosphingolipid used for the affinity chromatography could be recovered without any destruction by successive extraction of the gel with methanol and methanol/chloroform (1:2, v/v).  相似文献   
368.
A synthetic peptide bearing a lanthanide complex, TbOTZ exhibits a decrease of chromophore fluorescence and a concomitant luminescence enhancement due to sensitized Tb3+ upon Zn2+ binding. Thus, TbOTZ can be a valuable tool for ratiometric sensing of Zn2+ as well as for time-resolved fluorescence detection with a single molecule.  相似文献   
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