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91.
Inhibition ELISA assay was used to examine the cross-reaction of the polyclonal anti-desmosine antiserum produced in rabbit against molecules possessing a "pyridinium ring" as their core structure i.e. isodesmosine, pentasine, pyridinoline and 2'-deoxypyridinoline, highly purified with column chromatography, and structurally unrelated substances, i.e. cysteic acid, taurine and 2-aminopyridine (core structure of desmosine). No cross-reaction was observed to the pyridinoline, 2'-deoxypyridinoline possessing "pyridinium ring" and derived from collagen cross-links, structurally unrelated cysteic acid and taurine, nor core structure of 2-aminopyridine. The antiserum specifically recognized the molecules derived from the elastin cross-links. Using the ELISA assay system with antisera and amino acids analysis, 10 micrograms of desmosine were extracted from 1.0 mg of the hydrolysate of commercial elastin.  相似文献   
92.
It is known that benzodiazepines have a hypotensive effect, but the mechanism has not been well elucidated yet. To clarify whether this effect is due to central or peripheral mechanism, we administered 5 mg of diazepam or saline intravenously to healthy volunteers and assessed the change in blood pressure, heart rate, muscle sympathetic nerve activity and heart rate variability. After diazepam administration, systolic and mean blood pressure decreased significantly. Muscle sympathetic nerve activity was also significantly reduced but heart rate did not change, whereas the variables of spectral analysis of heart rate variability did not show significant change. We concluded that the hypotensive effect of diazepam in human is mainly due to the central mechanism.  相似文献   
93.
 The recently identified prostate cancer susceptibility gene ELAC2 (HPC2) harbors two common missense variants, a serine to leucine substitution at residue 217 (Leu217) and an alanine to threonine substitution at residue 541 (Thr541). We genotyped the two variants in a Japanese cohort consisting of 350 prostate cancer patients 242 male population controls, and 114 male low-risk controls. Both missense alleles, Leu217 and Thr541, were carried at higher frequency in Japanese patients than in the controls (Leu217, P = 0.0012; Thr541, P = 0.0145), and the odds ratios associated with carrying these sequence variants were higher in Japanese than in Caucasians. Although the Leu217 and Thr541 variants of ELAC2 are less common in Japanese than in Caucasians, both variants confer significantly increased risk of prostate cancer in Japanese. Carriage of these variants was not associated with age at diagnosis, tumor stage, or tumor grade in these Japanese prostate cancer patients. The allele-specific pattern of risk observed in Japanese and familial Caucasian patients was qualitatively similar; however, the magnitude of that risk was considerably greater in Japanese than in Caucasians. Received: September 3, 2002 / Accepted: October 2, 2002  相似文献   
94.
95.
An implantable secondary battery is one of the key components in a total artificial heart system. Because a 2 year cycle life is required, the cycle life of the secondary battery as well as its charge and discharge properties are important parameters for selection of an appropriate battery. We carried out cycle life tests on four kinds of rechargeable batteries (a Ni-MH secondary battery, a Ni-Cd secondary battery, a Li-ion battery with a graphite anode, and a Li-ion battery with a nongraphitizable carbon electrode) to determine their suitability as implanted back-up batteries. Each of the batteries was charge/discharge cycled at 37 degrees C to 39 degrees C using a charge current of 1 C ampere, and they were each fully discharged under either pulsatile discharge loads, which mimicked pulsatile operation, or a nonpulsatile load equivalent to the average of the pulsatile loads. The two Li-ion batteries made by different manufacturers both met the minimum requirement of cycle life of more than 1,500 cycles, considering safety coefficient regardless of the discharge pattern. In addition, the temperature increase of these Li-ion batteries (3 degrees C) was lower than that of Ni-Cd and Ni-MH batteries (15-25 degrees C). Out of these four batteries, the two Li-ion batteries are the most suitable for use in a totally implantable artificial heart system.  相似文献   
96.
97.
Stimulation of resistance to infection induced by the analogs of muramyl dipeptide (MDP) having substituted functions in the gamma-carboxyl group of D-isoglutamyl residue was examined in experimental Escherichia coli infections in mice. An MDP analog which is an efficient strengthener of resistance to infection, N alpha-MDP-N epsilon-stearoyllysine [MDP-Lys(L18)], was selected through the comparative assessment of a number of compounds in three categories: (i) gamma-alkylamides, (ii) gamma-esters, and (iii) N alpha-MDP-N epsilon-acyllysine derivatives. Furthermore, the antiinfectious activity of MDP-Lys(L18) was evaluated bacteriologically in comparison with that of MDP. The effect of MDP-Lys(L18) on the susceptibility of mice to infections with various species of microorganisms was studied. Protective activity was greatest against E. coli and staphylococcal infections, considerable against Pseudomonas and Candida infections, and least against Klebsiella infection. The effects of bacterial inoculum size and MDP treatment timing, dose, and route of administration on protective activity were studied. The efficacy of MDP-Lys(L18) in protection tests was demonstrated for all administration routes, even the oral. Its high potency was confirmed by the smaller influence of inoculum size and particularly small value of the minimum dosage required for inducing protective activity. A decrease in bacterial survival was observed in the blood and organs of mice treated with the analog and infected with E. coli. The following two useful effects were obtained: the synergistic effect of glycopeptide and chemotherapeutic agents and the stimulation of resistance to infection in animals immunocompromised by cyclophosphamide treatment.  相似文献   
98.
Rabbits were intravenously inoculated with an attenuated rinderpest virus (L strain), and general patterns of the disease were investigated. The rabbits developed fever with concomitant occurrence of diarrhea and lymphopenia. Early production of interferon was followed by a rise of neutralizing antibody. Histological examinations revealed an involvement of all of the lymphoid tissues, with primary lesions consisting of necrosis of the lymphoid follicles and formation of giant cells. Immunofluorescent examinations suggested that the virus growth was present in almost all of the lymphoid tissues. The possibility of application of this experimental system for the study of systemic infection by measles virus was discussed.  相似文献   
99.
Background: The presence of efferent fibers in the anteromedial eye of liphistiid spiders kept in natural daily cycles of illuminance has been reported. However, this report is limited to innervation by the efferent fiber and daily rhabdomal changes, and there have been no detailed ultrastructural accounts of the eye. Methods: The fine structure of this eye was examined by electron microscopy. Results and conclusions: The eye consists of a cornea, a lens, a vitreous body, and a retina. The retina contains 13 or 14 receptor cells and glial cells. The rhabdoms are distal to the nuclei of the receptor cells. In the distal region of the receptive segment, the rhabdomeres lie in the center of the cell. In the middle region, anisomorphic rhabdoms formed by microvilli from adjacent cells are at the cell periphery. In the proximal region, the rhabdomeres are situated in the center of the cell. The ocellar nerve of the eye runs toward the protocerebrum and enters the posterior part of the first optic ganglion of the secondary eyes. Pigmented cells and nonpigmented cells are observed. The pigmented cells are located in the most lateral of the eye and cover the whole eye. The nonpigmented cells are located in the receptor cell bodies and extend to the origin of the ocellar nerve. They wind to form capillaries filled with electron-dense material. These structures are discussed in comparison with those of other spiders and other chelicerates. © 1994 Wiley-Liss, Inc.  相似文献   
100.
It has been widely accepted that hematopoietic and endothelial cell lineages diverge from a common progenitor referred to as the hemangioblast. Recently, analyses of the potential of progenitor cells purified from mouse embryos as well as embryonic stem cells differentiating in vitro resolved intermediate stages between mesodermal cells and committed precursors for hematopoietic and endothelial cell lineages. There are two distinct hematopoietic cell lineages which have different origins, i.e., primitive hematopoietic lineage derived from mesoderm or hemangioblasts and definitive hematopoietic lineage derived from endothelial cells. The endothelium is suggested to provide a milieu in which the definitive hematopoietic lineage acquires multiple potentials.  相似文献   
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