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101.
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   
102.
 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   
103.
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105.
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   
106.
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   
107.
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   
108.
We established two different IL-5-dependent Ly1+ early B cell lines in long-term bone marrow culture system. One of them (J-87) is stromal cell (ST2) dependent and the other (T-88) is ST2 independent. Both J-87 and T-88 are B220+, Ly1+, sIgM-, Ia-, Thy1-, and IL-2R+, and respond to IL-3 and IL-5 in the presence of ST2. The T-88 can proliferate only in response to IL-5 in the absence of ST2. Southern blot analysis using JH probe revealed that configuration of IgH gene of both cell lines shows rearranged pattern. Binding assay for radiolabeled IL-5 to T-88 demonstrated that T-88 has two classes of IL-5 binding sites (low and high affinity) on the membrane. These data strongly suggest that there are IL-5-sensitive stages at both stromal cell-dependent and stromal cell-independent phases in early B cell development.  相似文献   
109.
Relationship between SIRS and CARS in the pathologic condition of acute pancreatitis was discussed. SIRS promotes excessive inflammatory reaction and CARS induces the susceptibility to infection. Both conditions can develop into organ failure in acute pancreatitis. Hence, countermeasures for both conditions are mandatory in the care of patients with acute pancreatitis.  相似文献   
110.
BACKGROUND: The essential role of Th cells and T cell cytokines in eosinophilic inflammation has been established. METHODS: To determine whether Th cells are sufficient for the development of airway eosinophilic inflammation, ovalbumin-reactive murine Th clones were established and infused into unprimed mice. RESULTS: Eosinophilic infiltration into the lung was induced upon antigen inhalation in parallel with the rise in bronchoalveolar lavage fluid (BALF) eosinophil peroxidase activity. Neither IgG, IgA, nor IgE antibodies were present in this model. Pathological examination showed swelling and desquamation of epithelial cells, mucous plugs, and goblet cell hyperplasia, all of which well resemble human asthma. Fluorescent probe labeled Th clones migrated into the lung prior to the eosinophil accumulation. Bronchial hyperresponsiveness (BHR) was clearly induced upon antigen inhalation. Anti-IL-5 monoclonal antibody abrogated the responses. Dexamethasone and cyclosporin A suppressed cytokine production by Th cells both in vitro and in vivo, BALF eosinophilia, and BHR. The number of eosinophils recovered in the BALF correlated with the intensity of BHR. CONCLUSION: The results clearly indicated that monoclonal Th cells are sufficient for the development of both airway eosinophilia and BHR. Agents capable of downregulating IL-5 production seem promising for the treatment of bronchial asthma.  相似文献   
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