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101.
In a retrospective survey done from 1978-1988 in Japan, 32 male patients with ornithine transcarbamylase (OTC) deficiency were identified. We classified a neonatal and 2 late-onset groups, depending on clinical manifestations and the age at onset; group 1 (0-28 days; N = 10), group 2 (29 days-5 years; N = 13), and group 3 (greater than 5 years; N = 9). Compared to findings in the group 2 patients, there was a higher rate of mortality and a higher incidence of mental retardation in association with a great decrease in enzyme activity in group 1. In group 3, the mortality rate and enzyme activities were similar to those in group 1. However, patients in this group were asymptomatic prior to the first episode. Enzyme activities were measured mostly in autopsy samples. The serum citrulline levels (enzyme product) were highest in this group. Thus, the mutant enzymes were apparently labile with greater activities in vivo than in vitro. Treatments, including a protein-restricted diet, arginine supplementation, and sodium benzoate administration, resulted in a favorable prognosis for survivors with partial enzyme deficiency. We wish to emphasize that the incidence of late onset of this disease is higher than heretofore considered.  相似文献   
102.
The effect of intraluminal hypoxia on vascular tone and the release of prostaglandins (PG) I2 and E2 were investigated in intact isolated segments of canine femoral and coronary arteries as well as in the rat tail artery. Perfusion with hypoxic Tyrode's solution (pO2 20–40 mm Hg) evoked a marked vasodilation of the segments, precontracted with norepinephrine or serotonin. Simultaneously, a 2–3-fold increase in the release of 6-keto-PGF1 (the stable hydrolysis product of PGI2) could be observed. In parallel to 6-keto-PGF1, smaller quantities of PGE2 were released. Removal of the endothelium as well as pretreatment with indomethacin abolished both, the dilatory response and the PG-release. After administration of verapamil as well as 3,4,5-trimethoxybenzoic acid 8-diethyl-aminooctylester (TMB-8) (which binds intracellular calcium) the PG-increase was abolished and hypoxic dilatation could no longer be elicited, although the vessel had still a capacity to dilate. Exogenous administration of PGI2 and PGE2 showed that in canine femoral and coronary arteries PGI2 was the most effective vasodilating prostaglandin, while in the rat tail artery PGE2 had a 10-fold higher dilating potency compared to PGI2. At very high concentrations both PGI2 and PGE2 caused vasoconstriction. Our experiments suggest that the hypoxic endothelium-dependent dilatation may be mediated by an increased PG-release. Hypoxia-induced transmembrane calcium influx into the endothelial cells seems to be the trigger reaction.Supported by the Deutsche Forschungsgemeinschaft (Bu 436/2-1)  相似文献   
103.
1. Dorsal root ganglion (DRG) cells were dissected from the adult mouse with their peripheral nerves, and electrophysiological and morphological studies were performed. 2. The peripheral nerves were stimulateradish peroxidase (HRP) was injected into the cell body, and the size of stained cell body and axon, together with the state of myelination, were examined. 4. F-neurons, whose somatic spike is a tetrodotoxin (TTX)-sensitive Na spike, had a large or medium-sized cell body with a myelinated axon, and shoed a fast conduction velocity (A fibers). 5. A-neurons, whose somatic spike is a TTX-resistant Na spike, had a small cell body with an unmyelinated axon, and showed a slow conduction velocity (C fibers). 6. Most H-neurons, whose somatic spike is a TTX-resistant combined Na-Ca spike, proved to have conduction velocity and morphological features similar to A-neurons, whereas the rest of them had features similar to F-neurons. 7. A roughly linear correlation was exhibited between each pair of cell body size, axon diameter, and conduction velcoity. 8. Spike conduction along axons to cell bodies were blocked in all neurons either by an elimination of Na ions from the medium or by an application of TTX. 9. The possibility of transmission of different information by different DRG cells and the developmental differentiation of sensory neurons are discussed.  相似文献   
104.
T Sakamoto  K Ito  M Yamada  H Iguchi  M Ueda  Y Matsuda  S Torii 《Arerugī》1990,39(11):1492-1498
Recently large amounts of Aspergillus restrictus, a species of osmophilic fungi, have been detected in house dust using culture media with low water activity. But little attention has been paid to this fungus as an allergen. In the present study, the authors examined the allergenic activity of A. restrictus by skin prick tests and radioallergosorbent tests (RAST) on 94 asthmatic patients (mean age 12.0, range 3-18). Aspergillus fumigatus, Alternaria alternata and house dust were used for comparison. In the skin prick tests, A. restrictus, A. fumigatus, A. alternata and house dust elicited positive reactions in 8 (8.5%), 8 (8.5%), 15 (16.0%) and 69 (73.4%) patients, respectively. RAST showed positive reactions in 27 (28.7%) subjects for A. restrictus, 22 (23.4%) for A. fumigatus, 35 (37.2%) for A. alternata, and 75 (79.8%) for house dust. These results indicated that some asthmatic individuals showed immediate-type hypersensitivity to A. restrictus, and the prevalence of hypersensitivity of A. restrictus determined by skin prick tests and RAST was comparable with that of A. fumigatus but lower than that of A. alternata or house dust. This indicates that this fungal species may be of importance as a causative agent in atopic diseases.  相似文献   
105.
In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that VH-D and D-JH recombination took place in a single allele. Both VH-D and D-JH complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a VH-D(-D)-JH formation. With this finding, we propose a novel pathway, in which the VH-D complex is an intermediate in the formation of a functional VH exon.  相似文献   
106.
The aim of the present study was to evaluate levels of soluble CD 163 in sera and fluids from rheumatoid arthritis (RA) patients and elucidate the mechanism that regulates the shedding of CD163. Levels of soluble CD163 in sera and fluids from RA patients were examined by a sandwich enzyme immunoassay and Western blotting. To determine the effects of tissue inhibitors of metalloproteinase (TIMPs) on the shedding of CD163 from monocytes/macrophages, levels of soluble CD163 in cultures of monocytes/macrophages and the expression of CD163 on monocytes/macrophages in the presence or absence of TIMPs were examined by a sandwich enzyme immunoassay and flow cytometry, respectively. The clinical marker that was most associated with serum levels of soluble CD163 was levels of CRP. TIMP-3, but not TIMP-1 or TIMP-2, inhibited the shedding of CD163 from monocytes/macrophages. It was shown that serum levels of soluble CD163 are a sensitive and reliable marker to monitor activated macrophages in synovitis from RA patients and the results imply that the responsible proteinase for the shedding of CD163 is not a member of the matrix metalloproteinases, but is likely to be a member of ADAMs.  相似文献   
107.
Motoneurons innervating the posterior belly of the digastric muscle were identified in the monkey, cat, dog, guinea pig and rat by the HRP method. After injections of horseradish peroxidase (HRP) into the posterior belly of the digastric muscle, two groups of HRP-labeled motoneurons were observed; the rostral group was seen as a small cluster of neurons in the lateral reticular area along the medial border of the descending root of the facial nerve, and the neurons of the caudal group were distributed among the ascending root fibers of the facial nerve. The distribution pattern of these neurons corresponded to that of the accessory facial nucleus neurons. The accessory facial nucleus was lacking in the rabbit in which the posterior digastric (PD) muscle is nonexistent.  相似文献   
108.
An autopsy case of a 74-year-old male who had shown clinically hypothyroidism due to chronic atrophic thyroiditis (Hashimoto's thyroiditis), and pathologically necrotizing myopathy as a remote effect of gastric cancer was reported.
Morphological features of this necrotizing myopathy was those of carcinomatous myopathy rather than those of hypothyroid or diabetic myopathy.
As for the pathogenesis of the necrotizing myopathy (as a Group IV of polymyositis of Walton and Adams), the malignancy might have played an important role as a trigger of the secondary immunological abnormality upon a pre-exizting longstanding immune disorder of Hashimoto's thyroiditis. Pseudomembranous colitis, which was thought to be related to antibiotics (Lincomycin), was also briefly discussed.  相似文献   
109.
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