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21.
Kidneys of 64 Afghan pikas (Ochotona rufescens rufescens) were examined histologically. Seven of 21 males and two of 21 females over 6 months of age had a cuboidal epithelium lining of the parietal layer of Bowman's capsule. 相似文献
22.
T Ishida Y Kumagai Y Ikeda K Ito M Yano S Toki K Mihashi T Fujioka Y Iwase S Hachiyama 《Drug metabolism and disposition》1989,17(1):77-81
A novel glutathione-conjugated metabolite of morphine has been isolated from the bile of guinea pigs given morphine. The metabolite was separated by preparative HPLC on a reverse phase column (YMC-GEL C18) using methanol/water (1:4, v/v) as eluate and purified by HPLC on another reverse phase column (mu-Bondapak phenyl) using water/acetonitrile/trimethylamine/acetic acid (150:3:2:1, v/v) as a mobile phase. The unambiguous structure assignment of the metabolite was performed by fast atom bombardment mass spectrometry and 400 MHz fourier transform NMR spectrometric analysis, and it was identified as (8S)-glutathion-S-yl)dihydromorphinone, in comparison with the synthetic morphinone-glutathione adduct. 相似文献
23.
Satoshi Kuwabara Nobuhiro Yuki Michiaki Koga Takamichi Hattori Daisuke Matsuura Masami Miyake Masatoshi Noda 《Annals of neurology》1998,44(2):202-208
To investigate the pathophysiological role of anti-GM1 antibody in Gullain-Barre syndrome (GBS), we reviewed sequential nerve conduction studies of 345 nerves in 34 GBS patients. Statistically significant correlation between IgG anti-GM1 antibodies and electrodiagnoses was found. Sixteen IgG anti-GM1-positive patients were classified as having acute motor sensory axonal neuropathy (AMAN or AMSAN) (12 patients), as having acute inflammatory demyelinating polyneuropathy (AIDP) (3 patientsrpar;, or as undetermined (1 patient) by electrodiagnostic criteria. Besides axonal features, there was rapid resolution of conduction slowing and block. In 3 patients initially diagnosed as having AIDP, conduction slowing was resolved within days, and 1 of them and 3 AMAN patients showed markedly rapid increases in amplitudes of distal compound muscle action potentials that were not accompanied by prolonged duration and polyphasia. The time courses of conduction abnormalities were distinct from those in IgG anti-GM1-negative AIDP patients. Rapid resolution of conduction slowing and block, and the absence of remyelinating slow components, suggest that conduction failure may be caused by impaired physiological conduction at the nodes of Ranvier. Reversible conduction failure as well as axonal degeneration constitutes the pathopsiological mechanisms in IgG anti-GM1)positive GBS. In both cases, immune-mediated attack probably occurs on the axolemma of motor fibers. 相似文献
24.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis
of microscopic and macroscopic findings postembolization.
Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients
who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the
basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding
type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings:
single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth
type.
Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing
type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis)
to the SNE type (21%), and the other types (9%). 相似文献
25.
Masami Hamaguchi Takaharu Ishibashi Naoki Katsumata Akio Mitomi Shoichi Imai 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1992,6(6):611-622
Summary In beagle dogs anesthetized with enfluranenitrous oxide, effects of sodium nitroprusside (SNP; MR7S1) and nitroglycerin (NTG) on hemodynamics and main organ circulation were studied to evaluate their effectiveness and safety as hypotensive agents during anesthesia. SNP (MR7S1) infusion (1–10 g/kg/min) decreased arterial blood pressure in a dose-dependent manner. The hypotension was stable during the infusion. After discontinuation of infusion, the blood pressure rapidly returned to the initial level. The hypotension was associated with decreases in cardiac output and total peripheral resistance. NTG infusion (3–10 g/kg/min) decreased arterial blood pressure, too, but the hypotension was less marked and not dose dependent, and the recovery was slower. Neither drug changed the heart rate. Infusion of SNP (MR7S1) and NTG did not change the hypotension induced by the injection of adenosine, SNP, and NTG. Furthermore, cerebral blood flow, cerebral oxygen consumption, and renal blood flow were unchanged during the hypotension produced by either drug. Coronary blood flow was decreased, but this was due to decreases in cardiac oxygen consumption. In conclusion, SNP (MR7S1) is superior to NTG as a hypotensive agent during anesthesia in efficacy, clear dose dependency, and rapid recovery. The hypotension induced by NTG as well as SNP (MR7S1) seems to have no undesirable effects on the circulation of important organs. 相似文献
26.
Rapid serodiagnosis of active pulmonary Mycobacterium tuberculosis by analysis of results from multiple antigen-specific tests 总被引:5,自引:0,他引:5
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Okuda Y Maekura R Hirotani A Kitada S Yoshimura K Hiraga T Yamamoto Y Itou M Ogura T Ogihara T 《Journal of clinical microbiology》2004,42(3):1136-1141
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis. 相似文献
27.
Active matrix metalloproteinases in the tear fluid of individuals with vernal keratoconjunctivitis 总被引:3,自引:0,他引:3
Kumagai N Yamamoto K Fukuda K Nakamura Y Fujitsu Y Nuno Y Nishida T 《The Journal of allergy and clinical immunology》2002,110(3):489-491
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC. 相似文献
28.
Polycystic ovarian syndrome was induced in adult rats by treatment with continuous illumination to study follicular atresia.
Granulosa cells of regressing antral follicles showed characteristic features of apoptosis ultrastructurally: condensed nuclei,
apoptotic bodies, and phagocytosis of the apoptotic cells and their fragments by neighboring cells. In this study, moreover,
it was observed that an intact granulosa cell was able to ingest another granulosa cell of normal appearance, presumably indicating
an early stage of follicular atresia. The phagocytosing granulosa cell surrounded another granulosa cell to be phagocytosed
by elongated cell processes. Gap junctions developed between the phagocytic cell and the phagocytosed cell. The phagocytic
cell possessed abundant free ribosomes, well-developed rough endoplasmic reticulum and mitochondria, but few lysosomes. The
ingested cell was similar in appearance to the phagocytic cell. In addition, granulosa cells were also observed ingesting
karyopyknotic cells and degenerative organelles, both displayed in large vacuoles filled with fragments of nuclei and organelles.
These findings suggest a process of apoptosis in the granulosa cells during follicular atresia.
This study was presented at the 20th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Fukuoka, September
1–3, 1988. 相似文献
29.
Molecular mechanism for connective tissue destruction by dipeptidyl aminopeptidase IV produced by the periodontal pathogen Porphyromonas gingivalis 总被引:3,自引:0,他引:3
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Porphyromonas gingivalis is a pathogen associated with adult periodontitis. It produces dipeptidyl aminopeptidase IV (DPPIV), which may act as a virulence factor by contributing to the degradation of connective tissue. We investigated the molecular mechanism by which DPPIV contributes to the destruction of connective tissue. DPPIV itself did not show gelatinase or collagenase activity toward human type I collagen, but it promoted the activity of the host-derived matrix metalloproteinase 2 (MMP-2) (gelatinase) and MMP-1 (collagenase). DPPIV bound to fibronectin and mediated the adhesion of P. gingivalis to fibronectin. Mutant DPPIV with catalytic Ser mutagenized to Ala (DPPSA) did not accelerate the degradation of collagen and gelatin by MMPs but retained fibronectin-binding activity. The adhesion of human gingival fibroblasts and NIH 3T3 cells to fibronectin was inhibited by DPPIV. Strain 4351ADPPSA exhibited an intermediate level of virulence in mice, between that of the strain expressing wild-type DPPIV (4351ADPP) and that of the strain harboring only the plasmid vector (4351AVEC). It is suggested that both activity promoting the degradation of collagen and gelatin and binding to fibronectin are required for full virulence. These results reveal novel biological functions of DPPIV and suggest a pathological role in the progression of periodontitis. 相似文献
30.
Prospective clinical evaluation of the serologic tuberculous glycolipid test in combination with the nucleic acid amplification test 总被引:4,自引:0,他引:4
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Maekura R Kohno H Hirotani A Okuda Y Ito M Ogura T Yano I 《Journal of clinical microbiology》2003,41(3):1322-1325
We have conducted a prospective controlled multicenter study to evaluate differences in the levels of clinical utility of the tuberculous glycolipid (TBGL) serodiagnostic test and the nucleic acid amplification test in patients with smear-negative active pulmonary tuberculosis (TB). The TBGL test and the PCR test were individually not so useful for the rapid diagnosis of smear-negative active pulmonary TB. However, clinical utility was considerably improved by using the TBGL test and the PCR test in combination, especially in patients with smear-negative and culture-negative active pulmonary TB and in patients with minimally advanced lesions. 相似文献