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排序方式: 共有5347条查询结果,搜索用时 31 毫秒
51.
Takamatsu S Teramoto K Kawamura T Kudo A Noguchi N Irie T Ochiai T Kumagai J Koike M Arii S 《Pathology international》2004,54(6):440-445
Intrabiliary growth of liver metastases from colorectal cancer has rarely been studied. A surgically resected case of a metastatic liver tumor with prominent intrabiliary growth derived from rectal cancer is reported. The patient was a 62-year-old man who had received a low anterior resection for rectal cancer in March 2000. He was re-admitted due to obstructive jaundice in January 2003, and was diagnosed with hepatic malignancy in segment II of the liver with an intrabiliary tumor extending from the intrahepatic bile duct of segment II to the common hepatic duct. He underwent a left hepatectomy, a partial resection of segment VI, and an extrahepatic bile duct resection with reconstruction of the biliary tract. In the resected specimen, there were whitish tumors of 3 cm and 1.5 cm in diameter in segments II and VI, respectively, and an intrabiliary tumor originating from the main tumor in segment II extended to the common hepatic duct. Both the liver tumors and the intrabiliary tumor consisted of a well- to moderately differentiated adenocarcinoma, which showed the same histological features as the rectal cancer. The immunohistochemical findings strongly supported that these tumors, including the intrabiliary growth, were liver metastasis from the rectal cancer. The intrabiliary invasion and growth of metastatic liver tumors has generally been overlooked, notwithstanding their frequently observed biological behavior. The present case is informative, and further investigation into this type of metastatic liver tumor may be warranted. 相似文献
52.
Shigeharu Kudo 《Anatomical record (Hoboken, N.J. : 2007)》1994,238(1):49-56
Localization of non-specific esterases, Cu-Zn superoxide dismutase and dehydropeptidase-I, in rat lung was investigated enzymecytochemically or immunohistochemically. Esterase was demonstrated in Clara cells, type II pneumocytes, and septal cells (or vitamin A-storing lung cells), to a somewhat lesser extent in type I pneumocytes and ciliated epithelial cells of the bronchioles, and to a minor extent in interstitial fibroblasts of the alveolar septum. Large amounts of esterase reaction product were deposited in the rough endoplasmic reticulum and the nuclear envelope in Clara cells, type II pneumocytes, and septal cells, in addition to smaller amounts in other organelles. No reaction product was found in macrophages (histiocytes) in alveolar septi and alveolar macrophages, except for the primary lysosomes or phagolysosomes and trace amounts in the Golgi vesicles, and none in endothelial cells of alveolar blood capillaries, except for primary lysosomes. Immunolocalization of Cu-Zn superoxide dismutase was generally limited to a particular area of Clara cells. A constriction occurred in the apical cytoplasm of Clara cells between an immunoreactive dome-like protrusion and the non-immunoreactive cytoplasm of the supranuclear area, and the dome-like protrusion appereared to be pinched off in a ball-like or oval from. Immunolocalization of dehydropeptidase-I was demonstrated in a dome-like protrusion or supranuclear area of Clara cells or throughout the cytoplasm and in the surface plasma membrane of mesothelial cells. The presence of these enzymes in Clara cells suggests a contribution to the detoxification system of the lung, together with cytochrome p-450-dependent monooxygenase systems. © 1994 Wiley-Liss, Inc. 相似文献
53.
Kazutoshi Kudo T. Ohtsuki 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,122(1):23-30
Subjects made a fast elbow extension movement to designated target in response to a go signal. In 45% of trials a stop signal
was presented after the go signal, to which subjects were asked to stop the movement as rapidly as possible. The interstimulus
interval (ISI), or time interval between the go and stop signals, was randomly varied between 0 and 200 ms. Electromyographic
(EMG) activity was recorded from biceps brachii and triceps brachii. Subjects could sometimes completely inhibit initiation
of the movements when the ISI was 0 ms, but could rarely do so when the ISI exceeded 100 ms. For responses that were initiated
but stopped on the way, the amplitude of the movement decreased linearly as the time interval (=modification time) from the
stop signal to EMG onset increased. The peak velocity increased linearly as the movement amplitude increased. This tendency
was similar to those previously reported in step-tracking movements with various amplitudes. In spite of the similarity in
the kinematics of the movement, the EMG pattern was different from that of step-tracking movement. While the initial agonist
burst (AG1) decreased linearly after the modification time exceeded 100 ms, the antagonist burst (ANT) increased compared
with the go trial for the modification time from 0 to 200 ms and decreased after the modification time exceeded 300 ms. This
change of activation is analogous to functional modification of middle-latency reflex EMG response to load, or cutaneous perturbation.
In conclusion, it is suggested that adaptive mechanisms, which would functionally modify the reflex responses, are also continuously
working during voluntary movements in response to sudden changes in environmental information.
Received: 3 November 1997 / Accepted: 3 February 1998 相似文献
54.
Aoki Y Saida T Nakano I Saito T Ikeguchi K Urabe T Nishiguchi E Suzuki H Takahashi K Mizuno Y 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(3):308-312
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis. 相似文献
55.
Moore DJ Zhang L Troncoso J Lee MK Hattori N Mizuno Y Dawson TM Dawson VL 《Human molecular genetics》2005,14(1):71-84
The identification of rare monogenic forms of Parkinson's disease (PD) has provided tremendous insight into the molecular pathogenesis of this disorder. Heritable mutations in alpha-synuclein, parkin, DJ-1 and PINK1 cause familial forms of PD. In the more common sporadic form of PD, oxidative stress and derangements in mitochondrial complex-I function are considered to play a prominent role in disease pathogenesis. However, the relationship of DJ-1 with other PD-linked genes and oxidative stress has not been explored. Here, we show that pathogenic mutant forms of DJ-1 specifically but differentially associate with parkin, an E3 ubiquitin ligase. Chemical cross-linking shows that pathogenic DJ-1 mutants exhibit impairments in homo-dimer formation, suggesting that parkin may bind to monomeric DJ-1. Parkin fails to specifically ubiquitinate and enhance the degradation of L166P and M26I mutant DJ-1, but instead promotes their stability in cultured cells. The interaction of parkin with L166P DJ-1 may involve a larger protein complex that contains CHIP and Hsp70, perhaps accounting for the lack of parkin-mediated ubiquitination. Oxidative stress also promotes an interaction between DJ-1 and parkin, but this does not result in the ubiquitination or degradation of DJ-1. Parkin-mediated alterations in DJ-1 protein stability may be pathogenically relevant as DJ-1 levels are dramatically increased in the detergent-insoluble fraction from sporadic PD/DLB brains, but are reduced in the insoluble fraction from parkin-linked autosomal recessive juvenile-onset PD brains. These data potentially link DJ-1 and parkin in a common molecular pathway at multiple levels that may have important implications for understanding the pathogenesis of inherited and sporadic PD. 相似文献
56.
57.
In vivo labeling of amyloid with BF-108 总被引:3,自引:0,他引:3
Suemoto T Okamura N Shiomitsu T Suzuki M Shimadzu H Akatsu H Yamamoto T Kudo Y Sawada T 《Neuroscience research》2004,48(1):65-74
Detection of aggregated amyloid-beta (Abeta) with a non-invasive imaging modality such as positron emission tomography (PET) was suggested to be ideal for the diagnosis of Alzheimer's disease (AD) prior to the onset of clinical symptoms. We have been searching for imaging probe candidates with a high affinity for aggregated Abeta in vitro and in vivo and high lipophilicity, a characteristic that allows for the permeation of the blood-brain barrier (BBB). As analyzed by Thioflavin T (ThT) assay and octanol/water partition coefficient test (PC), 3-diethylamino-6-(2-fluoroethyl)ethylaminoacridine (BF-108) were found to have high affinity for Abeta aggregates in vitro and high lipophilicity. Intravenously administrated BF-108 labeled Abeta aggregates injected into the amygdala as observed under a fluorescence microscope, showing this compound's permeability of BBB and an ability to label Abeta in vivo. BF-108 also labeled neuritic senile plaques (SPs), neurofibrillary tangles, and amyloid-laden vessels in temporal and hippocampal sections from AD patients. Following intravenous administration of BF-108 to an APP23 transgenic (TG) mouse, in vivo labeling of endogenous plaques was seen in brain sections by fluorescence microscopy. These properties suggest the potential utility of BF-108 for in vivo imaging of AD pathology. 相似文献
58.
We examined the action of high (2×10–8M) and low (6×10–9M) concentrations of atrial natriuretic factor (ANF) on water and urea transport in the rat inner medullary collecting duct (IMCD) using the in vitro microperfusion technique. We measured the hydraulic conductivity (Lp ×10–6 cm/atm per second) and both lumen-to-bath (P
u(lb)) and bath-to-lumen (P
u(bl)) 14C-urea permeabilities (P
u× 10–5 cm/s) in the absence and in the presence of vasopressin (VP). High concentrations of ANF were able to inhibit the maximum activity of (50 U/ml) VP-stimulated L
p but physiological concentration of ANF inhibit only submaximum activity (10 U/ml) of VP-stimulated L
p. The hydrosmotic effect of dibutyryl-cyclic 3,5 adenosine monophosphate (cAMP) (10–4M) was unchanged by high concentrations of ANF (2×10–8M). Also we found that high (10–4M) and low (10–6M) concentrations of exogenous cyclic 3,5-guanosine monophosphate (GMP) while unable to change the Lp in the absence of VP, decreased the maximum activity of VP-stimulated Lp significantly. We also found that ANF inhibits partially and in a reversible manner the VP-stimulated P
u(lb) but not the VP-stimulated P
u(bl). These results demonstrated that plasma concentrations of ANF observed during volume expansion (10–10M) are able to inhibit submaximum activity of VP-stimulated (10 U/ml) L
p in the rat IMCD, this effect seems to occur before cAMP formation and it appears to be mediated by cGMP. ANF (6× 10–9M) also reduced the VP-stimulated urea outflux. Therefore, the increase in water excretion produced by ANF could be explained, at least in part, by the inhibition by ANF of vasopressin effects on water and urea transport in the IMCD.This study was presented in part at the VI Latin American Congress of Nephrology, Brazil, October 1985 and at the Xth International Congress of Nephrology, London, July 1987. 相似文献
59.
Suzuki N Kudo K Sano Y Ito K 《International archives of allergy and immunology》2001,124(1-3):113-116
It is generally considered that tuberculosis (TB) is a disease which upregulates Th1 cell function. There is a hypothesis that infection of Mycobacterium tuberculosis may prevent allergic disorders such as bronchial asthma. However, our clinical experience of patients with TB somewhat conflicts this hypothesis. Hence, we investigated Th1/Th2 balance in the peripheral blood of patients with active TB by measuring serum levels of IgE antibody and by intracellular cytokine assay. We found that serum levels of IgE in the patients with active TB were significantly higher than in those with lung cancer or with COPD. In the TB patients, titers of IgE tended to correlate with disease severity. Intracellular cytokine assay demonstrated that IFN-gamma-positive cells were significantly decreased in the patients with active TB compared to normal controls. The ratio of IFN-gamma-positive (Th1-like)/IL-4-positive (Th2-like) cells was remarkably reduced in the TB patients (p < 0.0001). This ratio showed a significant negative correlation with erythrocyte sedimentation rate and with C-reactive protein. Therapy against TB for 2-3 months did not result in significant changes of the Th1/Th2 ratio. These findings suggest that infection of M. tuberculosis does not systematically upregulate Th1 cells in some patients, and is unlikely to prevent allergic disorders like asthma. 相似文献
60.
Motoshige Kudo Masakuni Shimizu Yasuhiko Akutsu Hisatoshi Lrnaya Mau Nan Chen Myota Miura 《Pathology international》1990,40(1):50-56
A case of cerebellar medulloblastoma with clusters of mature ganglion cells and glial cells is described. The patient, a 15 -year -old girl, underwent three operations followed each time by radiation and chemotherapy during the four-year clinical course. Histologically, the ganglion cells were clearly identifiable by their abundant eosino-philic cytoplasm, round nuclei with prominent nucleoli, tigroid granules, and argyrophilic fibrils and axons. Im-munohistochemically, the cells were NSE- and NF positive, and ultrastructurally they contained abundant tubules and filaments, neurosecretory granules and well developed rough endoplasmic reticulum. There were many cells transitional in appearance between primitive cells and mature ganglion cells. The tumor also had many mature yet atypical astrocytes and oligodendrocytes. The exact mechanism of the extensive neuronal and glial maturation of medulloblastoma cells is unclear, but the repetitive surgical interventions, radiation and chemotherapy might have had certain cytostatic effects on rapidly dividing medulloblastoma cells, giving them a chance to mature into postmitotic cells with potential for neuronal and glial differentiation. Acta Pathol Jpn 40: 50–56, 1990. 相似文献