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排序方式: 共有4310条查询结果,搜索用时 31 毫秒
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Taichi Goto Gojiro Nakagami Takeo Minematsu Sanai Tomida Masamichi Shinoda Koichi Iwata Hiromi Sanada 《Experimental dermatology》2019,28(9):1010-1016
Cutaneous wound pain causes physical and psychological stress for patients with wounds. Previous studies reported that stress induces hyperalgesia and deteriorates wound healing. However, the effect of the stress response such as in hypothalamic‐pituitary‐adrenal (HPA) axis on local wound area is unclear. We aimed to investigate the effects of a stress response on the mechanical withdrawal threshold in the local wound area and describe the identification of a wound pain exacerbation. We topically injected adrenocorticotropic hormone (ACTH) into the granulation tissue of full‐thickness cutaneous wound model rats on the fifth day postwounding and measured the mechanical withdrawal thresholds, cytochrome P450 2Bs levels and concentration of 5,6‐epoxyeicosatrienoic acid in wound exudate. We found that ACTH induced mechanical hypersensitivity at 4 and 6 hours after injection (P = .004 and .021, respectively), and increased gene expression of cytochrome P450 2B12 expression (P = .046). Concentration of 5,6‐EET in the wound exudate was moderately correlated with the mechanical withdrawal threshold (r = ?.630). Finally, the mechanical withdrawal threshold in the 5,6‐EET group was significantly lower than that in the control group at 2 hours after the injection (P = .015). We propose that 5,6‐EET is one of the most promising contributors to the wound pain exacerbation. These findings could guide clinical wound and pain management. 相似文献
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Kanji Takeo Eric Virtudazo Misako Ohkusu Susumu Kawamoto Shoko Ito-Kuwa Sigeji Aoki 《Nippon Ishinkin Gakkai Zasshi》2006,47(4):257-262
In Cryptococcus neoformans the DNA content of cells having tiny buds varied rather widely, depending on growth phases and strains used. Typically, buds of C. neoformans emerged soon after initiation of DNA synthesis in the early exponential phase. However, bud emergence was delayed to G2 during transition to the stationary phase, and in the early stationary phase budding scarcely occurred, although roughly half of the cells completed DNA synthesis. The timing of budding in C. neoformans was shifted to later cell cycle points with progression of the growth phase of the culture. Similarly, a deficit in oxygen was demonstrated to delay the timing of budding, prolong the G2 phase and cause accumulation of cells after DNA synthesis, but before commitment to budding. The C. neoformans homologue of the main cell cycle control gene CDC28/Cdc2 was isolated using degenerate RT-PCR. The full-length coding region was then amplified using primers to target the regions around the start and stop codons. The gene was called CnCdk1 and was found to have high homologies to S. cerevisiae CDC28 and S. pombe cdc2. To determine its function, its ability to rescue S. cerevisiae cdc28-temperature sensitive mutants was tested. S. cerevisiae cdc28-4 and cdc28-1N strains transformed with the pYES2-CnCdk1 construct exhibited growth at the restrictive temperature. Results of the sequence analysis and the ability of CnCdk1 to complement the S. cerevisiae cdc28-ts mutations support its assumed role as the CDC28/cdc2 homologue in C. neoformans. 相似文献
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Tanaka Takeo Kobayashi Masao Saito Osamu Kamada Nanao Kuramoto Atsushi Usui Tomofusa 《Clinica chimica acta; international journal of clinical chemistry》1981,117(2):121-131
The biochemical activities of 8 lysosomal acid hydrolases in leukemic cells from 48 patients were examined. Characteristic alterations were found in α-mannosidase, β-galactosidase and N-acetyl-β-glucosaminidase activities of leukemic cells. The level of α-mannosidase activity was much higher in myelo(mono)genous leukemias (AML, AMoL, AMMoL, CML and CMMoL) than in lymphogenous ones (ALL, T-cell leukemia, hairy cell leukemia and CLL) without exception. The β-galactosidase activity also differed as a result of α-mannosidase, except in T-cell leukemia. In T-cell leukemia it was within the range of normal lymphocytes, but in the other lymphogenous leukemias it was significantly below normal. N-acetyl-β-glucosaminidase activity in myelo(mono)genous leukemic cells was above the range of normal granulocytes. The changes in these enzyme levels were consistent. The lymphocytic or myelocytic nature of three cases of acute undifferentiated leukemia could be determined by enzyme studies. In two cases it was lymphocytic and in one it was myelocytic. The enzymatic abnormalities were also found in morphologically mature neutrophils from patients with not only chronic types (CML, CMMoL) but also acute types (AMoL, AMMoL) of leukemias, and were similar to those of their respective leukemic cells. Analysis of lysosomal enzymes (at least three of those mentioned above), can elucidate one of the biochemical properties of leukemic cells and may be valuable in the differentiation of leukemias. 相似文献
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OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources. 相似文献
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Since 1903, Marchiafava‐Bignami disease has been recognized as a rare syndrome with focal demyelination and necrosis in the corpus callosum, which is usually found in chronic alcoholics. It extends into the neighboring white matter and occasionally as far as the subcortical regions. We report a Japanese patient with Marchiafava‐Bignami disease associated with alcohol abuse, who had traveled around Western Europe, North America and China for more than 30 years. As he suffered extreme delirium in the early stages we administered a low dose (10 mg) of mianserin hydrochloride. He was very irritable and uncooperative on admission, after 20 days his delirium had disappeared and his temper had become very calm and mild. After 40 days, his intelligence level increased substantially as measured by various neuropsychological tests. 相似文献
8.
Devin V Amin Takeo Kanade Anthony M DiGioia Branislav Jaramaz 《Computer aided surgery》2003,8(1):1-16
OBJECTIVE: To allow non-invasive registration of the bone surface for computer-assisted surgery (CAS), this investigation reports the development and evaluation of intraoperative registration using 2D ultrasound (US) images. This approach employs automatic segmentation of the bone surface reflection from US images tagged with the 3D position to enable the application of CAS to minimally invasive procedures. METHODS: The US-based registration method was evaluated in comparison to point-based registration, which is the predominant method in current clinical use. The absolute accuracy of the US-based registration was determined using a phantom pelvis, with fiducial registration providing the ground truth. The relative accuracy was determined by an intraoperative study comparing the US registration to the point-based registration obtained as part of the HipNav experimental protocol. RESULTS: The phantom pelvis study demonstrated equivalent accuracy between point- and US-based registration under in vitro conditions. In the intraoperative study, the US-based registration was sufficiently consistent with the point-based registration to warrant larger-scale clinical trials of this non-invasive registration method. CONCLUSION: Ultrasound-based registration eliminates the need for physical contact with the bone surface as in point-based registration. As a result, non-invasive registration could fully unlock the potential of computer-assisted surgery, enabling development of the next generation of minimally invasive surgical procedures. 相似文献
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