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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Hayashi T Tsujii S Iburi T Tamanaha T Yamagami K Ishibashi R Hori M Sakamoto S Ishii H Murakami K 《Biomedical research (Tokyo, Japan)》2007,28(6):281-285
To elucidate the sustainable effects of laughter on gene expression, we recruited type 2 diabetic patients who were in-patient for receiving self-management education and examined time-dependent regulation for gene expression by laughter. Two-day experiment was performed. On one day, the patients watched comic video and laughed together with hospital staffs. On the other day, they participated in an inpatient diabetes educational program. Blood samples were collected before and 1.5, 4 h after watching comic video or spending lecture time, and changes in gene expression were comprehensively analyzed by microarray technique. Of the 41,000 genes analyzed, the laughter relatively up-regulated 39 genes, among which, 27 genes were relatively increased in the expression for all the observation period after watching comic video. By functional classification of these genes, 14 genes were found to be related to natural killer cell activity. No genes were included that are directly involved in blood glucose regulation, though successive suppression of postprandial blood glucose levels was observed. These results suggest that the laughter influences the expression of many genes classified into immune responses, and may contribute to amelioration of postprandial blood glucose elevation through a modulation of NK cell activity caused by up-regulation of relating genes. 相似文献
992.
Kojima T Freitas PH Ubaidus S Suzuki A Li M Yoshizawa M Oda K Maeda T Kudo A Saito C Amizuka N 《Biomedical research (Tokyo, Japan)》2007,28(4):219-229
We aimed to histologically elucidate whether bioresorbable plates (DeltaSystem) can induce cortical bone formation, which is essential for long-lasting bone augmentation. Standardized bone defects in rat calvariae were covered with a convexly-shaped DeltaSystem plate, and then processed for histological observations. At 1 week, alkaline phosphatase-positive osteoblasts were seen in the newly-formed bone extending from the cavity's bottom, indicating accelerated osteogenesis. A thick layer of soft connective tissue positive for periostin, a hallmark of periosteum, covered this new bone. At 2 weeks, a spongy bone had filled the cavity up to half its height. The inner layer of the soft tissue facing the spongy bone revealed abundant periostin and osteopontin, and had many tartrate-resistant acid phosphatase-positive osteoclasts. At 4 weeks, this layer had given rise to thin new bony matrices without relation to the spongy bone arising from the cavity. These bone matrices had been thickened by 8 weeks, and turned into a thick cortical bone outlining the regenerated bone at 12 weeks. Thus, our study has provided histological evidences of cortical osteogenesis when DeltaSystem plates are used for bone augmentation procedures. 相似文献
993.
Sato T Miura T Nozaka H Katayama Y Moriuchi A Nakamura S Zheng Z Takamatsu T 《Rinsho byori. The Japanese journal of clinical pathology》2007,55(4):344-350
Many systems have already been designed and successfully used for clinical laboratory and pathological examination. The evolution of image analysis was enabled when analog images of the original glass slides could be transferred to digital images with the rapid development of virtual microscopy and virtual slides depended upon computer technologies. Today, whole slide can be acquired by virtual microscopes. The applications of virtual microscopy and virtual slides for teaching, diagnosis, telepathology, and research are more widely used than those of real microscope and real glass slides. In traditional cancer diagnosis, pathologists examine biopsies to make diagnostic assessments largely based on two-dimensional cell morphology and tissue distribution. These assessments are subjective and often show considerable variability. However, automated cancer diagnostic system based on three-dimensional image analysis based on nuclear bulging sign enables objective judgments using quantitative measurements. We expect that the shortage of pathologists will be improved when an automated cancer diagnosis system is developed. 相似文献
994.
Renal damage in obstructive nephropathy is decreased in Skp2-deficient mice 总被引:1,自引:0,他引:1 下载免费PDF全文
Suzuki S Fukasawa H Kitagawa K Uchida C Hattori T Isobe T Oda T Misaki T Ohashi N Nakayama K Nakayama KI Hishida A Yamamoto T Kitagawa M 《The American journal of pathology》2007,171(2):473-483
Ubiquitin-dependent degradation of the cyclin-dependent kinase inhibitor p27 mediated by SCF-Skp2 ubiquitin ligase is involved in cell cycle regulation. Proliferation of tubular cells is a characteristic feature in obstructed kidneys of unilateral ureteral obstruction. Comparing Skp2(+/+) mice with Skp2(-/-) mice, we investigated the involvement of Skp2, a component of SCF-Skp2 ubiquitin ligase for p27, in the progression of renal lesions in unilateral ureteral obstructed kidneys. mRNA expression of Skp2 was markedly increased in the obstructed kidneys from Skp2(+/+) mice and peaked 3 days after unilateral ureteral obstruction. Renal atrophy, tubular dilatation, tubulointerstitial fibrosis, and increases in alpha-smooth muscle actin expression, the number of tubular cells, and proliferating tubular cells positive for Ki67 were observed in the obstructed kidneys from Skp2(+/+) mice; however, these findings were significantly attenuated in Skp2(-/-) mice. The p27 protein level was increased in the obstructed kidneys but was significantly greater in Skp2(-/-) mice. The number of Ki67-positive p27-negative cells was lower in obstructed kidneys from Skp2(-/-) mice than Skp2(+/+) mice, whereas that of Ki67-negative p27-positive cells was greater in Skp2(-/-) mice. These findings suggest that p27 accumulation, which results from SCF-Skp2 ubiquitin ligase deficiency in Skp2(-/-) mice, is involved in the amelioration of renal damage induced by obstructive nephropathy. 相似文献
995.
Nakamura Y Yasukochi M Kobayashi S Uehara K Honda A Inoue R Imanaga I Uehara A 《Pflügers Archiv : European journal of physiology》2007,453(4):455-462
Lysophosphatidylcholine (LPC) is metabolized from a membrane phospholipid and modulates a variety of channels in the plasma
membrane (PM). We examined LPC modulation of cardiac ryanodine receptor (RyR) channels in the sarcoplasmic reticulum (SR)
using the planar lipid bilayer method to measure the single-channel currents. Micromolar concentrations of LPC increased the
open probability of the reconstituted RyR channels irrespective of whether LPC was added to the cis or trans chamber. LPC
also increased the membrane capacitance of the bilayer. The effects of LPC contrasted well with those of sphingosylphosphorylcholine
(SPC). Taken together, these results suggest that amphipathic lipid LPC does not bind directly to the RyR channel protein,
but rather, is incorporated into the bilayer membrane and activates the channel. Thus, we consider cell membrane-derived LPC
to be a putative endogenous mediator that activates not only plasma membrane channels but also RyR channels and induces arrhythmogenic
Ca2+ mobilization in cardiomyocytes. 相似文献
996.
997.
Shimamura M Huang YY Okamoto N Suzuki N Yasuoka J Morita K Nishiyama A Amano Y Mishina T 《European journal of immunology》2007,37(7):1836-1844
We have demonstrated that analogues of alpha-mannosyl ceramide (alpha-ManCer) consisting of a series of immunosuppressive 2-aminoalcohol derivatives in place of sphingosine promote a greater immune response from mouse invariant Valpha19-Jalpha26 (AV19-AJ33) TCR-bearing NKT (Valpha19 NKT) cells than alpha-ManCer itself. To further characterize the immune responses of Valpha19 NKT cells to the alpha-ManCer analogues, cytokine production by the cells was examined in detail. We found that certain alpha-ManCer derivatives individually induced either Th1- or Th2-dominant cytokine production in culture. The Th1- or Th2-biased immune responses of Valpha19 NKT cells were dependent on MHC class I-like MR1, since they were induced by coculture with the MR1 transfectants previously loaded with the glycolipids and were inhibited in the presence of anti-MR1 antiserum. Presumably, the recognition of the alpha-mannosyl residue of the alpha-ManCer analogues by the invariant TCR is individually modulated, depending on the altered interaction with the groove of the antigen-presenting MR1. Priming of the Valpha19 invariant TCR-transgenic mice in vivo with these glycolipid derivatives resulted in the induction of the Th1- or Th2-biased immune responses. Thus, these alpha-ManCer derivatives are likely to be useful in immunotherapy for either Th1 or Th2 excess autoimmune diseases, modulating the function of Valpha19 NKT cells. 相似文献
998.
Tian JR Ishiyama A Demer JL 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(4):529-541
Dynamic changes of deficits in canal and otolith vestibulo-ocular reflexes (VORs) to high acceleration, eccentric yaw rotations
were investigated in five subjects aged 25–65 years before and at frequent intervals 3–451 days following unilateral vestibular
deafferentation (UVD) due to labyrinthectomy or vestibular neurectomy. Eye and head movements were recorded using magnetic
search coils during transients of directionally random, whole-body rotation in darkness at peak acceleration 2,800°/s2. Canal VORs were characterized during rotation about a mid-otolith axis, viewing a target 500 cm distant until rotation onset
in darkness. Otolith VOR responses were characterized by the increase in VOR gain during identical rotation about an axis
13 cm posterior to the otoliths, initially viewing a target 15 cm distant. Pre-UVD canal gain was directionally symmetrical,
averaging 0.87 ± 0.02 (±SEM). Contralesional canal gain declined from pre-UVD by an average of 22% in the first 3–5 days post-UVD,
before recovering to an asymptote of close 90% of pre-UVD level at 1–3 months. This recovery corresponded to resolution of
spontaneous nystagmus. Ipsilesional gain declined to 59%, and showed no consistent recovery afterwards. Pre-UVD otolith gain
was directionally symmetrical, averaging 0.56 ± 0.02. Immediately after UVD, the contralesional otolith gain declined to 0.30 ± 0.02,
and did not recover. Ipsilesional otolith gain declined profoundly to 0.08 ± 0.03 (P < 0.01), and never recovered. In contrast to the modest and directionally symmetrical effect of UVD on the human otolith
VOR during pure translational acceleration, otolith gain during eccentric yaw rotation exhibited a profound and lasting deficit
that might be diagnostically useful in lateralizing otolith pathology. Most recovery of the human canal gain to high acceleration
transients following UVD is for contralesional head rotation, occurring within 3 months as spontaneous nystagmus resolves.
Grant support: United States Public Health Service grants DC-02952 and AG-09693. JLD is Leonard Apt Professor of Ophthalmology. 相似文献
999.
Kasirawat Sawangrat Masaki Morishita Kosuke Kusamori Hidemasa Katsumi Toshiyasu Sakane Akira Yamamoto 《Journal of pharmaceutical sciences》2018,107(11):2946-2956
Breast cancer resistance protein (BCRP) transporter is an efflux transporter that utilizes energy from adenosine triphosphate hydrolysis to push its substrates, regardless of the concentration gradient. Its presence on the apical membrane of the intestinal mucosa is a major obstacle for the intestinal absorption of its substrates. In this study, we examined the effects of various pharmaceutical excipients on the intestinal transport and absorption of sulfasalazine, a BCRP substrate. Four excipients, including 0.05% and 0.075% BL-9EX, 0.01% and 0.05% Brij 97, 0.075% Labrasol, and 0.05% and 0.1% Tween 20 decreased the secretory transport of sulfasalazine in an in vitro diffusion chamber. Further investigation in an in situ closed loop experiment in rats showed that 0.05% and 0.1% BL-9EX and 0.1% Brij 97 effectively enhanced the intestinal absorption of sulfasalazine while maintaining minimal toxicity to the intestinal mucosa. However, 0.1% Brij 97 also increased the intestinal absorption of 5(6)-carboxyfluorescein, a paracellular marker compound. These findings suggest that BL-9EX might effectively inhibit the BCRP-mediated efflux of sulfasalazine in vivo, indicating that BL-9EX could improve the intestinal absorption of sulfasalazine and other BCRP substrates. 相似文献
1000.