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991.
C. P. Li F. Y. Lee S. J. Hwang F. Y. Chang H. C. Lin R. H. Lu M. C. Hou C. J. Chu C. C. Chan J. C. Luo S. D. Lee 《Scandinavian journal of gastroenterology》2013,48(5):520-523
A study was undertaken to compare two new methods of capillary blood flow measurement, namely fluorescein flowmetry (FF) and laser Doppler flowmetry (LDF). The blood flow was measured in a pelvic pouch during its construction and in the completed ileoanal anastomosis in 12 patients. There was a high correlation between the two methods (correlation coefficient, 0.78) (p <0.01) when the blood flow was measured in the pelvic pouch. The correlation coefficient between the two methods for the difference between the blood flow in the pelvic pouch at the site of the planned anastomosis when the pouch resided in the abdomen and that in the completed ileoanal anastomosis was r = 0.99 (n = 12, p< 0.001); the reduction amounted to 25% as measured by FF and 27% as measured by LDF (n = 12, p < 0.01). All ileoanal anastomoses healed perfectly, the lowest FF and LDF values being 0.004 density units/sec and 0.3 V, respectively. The results indicate that either method can be considered for measuring capillary blood flow. 相似文献
992.
993.
H. W. Hou Q. S. Li G. Y. H. Lee A. P. Kumar C. N. Ong C. T. Lim 《Biomedical microdevices》2009,11(3):557-564
Cell deformability is an important biomarker which can be used to distinguish between healthy and diseased cells. In this
study, microfluidics is used to probe the biorheological behaviour of breast cancer cells in an attempt to develop a method
to distinguish between non-malignant and malignant cells. A microfabricated fluidic channel design consisting of a straight
channel and two reservoirs was used to study the biorheological behaviour of benign breast epithelial cells (MCF-10A) and
non-metastatic tumor breast cells (MCF-7). Quantitative parameters such as entry time (time taken for the cell to squeeze
into the microchannel) and transit velocity (speed of the cell flowing through the microchannel) were defined and measured
from these studies. Our results demonstrated that a simple microfluidic device can be used to distinguish the difference in
stiffness between benign and cancerous breast cells. This work lays the foundation for the development of potential microfluidic
devices which can subsequently be used in the detection of cancer cells.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
995.
Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is one of the highly pathogenic shrimp viruses. In this study,
IHHNV capsid protein (CP) was recombinantly expressed in Escherichia coli and found to self-assemble into virus-like particles (VLPs) with homogeneous size and shape similar to native IHHNV particles.
Furthermore, we found that IHHNV-VLPs encapsidate RNA and DNA with a predominant size of 0.5 kb. Stability experiments revealed
that the VLP could not be disassembled by EDTA, but its structure was completely disrupted by dithiothreitol (DTT). Non-reducing
SDS/PAGE showed that no intermolecular disulfide bonds were formed between the CP molecules, suggesting that intra-CP disulfide
bonds are essential for maintaining the structural integrity of the capsid. In addition, indirect immunofluorescence microscopy
analysis showed that the VLPs could efficiently enter primary hemocytes of the shrimp Litopenaeus vannamei, which implied that IHHNV-VLPs may be promising vehicles for the delivery of antiviral agents.
Luhong Hou and Hao Wu contributed equally to this paper. 相似文献
996.
Ning-ning Shan Xiao-juan Zhu Qian Wang Chun-yan Wang Ping Qin Jun Peng Ming Hou 《Haematologica》2009,94(11):1603-1607
To evaluate the effects of high-dose dexamethasone (HD-DXM) on the balance of interleukin-18 (IL-18) and its endogenous antagonist IL-18 binding protein (IL-18BP) in ITP patients, IL-18, IL-18BP as well as IFN-γ, IL-4 plasma levels and platelet counts were determined in 17 ITP patients receiving DXM 40 mg/day for four consecutive days and in 24 healthy subjects. Using RT-PCR, the mRNA expression of IL-18, IL-18BP, IFN-γ, IL-4, T-box (T-bet) and GATA-binding protein 3(GATA-3) were studied in all subjects. The in vitro effects of DXM on IL-18BP and IL-18 of peripheral blood mononuclear cells (PBMCs) were studied by ELISA. HD-DXM administration increased IL-18BP and reduced IL-18 expression significantly (p<0.05), which resulted in a downregulation of IL-18/IL-18BP ratio p<0.05). In vitro, DXM had a significant effect on secretion of IL-18BP while diminishing IL-18 release from cultures of PBMCs. These results suggest that downregulation of IL-18/IL-18BP might account for its clinical efficacy of HD-DXM in active ITP. 相似文献
997.
998.
999.
1000.
Bihua Bie Yan Wang You-Qing Cai Zhi Zhang Yuan-Yuan Hou Zhizhong Z Pan 《Neuropsychopharmacology》2012,37(13):2780-2788
The rewarding properties of opioids are essential driving force for compulsive drug-seeking and drug-taking behaviors in the development of opioid-mediated drug addiction. Prior drug use enhances sensitivity to the rewarding effects of subsequently used drugs, increasing vulnerability to relapse. The molecular mechanisms underlying this reward sensitization are still unclear. We report here that morphine that induced reward sensitization, as demonstrated by reinstatement of the behavior of conditioned place preference (CPP) with sub-threshold priming morphine, epigenetically upregulated the output activity of Ngf encoding the nerve growth factor (NGF) by increasing histone H4 acetylation in the rat central nucleus of the amygdala (CeA). NGF locally infused into the CeA mimicked the morphine effect in inducing new functional delta-opioid receptor (DOR) that was required for the reward sensitization, and morphine-induced reward sensitization was inhibited by blocking NGF receptor signaling in the CeA. Histone deacetylase inhibitors that increased the acetylation level at the Ngf promoter and NGF expression in the CeA also induced reward sensitization in a CeA NGF signaling- and DOR-dependent manner. Furthermore, CeA-applied NGF substituted prior morphine to induce reward sensitization in naive rats and also substituted priming morphine to reinstate the CPP induced by prior morphine. Thus, epigenetic upregulation of NGF activity in the CeA may promote the behavior of opioid reward and increase the sensitivity to the rewarding effect of subsequent opioids, a potentially important mechanism in drug addiction. 相似文献