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排序方式: 共有1471条查询结果,搜索用时 15 毫秒
31.
Coding for spatial goals in the prelimbic/infralimbic area of the rat frontal cortex 总被引:2,自引:0,他引:2 下载免费PDF全文
Hok V Save E Lenck-Santini PP Poucet B 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(12):4602-4607
Finding one's way in space requires a distributed neural network to support accurate spatial navigation. In the rat, this network likely includes the hippocampus and its place cells. Although such cells allow the organism to locate itself in the environment, an additional mechanism is required to specify the animal's goal. Here, we show that firing activity of neurons in medial prefrontal cortex (mPFC) reflects the motivational salience of places. We recorded mPFC neurons from rats performing a place navigation task, and found that a substantial proportion of cells in the prelimbic/infralimbic area had place fields. A much smaller proportion of cells with such properties was found in the dorsal anterior cingulate area. Furthermore, the distribution of place fields in prelimbic/infralimbic cells was not homogeneous: goal locations were overrepresented. Because such locations were spatially dissociated from rewards, we suggest that mPFC neurons might be responsible for encoding the rat's goals, a process necessary for path planning. 相似文献
32.
Jeroen N. Stoop Christopher A. Tibbitt Willem van Eden John H. Robinson Catharien M. U. Hilkens 《Immunology》2013,138(1):68-75
Rheumatoid arthritis (RA) is a debilitating autoimmune disease characterized by chronic inflammation of the synovial joints. Collagen‐induced arthritis (CIA) and proteoglycan‐induced arthritis (PGIA) are mouse models of inflammatory arthritis; CIA is a T helper type 17 (Th17) ‐dependent disease that is induced with antigen in complete Freund's adjuvant, whereas PGIA is Th1‐mediated and is induced using antigen in dimethyldioctadecyl‐ammonium bromide (DDA) as an adjuvant. To investigate whether the type of adjuvant determines the cytokine profile of the pathogenic T cells, we have compared the effect of CFA and DDA on T‐cell responses in a single arthritis model. No differences in incidence or disease severity between aggrecan‐T‐cell receptor transgenic mice immunized with aggrecan in either CFA or DDA were observed. Immunization with CFA resulted in a higher proportion of Th17 cells, whereas DDA induced more Th1 cells. However, the levels of interleukin‐17 (IL‐17) produced by T cells isolated from CFA‐immunized mice after antigen‐specific stimulation were not significantly different from those found in DDA‐immunized mice, indicating that the increased proportion of Th17 cells did not result in significantly higher ex vivo IL‐17 levels. Hence, the choice of adjuvant can affect the overall proportions of Th1 and Th17 cells, without necessarily affecting the level of cytokine production or disease incidence and severity. 相似文献
33.
Browne Julia Cather Corinne Zvonar Vanya Thayer Katherine Skiest Hannah Arntz Diana Kritikos Katherine Schnitzer Kristina Brown Hannah Evins A. Eden Donovan Abigail 《Community mental health journal》2021,57(5):864-871
Community Mental Health Journal - The mortality disparity for persons with schizophrenia spectrum disorders (SSDs) due to cardiovascular disease is a devastating problem. Many risk factors are... 相似文献
34.
Athena Hadjixenofontos Michael A. Schmidt Patrice L. Whitehead Ioanna Konidari Dale J. Hedges Harry H. Wright Ruth K. Abramson Ramkumar Menon Scott M. Williams Michael L. Cuccaro Jonathan L. Haines John R. Gilbert Margaret A. Pericak‐Vance Eden R. Martin Jacob L. McCauley 《Annals of human genetics》2013,77(1):9-21
Despite the increasing speculation that oxidative stress and abnormal energy metabolism may play a role in Autism Spectrum Disorders (ASD), and the observation that patients with mitochondrial defects have symptoms consistent with ASD, there are no comprehensive published studies examining the role of mitochondrial variation in autism. Therefore, we have sought to comprehensively examine the role of mitochondrial DNA (mtDNA) variation with regard to ASD risk, employing a multi‐phase approach. In phase 1 of our experiment, we examined 132 mtDNA single‐nucleotide polymorphisms (SNPs) genotyped as part of our genome‐wide association studies of ASD. In phase 2 we genotyped the major European mitochondrial haplogroup‐defining variants within an expanded set of autism probands and controls. Finally in phase 3, we resequenced the entire mtDNA in a subset of our Caucasian samples (~400 proband‐father pairs). In each phase we tested whether mitochondrial variation showed evidence of association to ASD. Despite a thorough interrogation of mtDNA variation, we found no evidence to suggest a major role for mtDNA variation in ASD susceptibility. Accordingly, while there may be attractive biological hints suggesting the role of mitochondria in ASD our data indicate that mtDNA variation is not a major contributing factor to the development of ASD. 相似文献
35.
On the question of the integration of exogenous bacterial DNA into plant DNA. 总被引:5,自引:0,他引:5 下载免费PDF全文
A Kleinhofs F C Eden M D Chilton A J Bendich 《Proceedings of the National Academy of Sciences of the United States of America》1975,72(7):2748-2752
Extensive studies with pea, tomato, and barley failed to confirm the evidence presented by previous investigators for integration or replication of exogenously applied bacterial DNA in these plants. Labeled DNA of buoyant density in CsCl intermediate between that of high density donor bacterial DNA and of plant DNA was never observed with axenic plants. Intermediate peaks, similar to those used as evidence for recombination by earlier investigators, were observed only when the plants were contaminated with bacteria. Plant DNA prepared by a published procedure [Ledoux, L. & Huart, R. (1969) J. Mol. Biol. 43, 243-262] was found to be contaminated with unidentified impurities. Such DNA was partially protected from the action of DNase and produced aberrant banding patterns in CsCl after shearing. Much of the published evidence for integration of foreign DNA in plants is based upon experiments with plant DNA prepared by this procedure. We conclude that contamination is the likely explanation for what has been interpreted as evidence for integration. 相似文献
36.
Hidetomo Nakamoto Xue‐Qing Yu Suhnggwon Kim Hideki Origasa Hongguang Zheng Jianghua Chen Kwon Wook Joo Suchai Sritippayawan Qinkai Chen Hung‐Chun Chen Yoshiharu Tsubakihara Hirofumi Tamai Sang Heon Song Indralingam Vaithilingam Kang Wook Lee Kuo‐Hsiung Shu Stanley Hok‐King Lo Masanao Isono Hajimu Kurumatani Kiyonobu Okada Hiroyuki Kanoh Takashi Kiriyama Shunsuke Yamada Toshiro Fujita 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2020,24(1):42-55
TRK‐100STP, a sustained‐release preparation of the orally active prostacyclin analogue beraprost sodium, targets renal hypoxia. This study aimed to show the superiority of TRK‐100STP over placebos in patients with chronic kidney disease (with either primary glomerular disease or nephrosclerosis) to determine the recommended dose. CASSIOPEIR (Chronic Renal Failure Asian Study with Oral PGI2 Derivative for Evaluating Improvement of Renal Function) was a randomized, double‐blind, placebo‐controlled study conducted at 160 sites in seven Asia‐Pacific countries and regions. Eligible patients (n = 892) were randomized to TRK‐100STP 120, 240 μg, or placebo for a treatment period of up to 4 years. The primary efficacy endpoint was time to first occurrence of a renal composite: doubling of serum creatinine or occurrence of end‐stage renal disease. No significant differences were observed in composite endpoints between TRK‐100STP and placebo (P = 0.5674). Hazard ratios (95% CI) in the TRK‐100STP 120 and 240 μg vs. placebo groups were 0.98 (0.78, 1.22) and 0.91 (0.72, 1.14), respectively. The overall incidence of adverse events and adverse drug reactions was comparable between treatment arms. 相似文献
37.
Lena Nordström Sandra Sernbo Patrik Eden Kirsten Grønbæk Arne Kolstad Riikka Räty Marja‐Liisa Karjalainen Christian Geisler Elisabeth Ralfkiær Christer Sundström Anna Laurell Jan Delabie Mats Ehinger Mats Jerkeman Sara Ek 《British journal of haematology》2014,166(1):98-108
Mantle cell lymphoma (MCL) is an aggressive B cell lymphoma, where survival has been remarkably improved by use of protocols including high dose cytarabine, rituximab and autologous stem cell transplantation, such as the Nordic MCL2/3 protocols. In 2008, a MCL international prognostic index (MIPI) was created to enable stratification of the clinical diverse MCL patients into three risk groups. So far, use of the MIPI in clinical routine has been limited, as it has been shown that it inadequately separates low and intermediate risk group patients. To improve outcome and minimize treatment‐related morbidity, additional parameters need to be evaluated to enable risk‐adapted treatment selection. We have investigated the individual prognostic role of the MIPI and molecular markers including SOX11, TP53 (p53), MKI67 (Ki‐67) and CCND1 (cyclin D1). Furthermore, we explored the possibility of creating an improved prognostic tool by combining the MIPI with information on molecular markers. SOX11 was shown to significantly add prognostic information to the MIPI, but in multivariate analysis TP53 was the only significant independent molecular marker. Based on these findings, we propose that TP53 and SOX11 should routinely be assessed and that a combined TP53/MIPI score may be used to guide treatment decisions. 相似文献
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