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41.
Novelty and Familiarity Activations in PET Studies of Memory Encoding and Retrieval 总被引:16,自引:3,他引:13
Tulving Endel; Markowitsch Hans J.; Craik Fergus I. M.; Habib Reza; Houle Sylvain 《Cerebral cortex (New York, N.Y. : 1991)》1996,6(1):71-79
Nine young right-handed men viewed colored pictures of people,scenes, and landscapes. Then, 24 hr later while undergoing PETscanning, they viewed previously studied (OLD) pictures in onetype of scan, and previously not seen (NEW) pictures in another.The OLD-NEW subtraction of PET images indicates familiarity,and the NEW-OLD indicates novelty. Familiarity activations,signalling aspects of retrieval, were observed in the left andright frontal areas, and posterior regions bilaterally. Noveltyactivations were in the right limbic regions, and bilaterallyin temporal and parietal regions, including area 37. These latteractivations were located similarly to novelty activations inprevious PET studies using visual words and auditory sentences,suggesting the existence of brain regions specializing in transmodalnovelty assessment The effects of novelty are seen both be haviorallyand in replicable patterns of cortical and subcortical activation.We propose a "novelty/encoding hypothesis": (1) novelty assessmentrepresents an early stage of long-term memory encoding; (2)elaborate, meaning-based encoding processes operate on the incoming information to the extent of its novelty, and therefore(3) the probability of long-term storage of information vanesdirectly with the novelty of the information. 相似文献
42.
Anne L Clark Ann M Gillenwater Thomas G Collier Reza Alizadeh-Naderi Adel K El-Naggar Rebecca R Richards-Kortum 《Clinical cancer research》2003,9(13):4714-4721
PURPOSE: The goal of this study was to characterize features of normal and neoplastic oral mucosa using reflectance confocal microscopy. EXPERIMENTAL DESIGN: Oral cavity biopsies were acquired from 17 patients at the Head and Neck Clinic of The University of Texas M. D. Anderson Cancer Center who were undergoing surgery for squamous cell carcinoma within the oral cavity. Reflectance confocal images were obtained at multiple image plane depths from biopsies within 6 h of excision. After imaging, biopsies were fixed in 10% formalin and submitted for routine histological examination. Reflectance confocal images were compared with histological images from the same sample to determine which tissue features contribute to image contrast and can be potentially imaged using in vivo confocal microscopy. RESULTS: Confocal images were successfully acquired from 15 biopsy pairs from 17 patients. Depth-related changes in cell diameter and nuclear density were observed at multiple anatomical sites within the oral cavity. In squamous cell carcinomas, densely packed, pleomorphic tumor nuclei could be visualized with distinct differences in nuclear density and morphology distinguishable between confocal images of neoplastic and nonneoplastic oral cavity. Other features of noncancerous and cancerous oral tissue that could be identified in the confocal images included areas of inflammation, fibrosis, muscle fibers, and salivary glands. CONCLUSIONS: Our results support the potential for this tool to play a significant role in the clinical evaluation of oral lesions, real-time identification of tumor margins, and monitoring of response to therapeutic treatment. 相似文献
43.
Avi Shupak Reza Tabari Douglas J. Swarts Charles D. Bluestone William J. Doyle 《The Laryngoscope》1997,107(10):1409-1413
Middle ear negative pressure and effusions, decreased middle ear compliance, and abnormal tympanometry results have been described after diving on oxygen. Middle ear gas hyperoxia has been shown to down-regulate the eustachian tube ventilatory function (ETVF). The purpose of the present study was to investigate to what extent systemic hyperoxia in the face of air-equivalent middle ear gas composition might interfere with the ETVF. ETVF was investigated in four young adult female cynomolgus monkeys by the forced-response and inflation-deflation tests using air while the animals breathed either room air or 100% normobaric oxygen. Higher opening, closing, and steady-state pressures were observed under systemic hyperoxia. The percentage of the applied pressure equalized, and the maximal pressure change on a single swallow in the deflation test were both lower under hyperoxic conditions. The results show that systemic hyperoxia might impair ETVF. This observation adds to our understanding of the pathophysiology of middle ear dysfunction observed after diving on oxygen. 相似文献
44.
M. Ashraf P. Kumar M. Ashraf Reza Ragesh K. P. 《Indian journal of otolaryngology and head and neck surgery》2006,58(4):343-346
Pediatric neoplasm is next only to trauma as the most common cause of death. The cervicofacial malignancies presents a unique
challenge owing to potential adverse effects of both the disease process and the treatment employed on critical developing
head and neck structures.
This study comprised of 106 children below 12 years age group conducted during 1999–2003 at JNMC, Aligarh. Of 106 cases 70
were benign neoplasms and 36 malignant neoplasms. Nasopharynx was the commonest site of involvement. Nasopharyngeal angiofibroma
was the commonest benign tumour and lymphoma was the commonest malignant neoplasm. Team approach is required for mitigation
of the disease process. 相似文献
45.
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47.
Roham Sarmadian Reza Ghasemikhah Hossein Sarmadian Mahmood Khosravi Saeed Hassani 《Clinical Case Reports》2022,10(7)
We describe splenic infarction (SI), an infrequent condition, in an 82‐year‐old COVID‐19 patient with chronic atrial fibrillation (AF). COVID‐19 may cause thrombosis, and AF is a predisposing factor for splenic infarction. Suspicion of SI may be warranted in COVID‐19 patients with abdominal pain, especially if a predisposing factor exists. 相似文献
48.
The growing demand for wood-based panels for buildings and furniture and the increasing worldwide concern for reducing the pressure on forest resources require alternatives to wood raw materials. The agricultural industry not only can provide raw materials from non-wood plants but also numerous residues and side streams. This review supplies an overview of the availability, chemical composition, and fiber characteristics of non-wood lignocellulosic materials and agricultural residues, i.e., grow care residues, harvest residues, and process residues, and their relevance for use in wood panel manufacturing. During the crop harvest, there are millions of tons of residues in the form of stalks, among other things. Usually, these are only available seasonally without using storage capacity. Process residues, on the other hand, can be taken from ongoing production and processed further. Fiber characteristics and chemical composition affect the panel properties. Alternatives to wood with long fibers and high cellulose content offer sufficient mechanical strength in different panel types. In general, the addition of wood substitutes up to approximately 30% provides panels with the required strength properties. However, other parameters must be considered, such as pressing temperature, adhesive type, press levels, and pretreatments of the raw material. The search for new raw materials for wood panels should focus on availability throughout the year, the corresponding chemical requirements and market competition. Panel type and production process can be adapted to different raw materials to fit niche products. 相似文献
49.
Immune checkpoints in targeted-immunotherapy of pancreatic cancer: New hope for clinical development
Seyed Hossein Kiaie Mohammad Javad Sanaei Masoud Heshmati Zahra Asadzadeh Iman Azimi Saleh Hadidi Reza Jafari Behzad Baradaran 《药学学报(英文版)》2021,11(5):1083-1097
Immunotherapy has been recently considered as a promising alternative for cancer treatment. Indeed, targeting of immune checkpoint (ICP) strategies have shown significant success in human malignancies. However, despite remarkable success of cancer immunotherapy in pancreatic cancer (PCa), many of the developed immunotherapy methods show poor therapeutic outcomes in PCa with no or few effective treatment options thus far. In this process, immunosuppression in the tumor microenvironment (TME) is found to be the main obstacle to the effectiveness of antitumor immune response induced by an immunotherapy method. In this paper, the latest findings on the ICPs, which mediate immunosuppression in the TME have been reviewed. In addition, different approaches for targeting ICPs in the TME of PCa have been discussed. This review has also synopsized the cutting-edge advances in the latest studies to clinical applications of ICP-targeted therapy in PCa.KEY WORDS: Immune checkpoint, Pancreatic cancer, Tumor microenvironment, Immunotherapy, Clinical development 相似文献
50.
Jing Ma Adrien Guillot Zhihong Yang Bryan Mackowiak Seonghwan Hwang Ogyi Park Brandon J. Peiffer Ali Reza Ahmadi Luma Melo Praveen Kusumanchi Nazmul Huda Romil Saxena Yong He Yukun Guan Dechun Feng Pau Sancho-Bru Mengwei Zang Andrew MacGregor Cameron Ramon Bataller Frank Tacke Zhaoli Sun Suthat Liangpunsakul Bin Gao 《The Journal of clinical investigation》2022,132(14)
Intrahepatic neutrophil infiltration has been implicated in severe alcoholic hepatitis (SAH) pathogenesis; however, the mechanism underlying neutrophil-induced injury in SAH remains obscure. This translational study aims to describe the patterns of intrahepatic neutrophil infiltration and its involvement in SAH pathogenesis. Immunohistochemistry analyses of explanted livers identified two SAH phenotypes despite a similar clinical presentation, one with high intrahepatic neutrophils (Neuhi), but low levels of CD8+ T cells, and vice versa. RNA-Seq analyses demonstrated that neutrophil cytosolic factor 1 (NCF1), a key factor in controlling neutrophilic ROS production, was upregulated and correlated with hepatic inflammation and disease progression. To study specifically the mechanisms related to Neuhi in AH patients and liver injury, we used the mouse model of chronic-plus-binge ethanol feeding and found that myeloid-specific deletion of the Ncf1 gene abolished ethanol-induced hepatic inflammation and steatosis. RNA-Seq analysis and the data from experimental models revealed that neutrophilic NCF1-dependent ROS promoted alcoholic hepatitis (AH) by inhibiting AMP-activated protein kinase (a key regulator of lipid metabolism) and microRNA-223 (a key antiinflammatory and antifibrotic microRNA). In conclusion, two distinct histopathological phenotypes based on liver immune phenotyping are observed in SAH patients, suggesting a separate mechanism driving liver injury and/or failure in these patients. 相似文献