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Parker E.Ludwig Finosh G.Thankam Arun A.Patil Andrea J.Chamczuk Devendra K.Agrawal 《中国神经再生研究》2018,(1)
Many therapies with potential for treatment of brain injury have been investigated. Few types of cells have spurred as much interest and excitement as stem cells over the past few decades. The multipotentiality and self-renewing characteristics of stem cells confer upon them the capability to regenerate lost tissue in ischemic or degenerative conditions as well as trauma. While stem cells have not yet proven to be clinically effective in many such conditions as was once hoped, they have demonstrated some effects that could be manipulated for clinical benefit. The various types of stem cells have similar characteristics, and largely differ in terms of origin; those that have differentiated to some extent may exhibit limited capability in differentiation potential. Stem cells can aid in decreasing lesion size and improving function following brain injury. 相似文献
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Onkar Singh Shilpi Gupta Sonia Moses Devendra K. Jain 《Indian journal of gastroenterology》2009,28(3):88-92
Objective
To compare the effectiveness of percutaneous catheter drainage (PCD) and percutaneous needle aspiration (PNA) in the management of large (>10 cm diameter) liver abscesses. 相似文献26.
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D'Souza S Levy E Mack D Israel D Lambrette P Ghadirian P Deslandres C Morgan K Seidman EG Amre DK 《Inflammatory bowel diseases》2008,14(3):367-373
BACKGROUND: Some dietary foods are considered protective (vegetables and fruits), whereas others (fatty foods) are thought to enhance the risk for Crohn's disease (CD). The evidence, however, is inconsistent. METHODS: We postulated that specific dietary patterns may influence the risk for CD. A case-control study was carried out. Newly diagnosed CD cases with population and/or hospital-based controls < or =20 years were selected from 3 tertiary hospitals across Canada. Pre-disease diet was assessed using a validated food frequency questionnaire (FFQ) administered within 1 month of diagnosis. Factor analyses and unconditional logistic regression (adjusted) was used to determine gender-specific dietary patterns and assess associated risks for CD. Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were estimated. RESULTS: A total of 149 cases and 251 controls were included. The mean age (range) of the cases was 13.3 (2.6-20 years). There were more boys (61.1%). Four dietary patterns each were observed among both boys and girls. Pattern 1 in girls, characterized by meats, fatty foods, and desserts, was positively associated with CD (OR 4.7, 95% CI 1.6-14.2). Pattern 2, common to both boys and girls, was characterized by vegetables, fruits, olive oil, fish, grains, and nuts and was inversely associated with CD in both genders (girls: OR 0.3, 95% CI 0.1-0.9; boys: OR 0.2, 95% CI 0.1-0.5). CONCLUSIONS: Our results suggest that specific dietary patterns could be associated with higher or lower risks for CD in children. Larger prospective studies are required to confirm these findings. 相似文献
28.
Vijay Kumar Rajeev Kumar Gupta Ravi Kumar Gundampati Devendra Kumar Singh Sweta Mohan Syed Hadi Hasan Manisha Malviya 《RSC advances》2018,8(2):619
The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). 相似文献
29.
Bharat Lohani Sarvesh Kumar Singh Devendra Choudhary Balasubramanian Nagarajan 《Remote sensing letters.》2018,9(7):636-645
Before installing Photovoltaic (PV) panels at a place it is important to estimate the solar potential of the place. Most approaches available in literature do not consider the presence of surrounding obstructions, thus leading to wrong estimates. Light Detection and Ranging (LiDAR) data or 3D (Geographic Information System) GIS based approaches consider obstructions but prove cost-effective only at city-wide scales. This paper presents a cost-effective, accurate, and scalable approach for this purpose. The proposed approach utilizes terrestrial images of surroundings and identifies obstructions present therein. Using the azimuth and elevation angles of the principal axes of the terrestrial images the azimuth and elevation angles of each pixel in these images are determined. Using thresholding and morphological closing the terrestrial images are segmented into sky and non-sky zones. Sun is considered visible at the point of interest if it lies in the sky zone. The position of the Sun is determined using the solar position algorithm and the irradiance reaching the Earth surface is computed using the modified radiative transfer model. Finally, the total irradiance over a chosen time period at a given location is estimated by integrating the irradiances for the duration when the Sun is visible. 相似文献
30.
Harmanjot?Kaur Shanti?Choudhary Devendra?Pathak Opinder?Singh Ramneek?Verma Ratan?K.?ChoudharyEmail author 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(1):23-32
Water buffaloes are the principle source of milk in south Asia and Africa. Mammary gland repeatedly undergoes the cycles of growth and regeneration during pregnancy, lactation and involution. It is assumed that buffalo mammary gland has mammary stem and progenitor cells that regulate gland growth and regeneration. In the present study the authors analyzed percentage of cellular composition, proliferation status and putative mammary stem/progenitor cell population. Identification of putative buffalo mammary stem/progenitor cells was attempted using immunohistochemical staining with Musashi1 (MSI1), an adult stem cell marker and fibronectin type III domain containing 3B (FNDC3B), a mammary stem and cancer cell marker. Immunolocalization of MSI1 and FNDC3B showed nuclear and cytoplasmic staining of alveolar and ductal mammary epithelial cells (MEC) and a few stromal cells. The percentage of MSI1-positive MEC in non-lactating (3.31 ± 1.11 %), lactating (2.73 ± 0.78 %) and mastitic glands (3.30 ± 0.97 %) were equivalent, indicating that the proportion of putative stem/progenitor cell population did not differ during various physiological stages. Likewise, the percentage of FNDC3B-positive MEC in non-lactating (12.40 ± 3.22 %) tended to be higher than lactating (8.19 ± 2.71 %) and mastitic glands (4.88 ± 2.37 %). In some cases, expression of MSI1 and FNDC3B was exceptionally high with high proliferative indices (37.6 ± 2.4 %)-an indication of tumor cells. This is the first report on expression of MSI1 and FNDC3B in buffalo mammary gland. Identification of buffalo mammary stem cells using MSI1 and FNDC3B requires further studies and functional validation. 相似文献