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排序方式: 共有621条查询结果,搜索用时 15 毫秒
21.
Chong SK Lou Q Zollinger TW Rabinowitz S Jibaly R Tolia V Elitsur Y Gold BD Rosenberg A Johnson A Elkayam O Rosenthal P Gilger M Li BU Peacock JS 《The American journal of gastroenterology》2003,98(10):2162-2168
OBJECTIVES: The purpose of this study was to determine the prevalence of serum antibodies directed against Helicobacter pylori (H. pylori) in children referred to children's hospitals or medical centers throughout the United States. METHODS: This multisite cross-sectional prospective study involved 992 children from 12 states using a validated anti-H. pylori IgG enzyme immunoassay. The children were recruited into two groups: those without any GI complaints (non-GI referral, n = 619) and those who were referred for endoscopy because of abdominal pain (GI referral, n = 373). RESULTS: GI referral children had a higher rate of seropositivity (22.5%) than non-GI referral children (14.1%) from the same geographic regions. In both groups, older children were more likely to be seropositive for H. pylori, as were nonwhite children and those with lower socioeconomic status. H. pylori seropositivity rates were higher in GI referral children with four or more household members (relative risk [RR] = 1.47; CI 1.01-2.14). Multivariate analysis controlling for age, ethnicity, and household income, showed that presence of GI symptoms were associated with a nearly 2-fold risk for H. pylori seropositivity (odds ratio = 1.77, CI 1.27-2.47). Epigastric pain (RR = 2.21; CI = 1.33-3.66) and having three or more episodes of abdominal pain in the last 3 months (RR = 0.59, CI = 0.35-0.99) were the only specific symptoms significantly associated with H. pylori seropositivity. CONCLUSIONS: The H. pylori seropositivity rate of GI referral children with symptoms of abdominal pain was significantly higher. H. pylori infection in early childhood was found to be associated primarily with the child's household size and socioeconomic status. 相似文献
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Jay R. Dave Ankush M. Dewle Suhas T. Mhaske Prashant T. Phulpagar Vikas L. Mathe Supriya E. More Ayesha A. Khan Appala Venkata Ramana Murthy Suwarna S. Datar Ajay J. Jog Megha Page Geetanjali B. Tomar 《Nanomedicine : nanotechnology, biology, and medicine》2019,15(1):218-230
Parathyroid hormone (PTH) has been a major contributor to the anabolic therapy for osteoporosis, but its delivery to bone without losing activity and avoiding adverse local effects remain a challenge. Being the natural component of bone, use of hydroxyapatite for this purpose brings a major breakthrough in synergistic anabolism. This study focuses on synthesis, characterization and evaluation of in vitro and in vivo efficacy of PTH (1-34) adsorbed hydroxyapatite nanocarrier for synergistic enhancement in the anabolic activity of PTH for bone regeneration. The negative zeta potential of this nanocarrier facilitated its affinity to the Ca2+ rich bone tissue and solubilization at low pH enhanced specific delivery of PTH to the resorption pits in osteoporotic bone. In this process, PTH retained its anabolic effect and at the same time an increase in bone mineral content indicated enhancement of the net formative effect of the PTH anabolic therapy. 相似文献
23.
Venkanna Balaganur Nitya Nand Pathak Madhu C. Lingaraju Amar Sunil More Najeeb Latief Rashmi Rekha Kumari 《Connective tissue research》2014,55(5-6):367-377
The aim of the present study was to evaluate in vivo modulatory effect of S-methylisothiourea (SMT), a preferential inhibitor of inducible nitric oxide synthase (iNOS) on pain and pathology in the surgical model of osteoarthritis (OA) in rats. The OA was produced by the anterior cruciate ligament transection (ACLT) and medial meniscectomy (MMx) of right knee. SMT was administered 1 day prior to the production of OA and continued up to day 42 postoperation. Mechanical hyperalgesia, thermal hyperalgesia, tail flick latency after repeated flexion and extension of OA knee and knee diameter of right knee were determined at weekly intervals. Serum levels of IL-1β, TNF-α and nitrite concentration were determined at the end of the experiment. Glycosaminoglycan (GAG) content, collagen content and histopathological evaluation of articular cartilage were also determined at the end of the experiment. SMT reduced mechanical hyperalgesia and the serum levels of IL-1β, TNF-α and nitrite. Further, SMT reduced the loss of GAG from articular cartilage. Microscopically, SMT reduced the severity of the cartilage lesion. The results indicate the effectiveness of SMT in attenuating the pain and pathology of experimental OA phase by reducing the production of nitric oxide and interleukin-1β and tumor necrosis factor-α, which are known to play a major role in the pathophysiology of OA. 相似文献
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Kavalipurapu Venkata Teja Sindhu Ramesh Gopi Battineni Kaligotla Apoorva Vasundhara Jerry Jose Krishnamachari Janani 《Saudi Dental Journal》2022,34(2):87-99
BackgroundFluid dynamics is a majorly neglected aspect to be studied in root canal irrigation. The fundamental rule to understand mechanics is to observe patterns of flow during the process. Thus, this work is conducted to do a systemic assessment of the in-vitro and ex-vivo based studies to evaluate the effect of various parameters on the irrigant flow and apical pressure on using a manual syringe needle for root canal irrigation.MethodsThe literature search was conducted through libraries such as PubMed (Medline), CINAHL, Embase, Scopus and other hand literature from Google Scholar, the British medical library etc. The systematic review was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. As they include studies that were in-vitro and ex-vivo based, the risk of bias of the selected articles was assessed using a customized tool based on the previous literature and parameters evaluated in the studies included.ResultsThe literature search resulted in 101 items of which 19 records were included in this review. Results reported that multiple factors and parameters were assessed to evaluate the flow and apical pressures on using manual syringe needle irrigation.ConclusionsPresent systematic review gives insights in-depth about the irrigation dynamics of manual syringe needle irrigation. Besides, it is inconclusive to compile a single factor or a single parameter contributing to the enhanced irrigant flow and least apical pressures. 相似文献
27.
Vikas Sinha Rizwan Memon Devang Gupta Bela Prajapati Vadisha Bhat Yogesh More 《Indian journal of otolaryngology and head and neck surgery》2007,59(3):211-214
Inhalation of foreign body into the tracheobronchial tree is a medical emergency sometimes resulting into sudden death. The current mortality rate due to foreign body inhalation ranges from 0% to 1.8%. Children with or without positive history of aspiration were examined and diagnosis was made on the basis of history, clinical findings, radiological evaluation and strong index of suspicion. A review of 30 cases of suspected foreign body aspiration revealed, children between 6 months were found to be very vulnerable to aspiration. Majority of children were boys. 80% of the patients had positive history of inhalation. Only 50% of the patients presented immediately i.e. within 24 hours after aspiration. Common symptoms were cough and respiratory distress. Decreased air entry was the significant clinical sign (50%). Obstructive emphysema and mediastinal shift were found in the majority of cases (50%). Rigid bronchoscopy under general anaesthesia and patient ventilating using a jet ventilator is a very safe and effective technique. 相似文献
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The novel antagonist 3-CBW discriminates between kainate receptors expressed on neonatal rat motoneurones and those on dorsal root C-fibres 下载免费PDF全文
1. The natural product willardiine is a selective AMPA receptor agonist. We report that an N(3)-substituted analogue of willardiine, (S)-3-(4-carboxybenzyl)willardiine 3-CBW, antagonizes AMPA and kainate receptors expressed on motoneurones and dorsal root C-fibres, respectively. 2. Reduction of the fast component of the dorsal root-evoked ventral root potential (fDR-VRP) has been used as a novel method to compare AMPA receptor antagonists. 3-CBW, NBQX and GYKI53655 depressed the fDR-VRP with IC(50) values of 10.3+/-2.4, 0.214+/-0.043 and 4.03+/-0.31 micro M, respectively. That 3-CBW depressed the fDR-VRP by acting at AMPA and not metabotropic glutamate receptors was demonstrated by the lack of effect of LY341495 (100 micro M). 3. The Schild plot for antagonism of responses to (S)-5-fluorowillardiine on motoneurones by 3-CBW had a slope of 1.11+/-0.13 giving a pA(2) value of 4.48. The Schild plot for antagonism of kainate responses on the dorsal root by 3-CBW had a slope of 1.05+/-0.05 giving a pA(2) value of 4.96. 4. On neonatal rat motoneurones 3-CBW (200 micro M) almost completely abolished responses to AMPA while responses to NMDA, kainate and DHPG were 101.6+/-11.6%, 39.4+/-5.8% and 110.5+/-9.0% of control, respectively. 3-CBW can therefore be used to isolate kainate receptor responses from those mediated by AMPA receptors. 5 3-CBW antagonized kainate-induced responses on dorsal root C-fibres with a pA(2) value of 4.96 whereas kainate receptor mediated responses (isolated by including GYKI53655 in the medium) on motoneurones were not completely blocked by 200 micro M 3-CBW, substantiating evidence that kainate receptors on neonatal rat motoneurones differ from those on dorsal root C-fibres. 相似文献
30.
Williams MB More MJ Narayanan D Majewski S Weisenberger AG Wojcik R Stanton M Phillips W Stewart A 《Technology in cancer research & treatment》2002,1(1):39-42
Scintimammography, or single gamma nuclear imaging of the breast, has shown promise as a way of characterizing certain biological properties of suspicious breast masses. Conventional scintimammography, performed using large clinical gamma cameras and prone patient positioning suffers from several drawbacks including poor sensitivity for small (> 1 cm) lesions and no reliable method for correlating scintigraphic findings with those of other imaging modalities. We are developing a system designed to overcome some of these problems. The system combines x-ray mammography with scintimammography on a common gantry. The x-ray and gamma ray images are obtained in quick succession, with the breast in a common configuration under mild compression. A digital x-ray detector is used, permitting rapid assessment of lesion location prior to gamma imaging, and enabling fusion of the x-ray transmission and gamma emission information in a single digital image. In a pilot clinical diagnostic study, the system has demonstrated high pathology-proven accuracy in differentiating benign and malignant masses. 相似文献