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排序方式: 共有2698条查询结果,搜索用时 15 毫秒
1.
Patient experience with, and use of, an electronic monitoring system to assess vaccination responses
Stuart S. Olmsted PhD John D. Grabenstein RPh PhD † Arvind K. Jain MS ‡ Nicole Lurie MD MSPH § 《Health expectations》2006,9(2):110-117
OBJECTIVE: To evaluate the user experience and acceptability of an electronic patient monitoring system. SETTING AND PARTICIPANTS: 822 Military and civilian personnel at a health clinic at a major US military headquarters used an Internet and telephone-based electronic monitoring system to report vaccination-site responses and symptoms after receiving the smallpox vaccination. Focus groups of vaccinees were conducted to help develop a survey about the experience that was distributed to 379 vaccinees (96% completion rate). RESULTS: Users of the electronic monitoring system reported that it was fast and easy to use and reported they would use a system like this again and recommend an electronic monitoring system to a friend or relative. Most users (84%) were comfortable with a physician tracking their vaccine reaction using their electronic reports, but only half (51%) were comfortable with eliminating the post-vaccination follow-up visit with their health-care provider based on their electronic reports. CONCLUSIONS: This electronic monitoring system was well received by vaccinees and allowed health-care providers to track the status of vaccinees. However, vaccinees were not comfortable replacing a physician visit with electronic monitoring, at least for the smallpox vaccination. A monitoring system like this may be useful in public health settings, such as mass vaccination or prophylaxis during a bioterrorism event, a pandemic influenza outbreak, or another public health emergency. 相似文献
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Fa-Hsuan Lin Shang-Yueh Tsai Ricardo Otazo Arvind Caprihan Lawrence L Wald John W Belliveau Stefan Posse 《Magnetic resonance in medicine》2007,57(2):249-257
Magnetic resonance spectroscopic imaging (MRSI) provides spatially resolved metabolite information that is invaluable for both neuroscience studies and clinical applications. However, lengthy data acquisition times, which are a result of time-consuming phase encoding, represent a major challenge for MRSI. Fast MRSI pulse sequences that use echo-planar readout gradients, such as proton echo-planar spectroscopic imaging (PEPSI), are capable of fast spectral-spatial encoding and thus enable acceleration of image acquisition times. Combining PEPSI with recent advances in parallel MRI utilizing RF coil arrays can further accelerate MRSI data acquisition. Here we investigate the feasibility of ultrafast spectroscopic imaging at high field (3T and 4T) by combining PEPSI with sensitivity-encoded (SENSE) MRI using eight-channel head coil arrays. We show that the acquisition of single-average SENSE-PEPSI data at a short TE (15 ms) can be accelerated to 32 s or less, depending on the field strength, to obtain metabolic images of choline (Cho), creatine (Cre), N-acetyl-aspartate (NAA), and J-coupled metabolites (e.g., glutamate (Glu) and inositol (Ino)) with acceptable spectral quality and localization. The experimentally measured reductions in signal-to-noise ratio (SNR) and Cramer-Rao lower bounds (CRLBs) of metabolite resonances were well explained by both the g-factor and reduced measurement times. Thus, this technology is a promising means of reducing the scan times of 3D acquisitions and time-resolved 2D measurements. 相似文献
4.
Biochemical changes in the liver of fish, Tilapia mossambica (Peters), during continuous exposure to monocrotophos 总被引:1,自引:0,他引:1
The purpose of the present investigation was to determine the effect of continuous exposure to the organophosphate monocrotophos at 2.5 ppm for over a period of 2 through 45 days on protein, RNA, and DNA contents and on 5'-nucleotidase activity in the liver of Tilapia mossambica. Protein content was decreased by 45% after 5 days, returned to control levels at 10-30 days, and again decreased by 45 days. DNA content was decreased by 2 days, returned to control values by 5 days, and remained constant throughout the exposure. In contrast, RNA content was significantly lower starting from 2 through 45 days of exposure. 5'-Nucleotidase activity showed a transient increase at 5 and 30 days of monocrotophos exposure. These results indicate that monocrotophos altered the protein, DNA, and RNA contents and the 5'-nucleotidase activity levels as early as 2 and 5 days. However, these changes were reversed by 10 days and after a short period of recovery, the alterations reappeared. This supports our earlier histological observations of hepatic pathology during monocrotophos exposure. 相似文献
5.
Garima Chawla Piyush Gupta R Thilagavathi Asit K Chakraborti Arvind K Bansal 《European journal of pharmaceutical sciences》2003,20(3):305-317
This study deals with the generation and characterization of various solid-state forms of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor. The drug was subjected to polymorphic screen using different solvents to explore the possibility of existence of different solid forms. N,N-Dimethyl acetamide (DMA) and N,N-dimethyl formamide (DMF) yielded solvates in 1:1 stoichiometric ratio. Quench cooling of the melt resulted in amorphous form of the drug. All these solid-state forms were characterized by thermoanalytical (DSC, TGA, HSM), crystallographic (XRD), microscopic (polarized, SEM), spectroscopic (FTIR), and elemental analysis techniques. Solubility and van't Hoff studies were carried out for their thermodynamic interpretation. Influence of morphology of different solid-state forms on flow behavior was also investigated. Molecular modeling studies were used to elucidate the interaction between solute and solvent molecules in the solvate. 相似文献
6.
Sequence variation in the envelope E1 and E2 glycoproteins of hepatitis C virus (HCV) could account for differences in disease pathogenesis in patients infected with different genotypes. A cDNA encoding the structural region of the hepatitis C polyprotein was constructed to match the majority sequence of viral RNA extracted from a patient infected with genotype 3a (designated strain HCV3a-Gla). The principal differences predicted between E2 of HCV3a-Gla and the corresponding H77c genotype 1a protein were that the former contained six more amino acids (361 vs. 355), but it had one fewer glycosylation site. Expression studies showed that, in common with the H77c glycoproteins, E1 and E2 from HCV3a-Gla localised to the endoplasmic reticulum (ER) membrane in both Huh-7 and BHK tissue culture cells and interacted to form native complexes. Analysis of the cross-reactivity of antibodies raised against glycoproteins of genotype 1a strains showed that three of five monoclonal antibodies that recognise linear epitopes were able to detect E2 from strain HCV3a-Gla. However, neither conformational E2 antibodies nor antibodies raised against E1 were able to detect the HCV3a-Gla glycoproteins. In receptor binding assays, E2 of HCV3a-Gla consistently failed to bind CD81, a putative cell receptor for HCV. Absence of binding to CD81 and lack of recognition by most antibodies raised to genotype 1a glycoproteins indicate important differences between these glycoproteins representative of genotypes 3a and 1a. These may be pertinent to the differences in response to interferon therapy and the prevalence of steatosis reported in patients infected with these genotypes. 相似文献
7.
Radhika S Bakshi A Rajwanshi A Nijhawan R Das A Kakkar N Joshi K Marwaha RK Rao KL 《Diagnostic cytopathology》2005,32(5):281-286
Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration.Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy. 相似文献
8.
Arvind Kumar Naresh Jindal Chhote L Shukla Rajesh K Asrani David R Ledoux George E Rottinghaus 《Avian pathology》2004,33(4):413-417
A study was conducted to evaluate the effects of ochratoxin A (OA) on Escherichia coli-challenged broiler chickens. One hundred and eighty-four one-day-old broiler chicks were divided into two groups of 92 chicks each, with one group fed a control mash diet and the other fed a mash diet containing 2 parts/10(6) OA. On day 14, each group was further subdivided into two groups with one group inoculated with E. coli O78 (1 x 10(7) colony-forming units/0.5 ml) by the intraperitoneal route, whereas the other group was not inoculated with E. coli. Four birds from each group were sacrificed at 1, 2, 3, 5, 7, 10, 14 and 21 days post-inoculation to record pathological changes in the liver, kidneys, heart, lungs, bursa, spleen and thymus. E. coli infection induced perihepatitis and pericarditis in the liver and heart, respectively, in chickens infected with E. coli alone or in OA-fed birds from 1 day post-infection (DPI) onwards. At 1 DPI, a thin fibrin layer covered the liver and heart; however, at subsequent days, the layer became thicker. E. coli infection did not produce appreciable changes in the kidneys, bursa or thymus. However, there was congestion of the lungs along with mononuclear cell infiltration. Ochratoxin feeding induced changes from 10 DPI onwards in chicks fed OA alone and those infected with E. coli. The changes in kidneys included swollen proximal convoluted tubules, degeneration of tubular epithelium and interstitial nephritis. Degenerative changes and mononuclear cell infiltration were recorded in the liver. There was atrophy of the lymphoid organs along with depletion of lymphocytes. Gross and histopathological changes were more severe in chickens fed OA and inoculated with E. coli than the chickens fed OA alone or those infected with E. coli, indicating combined action of these two. 相似文献
9.
Srikanth Kasturi Arvind Muthirevula Amulya Siddarameshwar Gadennavar Vijay Cholenahalli Lingaraju 《Indian Journal of Thoracic and Cardiovascular Surgery》2021,37(3):338
Penetrating neck trauma, though rare, carries a high morbidity and mortality risk if not recognized promptly, due to the presence of vital neurovascular and airway elements within a closed compartment. We describe the unique presentation of a high zone 1 anterior midline cervical stab injury with bilateral large pneumothoraces and extensive pneumomediastinum. Understanding the respiratory mechanics and a high clinical suspicion will help to recognize such complications of tracheobronchial injuries and their timely management is key to salvage of these patients. 相似文献
10.
Jon Kobashigawa Darshana M. Dadhania Maryjane Farr W. H. Wilson Tang Arvind Bhimaraj Lawrence Czer Shelley Hall Abdolreza Haririan Richard N. Formica Jignesh Patel Rafael Skorka Savitri Fedson Titte Srinivas Jeffrey Testani Julie M. Yabu Xingxing S. Cheng the Consensus Conference Participants 《American journal of transplantation》2021,21(7):2459-2467