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991.
Park WT O'Connor KN Chen KL Mallon JR Maetani T Dalal P Candler RN Ayanoor-Vitikkate V Roberson JB Puria S Kenny TW 《Biomedical microdevices》2007,9(6):939-949
Experiments were conducted to evaluate a silicon accelerometer as an implantable sound sensor for implantable hearing aids.
The main motivation of this study is to find an alternative sound sensor that is implantable inside the body, yet does not
suffer from the signal attenuation from the body. The merit of the accelerometer sensor as a sound sensor will be that it
will utilize the natural mechanical conduction in the middle ear as a source of the vibration. With this kind of implantable
sound sensor, a totally implantable hearing aid is feasible. A piezoresistive silicon accelerometer that is completely encapsulated
with a thin silicon film and long flexible flex-circuit electrical cables were used for this study. The sensor is attached
on the middle ear ossicles and measures the vibration transmitted from the tympanic membrane due to the sound in the ear canal.
In this study, the sensor is fully characterized on a human cadaveric temporal bone preparation.
Earlier portion of the work in this paper was presented at the 13th International Conference on Solid-State Sensors, Actuators
and Microsystems (Transducers) 2005, Seoul Korea. 相似文献
992.
Okoye FI Krishnan S Chandok MR Tsokos GC Farber DL 《Clinical immunology (Orlando, Fla.)》2007,125(1):5-15
The functional coupling of T cell receptor (TCR)-mediated signaling events in primary human T cells remains undefined. We demonstrate here that alterations in the expression of proximal TCR-coupled signaling subunits are associated with distinct effector capacities in differentiated human CD4 T cells. Analysis of proximal signaling profiles using biochemical and single cell approaches reveals decreased CD3zeta and ZAP-70 expression correlating with functional anergy, with increased CD3zeta/ ZAP-70 expression and phosphorylation connoting acquisition of effector capacity. By contrast, the FcRgamma signaling subunit known to be expressed in human effector cells and in T cells from the autoimmune disease SLE is up-regulated upon activation, yet does not correlate with functional capacity in effector cells, and does not alter signaling or function in primary FcRgamma transfectants. Our results have implications for targeting signaling molecules in immunotherapy and evaluating the functional consequence of signaling alterations associated with autoimmunity and chronic diseases. 相似文献
993.
Kunik ME Azzam PN Souchek J Cully JA Wray NP Krishnan LL Nelson HA Stanley MA 《Psychosomatics》2007,48(1):16-21
Obstructive lung diseases are associated with high rates of depression and anxiety, yet many patients are never screened or treated. This study evaluated the five-question Depression and Anxiety modules of the Primary Care Evaluation of Mental Disorders (PRIME-MD) Patient Questionnaire as a telephone screen in 1,632 patients with chronic breathing disorders at a Veterans Affairs Medical Center in Houston, TX. Subsequent testing of 828 patients with the Beck Depression Inventory-II and the Beck Anxiety Inventory showed that the sensitivity and specificity, respectively, of the Depression and Anxiety modules of the PRIME-MD Patient Questionnaire screening were 94.6% and 49.5% (Depression); 93.7% and 32.2% (Anxiety); and 97.7%, and 36.0% (combined screen), with an overall accuracy of 80.7%. In such populations, these two modules of the PRIME-MD Patient Questionnaire may be a useful screening tool. 相似文献
994.
Kannathasan K Senthilkumar A Chandrasekaran M Venkatesalu V 《Parasitology research》2007,101(6):1721-1723
The early fourth instar larvae of Culex quinquefasciatus, reared in the laboratory were used for larvicidal assay with leaf extracts of Vitex negundo, Vitex trifolia, Vitex peduncularis and Vitex altissima. The methanol extracts of the four species possessed varying levels of larvicidal nature. The highest larvicidal activity
was found with the extract of V. trifolia (LC50 = 41.41 ppm) followed by V. peduncularis (LC50 = 76.28 ppm), V. altissima (LC50 = 128.04 ppm) and V. negundo (LC50 = 212.57 ppm). 相似文献
995.
Sazawal S Dhingra U Deb S Bhan MK Menon VP Black RE 《Journal of health, population, and nutrition》2007,25(1):62-66
In a community-based double-blind randomized trial in children aged 6-35 months, both intervention and control groups received a multi-vitamin syrup containing vitamin A, while the intervention group had zinc gluconate (equivalent to 10 mg of elemental zinc) additional in the syrup. There was a significant decrease in diarrhoea and pneumonia in the intervention group. This study was undertaken to investigate if addition of zinc to vitamin A had improved plasma retinol levels, which, in turn, was responsible for the effects observed in the intervention group. In a randomly-selected subsample of 200 children--100 each from the intervention and the control group, plasma retinol levels after 120 days of supplementation were measured. There was no difference in the mean plasma retinol levels [the difference in the mean 0.46 microg/dL (95% confidence interval -1.42-2.36)] between the two groups following supplementation. No difference in plasma retinol levels was observed in the subgroups based on base-line nutritional status and plasma zinc levels. Addition of zinc to low-dose vitamin A in this study did not improve the vitamin A status of children and cannot explain morbidity effects of the intervention. 相似文献
996.
Singhal S Purnapatre KP Kalia V Dube S Nair D Deb M Aggarwal P Gupta S Upadhyay DJ Rattan A Raj VS 《Emerging infectious diseases》2007,13(10):1614-1616
Decreased susceptibility of Neisseria meningitidis isolates to ciprofloxacin emerged from an outbreak in Delhi, India. Results of antimicrobial susceptibility testing of the meningococcal isolates to ciprofloxacin and further sequencing of DNA gyrase A quinolone-resistance-determining region confirmed the emergence of ciprofloxacin resistance in the outbreak. 相似文献
997.
998.
Sukhmani K. Padda Yesim Gkmen-Polar Jessica A. Hellyer Sunil S. Badve Neeraj K. Singh Sumanth M. Vasista Kabya Basu Ansu Kumar Heather A. Wakelee 《Oncotarget》2021,12(12):1178
Further characterization of thymic epithelial tumors (TETs) is needed. Genomic information from 102 evaluable TETs from The Cancer Genome Atlas (TCGA) dataset and from the IU-TAB-1 cell line (type AB thymoma) underwent clustering analysis to identify molecular subtypes of TETs. Six novel molecular subtypes (TH1-TH6) of TETs from the TCGA were identified, and there was no association with WHO histologic subtype. The IU-TAB-1 cell line clustered into the TH4 molecular subtype and in vitro testing of candidate therapeutics was performed. The IU-TAB-1 cell line was noted to be resistant to everolimus (mTORC1 inhibitor) and sensitive to nelfinavir (AKT1 inhibitor) across the endpoints measured. Sensitivity to nelfinavir was due to the IU-TAB-1 cell line’s gain-of function (GOF) mutation in PIK3CA and amplification of genes observed from array comparative genomic hybridization (aCGH), including AURKA, ERBB2, KIT, PDGFRA and PDGFB, that are known upregulate AKT, while resistance to everolimus was primarily driven by upregulation of downstream signaling of KIT, PDGFRA and PDGFB in the presence of mTORC1 inhibition. We present a novel molecular classification of TETs independent of WHO histologic subtype, which may be used for preclinical validation studies of potential candidate therapeutics of interest for this rare disease. 相似文献
999.
Pradhan S Yadav R Mishra VN 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2007,101(1):25-33
We evaluated the clinical and imaging features of cranial toxoplasmosis in patients without HIV infection. Between 1995 and 2005, 15 patients with serologically proven cranial toxoplasmosis were selected for clinical and imaging study from 233 patients with chronic meningitis and 364 patients with seizures/psychosis. All patients had poor immune status due to nutritional and metabolic causes. Neurological presentations included focal encephalitis, multifocal encephalitis and diffuse meningoencephalitis. The three groups had distinct symptoms and imaging features, with some overlap. Magnetic resonance imaging showed single or multiple nodular or ring-enhancing lesions often at the grey-white junction with subcortical white matter perifocal oedema. Within the large diffuse lesions there were discrete small haemorrhagic lesions and contrast medium administration showed fine-beaded parallel lines or small discrete nodules traversing the white matter suggesting perivenous spread. Complete clinical recovery was noted in 12 patients after several 6-week courses of pyrimethamine and sulfonamide/clindamycin. Five patients required two such courses, three patients required three courses, three patients required five courses and two patients required six courses for the final radiological healing, which was complete in nine patients. One patient was lost to follow-up and one patient died of cardiomyopathy. Knowledge of these three distinct initial presentations may help in the early diagnosis of cranial toxoplasmosis in HIV-seronegative patients. Prognosis in early cases is generally good but complete recovery may need several courses of treatment. 相似文献