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71.
Infodemiology can be defined as the science of distribution and determinants of information in an electronic medium, specifically the Internet, or in a population, with the ultimate aim to inform public health and public policy. Infodemiology data can be collected and analyzed in near real time. Examples for infodemiology applications include: the analysis of queries from Internet search engines to predict disease outbreaks (eg. influenza); monitoring peoples'' status updates on microblogs such as Twitter for syndromic surveillance; detecting and quantifying disparities in health information availability; identifying and monitoring of public health relevant publications on the Internet (eg. anti-vaccination sites, but also news articles or expert-curated outbreak reports); automated tools to measure information diffusion and knowledge translation, and tracking the effectiveness of health marketing campaigns. Moreover, analyzing how people search and navigate the Internet for health-related information, as well as how they communicate and share this information, can provide valuable insights into health-related behavior of populations. Seven years after the infodemiology concept was first introduced, this paper revisits the emerging fields of infodemiology and infoveillance and proposes an expanded framework, introducing some basic metrics such as information prevalence, concept occurrence ratios, and information incidence. The framework distinguishes supply-based applications (analyzing what is being published on the Internet, eg. on Web sites, newsgroups, blogs, microblogs and social media) from demand-based methods (search and navigation behavior), and further distinguishes passive from active infoveillance methods. Infodemiology metrics follow population health relevant events or predict them. Thus, these metrics and methods are potentially useful for public health practice and research, and should be further developed and standardized. 相似文献
72.
Tuon and colleagues have developed an animal model to examine the impact of sepsis on memory in rats. They report important
data that expand the understanding of the cognitive consequences of critical illness. Future research should follow this path
of inquiry and extend animal models beyond aversive conditioning to include recently developed paradigms that will permit
assessment of complex and cognitive processes, such as attention, episodic memory and orientation to time and place. This
has the potential to greatly increase the putative understanding of the homologous neurocognitive dysfunctions acquired during
critical illness. 相似文献
73.
Florian Gras Ivan Marintschev David M. Kahler Kajetan Klos Thomas M��ckley Gunther O. Hofmann 《Knee surgery, sports traumatology, arthroscopy》2011,19(1):55-59
Purpose
Retrograde drilling of osteochondral lesions (OCLs) is a recommended, but demanding operative approach for revascularization of lesions in stage 1–3 according to Berndt and Harty after failed conservative treatment. The gold standard of intraoperative driller guidance is fluoroscopic control. Limitations are a 2D visualization of a 3D procedure and sometimes limited view of the OCL in fluoroscopy, leading to increased radiation exposure. A new image-free navigation procedure was evaluated for practicability and precision in first clinical applications. 相似文献74.
Blythe A. Corbett Joan R. Gunther Dan Comins Jenifer Price Niles Ryan David Simon Clayton W. Schupp Taylor Rios 《Journal of autism and developmental disorders》2011,41(4):505-511
The pilot investigation evaluated a theatrical intervention program, Social Emotional NeuroScience Endocrinology (SENSE) Theatre,
designed to improve socioemotional functioning and reduce stress in children with autism spectrum disorder (ASD). Eight children
with ASD were paired with typically developing peers that served as expert models. Neuropsychological, biological (cortisol
and oxytocin), and behavioral measures were assessed in a pretest–posttest design. The intervention was embedded in a full
musical theatrical production. Participants showed some improvement in face identification and theory of mind skills. The
intervention shows potential promise in improving the socioemotional functioning in children with ASD through the utilization
of peers, video and behavioral modeling, and a community-based theatrical setting. 相似文献
75.
Raffaele Nardone Jürgen Bergmann Martin Kronbichler Francesca Caleri Piergiorgio Lochner Frediano Tezzon Gunther Ladurner Stefan Golaszewski 《Alcoholism, clinical and experimental research》2010,34(4):628-632
Background: Alcohol addiction is a complex brain disease caused by alterations in crucial neurotransmitter systems, including gamma‐aminobutyric acid (GABA) and glutamate. These disturbances could be revealed by changes in cortical excitability parameters, as assessed by transcranial magnetic stimulation (TMS). This study was aimed to further investigate the complex pathophysiology of alcohol withdrawal syndrome (AWS). Methods: Motor cortex excitability was examined in 13 subjects with AWS in a mild predelirial state, in 12 chronic alcoholics and in 15 age‐matched control subjects, using a range of TMS protocols. Central motor conduction time, resting and active motor threshold, duration of the cortical silent period, short latency intracortical inhibition (SICI), and intracortical facilitation (ICF) to paired TMS were examined. Results: Intracortical facilitation was significantly increased in the AWS patients when compared with the chronic alcoholics and the control subjects. The other TMS parameters did not differ significantly from the controls. Administration of a single oral dose of the glutamatergic antagonist riluzole in a subgroup of 8 patients significantly reduced ICF; motor threshold and SICI were not affected by riluzole. Conclusion: Transcranial magnetic stimulation shows a selective increase in intracortical facilitation after ethanol withdrawal. Our findings support the theory that altered glutamatergic receptor function plays an important role in the pathogenesis of human alcohol withdrawal. This study provides further physiological evidence that antiglutamatergic approaches represent an efficacious alternative for treating alcohol withdrawal symptoms. 相似文献
76.
Ute E Krainick-Strobel Werner Lichtenegger Diethelm Wallwiener Augustinus H Tulusan Fritz Jänicke Gunther Bastert Ludwig Kiesel Birgit Wackwitz Stefan Paepke 《BMC cancer》2008,8(1):62
Background
In recent years, preoperative volume reduction of locally advanced breast cancers, resulting in higher rates of breast-conserving surgery (BCS), has become increasingly important also in postmenopausal women. Clinical interest has come to center on the third-generation nonsteroidal aromatase inhibitors (AIs), including letrozole, for such neoadjuvant endocrine treatment. This usually lasts 3–4 months and has been extended to up to 12 months, but optimal treatment duration has not been fully established. 相似文献77.
C Sohn W Stolz E M Grischke D Wallwiener G Bastert D von Fournier 《Zentralblatt für Gyn?kologie》1992,114(5):249-253
The preoperative examinations by doppler-sonography of 83 patients with tumors of the breast are presented. The examinations are done with newest technique: duplex-sonography in slow-flow-technique (AI 3200, Dornier); colour-sonography in MEM-technique (AI 5200, Dornier) and synchronical colour-doppler++ (Quantum 2000, Siemens) and CW-doppler-sonography (Vasocope 3, Kranzbühler). There is a markable difference between the side of carcinoma and the normal side as well as pre- and postmenopausal patients. No difference is shown in cases of benign tumors and the normal side. The increasing blood flow of a malignant tumor is showed in changing the doppler parameters (A/B-ratio and resistance-index) and in the doppler wave form. The number of vessels found in or around a tumor is not a good criteria to find malignant diseases, the best criteria is the difference between sides of the mamma. 相似文献
78.
The quenching of the Y(D) tyrosyl radical in photosystem II by nitric oxide was reported to result from the formation of a weak tyrosyl radical-nitric oxide complex. This radical/radical reaction is expected to generate an electron spin resonance (ESR)-silent nitrosocyclohexadienone species that can reversibly regenerate the tyrosyl radical and nitric oxide or undergo rearrangement to form 3-nitrosotyrosine. It has been proposed that 3-nitrosotyrosine can be oxidized by one electron to form the tyrosine iminoxyl radical (>C=N-O.). This proposal was put forth as a result of ESR detection of the iminoxyl radical intermediate when photosystem II was exposed to nitric oxide. Although the detection of the iminoxyl radical in photosystem II strongly suggested a mechanism involving 3-nitrosotyrosine, the iminoxyl radical ESR spectrum was not unequivocally identified as originating from tyrosine. Subsequently, non-protein L-tyrosine iminoxyl radical was generated by two methods: (1) peroxidase oxidation of synthetic 3-nitroso-N-acetyl-L-tyrosine; and (2) peroxidase oxidation of free L-tyrosine in the presence of nitric oxide. The determination of protein nitrotyrosine content has become a frequently used technique for the detection of nitrosative tissue damage. Protein nitration has been suggested to be a final product of the production of highly reactive nitrogen oxide intermediates (e.g. peroxynitrite) formed in reactions between nitric oxide (NO.) and oxygen-derived species such as superoxide. The enzyme prostaglandin H synthase-2 also forms a tyrosyl radical during its enzymatic catalysis of prostaglandin formation. In the presence of the NO.-generator diethylamine nonoate, the tyrosyl radical of prostaglandin H synthase-2 also changes to that of an iminoxyl radical. Western blot analysis of prostaglandin H synthase-2 after exposure to the NO.-generator revealed nitrotyrosine formation. The results provide a mechanism for nitric oxide-dependent tyrosine nitration that does not require formation of more highly reactive nitrogen oxide intermediates such as peroxynitrite or nitrogen dioxide. 相似文献
79.
Shvedova AA Kisin ER Murray AR Kommineni C Castranova V Mason RP Kadiiska MB Gunther MR 《Chemical research in toxicology》2002,15(11):1451-1459
Organic peroxides are widely used in the chemical industry as initiators of oxidation for the production of polymers and fiber-reinforced plastics, in the manufacture of polyester resin coatings, and pharmaceuticals. Free radical production is considered to be one of the key factors contributing to skin tumor promotion by organic peroxides. In vitro experiments have demonstrated metal-catalyzed formation of alkoxyl, alkyl, and aryl radicals in keratinocytes incubated with cumene hydroperoxide. The present study investigated in vivo free radical generation in lipid extracts of mouse skin exposed to cumene hydroperoxide. The electron spin resonance (ESR) spin-trapping technique was used to detect the formation of alpha-phenyl-N-tert-butylnitrone (PBN) radical adducts, following intradermal injection of 180 mg/kg PBN. It was found that 30 min after topical exposure, cumene hydroperoxide (12 mmol/kg) induced free radical generation in the skin of female Balb/c mice kept for 10 weeks on vitamin E-deficient diets. In contrast, hardly discernible radical adducts were detected when cumene hydroperoxide was applied to the skin of mice fed a vitamin E-sufficient diet. Importantly, total antioxidant reserve and levels of GSH, ascorbate, and vitamin E decreased 34%, 46.5%. 27%, and 98%, respectively, after mice were kept for 10 weeks on vitamin E-deficient diet. PBN adducts detected by ESR in vitamin E-deficient mice provide direct evidence for in vivo free radical generation in the skin after exposure to cumene hydroperoxide. 相似文献
80.
OBJECTIVE: To compare power Doppler sonography (PDS) findings inside the bicipital tendon sheath in patients with rheumatoid arthritis (RA) and degenerative disorders of the shoulder, in order to evaluate the diagnostic value of PDS in distinguishing between inflammatory and noninflammatory shoulder pain. METHODS: The glenohumeral joints of 41 consecutive patients with shoulder pain were examined by ultrasound. Using ventral transverse and longitudinal scanning, the vascularity near and/or inside the bicipital tendon sheath was visualized by PDS. One fully trained and experienced examiner performed the sonography. Representative images were digitally stored and were read, under blinded conditions, by 2 independent investigators, who categorized the Doppler signals as being either inside or outside the tendon sheath. RESULTS: Biceps tendon sheath effusion, represented by the typical hypoechoic rim, was found in 95.8% of the RA patients (23 of 24) and in 58.8% of the patients with degenerative disorders (10 of 17). PDS signals were localized to inside the tendon sheath in 22 of the RA patients (91.7%) and in none of the patients with degenerative disorders. Although no PDS signal was found inside the tendon sheath in patients with degenerative disorders, in 9 of these patients (52.9%), signals could be localized to the environment of the tendon sheath. CONCLUSION: PDS demonstrates vascularity in the long bicipital tendon sheath of patients with RA, but not in those with degenerative shoulder disorders. 相似文献