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81.
Kwon MS Vorobyev V K?nn?l? S Laine M Rinne JO Toivonen T Johansson J Ter?s M Lindholm H Alanko T H?m?l?inen H 《Journal of cerebral blood flow and metabolism》2011,31(12):2293-2301
We investigated the effects of mobile phone radiation on cerebral glucose metabolism using high-resolution positron emission tomography (PET) with the (18)F-deoxyglucose (FDG) tracer. A long half-life (109 minutes) of the (18)F isotope allowed a long, natural exposure condition outside the PET scanner. Thirteen young right-handed male subjects were exposed to a pulse-modulated 902.4 MHz Global System for Mobile Communications signal for 33 minutes, while performing a simple visual vigilance task. Temperature was also measured in the head region (forehead, eyes, cheeks, ear canals) during exposure. (18)F-deoxyglucose PET images acquired after the exposure showed that relative cerebral metabolic rate of glucose was significantly reduced in the temporoparietal junction and anterior temporal lobe of the right hemisphere ipsilateral to the exposure. Temperature rise was also observed on the exposed side of the head, but the magnitude was very small. The exposure did not affect task performance (reaction time, error rate). Our results show that short-term mobile phone exposure can locally suppress brain energy metabolism in humans. 相似文献
82.
Petro Julkunen Esa P. Halmesmäki Jarkko Iivarinen Lassi Rieppo Tommi Närhi Juho Marjanen Jarno Rieppo Jari Arokoski Pieter A. Brama Jukka S. Jurvelin Heikki J. Helminen 《Journal of anatomy》2010,217(3):262-274
Articular cartilage composition and structure are maintained and remodeled by chondrocytes under the influence of loading. Exercise‐induced changes in the composition, structure, mechanical properties and tissue integrity of growing and aging hamster articular cartilage were investigated. Articular cartilage samples (n = 191) were harvested from the proximal tibiae of hamsters aged 1, 3, 6, 12 and 15 months. The hamsters were divided into runners and controls. The runners had free access to a running wheel between 1 and 3 months (runner groups 3‐, 12‐ and 15‐month‐old hamsters) or 1 and 6 months (runner group 6‐month‐old hamsters) of age. Control animals were subjected to a sedentary lifestyle. Mechanical indentation tests and depth‐wise compositional and structural analyses were performed for the cartilage samples. Furthermore, the integrity of articular cartilage was assessed using histological osteoarthritis grading. Exercise affected the collagen network organization after a 5‐month exercise period, especially in the middle and deep zones. However, no effect on the mechanical properties was detected after exercise. Before the age of 12 months, the runners showed less osteoarthritis than the controls, whereas at 15 months of age the situation was reversed. It is concluded that, in hamsters, physical exercise at a young age enhances cartilage maturation and alters the depth‐wise cartilage structure and composition. This may be considered beneficial. However, exercise at a young age demonstrated adverse effects on cartilage at a later age with a significant increase in the incidence of osteoarthritis. 相似文献
83.
84.
Tommi L. Gaines Julia T. Caldwell Chandra L. Ford Mesfin S. Mulatu Dionne C. Godette 《AIDS care》2016,28(5):554-560
The Centers for Disease Control and Prevention's (CDC) expanded testing initiative (ETI) aims to bolster HIV testing among populations disproportionately affected by the HIV epidemic by providing additional funding to health departments serving these communities. ETI prioritizes testing in clinical settings; therefore, we examined the relationship between state-level ETI participation and past-year HIV testing among a racially/ethnically diverse sample of adult respondents to the 2012 Behavioral Risk Factor Surveillance System who accessed health services within the 12 months prior to being interviewed. Controlling for individual- and state-level characteristics in a multilevel logistic regression model, ETI participation was independently and positively associated with past-year testing, but this association varied by race/ethnicity. Hispanics had higher odds (adjusted odds ratio [AOR]: 1.49; 95% CI: 1.11–2.02) and American Indian/Alaska Natives had lower odds (AOR: 0.66; 95% CI: 0.43–0.99) of testing if they resided in states with (vs. without) ETI participation. State-level ETI participation did not significantly alter past-year testing among other racial/ethnic groups. Prioritizing public health resources in states most affected by HIV can improve testing patterns, but other mechanisms likely influence which racial/ethnic groups undergo testing. 相似文献
85.
Tommi Kumpulainen Mari Sandell Pasi Junell Anu Hopia 《Journal of Culinary Science & Technology》2016,14(2):153-165
The purpose of this research was to study how consumers respond to differences in the freshness of lettuce based only on sensory properties in the foodservice context. Another objective was to measure consumer response to the modification of the consumption context. Data was collected from consumer studies in two separate restaurants with three different products (n = 238). The reference sample was a packaged ready-to-eat lettuce, which was compared using two freshly prepared samples. The results indicated that consumers did recognize differences between product properties that depend on the level of freshness when served in a foodservice environment. By serving fresh products, the perceived level of sensory quality showed a significant increase. 相似文献
86.
Tommi Anttonen Ilya Belevich Anna Kirjavainen Maarja Laos Cord Brakebusch Eija Jokitalo Ulla Pirvola 《Journal of the Association for Research in Otolaryngology》2014,15(6):975-992
Hair cell death is a major cause of hearing impairment. Preservation of surface barrier upon hair cell loss is critical to prevent leakage of potassium-rich endolymph into the organ of Corti and to prevent expansion of cellular damage. Understanding of wound healing in this cytoarchitecturally complex organ requires ultrastructural 3D visualization. Powered by the serial block-face scanning electron microscopy, we penetrate into the cell biological mechanisms in the acute response of outer hair cells and glial-like Deiters’ cells to ototoxic trauma in vivo. We show that Deiters’ cells function as phagocytes. Upon trauma, their phalangeal processes swell and the resulting close cellular contacts allow engulfment of apoptotic cell debris. Apical domains of dying hair cells are eliminated from the inner ear sensory epithelia, an event thought to depend on supporting cells’ actomyosin contractile activity. We show that in the case of apoptotic outer hair cells of the organ of Corti, elimination of their apices is preceded by strong cell body shrinkage, emphasizing the role of the dying cell itself in the cleavage. Our data reveal that the resealing of epithelial surface by junctional extensions of Deiters’ cells is dynamically reinforced by newly polymerized F-actin belts. By analyzing Cdc42-inactivated Deiters’ cells with defects in actin dynamics and surface closure, we show that compromised barrier integrity shifts hair cell death from apoptosis to necrosis and leads to expanded hair cell and nerve fiber damage. Our results have implications concerning therapeutic protective and regenerative interventions, because both interventions should maintain barrier integrity. 相似文献
87.
Eskelinen Tommi Veitonmäki Thea Kotsar Andres Tammela Teuvo L. J. Pöyhönen Antti Murtola Teemu J. 《Cancer causes & control : CCC》2022,33(2):313-320
Cancer Causes & Control - We explored renal cell cancer (RCC) survival among users of antihypertensive medication as hypertension is proposed to be a risk factor for RCC and ACE-inhibitors and... 相似文献
88.
Lin FH Tsai KW Chu YH Witzel T Nummenmaa A Raij T Ahveninen J Kuo WJ Belliveau JW 《NeuroImage》2012,62(2):699-705
Inverse imaging (InI) supercharges the sampling rate of traditional functional MRI 10-100 fold at a cost of a moderate reduction in spatial resolution. The technique is inspired by similarities between multi-sensor magnetoencephalography (MEG) and highly parallel radio-frequency (RF) MRI detector arrays. Using presently available 32-channel head coils at 3T, InI can be sampled at 10 Hz and provides about 5-mm cortical spatial resolution with whole-brain coverage. Here we discuss the present applications of InI, as well as potential future challenges and opportunities in further improving its spatiotemporal resolution and sensitivity. InI may become a helpful tool for clinicians and neuroscientists for revealing the complex dynamics of brain functions during task-related and resting states. 相似文献
89.
Jukka Hintikka Leo Niskanen Heli Koivumaa-Honkanen Tommi Tolmunen Kirsi Honkalampi Soili M. Lehto Heimo Viinamäki 《The journal of sexual medicine》2009,6(7):2049-2057
IntroductionIn middle-aged men, the associations between long-term depressive symptoms and circulating testosterone levels are poorly known, although it is known that testosterone levels decrease with age.MethodsA health questionnaire was mailed to a population-based sample from the National Population Register in 1998, 1999, and 2001. Based on their self-reported mental symptoms, a total of 116 men were selected for clinical examination in 2005. Half of them had high and the others low levels of adverse mental symptoms in all three previous follow-ups. A structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders-IV was performed. Depressive symptoms were assessed with the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). The Aging Males’ Symptoms scale was also compiled and testosterone levels were determined.ResultsIn the entire study sample, serum free testosterone levels correlated negatively with both BDI and HDRS scores. In the hypogonadism group (based on free testosterone, 19.8% of the sample), clinically significant depression (BDI score ≥ 13) was more than three times as frequent as in the other men (34.8% vs. 10.4%), the odds ratio after multiple adjustments being 4.98 (95% confidence interval 1.66–14.95). A decrease in sexual desire was common in hypogonadism (36%). Nevertheless, it also associated with clinically significant depression, irrespective of free testosterone levels.DiscussionLong-term and current depressive symptoms, a decreased sexual desire, and low serum free testosterone levels are associated in middle-aged men. Hypogonadism per se and as a cause of decreased sexual desire may be a contributory and possibly treatable factor underlying male depression.ConclusionsThe findings highlight the need for hormonal status assessment in middle-aged depressive men. Hintikka J, Niskanen L, Koivumaa-Honkanen H, Tolmunen T, Honkalampi K, Lehto SM, and Viinamäki H. Hypogonadism, decreased sexual desire, and long-term depression in middle-aged men. J Sex Med 2009;6:2049–2057. 相似文献
90.
Fixation of syndesmotic ruptures in 38 patients with a malleolar fracture: a randomized study comparing a metallic and a bioabsorbable screw 总被引:4,自引:0,他引:4
OBJECTIVES: To compare the performance of a metallic and a biodegradable screw in the fixation of tibia-fibula syndesmotic ruptures. DESIGN: A randomized, prospective, and blinded study. SETTING: Central hospital, Department of Surgery. PATIENTS: Forty consecutive patients with a clinically verified syndesmotic rupture in association with a malleolar fracture, of whom 38 completed the study. INTERVENTION: After syndesmosis rupture was diagnosed, implant selection was performed intraoperatively by a strict randomization with sealed envelopes. Eighteen patients were treated with a metallic screw, and 20 with a bioabsorbable polylevolactic acid screw. The metallic screws were removed in a second operation at 8 weeks postoperatively. All patients had a treatment-blinded clinical and radiographic control after a mean follow-up of 35 (range 17-51) months. MAIN OUTCOME MEASURES: Return to previous physical activity level, evaluation of ankle stability, range of motion, circumference of the ankle, and a radiographic evaluation of both ankles including a measure of the talocrural, medial joint, and syndesmotic space widths. RESULTS: More patients with a polylevolactic acid screw returned to their previous activity level, and there was less swelling in the ankles of these patients, but joint motion was similar between the groups. The mean values of syndesmotic and medial joint spaces were significantly higher in the radiographs of the operated ankles when compared to the uninjured ankle, but there was not a correlation to the type of screw used. CONCLUSIONS: Polylevolactic acid screws worked as well, or slightly better than, metallic ones in syndesmosis fixation in patients with an ankle fracture. 相似文献