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131.
Lauri Raitamaa Niko Huotari Vesa Korhonen Heta Helakari Anssi Koivula Janne Kananen Vesa Kiviniemi 《Human brain mapping》2021,42(13):4298
Physiological pulsations have been shown to affect the global blood oxygen level dependent (BOLD) signal in human brain. While these pulsations have previously been regarded as noise, recent studies show their potential as biomarkers of brain pathology. We used the extended 5 Hz spectral range of magnetic resonance encephalography (MREG) data to investigate spatial and frequency distributions of physiological BOLD signal sources. Amplitude spectra of the global image signals revealed cardiorespiratory envelope modulation (CREM) peaks, in addition to the previously known very low frequency (VLF) and cardiorespiratory pulsations. We then proceeded to extend the amplitude of low frequency fluctuations (ALFF) method to each of these pulsations. The respiratory pulsations were spatially dominating over most brain structures. The VLF pulsations overcame the respiratory pulsations in frontal and parietal gray matter, whereas cardiac and CREM pulsations had this effect in central cerebrospinal fluid (CSF) spaces and major blood vessels. A quasi‐periodic pattern (QPP) analysis showed that the CREM pulsations propagated as waves, with a spatiotemporal pattern differing from that of respiratory pulsations, indicating them to be distinct intracranial physiological phenomenon. In conclusion, the respiration has a dominant effect on the global BOLD signal and directly modulates cardiovascular brain pulsations. 相似文献
132.
Järvenpää J Oikarinen L Korhonen P Väänänen H Toivonen L Viitasalo M 《The American journal of cardiology》2007,99(3):295-299
Prolonged and labile ventricular repolarization and decreased heart rate variability may be associated with susceptibility to ventricular fibrillation (VF) after myocardial infarction (MI). The response of ventricular repolarization related to abrupt heart rate changes may also be associated with arrhythmia vulnerability. We investigated whether diurnal maximal values or changing capacities of QT and T-wave peak to T-wave end (TPE) intervals are different in patients after MI with and without a history of VF. With an automated computerized program, Holter recordings from 29 patients after MI resuscitated from VF not associated with new MI (VF group) and 27 patients after MI without clinical ventricular arrhythmias (control group) were analyzed. Maximal QT and maximal TPE intervals were shorter in the VF group than in the control group. Patients with VF exhibited smaller capacity to change QT and TPE intervals, with differences between study groups being greatest at heart rates from 60 to 75 beats/min (p = 0.002 and 0.01, respectively). Capacity to change QT and TPE intervals correlated with vagally mediated measurements of heart rate variability (r from 0.35 to 0.46, p from 0.01 to <0.001, respectively). In conclusion, long maximal QT interval may not be the key factor exposing patients after MI to VF. Impaired capacity to change QT and TPE intervals seems to be associated with risk of VF after MI. 相似文献
133.
Linder LA 《Journal of pediatric nursing》2008,23(4):296-309
The purpose of this literature review was to evaluate developmental diversity in studies describing physical symptoms in children and adolescents receiving cancer treatment. Developmental diversity was conceptualized as individual differences based on normal stages of human development, including cognitive, psychosocial, and physiologic aspects. Searches of Medline and the Cumulative Index of Nursing and Allied Health Literature identified 53 articles published between January 1986 and November 2006. Most studies addressed symptoms in school-aged children and adolescents; few compared symptoms across age groups. Additional measures are needed to describe younger children's symptoms. Alternate research methodologies may be appropriate to describe their symptom experiences. 相似文献
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135.
Objective. The majority of patients with coeliac disease remain undetected world-wide. Finland has aimed at a high detection rate by training health personnel, and has advocated serologic screening for known coeliac disease risk groups. The purpose here was to assess whether this approach has been effective in clinical practice. Material and methods. The study was based on a prospective database of new coeliac patients aged 16 years or more, to whom the Social Insurance Institution had paid monthly compensation for the additional cost of maintaining a gluten-free diet since 2002. To obtain this compensation the diagnostic criteria for coeliac disease, including biopsy findings, had to be attested in a statement from a physician. The incidence and prevalence rates were calculated until the end of 2006. The total population aged 16 years or more was 4.31 million. Results. In 2004–06, a total of 5020 persons (64% female) receiving a new dietary grant were identified through the database. The mean annual incidence of proven coeliac disease was thus 39 per 100,000 individuals. Altogether, 23,553 persons received the dietary grant. This gives a nation-wide point prevalence of adult coeliac disease of 0.55% (0.70% F, 0.38% M). There was a regional variation from 33 to 49 per 100,000 in the annual incidence and from 0.41% to 0.72% in the prevalence of coeliac disease. Conclusions. To the best of our knowledge, these figures for proven coeliac disease are the highest reported. Increased alertness to the condition and active case finding has made this efficient diagnostics possible. 相似文献
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138.
Irja Vent? Ani Lakoma Sauli Haahtela Jaakko Peltola Pekka Ylipaavalniemi Lauri Turtola 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,99(5):546-549
OBJECTIVE: The aim of the study was to examine oral piercings among first-year university students. STUDY DESIGN: First-year university students in 2002 were invited to a dental examination (n = 234; 49 men and 185 women). Students with piercings formed the study group and the rest served as controls. The methods included decayed, missing, and filled teeth (DMF) index, stimulated salivary flow rates, panoramic tomograms, and questionnaires including the Depression Inventory of Beck. Fisher's 2-sided exact test was used for statistical analysis. RESULTS: The prevalence of oral piercings was 3.4%. In the DMF indices, no statistically significant differences existed between the groups. Increased salivary flow rates were noted among students with piercings (63% vs 26%, P < .05). Use of tobacco and illicit drugs, and also depression, were more prevalent in the study group than in the controls. CONCLUSION: Because of the possibility of oral implications, follow-up of oral piercings is essential. 相似文献
139.
A new triphenylethylene compound,Fc-1157a 总被引:4,自引:0,他引:4
Lauri Kangas Anna-Liisa Nieminen Guillermo Blanco Matti Grönroos Sinikka Kallio Arto Karjalainen Milla Perilä Marja Södervall Reijo Toivola 《Cancer chemotherapy and pharmacology》1986,17(2):109-113
Summary The antitumor effects of a new antiestrogen, Fc-1157a1 have been studied in vitro and in vivo. In vitro the effect of Fc-1157a was comparable to that of tamoxifen. The effect was dose-dependent, and at concentrations higher than 10-6 mol/l Fc-1157a induced real cell death of the MCF-7 cells. In DMBA-induced mammary cancer in rats Fc-1157a decreased the number of new tumors and inhibited the growth of existing tumors, these effects being statistically highly significant. The ratio of growing tumors to stable and regressing tumors was significantly decreased. Although these effects were slightly stronger with Fc-1157a than with tamoxifen, the difference between these two compounds was not statistically significant.Murine uterine sarcoma, an estrogen receptor-negative tumor, was resistant to tamoxifen, but was statistically significantly inhibited by high doses (100 and 200 mg/kg-1 day-1 for 5 days) of Fc-1157a.The antitumor effects of Fc-1157a are due mainly to the antiestrogenic activity. At high concentrations in vitro and at high doses in vivo Fc-1157a exerts antitumor effects some of which are different from those of tamoxifen and are directed even against estrogen receptor-negative tumors. The exact mechanism of the observed cytolytic effect at high doses is unknown. 相似文献
140.
Irja Vent? Pekka Ylipaavalniemi Lauri Turtola 《Journal of oral and maxillofacial surgery》2004,62(2):182-185
PURPOSE: The aim of the present study was to follow the clinical changes in third molar status during an 18-year period in patients aged 20 to 38 years. PATIENTS AND METHODS: The series consisted of 118 subjects (37 men and 81 women). In the beginning of the study, the mean age was 20.2 years (SD, +/-0.6 year), and at the end, it was 38.6 years (SD, +/-0.6 year). Panoramic radiographs were taken at baseline and at age 38. All of the subjects were clinically examined at baseline and at the end of the study. A portion of the subjects (n = 69) were also examined at age 32. RESULTS: Most of the initially unerupted third molars were removed during the follow-up period (73%, maxilla and mandible together). More than half of the initially partially erupted third molars were removed during the follow-up period (64%, maxilla and mandible together). The percentage of erupted third molars found in the mouth at age 38 increased significantly depending on the initial status. Of the initially unerupted, partially erupted, or erupted third molars, 10%, 33%, and 50%, respectively, were erupted at age 38 (maxilla and mandible together). Changes in the status of third molars continued from age 32 to age 38, although to a lesser extent (8%). The 3 third molars with advanced eruption were all maxillary teeth in men. CONCLUSION: Third molars undergo continuous clinical change on a reduced scale at least up to the age of 38 years. 相似文献