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41.
Pasi L?hteenm?ki G. S. Paraoanu Juha Hassel Pertti J. Hakonen 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(11):4234-4238
The zero-point energy stored in the modes of an electromagnetic cavity has experimentally detectable effects, giving rise to an attractive interaction between the opposite walls, the static Casimir effect. A dynamical version of this effect was predicted to occur when the vacuum energy is changed either by moving the walls of the cavity or by changing the index of refraction, resulting in the conversion of vacuum fluctuations into real photons. Here, we demonstrate the dynamical Casimir effect using a Josephson metamaterial embedded in a microwave cavity at 5.4 GHz. We modulate the effective length of the cavity by flux-biasing the metamaterial based on superconducting quantum interference devices (SQUIDs), which results in variation of a few percentage points in the speed of light. We extract the full 4 × 4 covariance matrix of the emitted microwave radiation, demonstrating that photons at frequencies symmetrical with respect to half of the modulation frequency are generated in pairs. At large detunings of the cavity from half of the modulation frequency, we find power spectra that clearly show the theoretically predicted hallmark of the Casimir effect: a bimodal, “sparrow-tail” structure. The observed substantial photon flux cannot be assigned to parametric amplification of thermal fluctuations; its creation is a direct consequence of the noncommutativity structure of quantum field theory. 相似文献
42.
Tuija H. Nieminen Nora M. Hagelberg Teijo I. Saari Mikko Neuvonen Kari Laine Pertti J. Neuvonen Klaus T. Olkkola 《European Journal of Pain》2010,14(8):854-859
Background: Chronic pain is associated with depression. Self‐treatment of depression with herbal over‐the‐counter medicine St John's wort makes pain patients prone to drug interactions. Aims: The aim of this study was to assess the potential of St John's wort to alter the CYP3A‐mediated metabolism of a μ‐opioid receptor agonist, oxycodone. Methods: The study design was placebo‐controlled, randomized, cross‐over with two phases at intervals of 4 weeks and was conducted with 12 healthy participants. St John's wort (Jarsin®) or placebo was administered t.i.d. for 15 days and oral oxycodone hydrochloride 15 mg on day 14. Oxycodone pharmacokinetics and pharmacodynamics were compared after St John's wort or placebo. Behavioural and analgesic effects were assessed with subjective visual analogue scales and cold pressor test. Plasma drug concentrations were measured from 0 to 48 h, behavioural and analgesic effects from 0 to 12 h. Results: Following St John's wort administration the oxycodone AUC decreased 50% (p < 0.001). Oxycodone elimination half‐life shortened from a mean ± SD 3.8 ± 0.7 to 3.0 ± 0.4 h (p < 0.001). The self‐reported drug effect of oxycodone as measured by AUEC0–12 decreased significantly (p = 0.004). Differences between St John's wort and placebo phases in cold pain threshold and intensity AUEC0–12 were not observed. Conclusions: St John's wort greatly reduced the plasma concentrations of oral oxycodone. The self‐reported drug effect of oxycodone decreased significantly. This interaction may potentially be of some clinical significance when treating patients with chronic pain. 相似文献
43.
This paper traces the role of alcohol production and use in the daily lives of people in India, from ancient times to the present day. Alcohol use has been an issue of great ambivalence throughout the rich and long history of the Indian subcontinent. The behaviors and attitudes about alcohol use in India are very complex, contradictory and convoluted because of the many different influences in that history. The evolution of alcohol use patterns in India can be divided into four broad historical periods (time of written records), beginning with the Vedic era (ca. 1500–700 BCE). From 700 BCE to 1100 CE, (“Reinterpretation and Synthesis”) is the time of emergence of Buddhism and Jainism, with some new anti-alcohol doctrines, as well as post-Vedic developments in the Hindu traditions and scholarly writing. The writings of the renowned medical practitioners, Charaka and Susruta, added new lines of thought, including arguments for “moderate alcohol use.” The Period of Islamic Influence (1100–1800 CE), including the Mughal era from the 1520s to 1800, exhibited a complex interplay of widespread alcohol use, competing with the clear Quranic opposition to alcohol consumption. The fourth period (1800 to the present) includes the deep influence of British colonial rule and the recent half century of Indian independence, beginning in 1947. The contradictions and ambiguities—with widespread alcohol use in some sectors of society, including the high status caste of warriors/rulers (Kshatriyas), versus prohibitions and condemnation of alcohol use, especially for the Brahmin (scholar-priest) caste, have produced alcohol use patterns that include frequent high-risk, heavy and hazardous drinking. The recent increases in alcohol consumption in many sectors of the general Indian population, coupled with the strong evidence of the role of alcohol in the spread of HIV/STI infections and other health risks, point to the need for detailed understanding of the complex cross-currents emerging from the past history of alcohol use and abuse in India. 相似文献
44.
Katja Marnela MD Sami Saarelainen MD Outi Palomäki MD PhD Pertti Kirkinen 《Journal of clinical ultrasound : JCU》2010,38(4):205-208
Two cases of post‐partum uterine artery pseudoaneurysm are described, 1 after normal vaginal delivery and the other after Caesarean section. Both cases were complicated by heavy bleeding and treated with catheter embolization. A turbulent arterial‐type velocity waveform with high peak velocity and forward end‐diastolic flow was registered in the feeding vessel. The peak blood flow velocity was high in both cases. The resistance index in the uterine artery was lower in the affected side of the uterus. Three‐dimensional angiosonography was used to calculate the volume of the lesion, demonstrate its shape, and identify the feeding vessel. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 相似文献
45.
Yrj U. Collan Matti J. Eskelinen Stig A. Nordling Pertti Lipponen Erkki Pesonen Leena M. Kumpusalo Pfkka Pajarinen Kauko O. Kettunen 《Acta oncologica (Stockholm, Sweden)》1994,33(8):873-878
We studied histological samples and clinical data from 111 breast carcinoma patients originally treated in 1975-1977 who did not have distant metastases at the time of diagnosis. A multivariate survival analysis using the Cox model selected the studied variables in the following order according to their prognostic association (breast cancer deaths, or deaths from any cause): axillary lymph node status, tumor size, mitotic index, and DNA ploidy status. The association of the different variables to the prognosis in respect to breast cancer deaths was evaluated 1-10 years after treatment by stepwise logistic regression. Lymph node status, tumor size, mitotic index, and DNA ploidy all showed significant relation to the prognosis but this association varied considerably with time of observation. 相似文献
46.
Satu L. B. Vesalainen Pertti K. Lipponen Martti T. Talja Esko M. Alhava Kari J. Syrjnen 《International journal of cancer. Journal international du cancer》1994,58(2):303-308
The expression of proliferating cell nuclear antigen and p53 protein was analysed by immunocytochemical methods (PC10, CMI antisera) in 139 patients with T1-2MO prostatic adenocarcinomas followed-up for > 12 years. p53 protein was expressed in 21 (15%) tumours (15%), the fraction of positive nuclei being very low (mean SE, 1% ± 0.7%). Accumulation of p53 protein in epithelial cells was independent of tumour stage and Gleason score, and had no effect on prognosis. In 4 cases, p53 protein was expressed only in stromal cells. The fraction of PCNA-positive nuclei (evaluable in 116 cases) was higher in T2 than in T1 tumours (p < 0.001); furthermore, high Gleason score was positively correlated with PCNA positivity (p < 0.001). A finding of over 5% of PCNA-positive nuclei predicted progression in T and M categories and were a sign of poor outcome. The fraction of PCNA-positive stromal-cell nuclei was related to T-category with a borderline significance (p = 0.06). In a multi-variate analysis of the prognostic factors, independent predictors of survival included Gleason score (p < 0.001), fraction of PCNA-positive nuclei (p = 0.013), observation before therapy (p = 0.05), and T-category (p = 0.07) in that order of significance. The results suggest that overexpression of p53 protein is of marginal prognostic value in local prostatic adenocarcinomas, whereas direct measurement of cell proliferation by PCNA immunolabelling provides important prognostic information in T1-2MO tumours, in addition to the Gleason score. 相似文献
47.
Factors explaining recurrence in patients undergoing chemoimmunotherapy regimens for frequently recurring superficial bladder carcinoma 总被引:4,自引:0,他引:4
Kaasinen E Rintala E Hellström P Viitanen J Juusela H Rajala P Korhonen H Liukkonen T;FinnBladder Group 《European urology》2002,42(2):167-174
OBJECTIVES: To study the factors determining new recurrences in patients with frequently recurring superficial bladder tumors. METHODS: Of all 205 eligible patients, each received 5 weekly intravesical instillations of mitomycin C (MMC), with the first instillation given perioperatively. This was followed, according to randomization, by BCG instillations alone or by alternating instillations of interferon-alpha and BCG monthly for up to 1 year. Impact of 12 variables on time to first recurrence was retrospectively studied with the Cox multiple hazards regression and Kaplan-Meier analysis. RESULTS: Type of regimen was the most significant factor determining new recurrences, with preceding recurrence rate being the most important prognostic factor. Timing of the first MMC was the third significant predictor in the main multivariate analysis, with more than a two-fold relative risk for a new recurrence if the first MMC instillation was given later than on day 0. CONCLUSION: Preceding recurrence rate, most accurately reflects, in patients with frequently recurring tumors, the inherent risk for new recurrences. This risk can be considerably reduced by use of an effective chemoimmunotherapy regimen, and in addition, by inclusion of an early perioperative chemotherapy instillation in such a regimen. 相似文献
48.
Varho TT Alajoki LE Posti KM Korhonen TT Renlund MG Nyman SR Sillanpää ML Aula PP 《Pediatric neurology》2002,26(4):267-273
Salla disease (MIM 269920) represents the mildest phenotype among recessively inherited lysosomal-free sialic acid storage disorders. Although the vast majority of Salla disease patients in Finland share the same founder mutation, R39C in the SLC17A5 gene, there still is a wide clinical variation among mentally retarded, ataxic patients. We evaluated neurologic and neurocognitive findings of Salla disease in a cross-sectional study of 41 Finnish patients who were 11 months to 63 years of age (median = 19.5 years). The phenotype of Salla disease could be classified into two main categories. The majority of patients (90%) had so-called conventional phenotype, including a subgroup of seven patients with relatively mild symptoms. All but two patients with conventional phenotype were homozygous for the Finnish founder mutation. Four severely disabled, profoundly mentally retarded patients, 15-28 years of age, clearly could be clinically delineated as a separate group, likely reflecting the underlying compound heterozygous genotype. A typical developmental pattern could be outlined in the conventional type of the disease, emphasizing a strong motor handicap in Salla disease. The cognitive profile consisted of better verbal ability, especially speech comprehension, compared with nonverbal functioning in all patients. Our results indicate a partial genotype-phenotype correlation, although factors other than the molecular background are also involved in the phenotypic manifestation of Salla disease. 相似文献
49.
50.
Jansson KA Karjalainen PT Harilainen A Sandelin J Soila K Tallroth K Aronen HJ 《Skeletal radiology》2001,30(1):8-14
Objective. Several MRI sequences were used to evaluate the 2-year postoperative appearance of asymptomatic knee with a torn anterior
cruciate ligament (ACL) reconstructed with bone–patellar tendon–bone (BTB) and semitendinosus and gracilis (STG) tendon autografts.
Design and patients. Two groups with successful repair of ACL tear with BTB (n=10) or STG (n=10) autografts were imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-weighted and sagittal STIR sequences
and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligamentous tissues
was evaluated.
Results. In all 20 cases, the ACL graft showed homogeneous, low signal intensity with periligamentous streaks of intermediate signal
intensity on T2-weighted images. In 10 cases, localised areas of intermediate signal intensity were seen in the intra-articular
segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in either of the
two groups, but mild to moderate periligamentous enhancement was detected in 10 cases.
Conclusion. The MRI appearance of ACL autograft is variable on proton density- and T1-weighted images. Periligamentous tissue showing
contrast enhancement is a typical MRI finding after clinically successful ACL reconstruction.
Received: 22 February 2000 Revision requested: 27 June 2000 Revision received: 21 August 2000 Accepted: 23 August 2000 相似文献