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1.
Irina Elovaara Ilkka Seppl Esko Kinnunen Hannu Laaksovirta 《Journal of neuroimmunology》1991,35(1-3):65-77
The presence of free immunoglobulin light chains (FLCs) in the cerebrospinal fluid (CSF) and sera of patients with human immunodeficiency virus-1 (HIV-1) infection, multiple sclerosis (MS), and neurologically healthy control individuals was investigated by paying special attention to ensure that only truly free light chains would be detected. The FLCs were extracted by specifically binding them to Sepharose-coupled anti-FLC monoclonal antibodies, and thereafter they were electrophoresed and immunoblotted with monoclonal antibodies to both light chain (LC) isotypes. A frequent occurrence of kappa and lambda FLCs was found in both CSF and sera of HIV-1 infected patients. In HIV-1 infection and in MS, the frequency of FLCs of the CSF was equal. In healthy controls, only occasional weak FLCs were observed in either CSF or serum. FLC bands of the CSF from patients with HIV-1 infection tended to be more intensive than those of the appropriately diluted sera. Both intrathecal synthesis of FLCs and their transudation from sera through the impaired blood-brain barrier (BBB) may contribute to this. Increasing severity of general HIV-1 infection was accompanied by an increase of FLC intensity in sera. A qualitative demonstration of FLC in the CSF may be meaningful only in the absence of altered BBB function. 相似文献
2.
Why is the age-standardized incidence of low-trauma fractures rising in many elderly populations? 总被引:4,自引:0,他引:4
Pekka Kannus Seppo Niemi Jari Parkkari Mika Palvanen Ari Heinonen Harri Siev?nen Teppo J?rvinen Karim Khan Markku J?rvinen 《Journal of bone and mineral research》2002,17(8):1363-1367
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones. 相似文献
3.
The present study investigated relationships between global QOL perceptions and well-being dimensions. Especially our goal was to evaluate the impact of generally recognised four broad dimensions of QOL (physical, functional, social and emotional well-being) on global QOL perceptions, additionally person's satisfaction with life achievements and economical situation were measured as well as social demographic variables. The subjects were a representative sample of Finns (n = 4613, from 25 to 65 years) of the FINRISK-97 study. Correlation coefficients and models of hierarchical regression indicated that physical, functional and social well-being as well as sociodemographic factors and satisfaction with life achievements are important factors of global QOL perceptions both among males and females. However percentages of variances explained with these measures were only moderately high, ranging from 1 to 10%. After measures of emotional well-being were entered into the models of hierarchical analyses of regression, variances explained grew dramatically over 20%. The results of the study indicated that global QOL judgements are likely to be based on current emotional state. 相似文献
4.
Jere Paavola Matti Viitasalo P?ivi J Laitinen-Forsblom Michael Pasternack Heikki Swan Ilkka Tikkanen Lauri Toivonen Kimmo Kontula Mika Laine 《European heart journal》2007,28(9):1135-1142
AIMS: Mutations in cardiac ryanodine receptors (RyR2s) are linked to catecholaminergic polymorphic ventricular tachycardia (CPVT), characterized by risk of polymorphic ventricular tachyarrhythmias and sudden death during exercise. Arrhythmias are caused by gain-of-function defects in RyR2, but cellular arrhythmogenesis remains elusive. METHODS AND RESULTS: We recorded endocardial monophasic action potentials (MAPs) at right ventricular septum in 15 CPVT patients with a RyR2 mutation (P2,328S, Q4,201R, and V4,653F) and in 12 control subjects both at baseline and during epinephrine infusion (0.05 microg/kg/min). At baseline 3 and during epinephrine infusion, four CPVT patients, but none of the control subjects, showed delayed afterdepolarizations (DADs) occasionally coinciding with ventricular premature complexes. In order to study the underlying mechanisms, we expressed two types of mutant RyR2 (P2,328S and V4,653F) causing CPVT as well as wild-type RyR2 in HEK 293 cells. Confocal microscopy of Fluo-3 loaded cells transfected with any of the three RyR2s showed no spontaneous subcellular Ca(2+) release events at baseline. Membrane permeable cAMP analogue (Dioctanoyl-cAMP) triggered subcellular Ca(2+) release events as Ca(2+) sparks and waves. Cells expressing mutant RyR2s showed spontaneous Ca(2+) release events at lower concentrations of cAMP than cells transfected with wild-type RyR2. CONCLUSION: CPVT patients show DADs coinciding with premature action potentials in MAP recordings. Expression studies suggest that DADs are caused by increased propensity of abnormal RyR2s to generate spontaneous Ca(2+) waves in response to cAMP stimulation. Increased sensitivity of mutant RyR2s to cAMP may explain the occurrence of arrhythmias during exercise or emotional stress in CPVT. 相似文献
5.
Spontaneous abortions and congenital malformations among women exposed to tetrachloroethylene in dry cleaning. 总被引:2,自引:1,他引:1
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P Kyyr?nen H Taskinen M L Lindbohm K Hemminki O P Heinonen 《Journal of epidemiology and community health》1989,43(4):346-351
STUDY OBJECTIVE: The aim of the study was to determine whether exposure to tetrachloroethylene during the first trimester of pregnancy has harmful effects on pregnancy outcome. DESIGN: The study used record linkage identification of cases and case-control comparison. SETTING: The study involved dry cleaner and laundry workers throughout Finland who had become pregnant during the study period. Controls were age matched but otherwise unselected women giving birth to normal babies in the study period. SUBJECTS: Cases were defined as women who had been treated for spontaneous abortion or had delivered a malformed child. Out of 5700 workers nearly half had been pregnant during the study period. One pregnancy only was randomly selected for study per worker, and the final study population was 247 women with spontaneous abortions and 33 with malformed infants. Three age matched controls were selected for each abortion case and five for each malformation case. MEASUREMENTS AND MAIN RESULTS: Three women out of four had worked in early pregnancy. Exposure information was collected from 1108 women by mailed questionnaires, with a 77% response, and was partly confirmed by biological monitoring data. Exposure to tetrachloroethylene was found to be significantly associated with spontaneous abortions (odds ratio 3.6, p less than 0.05). CONCLUSION: The findings, together with other available data, indicate that exposure of pregnant women to tetrachloroethylene needs to be minimised. 相似文献
6.
Juhani Trmnen Osmo Tervonen Antero Koivula Juhani Junila Ilkka Suramo 《Journal of magnetic resonance imaging : JMRI》1996,6(5):805-811
The purpose of this study was to explore systematically the effect of the imaging parameters changeable by the user in spin-echo (SE) imaging sequences to minimize image distortion when imaging joint prostheses. A titanium alloy hip joint prosthesis was studied at 1.0 T. The SE imaging parameters were bandwidth/pixel (BW/p), TE, strength of encoding gradients (matrix size), echo train length (ETL), and direction of phase and frequency encoding. The effect of ETL in rapid acquisition relaxation enhanced (RARE) sequences was also evaluated with a turbo-SE sequence using a different ETL with the same TR and an effective TE. It is concluded that an optimized image quality can be achieved in SE imaging by using a high bandwidth/pixel value (at least 130 Hz/pixel), a high resolution matrix (256–512), sequences with multiple refocusing, and a frequency-encoding axis parallel to the long axis of the prosthesis. The degree of distortion is reduced with this optimized technique. 相似文献
7.
Simultaneous transcutaneous PO2 (PtcO2) recordings, done on a neonate having preductal coarctation of the aorta, showed markedly lower PtcO2 values in the lower abdominal quadrant (representing postductal blood) than in the subclavicular area (representing preductal blood). Two-sensor PtcO2 recordings are valuable in documenting pathologic ductal shunts commonly associated with disturbed transitional circulation or cardiac malformation in newborn infants. 相似文献
8.
Ilkka Sinisaari Hannu Pätiälä Ole Böstman E. Antero Mäkelä Esa K. Partio Eero Hirvensalo Pertti Törmälä Pentti Rokkanen 《Journal of orthopaedic science》1997,2(2):88-92
Between November 1984 and January 1994 in our department, a total of 2500 patients were treated with totally absorbable internal
fixation devices. We studied these patients and analyzed results with regard to the volume of the absorbable implants and
the development of wound infection. Of the 2500 patients 2044 were trauma patients and 456 were operated on for orthopedic
disease. In 1466 patients treated with implants made of self-reinforced polyglycolic acid (SR-PGA) only, the patients who
developed wound infection had a higher implant volume (P=0.07) than those who did not; this difference was close to statistical significance. In the 446 patients who received only
implants made of self-reinforced poly-l-lactic acid (SR-PLLA), the 5 who developed wound infection had a mean implant volume more than three times that of the non-infected
patients (P=0.01). We found that in the patients treated with the earlier SR-PGA implants, which contained a green staining material,
there was no correlation between implant volume and incidence of wound infections. On the other hand, both the non-stained
SR-PGA implants, which have been in clinical use since 1989, and the SR-PLLA implants, seem to be more predictable in terms
of wound infections. We believe that this difference, is largely due to the lower level of tissue reactions with these newer
implants. 相似文献
9.
C. Blomqvist K. Tiusanen I. Elomaa P. Rissanen T. Hietanen E. Heinonen P. Gr?hn 《British journal of cancer》1992,66(6):1171-1176
Two hundred patients with node positive stage II breast cancer were randomised to four groups after radical mastectomy and axillary evacuation: (1) Postoperative radiotherapy, (2) Adjuvant chemotherapy with eight courses of CAFt (cyclophosphamide 500 mg m-2 + doxorubicin 40 mg/m-2 + ftorafur 20 mg kg-1 orally day 1-14) every fourth week, (3) Postoperative radiotherapy and adjuvant chemotherapy and (4) postoperative radiation, adjuvant chemotherapy and tamoxifen 40 mg daily for 2 years. Thirty-two per cent of the patients discontinued treatment due to GI-toxicity, while 26% required dose reductions due to leukopenia. Radiation pneumonitis was more frequent after the combination of postoperative radiotherapy with chemotherapy. There was a better relapse-free survival in the groups receiving chemotherapy compared to radiotherapy alone (P = 0.05), which was highly significant in a multivariate Cox analysis (P = 0.004). No significant survival differences were seen. Tamoxifen had no clear overall effect but there were better relapse-free (P = 0.04) and overall (P = 0.004) survival with tamoxifen in estrogen receptor positive patients, while estrogen receptor negative patients had a somewhat poorer survival (P = 0.07) after tamoxifen. Local control was better (NS) after the combination (93%) radiotherapy and chemotherapy compared to either treatment alone (76% with radiotherapy and 74% with chemotherapy at 5 years). 相似文献
10.
Tim Söderlund Ilkka Tulikoura Mika Niemelä Lauri Handolin 《European journal of trauma and emergency surgery》2009,35(5):455-462