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991.
BACKGROUND: The maintenance of health registers has become routine. The main prerequisite for their use is that registers be complete and that their contents correspond to reality. METHODS: Data on all primiparous women who gave birth between 1987 and 1989 (N=73009) and on their second (N=55388) and third births (N=22904) in the 1987-1998 period were retrieved from the Finnish Medical Birth Register (MBR). The consistency of the MBR data on reproductive history and on previous Caesarean section was investigated by comparing the records on subsequent births. MAIN RESULTS: In total 98.5% of the information on reproductive history corresponded with the previous data in the MBR. Data quality decreased over time and with increasing parity. There were problems with the registration of rare cases, e.g. several extrauterine pregnancies or stillbirths. The quality deteriorated in the late 1990s, because no data on previous induced abortions and extrauterine pregnancies were collected between 1991 and 1995. The quality of data on previous Caesarean section was poor in 1987-1990, a period when the data were collected by using ICD-9 codes, but the quality improved after the introduction of a check-box format in 1991. CONCLUSIONS: Changes in question formats may change the quality of register data significantly. Check-boxes seem to improve quality compared to open-ended questions. The data on reproductive history and previous Caesarean sections could be combined routinely to improve the quality of the MBR.  相似文献   
992.
Safety and efficacy of this new treatment modality for out-patients were evaluated by an uncontrolled multicenter trial under GCP-conditions. Patients had to undergo 3-5 treatment sessions per week up to 35 in total. SCORAD (SC) was assessed at baseline, after 20 and 35 sessions. For patients with early study withdrawal the last-observation-carry-forward-principle was used. 615 intention-to-treat (itt)- (baseline SC: 59.4) and 143 according-to-protocol (atp)-patients (baseline SC: 60.1) could be analysed. 289 patients (47%) (baseline SC: 59.1) underwent less than 35 sessions. Main reasons were: lack of time (16%), non-compliance (12%), good improvement (7%), lack of efficacy (6%), intercurrent disease (4%) and side effects (3%). Mean number of sessions in atp-group was 35, in itt 26, and in patients with early study withdrawal 15.8. SC decreased in atp-group to 37.5 (itt: 44.5/patients with early study withdrawal: 46.1) after 20 sessions and to 27.1 (35.2/42.6) at end of treatment. Relative SC-improvement was statistically significant in atp- (55%), itt-group (41%), and in patients with early study withdrawal (26%). Most frequent side effects were: erythema in 7.3%, burning of skin due to salt solution in 3.6%. Safety and efficacy could be proven in both atp- and itt-group. A marked difference in efficacy between atp and itt underlines the importance of evaluating itt-data providing a more realistic assessment of a treatment modality in practice. This treatment is especially recommended for patients with chronic type of AD, high compliance and time free for therapy.  相似文献   
993.
Replacement of iron with cobalt(III) selectively introduces a deep trap in the folding-energy landscape of the heme protein cytochrome c. Remarkably, neither the protein structure nor the folding thermodynamics is perturbed by this metal-ion substitution, as shown by data from spectroscopic and x-ray diffraction experiments. Through kinetics measurements, we have found parallel folding pathways involving several different misligated Co(III) species, and, as these folding intermediates persist for several hours under certain conditions, we have been able to elucidate fully their spectroscopic properties. The results, along with an analysis of the fluorescence energy-transfer kinetics during refolding, show that rapidly equilibrating populations of compact and extended polypeptide conformations are present until all molecules have reached the native structure. These measurements provide direct evidence that collapsed denatured structures are not substantially more stable than extended conformations of cytochrome c.  相似文献   
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995.
Low-molecular-weight heparin (LMWH) inhibits the activity of the intrinsic factor X activation complex, a property that persists when LMWH is rendered low affinity (LA) for antithrombin, but is reduced when it is N-desulfated. When LA-LMWH is hypersulfated (sLA-LMWH), its potency against intrinsic tenase is increased and it acquires inhibitory activity against prothrombinase. sLA-LMWH functions by interfering with the association of enzyme and cofactor in both activation complexes. In a rabbit carotid artery thrombosis prevention model, sLA-LMWH is superior to LMWH. Because of its low affinity for antithrombin and multiple sites of action, sLA-LMWH may prove to be safer and more effective than other anticoagulants.  相似文献   
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Schoels W  Bauer A  Becker R  Senges JC  Voss F 《Herz》2002,27(4):306-311
BACKGROUND: Although several classical studies seemed to provide clear ideas on the pathophysiology of atrial fibrillation, current concepts have to be modified on the basis of more recent findings. REENTRANT CIRCUITS: Based on the findings of Garrey and of Moe & Abildskov, atrial fibrillation has long been considered as the prototype of an arrhythmia being caused by multiple, random reentrant circuits, the number of which would determine the stability of the reentrant process. Local refractory and conduction properties would determine the size of individual circuits, a hypothesis quite convincing with respect to refractoriness, but so far hard to prove with respect to conduction. The finding that rapid atrial rates shorten atrial refractory periods and reverse rate adaptation (atrial remodeling) has coined the phrase "atrial fibrillation begets atrial fibrillation", indicating that any atrial tachyarrhythmia modifies the substrate in a way that favors reentry. With intracellular calcium overload being the initial trigger, down-regulation of genes encoding for calcium channels seems to primarily account for atrial remodeling. Primarily neglected concepts on the pathophysiology of atrial fibrillation suggesting single, meandering circuits or focal activity have regained attention. Atrial fibrillation as a random phenomenon is questioned not only by the dominant role of the left atrium for the maintenance of the arrhythmia, but also by most recent data demonstrating a spatio-temporal periodicity in activation patterns. Finally, ablation studies have provided convincing evidence that there is a subset of patients with focal or at least focally induced atrial fibrillation.  相似文献   
1000.
BACKGROUND: Immunoglobulin-A in saliva (SIgA) has been proven to be decreased during periods of stress, a change that also correlates with increased disease risk. HYPOTHESIS: Concentration of SIgA is negatively associated with dietary deprivation, negative moods, and anxiety. METHODS: SIgA was evaluated as a marker of the severity of stress during a 19-day Royal Australian Air Force (RAAF) survival course, during which students experienced hunger, thirst, boredom, loneliness, and extreme heat and cold combined with demanding physical effort. There were 27 men and 2 women who participated. Students kept daily food diaries, from which daily intakes of energy and macronutrients were calculated. Saliva samples were collected on 9 d for the measurement of the ratio of SIgA to albumin (Alb). Students completed a health checklist and the State Anxiety Inventory on the same 9 d and the Profile of Mood States on 3 of the days. RESULTS: Dietary restriction, consumption of alcohol, body mass loss, occurrence of upper respiratory tract infection, and negative emotions were negatively associated with SIgA:Alb. CONCLUSION: SIgA:Alb is a useful marker of the severity of stresses encountered during stressful training.  相似文献   
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