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排序方式: 共有1932条查询结果,搜索用时 15 毫秒
101.
Surakka J Romberg A Ruutiainen J Virtanen A Aunola S Mäentaka K 《Clinical rehabilitation》2004,18(6):652-659
OBJECTIVE: To measure muscle strength and motor fatigue with a knee dynamometer and to assess the intra-rater reliability of measurements for maximal isometric extensor and flexor torques and the reliability of a new fatigue index (FI) in patients with mild to moderate multiple sclerosis (MS). DESIGN: Repeated assessments with one-week intervals. SETTING: The Masku Neurological Rehabilitation Centre, Masku, and the Social Insurance Institution, Research Department, Turku, Finland. SUBJECTS: Twenty-eight MS patients. OUTCOME MEASURES: Maximal isometric torque during 5 s and fatigue of knee flexors and extensors during isometric contractions of 30 s were assessed. A new FI was established and compared with the two previously used indices (FI1 and FI2). All three indices are based on the calculated area under the force versus time curve (AUFC), with FI1 using the 30-s recording time in its entirety and F2 omitting the initial 5 s in the calculation. In the new fatigue index (FI3), the time point of maximum (TPM) torque achieved by the subject is used as the starting point in the calculation. The patient's subjective fatigue was measured by Fatigue Severity Scale (FSS). RESULTS: The intraclass correlation coefficient (ICC) was 0.97 in maximal isometric torque measurements. FI3 showed good intra-rater reliability (ICC =0.68-0.86). None of the fatigue indices correlated with FSS. CONCLUSIONS: Maximal isometric torque and motor fatigue of knee flexor and extensor muscles can be reliably measured using a knee dynamometer in MS patients. The new FI proved to be a reliable model for MS patients. 相似文献
102.
Koivisto M Virjonen T Heikkilä T Lehto VP 《Journal of pharmaceutical and biomedical analysis》2004,36(3):559-564
The crystallographic texture, i.e. the preferred orientation of crystallites of delta-mannitol samples, has been experimentally determined by pole figure analysis. The pole figures were measured with an X-ray diffraction texture goniometer. It was found that already the uncompressed delta-mannitol powder sample was slightly texturized so that the (0 2 0) plane was parallel to the upper surface of the sample. The degree of preferred orientation was found to significantly increase when the powder was compressed to a tablet with the minimum (74MPa) compression pressure. Nevertheless, the direction of the texture remained parallel to the tablet surface. Maximum compression (740MPa) did not increase the degree of preferred orientation further. The compression time (0 or 60s) was not found to noticeably affect the strength or direction of the texture. The extent of the texture inside the tablet was determined with a tablet surface grinding experiment. The degree of preferred orientation was found to decrease under the surface while the orientation remained the same. The results were confirmed with orientation distribution function (ODF) calculations. 相似文献
103.
Paananen H Holopainen M Kalliokoski P Kangas J Kotilainen M Pennanen S Savolainen H Tossavainen A Luoto K 《Journal of occupational and environmental hygiene》2004,1(2):82-87
The objectives of this study were to develop a biomonitoring method for the assessment of exposure to man-made vitreous fibers (MMVF), to examine the level of exposure to MMVF in the prefabricated house industry, and to study nasal inflammatory reactions and respiratory symptoms associated with MMVF among workers. Nasal lavage was performed on workers from two factories, and concentrations of MMVF were measured by electron microscopy. Cytokines (IL-6, IL-8, TNF-alpha, and IFN-gamma) were also assayed and inflammatory cells (lymphocytes, eosinophils, neutrophils, and macrophages) were counted microscopically. Concentrations of airborne fibers (longer than 5 microm) were measured for comparison. Moreover, the exposure to MMVF and the related symptoms were studied with a structured questionnaire. In nasal lavage samples, the mean concentration of MMVF (length >1.5 microm) was 3260 f/ mL in Factory 1, 1680 f/mL in Factory 2, and below 500 f/mL in the control group. About 52% of the retained fibers were longer than 100 microm. The group-specific mean concentrations of MMVF in nasal lavage samples correlated with production rates and airborne fiber levels in both plants. The airborne concentrations of MMVF both in the breathing zone and fixed-point samples were low (below 0.1 f/cm(3)). No significant differences in the biological response (inflammatory cells, cytokines) were found between the groups exposed and the control group. The workers complained of some irritation of the skin, eyes, and upper respiratory tract, which could be reduced by appropriate protective equipment. It is concluded that nasal lavage can be used as a biomonitoring method in the assessment of MMVF exposure. 相似文献
104.
105.
Sinisalo M Aittoniemi J Koski T Tobin G Thunberg U Sundström C Rosenquist R Käyhty H Vilpo J 《Leukemia & lymphoma》2004,45(12):2451-2454
Chronic lymphocytic leukemia (CLL) is a clonal B-cell disorder, which has recently been divided into 2 subtypes based on the somatic hypermutation status of the immunoglobulin heavy chain (IgVH) genes. In patients with unmutated tumor cells the survival time is approximately half of that in mutated cases, but the reason for this difference is poorly understood. Since infections are the major cause of mortality in CLL, we investigated the effect of the mutation status on host immunity and proneness to infections in patients with CLL. As expected, the disease progression seemed to be faster and the disease more advanced (Binet B and C) among unmutated patients than in the mutated ones. Surprisingly, no differences in humoral immunity [immunoglobulin G (IgG), IgM, IgA, IgG subclasses, anti-ABO blood group antibodies and mannan-binding lectin (MBL)] or immune responses (Haemophilus influenzae serotype b conjugate vaccination) were detected between these 2 patient groups. Furthermore, UM-patients were not more prone to infections compared to M-patients, and therapy had no impact on the incidence and pattern of infections in either of the patient groups. The current findings within this patient cohort reveal that the worse outcome in the unmutated subgroup is not caused by more severe defects in immunity and increased susceptibility to infections when compared with the hypermutated group. It is thus conceivable that active immunization procedures such as vaccination can successfully be applied on patients with unmutated IgVH gene and advanced disease stage. 相似文献
106.
Connective tissue growth factor and its correlation to other growth factors in experimental granulation tissue 总被引:2,自引:0,他引:2
Connective tissue growth factor (CTGF) is upregulated in a variety of fibrotic disorders, probably secondary to the activation and production of transforming growth factor-beta (TGF-beta). We have studied the expression of CTGF in a rat wound-healing model using Northern blot, in situ hybridization, and immunohistochemistry. The expression of CTGF mRNA in Northern blot and immunohistochemistry were correlated to the expression of TGF-beta1 and platelet-derived growth factor (PDGF). Northern hybridization showed the maximum expression of CTGF mRNA on day 14, whereas TGF-beta1 expression was maximal on days 7 and 14 and the time-related changes were smaller than for CTGF. PDGF A and PDGF B mRNA expressions were at maximum on day 14 and on day 21, respectively. In situ hybridization showed that fibroblast-like cells expressed CTGF most intensively, expression declining rapidly after day 14. CTGF mRNA and protein were found in blood vessel cells during the first week. In immunohistochemistry, all growth factors were expressed by fibroblast-like cells, macrophage-like cells, and blood vessels but CTGF-positive cells were fewer and were more restricted on days 5 and 7. These results demonstrate that CTGF expression together with TGF-beta and PDGF are up-regulated in wound healing, and CTGF expression in blood vessels suggests that CTGF is involved in angiogenesis. 相似文献
107.
Kawashima S Peltomäki T Laine J Rönning O 《International journal of pediatric otorhinolaryngology》2002,63(2):119-127
OBJECTIVE: this study was aimed at characterizing the craniofacial structures, i.e. the facial skeleton, cranial base, dentition, pharyngeal airway space, and the hyoid bone position, in healthy preschool children without sleep-related breathing disorder. MATERIALS AND METHODS: from lateral cephalometric radiographs taken of 92 children for diagnostic purposes, 45 were selected for the present investigation on the basis of head position, and divided according to the classification of Siriwat and Jarabak (Angle Orthod. 55 (1985) 127) into groups representing counter-clockwise (CC), straight downward (SD), and clockwise (C) facial types. RESULTS: the findings showed that, in comparison with the other groups, CC is associated with larger facial taper and posterior facial height, smaller mandibular line angle, ramus position, lower facial height and cranial base angle. By a similar comparison, C is associated with larger mandibular line, gonial angles and convexity, and with a smaller L-1 to mandibular line angle. There were no significant differences in hyoid bone position among the three groups. However, the distance of the lower pharynx was smaller in CC than in C, while the tongue base of CC was noted to be in a posterior position. CONCLUSIONS: thus, the results indicate that there are significant differences in the madibular position and form among the present three groups of children. It is proposed that the objective of vertical facial control ought to be included in the treatment of preschool children with malocclusion and respiratory disorder. 相似文献
108.
Honkanen PB Kellomäki M Lehtimäki MY Törmälä P Mäkelä S Lehto MU 《Tissue engineering》2003,9(5):957-965
Swanson silicone implant is the "gold standard" of metacarpophalangeal joint reconstruction in rheumatoid arthritis (RA) patients. However, durability problems of silicone implants have led us to develop a new technique based on bioreconstructive implants. PLA96 (poly-L,D-lactide copolymer, L:D ratio of 96:4) scaffolds were engineered. Bioabsorption and substitution of porous PLA96 scaffold with living tissue eventually produce a neojoint. In the current prospective study, 23 RA patients (80 joints) were operated on, using PLA96 implants. Fifteen patients (54 joints) have been monitored for at least 1 year. Pain alleviation was well achieved. Range of motion improvement was emphasized to extension direction of functional arc. The average ulnar deviation was preoperatively 26 degrees, and at follow-up it was 6 degrees. Volar subluxation was noticeable in 56% of joints preoperatively and in 6% at 1-year follow-up. This is the first report of the formation of a living, functional joint in situ by means of a synthetic bioreconstructive joint scaffold. Results of this preliminary short-term study are comparable with previously published data on silicone arthroplasty. However, bioreconstructive prostheses can aid in preventing problems that occur with biostable prostheses. Tissue engineering has created a new era in the reconstruction of damaged joints. 相似文献
109.
Pukkila MJ Kellokoski JK Virtaniemi JA Kumpulainen EJ Johansson RT Halonen PM Kosunen AS Nuutinen J Kosma VM 《The Laryngoscope》2002,112(6):1084-1088
OBJECTIVE: To investigate the expression of inducible nitric oxide synthase (iNOS) in oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC) and its relation to p53 expression, histologic differentiation, clinical data, and prognosis. STUDY DESIGN: A retrospective survey. METHODS: Primary tumors for analyses were obtained from 118 patients diagnosed with SCC of the oropharynx or hypopharynx between 1975 and 1998 in eastern Finland. Immunohistochemical analysis was used to evaluate the expression of iNOS and p53. The expression pattern of iNOS was related to p53 expression, clinical data, and survival. RESULTS: High iNOS score was associated significantly with high nuclear p53 expression index (P = .006) and positive cytoplasmic p53 expression (P = .025). The score for iNOS expression was significantly lower in the largest (T4) tumors (P = .043). No association was seen between iNOS score and N or M class, tumor stage, or histologic differentiation. The score for iNOS expression was not related to overall survival. CONCLUSIONS: The expressions of iNOS and p53 seem to be inter-related in pharyngeal SCC, although the causality remains to be clarified. The expression of iNOS shows no prognostic value in pharyngeal SCC. 相似文献
110.
Immonen A Jutila L Könönen M Mervaala E Partanen J Puranen M Rinne J Ylinen A Vapalahti M 《Epilepsy research》2003,54(1):59-62
We report an illustrative case of presurgical evaluation for epilepsy surgery, where the three-dimensional reconstructed magnetic resonance imaging played a pivotal role in determining the exact location of the subdural strip electrodes in temporomesial area. The tip of one the frontal strip electrodes was actually recording the temporopolar ictal activity. This contributed conclusively to the decision for surgical treatment and to the excellent outcome. 相似文献