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21.
Annet Lievense Sita Bierma-Zeinstra Boris Schouten Arthur Bohnen Jan Verhaar Bart Koes 《The British journal of general practice》2005,55(512):199-204
BACKGROUND: Trochanteric pain is the second most important diagnosis of hip problems presenting in primary care, but its incidence and prognosis in this context is largely unknown. AIM: To determine the 1- and 5-year prognoses of trochanteric pain and the predictive variables for consistent complaints. DESIGN OF THE STUDY: Retrospective cohort study. SETTING: One hundred and sixty-four patients (mean age = 55 years, 80% female) with incidental trochanteric pain in the years 1996 or 2000 were asked in 2001 for past and present symptoms of trochanteric pain. Therapeutic interventions, demographic factors and comorbidity were also investigated. METHOD: The databases of 39 GPs were screened in order to identify all incident cases with a suspicion of trochanteric pain in the years 1996 or 2000. These cases were sent a questionnaire. RESULTS: The incidence of trochanteric pain in primary care is 1.8 patients per 1000 per year. After 1 year at least 36% still suffered from trochanteric pain, and after 5 years this was 29%. Patients with osteoarthritis (OA) in the lower limbs had a 4.8-fold risk of persistent symptoms after 1 year, as compared to patients without OA. Patients who had received a corticosteroid injection had a 2.7-fold chance of recovery after 5 years, as compared with patients who had not received an injection. CONCLUSION: Trochanteric pain is shown to be a chronic disease in a substantial number of patients. The disorder is associated with much impairment when conducting daily activities. 相似文献
22.
Jacek Semenowicz Bogdan Koczy Przemys?aw Czuma Bart?omiej Pijet Tomasz Olszewski Roman Walo 《Chirurgia narzadów ruchu i ortopedia polska》2007,72(1):33-36
The Avantage double mobility press-fit cup was devised by Dr. Bousquet in the 70's to bring reasonable response to a problem of recurrent dislocation after total hip arthroplasty. The cup is attached to the femoral head by a bipolar polyethylene liner. The polyethylene liner moves freely inside a shiny--polished metal cup. The angular range of motion before impingement is increased by the mobility of the liner. The double connection (cup-liner, liner-head) reduces the stress on the metal cup and improve the stability of the prosthesis. The solution has proved to be efficient in reducing dislocation risk and maintains at the same time the appropriate range of motion. Between January 2004 and November 2005, 113 hip arthroplasties in 108 women with use of the double mobility cup were performed. The cemented version of the Avantage cup was inserted in 15 patients (mean age--76.9 years). Uncemented, HA coated implant was used in 98 patients (with mean age of 55 years). The mean follow-up was 20.4 months. No one patient was lost to follow-up. No postoperative dislocation was observed during follow-up. There was no unwanted leg lengthening greater than 1 cm. The Avantage cup may be indicated in any primary total hip arthroplasty especially in those with increased risk of postoperative dislocations. This cup enables a correct balance of the hip without a need of the unwanted lengthening of the leg. 相似文献
23.
W. Sperl G. Bart M. T. Vanier H. Christomanou I. Baldissera E. Steichen-Gersdorf E. Paschke 《Journal of inherited metabolic disease》1994,17(1):93-103
Summary We report a family with six patients suffering from a sphingomyelinase-deficient form of Niemann-Pick disease, all presenting with a visceral course of the disease. Retinal changes classified as macular halos in four members indicated neuronal storage and therefore an intermediate type of the disease. For further classification of the biochemical type, [choline-methyl-14C]sphingomyelin degradation studies were carried out in fibroblast cultures of all six members. The low degradation rates measured were similar to those usually found in the neuronopathic form (type A) of Niemann-Pick disease. This family illustrates the broad heterogeneity within the sphingomyelinase deficiency group of the Niemann-Pick disease. Apparently the finding of a low sphingomyelin degradation rate in fibroblast cultures does not necessarily imply a typical serious and lethal course of the disease. 相似文献
24.
25.
Maqsood Yaqub Ronald Boellaard Bart N M van Berckel Mirthe M Ponsen Mark Lubberink Albert D Windhorst Henk W Berendse Adriaan A Lammertsma 《Journal of cerebral blood flow and metabolism》2007,27(7):1397-1406
The purpose of this study was to compare different kinetic and semi-quantitative methods for analysing human [18F]FP-beta-CIT studies: plasma input models, simplified (SRTM) and full (FRTM) reference tissue models, standard uptake values (SUV) and SUV ratios (SUVr). Both simulations and clinical evaluations were performed to determine the effects of noise, scan duration and blood volume on Akaike model selection, and on precision and accuracy of estimated parameters. For typical noise levels (COV approximately 2.5%) and scan durations (<90 mins), simulations provided poor fits (Akaike criterion) in case of reversible plasma input models showing a relatively high number of outliers compared with the two-tissue irreversible model. Reference tissue models provided more reliable fits, which were nearly independent of noise and scan duration. For clinical data, two tissue irreversible and reversible plasma input models fitted striatum curves equally well (Akaike criterion). BP with plasma input models were less precise and contained more outliers than BP obtained with SRTM or FRTM. Among all methods tested, SRTM showed the highest contrast between patients and controls. When differentiating between patients and controls, SUVr performed almost equally well as SRTM, although contrast between striatum and background was lower. In conclusion, SRTM provided BP estimates with the highest precision and accuracy. Moreover, SRTM provided good contrast between patients and controls, and between striatum and background. SRTM is therefore the method of choice for quantitative [18F]FP-beta-CIT studies. SUVr might be an alternative for larger clinical trials. 相似文献
26.
Gayle M. Davey Sonya L. Schober Bart T. Endrizzi Angela K. Dutcher Stephen C. Jameson Kristin A. Hogquist 《The Journal of experimental medicine》1998,188(10):1867-1874
During T cell development, thymocytes which are tolerant to self-peptides but reactive to foreign peptides are selected. The current model for thymocyte selection proposes that self-peptide–major histocompatibility complex (MHC) complexes that bind the T cell receptor with low affinity will promote positive selection while those with high affinity will result in negative selection. Upon thymocyte maturation, such low affinity self-peptide–MHC ligands no longer provoke a response, but foreign peptides can incidentally be high affinity ligands and can therefore stimulate T cells. For this model to work, thymocytes must be more sensitive to ligand than mature T cells. Contrary to this expectation, several groups have shown that thymocytes are less responsive than mature T cells to anti-T cell receptor for antigen (TCR)/CD3 mAb stimulation. Additionally, the lower TCR levels on thymocytes, compared with T cells, would potentially correlate with decreased thymocyte sensitivity. Here we compared preselection thymocytes and mature T cells for early activation events in response to peptide–MHC ligands. Remarkably, the preselection thymocytes were more responsive than mature T cells when stimulated with low affinity peptide variants, while both populations responded equally well to the antigenic peptide. This directly demonstrates the increased sensitivity of thymocytes compared with T cells for TCR engagement by peptide–MHC complexes. 相似文献
27.
Bart D. Maes Wim Lemahieu Dirk Kuypers Pieter Evenepoel Willy Coosemans Jacques Pirenne Yves F. CH. Vanrenterghem 《American journal of transplantation》2002,2(10):989-992
Diarrhea is the most frequently reported adverse event in patients treated with mycophenolate mofetil. Twenty-six renal transplant patients on a mycophenolate mofetil-based immunosuppressive regime with persistent afebrile diarrhea were examined. Diarrhea caused a significant rise in FK-506 trough levels despite intake of stable doses, necessitating FK-506 dose reductions of 30% to obtain pre-diarrhea trough levels. In contrast, trough levels of cyclosporine A remained stable without dose adjustments. This suggests that absorption and/or metabolism is differentially altered for FK506 compared with cyclosporine A in patients with diarrhea. In nine patients mycophenolate mofetil was reduced or stopped because of persistent diarrhea without identifiable cause. This resulted in end-stage renal disease because of chronic rejection in two patients, and in acute rejection in two patients, all taking FK506 and steroids. Therefore, dose adjustments of FK506 in patients with diarrhea must be carefully monitored, especially when doses of mycophenolate mofetil are also reduced. 相似文献
28.
A Serda Kantarcio?lu Teun Boekhout G Sybren De Hoog Bart Theelen Ayhan Yücel Tuba R Ekmekci Bettina C Fries Reiko Ikeda Adem Koslu Kemal Altas 《Medical mycology》2007,45(2):173-181
Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification. 相似文献
29.
Mulders AG Laven JS Eijkemans MJ de Jong FH Themmen AP Fauser BC 《Human reproduction (Oxford, England)》2004,19(9):2036-2042
BACKGROUND: Anti-Müllerian hormone (AMH), produced by growing pre-antral and early antral ovarian follicles, has been shown to be a useful marker for ovarian ageing. Serum AMH concentrations are elevated during reproductive life in anovulatory women, especially in those patients exhibiting polycystic ovaries (PCO). The current study was designed to investigate whether the decrease in AMH serum concentrations over time is different comparing women with normogonadotrophic anovulation [World Health Organization (WHO) group 2 (including polycystic ovary syndrome (PCOS)] and normo-ovulatory controls. METHODS AND RESULTS: AMH serum levels were assessed on two occasions in 98 patients suffering from WHO 2 anovulatory infertility as well as in 41 normo-ovulatory premenopausal women. Median time interval between both visits was 2.6 years (range 0.3-9.0) for WHO 2 patients compared with 1.6 years (range 1.0-7.3) in controls. Serum AMH concentrations were significantly (P < 0.0001) elevated on both occasions in WHO 2 patients (AMH1, median = 7.5 microg/l, range 0.1-35.8; and AMH2, median = 6.7 microg/l, range 0.0-30.6) compared with controls (AMH1, median = 2.1 microg/l, range 0.1-7.4; and AMH2, median = 1.3 microg/l, range 0.0-5.0). Regression analysis, corrected for age, indicated a significant relative decrease in serum AMH concentrations over time for both groups (P < 0.001). However, the decline in serum AMH in WHO 2 patients was significantly less compared with controls (P = 0.03). CONCLUSION: The present longitudinal study shows that serum AMH concentrations decrease over time both in women presenting with WHO 2 anovulatory infertility and in normo-ovulatory controls. The decrease in WHO 2 patients is less pronounced despite distinctly elevated concentrations. This observation may suggest retarded ovarian ageing and hence a sustained reproductive life span in these patients. 相似文献
30.
Differential expression of extracellular matrix metalloproteinase inducer (CD147) in normal and ulcerated corneas: role in epithelio-stromal interactions and matrix metalloproteinase induction 总被引:12,自引:0,他引:12
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Gabison EE Mourah S Steinfels E Yan L Hoang-Xuan T Watsky MA De Wever B Calvo F Mauviel A Menashi S 《The American journal of pathology》2005,166(1):209-219
Extracellular matrix metalloproteinase inducer (EMMPRIN) was originally identified on the tumor cell surface as an inducer of matrix metalloproteinase (MMP) production in neighboring fibroblasts. Here we demonstrate a role for EMMPRIN in MMP induction during corneal wound healing. MMP and EMMPRIN expression was analyzed in normal and ulcerated human corneas, as well as in corneal epithelial and stromal cells in culture using confocal microscopy, zymography, immunoblots, and real-time polymerase chain reaction. In normal cornea EMMPRIN was predominantly expressed in the epithelium but was markedly induced in the anterior stroma of ulcerated corneas. This coincided with MMP-2 induction that co-localized with EMMPRIN at the epithelio-stromal boundary. The role of epithelial-stromal interaction in MMP induction was investigated in an in vitro co-culture system and demonstrated an induction and co-localization of EMMPRIN and MMP-2 in the fibroblasts at the interface with epithelial cells. Direct contact of fibroblasts with EMMPRIN-containing purified epithelial cell membranes also induced MMP-1, MMP-2, and EMMPRIN and this was inhibited by a blocking anti-EMMPRIN antibody, suggesting that EMMPRIN was primarily responsible for this induction. These findings, and the up-regulation of EMMPRIN by epidermal growth factor and transforming growth factor-beta, demonstrate a role for EMMPRIN in wound healing and suggest that sustained local up-regulation of EMMPRIN and MMPs in chronic situations in which healing is delayed may lead to excessive matrix degradation and corneal melts. 相似文献