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OBJECTIVES: To evaluate the reliability (intertrial, interevaluator) and the concurrent validity of strength measurements obtained with a chair-fixed dynamometer and to recommend a clinical protocol that minimizes standard error of measurement (SEM). DESIGN: Within-session repeated measures of maximal static strength of knee flexors and extensors at 30 degrees and 60 degrees of flexion on the chair-fixed and Cybex dynamometers. SETTING: Ambulatory physiotherapy department of a rehabilitation hospital. PARTICIPANTS: Convenience sample of 50 subjects with total hip (n=25) or knee (n=25) arthroplasty. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Reliability was quantified by indices of dependability and corresponding SEMs estimated with the generalizability theory, whereas coefficients of correlation were used to assess the validity. RESULTS: Indices of dependability confirmed excellent intertrial (0.98-1.00) and a very good interevaluator (.92-.99) reliability for the strength measures obtained for different movements and positions. An average of 3 trials minimized the magnitude of the SEMs (>2 Nm for all measurements). When comparing the strength values obtained with the Cybex dynamometer to those measured with the chair-fixed dynamometer, strongest relations were attained when the tested knee was positioned at 60 degrees compared with 30 degrees for subjects with a total knee (.78-.92 vs .87-.93) or hip (.73-.85 vs .86-.91) arthroplasty. CONCLUSIONS: A clinical protocol averaging 3 trials with the knee positioned at 60 degrees after a familiarization period, both for knee flexors and extensors, performed by a trained therapist is recommended to minimize measurement errors on strength values measured with the chair-fixed dynamometer.  相似文献   
23.
Single-step maternal serum screening (MSS) in the first (1MSS) or second (2MSS) trimester at maternal age > or =35 years was evaluated in the North Belgian region Flanders, where difficulties are encountered in the general introduction of combined or integrated screening algorithms. The fetal aneuploidy screening database of General Medical Laboratory AML in Antwerp was searched for 2MSS tests between 1992 and 1999 (alpha-fetoprotein, beta-human chorionic gonadotropin (beta-HCG) and unconjugated estriol, cut-off 1:300) and for 1MSS tests between 1999 and 2003 (free beta-HCG and pregnancy-associated plasma protein A, cut-off 1:85). At > or =35 years, the detection rate for trisomy 21 (DR) was 93.8% (15/16) for 2MSS and the screen-positive rate (SPR) was 24.5% (504/2061). For 1MSS, these figures were 85.7% (6/7) and 17.7% (109/615) respectively. To detect one trisomy 21, missed by MSS at > or =35 years of age, an additional number of 1,557 and 506 primary invasive procedures would be needed for 2MMS and 1MSS respectively. We conclude that the performance of both single-step 1MSS and 2MSS at maternal age > or =35 years in Flanders is excellent, even without the combination with ultrasound parameters or integration of first and second trimester parameters. The simplicity of both methods allows to consider them valuable options for fetal aneuploidy screening at advanced maternal age, until high quality combined or integrated screening is accessible to all pregnant women in Belgium.  相似文献   
24.
The promise of pharmacogenetics is to elucidate the inherited basis of differences between individual responses to drugs, in order to identify the right drug and dose for each patient. Genetic polymorphisms are implicated in the interindividual variability of the pharmacokinetic or pharmacodynamic characteristics of immunosuppressive drugs. The first pharmacogenetic trait identified was monogenic, and concerned the prototypic example of thiopurine methyltransferase (TPMT) implicated in azathioprine metabolism. Individuals with low TPMT activity, inherited in an autosomal codominant fashion, are at risk of drug-induced myelosuppression. TPMT activity determination and DNA-based tests are now used in clinical practice. It has been also demonstrated that there is a link between the polymorphisms of the cytochrome P450 3A5, 3A4 and the multidrug resistance-1 (MDR1) genes, and the daily dose necessary to achieve adequate blood tacrolimus levels. Analysis of MDR1 haplotypes or using the association of the different genes might further improve predictions. Since genotyping methods improve rapidly, it will soon be easy to test for thousands of single nucleotide polymorphisms in one assay. Present challenges are to determine the genes of interest and to validate such determination prospectively in clinical practice.  相似文献   
25.
The knowledge of the roles and origins of different gonadotrophin-releasing hormone (GnRH) systems could greatly contribute to improve the understanding of mechanisms involved in the physiological control of early development, puberty and spawning. Thus, in this study, we have analyzed the distribution of the cells expressing salmon GnRH, seabream GnRH and chicken GnRH-II forms in the brain and pituitary of developing sea bass using specific antibodies to their corresponding GnRH-associated peptides. The first prepro-chicken GnRH-II-immunoreactive cells arose in the germinal zone of the third ventricle at 4 days after hatching, increasing their number from days 10 to 30, in which they adopted their adult position. The prepro-chicken GnRH-II-immunoreactive fibers became conspicuous in the first week and from day 26 they reached almost all brain areas, especially the hindbrain, being never detected in the pituitary. First prepro-salmon GnRH-immunoreactive cells were detected in the olfactory placode at day 7 after hatching and reached the olfactory bulbs at day 10. Migrating prepro-salmon GnRH cells arrived at the ventral telencephalon at day 15, and became apparent in the preoptic area from day 45. The prepro-salmon GnRH innervation was more evident in the forebrain and increased notably between 10 and 30 days, at which fibers already extended from the olfactory bulbs to the medulla. A few prepro-salmon GnRH-immunoreactive fibers were observed in the pituitary from day 30. The prepro-seabream GnRH-immunoreactive cells were first detected at day 26 in the rostral olfactory bulbs. On day 30, prepro-seabream GnRH-immunoreactive cells were also present in the ventral telencephalon, reaching the preoptic area and the hypothalamus at 45 and 60 days, respectively. The prepro-seabream GnRH innervation appeared restricted to the ventral forebrain, increasing notably during the sixth week, when fibers also reached the pituitary. A significant prepro-seabream GnRH innervation was not detected in the pituitary until day 60.  相似文献   
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27.
Multicentric Castleman's disease (MCD) is a rare systemic lymphoproliferative disorder with too few patient series reported in the literature to have a clear idea about the etiology, outcome and the best treatment available. Systemic reactive amyloidosis is a very rare complication of MCD and its presence worsens the prognosis. We report a case of a 28-year-old patient with plasma-cell type, human immunodeficiency virus (HIV)-negative and human herpesvirus-8 (HHV-8)-negative MCD who responded to treatment with chemotherapy and the anti-CD20 monoclonal antibody, rituximab. Anti-CD20 therapy could be an interesting adjunctive treatment in MCD.  相似文献   
28.
OBJECTIVE: Our first objective was to determine a blood lactate threshold predictive of survival in human immunodeficiency virus patients experiencing lactic acidosis related to nucleoside analogs, and second, to test l-carnitine for the treatment of patients exceeding that threshold. DESIGN: a) Retrospective study using data from personal and published observations to determine the lactate threshold between survivors and nonsurvivors in human immunodeficiency virus patients being treated with nucleoside analogs. b) Prospective multicenter open trial to test l-carnitine treatment of human immunodeficiency virus patients receiving nucleoside analogs. SETTING: Medical intensive care units of four teaching hospitals and one general hospital. PATIENTS: Retrospective analysis of data from 39 human immunodeficiency virus patients (five personal cases and 34 patients from the literature) receiving nucleoside-analog treatment from which lactate values were available. An additional six patients with high lactate values were included as a pilot study testing the use of l-carnitine therapy. MEASUREMENTS AND MAIN RESULTS: An initial lactate level of 9 mmol/L, which gave good positive and negative predictive values, was determined as a threshold between survivors and nonsurvivors for the patients receiving nucleoside-analog treatment. Six patients with initial lactate levels >10 mmol/L were prospectively treated with l-carnitine; three survived beyond the end of the study. CONCLUSIONS: The blood lactate levels in human immunodeficiency virus patients receiving nucleoside-analog therapy can predict mortality in these patients. The preliminary data from this pilot study suggest that l-carnitine may be helpful for patients who have nucleoside-analog-related lactic acidosis with blood lactate levels >10 mmol/L. Further studies will be necessary to affirm the therapeutic efficacy of l-carnitine in this setting.  相似文献   
29.
BACKGROUND: We previously reported that treatment of patients with symptomatic advanced non-small cell lung cancer with single agent Gemcitabine (GEM) resulted in a superior clinical-benefit response rate (RR) compared to cisplatin-based combination chemotherapy. We now report the detailed individual symptom control analysis, and the influence of cisplatin-use, age, performance status (PS) and duration of treatment. PATIENTS AND METHODS: Patients received either GEM (1000 mg/m(2), days 1, 8 and 15) or cisplatin (100 mg/m(2), day 1) plus Vindesine (3 mg/m(2), days 1 and 15) (PV), both every 4 weeks. Scores of 9 symptoms were listed weekly by the patient on visual analogue scales. Improvement of a symptom was defined as 2 consecutive cycles of improvement over baseline. RESULTS: Baseline symptoms in the 169 patients were well balanced between the 2 arms (84 GEM, 85 PV). Both patients with objective response and disease stabilisation had clearly better symptom control than those with disease progression. Symptom control in both arms was similar for 'disease-specific' symptoms such as cough, dyspnea, pain or haemoptysis. Compared to PV, a significantly larger number of GEM-patients had better scores for 'constitutional' items such as anorexia (P=0.007), ability to carry on with daily activities (P=0.04) and overall impression of quality-of-life (P=0.008). Symptom control was very similar in younger (<65 years) versus older (>/=65 years) patients, and only slightly better in those with a Karnofsky PS >/=80% compared to those <80%. Most of the symptom improvement occurred in the first 3 cycles, with some further symptom improvement in the following cycles in the GEM-arm only. CONCLUSIONS: Both GEM and PV yield a symptom control rate much higher than expected by the objective tumour RR. GEM is equally effective in controlling 'disease-specific' symptoms, but superior in controlling 'constitutional' symptoms. Most of the symptom control was achieved during the first 3 cycles of treatment, with some further improvement thereafter in the GEM-arm only.  相似文献   
30.
PURPOSE: Primary adenocarcinoma of the anus is a rare tumor. The current standard treatment consists of abdominoperineal resection (APR). The aim of this Rare Cancer Network study was to evaluate the prognostic factors and outcome after the three most commonly used treatment approaches. METHODS AND MATERIALS: This multicenter study collected data from 82 patients: 15 with T1 (18%), 34 with T2 (42%), 22 with T3 (27%), and 11 with T4 (13%) tumors according to the TNM classification (International Union Against Cancer, 1997). Patients were separated into, and analyzed according to, three treatment categories: radiotherapy/surgery (RT/S group, n = 45), combined radiochemotherapy (RT/CHT group, n = 31), and APR alone (APR group, n = 6). The main patient characteristics were evenly distributed among the three groups. RESULTS: The actuarial locoregional relapse rate at 5 years was 37%, 36%, and 20%, respectively, in the RT/S, RT/CHT, and APR groups (RT/S vs. RT/CHT, p = 0.93; RT/CH vs. APR, p = 0.78). The 3-, 5-, and 10-year overall survival rate was 47%, 29%, and 23% in the RT/S group, 75%, 58%, and 39% in the RT/CHT group, and 42%, 21%, and 21% in the APR group (RT/CHT vs. RT/S, p = 0.027), respectively. The 5- and 10-year disease-free survival rate was 25% and 18% in the RT/S group, 54% and 20% in the RT/CHT group, and 22% and 22% in the APR group (RT/CHT vs. RT/S, p = 0.038), respectively. Multivariate analysis revealed four independent prognostic factors for survival: T stage, N stage, histologic grade, and treatment modality. CONCLUSION: Primary adenocarcinoma of the anal canal requires rigorous management. Multivariate analysis showed that T and N stage, histologic grade, and treatment modality are independent prognostic factors for survival. We observed better survival rates after combined RT/CHT. We also recommend using APR only for salvage treatment.  相似文献   
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