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排序方式: 共有608条查询结果,搜索用时 15 毫秒
21.
Semen parameters in a fertile versus subfertile population: a need for change in the interpretation of semen testing 总被引:6,自引:14,他引:6
Ombelet W; Bosmans E; Janssen M; Cox A; Vlasselaer J; Gyselaers W; Vandeput H; Gielen J; Pollet H; Maes M; Steeno O; Kruger T 《Human reproduction (Oxford, England)》1997,12(5):987-993
This prospectively designed study was conducted to compare a fertile and a
subfertile population so as to define normal values for different semen
parameters. Semen analyses were performed according to the World Health
Organization (WHO) guidelines, except for sperm morphology (strict
criteria). In the fertile population (n = 144), all patients had recently
achieved pregnancy, within 12 months of unprotected coitus. As subfertile
controls we examined semen samples from 143 consecutive men attending our
infertility clinic during the same study period. Couples with tubal factor
infertility and/or ovulatory disorders were excluded from our study. Using
receiver operating characteristic (ROC) curve analysis we determined the
diagnostic potential and cut-off values for single and combined sperm
parameters. Sperm morphology scored best, with a value of 78% (area under
the ROC curve). Summary statistics showed a shift towards abnormality for
most semen parameters in the subfertile population. Using the 10th
percentile of the fertile population as the cut-off value, the following
results were obtained: 14.3 x 10(6)/ml for sperm concentration, 28% for
progressive motility and 5% for sperm morphology. Using ROC analysis,
cut-off values were 34 x 10(6)/ml, 45% and 10% respectively. Cut-off values
for normality were different from those described in the WHO guidelines.
Routine bacterial and non- bacterial cultures turned out to be of little
prognostic value.
相似文献
22.
Effect of exercise on coronary endothelial function in patients with coronary artery disease 总被引:36,自引:0,他引:36
Hambrecht R Wolf A Gielen S Linke A Hofer J Erbs S Schoene N Schuler G 《The New England journal of medicine》2000,342(7):454-460
BACKGROUND: Studies of the cardioprotective effects of exercise training in patients with coronary artery disease have yielded contradictory results. Exercise training has been associated with improvement in myocardial perfusion even in patients who have progression of coronary atherosclerosis. We therefore conducted a prospective study of the effect of exercise training on endothelial function in patients with coronary artery disease. METHODS: We randomly assigned 19 patients with coronary endothelial dysfunction, indicated by abnormal acetylcholine-induced vasoconstriction, to an exercise-training group (10 patients) or a control group (9 patients). To reduce confounding, patients with coronary risk factors that could be influenced by exercise training (such as diabetes, hypertension, hypercholesterolemia, and smoking) were excluded. In an initial study and after four weeks, the changes in vascular diameter in response to the intracoronary infusion of increasing doses of acetylcholine (0.072, 0.72, and 7.2 microg per minute) were assessed. The mean peak flow velocity was measured by Doppler velocimetry, and the diameter of epicardial coronary vessels was measured by quantitative coronary angiography. RESULTS: In the initial study, the two groups had similar vasoconstrictive responses to acetylcholine. After four weeks of exercise training, coronary-artery constriction in response to acetylcholine at a dose of 7.2 microg per minute was reduced by 54 percent (from a mean [+/-SE] decrease in the luminal diameter of 0.41+/-0.05 mm in the initial study to a decrease of 0.19+/-0.07 mm at four weeks; P<0.05 for the comparison with the change in the control group). In the exercise-training group, the increases in mean peak flow velocity in response to 0.072, 0.72, and 7.2 microg of acetylcholine per minute were 12+/-7, 36+/-11, and 78+/-16 percent, respectively, in the initial study. After four weeks of exercise, the increases in response to acetylcholine were 27+/-7, 73+/-19, and 142+/-28 percent (P<0.01 for the comparison with the control group). Coronary blood-flow reserve (the ratio of the mean peak flow velocity after adenosine infusion to the resting velocity) increased by 29 percent after four weeks of exercise (from 2.8+/-0.2 in the initial study to 3.6+/-0.2 after four weeks; P<0.01 for the comparison with the control group). CONCLUSIONS: Exercise training improves endothelium-dependent vasodilatation both in epicardial coronary vessels and in resistance vessels in patients with coronary artery disease. 相似文献
23.
Nonlinear viscous properties of stretch and unloading reflexes in the human wrist were examined using constant-velocity ramp stretches and releases in the range between 5 and 500 mm/s. Subjects were asked to oppose an initial flexor preload and were instructed not to intervene voluntarily when the changes in position were applied. Electromyographic (EMG) activity and net force exerted by the wrist were measured. Although subjects were instructed not to intervene to the applied stretches, even well-practiced subjects sometimes showed unintended triggered reactions, which character could be assisting or resisting. A trial comparison method was used to detect and eliminate responses contaminated by unintended reactions. Ramp stretches further loaded the preloaded flexor muscles. Responses of EMG and force increased steeply initially but after about 1-cm displacement, the slope of these responses decreased to a lower value and remained constant during the remainder of the 5-cm ramp. For higher stretch velocities, the magnitudes and slopes of the responses of EMG and force increased but less than proportionally with ramp velocity. Except for the initial transient, EMG in the loaded flexor muscles and force responses could be described by a product relationship between a linear position-related term and a low fractional power of velocity, after a correction was made for delays in the reflex arc. Mean value of the exponent in the power function of velocity was 0.3 for EMG and 0.17 for force. For higher preloads, incremental responses of force to constant-velocity stretches, plotted as a function of wrist position, shifted to higher values and the slope of increase of force with position became somewhat steeper. This upward shift of the force trace reflects a change of apparent threshold of the stretch reflex. Ramp releases shortened and unloaded the preloaded flexor muscles and stretched the initially inactive extensor muscles. Flexor EMG activity declined progressively with a time course that was independent of velocity. Extensor EMG response depended on preload. At high preloads, there was no activity except for some bursting at the highest velocities. At low preloads, EMG activity was initially absent but started part way through the ramp. The increase of activity was somewhat greater for higher ramp velocities. Force responses to shortening ramps depended on preload. At high preloads, force responses superimposed at all of the low velocities but fell to slightly lower forces at the higher velocities. At low preloads, force traces again superimposed for low velocities and at high velocities only during the initial part of the response.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
24.
Oyen RH; Gielen JL; Van Poppel HP; Verbeken EK; Van Damme BJ; Baert LV; Baert AL 《Radiology》1988,169(3):705-707
Abdominal radiography, excretory urography, retrograde pyelography, and computed tomography were performed in two patients who had undergone retrograde pyelography with thorium dioxide (Thorotrast) approximately 40 years ago. Both patients developed a transitional cell carcinoma due to suburothelial thorium deposition. Typical thorium densities were demonstrated at CT in the peripelvicalyceal area as well as in retroperitoneal lymph nodes. Elderly patients in whom radiographic examination reveals retained Thorotrast in the kidney should be followed up because of the high risk of renal carcinoma. 相似文献
25.
S. Verschueren E. Gielen T. W. O’Neill S. R. Pye J. E. Adams K. A. Ward F. C. Wu P. Szulc M. Laurent F. Claessens D. Vanderschueren S. Boonen 《Osteoporosis international》2013,24(1):87-98
Summary
The aim of this study was to determine the relationship between reduced muscle mass (sarcopenia) and areal bone mineral density (BMDa) in middle-aged and elderly community-dwelling European men. Men with sarcopenia had significantly lower BMDa and were more likely to have osteoporosis compared with men without sarcopenia.Introduction
In men, the relationship between reduced muscle mass (sarcopenia) and BMDa is unclear. This study aimed to determine this relationship in middle-aged and elderly community-dwelling men.Methods
Men aged 40–79 years from the Manchester (UK) and Leuven (Belgium) cohorts of the European Male Ageing Study were invited to attend for assessment including dual-energy X-ray absorptiometry, from which appendicular lean mass (aLM), fat mass (FM) and whole-body, spine and hip BMDa were determined. Relative appendicular skeletal muscle mass (RASM) was calculated as aLM/height². Muscle strength was assessed in subjects from Leuven. Sarcopenia was defined by RASM at <7.26 kg/m² and by the recent definition of the European Working Group on Sarcopenia in Older People (RASM at <7.26 kg/m2 plus low muscle function). Linear regression was used to determine the associations between aLM, FM, muscle strength and BMDa and logistic regression to determine the association between sarcopenia and osteoporosis.Results
Six hundred seventy-nine men with a mean age of 59.6 (SD?=?10.7), contributed data to the analysis; 11.9 % were sarcopenic by the conventional definition. After adjustment for age and centre, aLM, RASM and FM were positively associated with BMDa. Men with RASM at <7.26 kg/m² had significantly lower BMDa compared with those with RASM at ≥7.26 kg/m2. In a multivariable model, aLM was most consistently associated with BMDa. Men with sarcopenia were more likely to have osteoporosis compared with those with normal RASM (odds ratio?=?3.0; 95 % CI?=?1.6–5.8).Conclusions
Sarcopenia is associated with low BMDa and osteoporosis in middle-aged and elderly men. Further studies are necessary to assess whether maintaining muscle mass contributes to prevent osteoporosis. 相似文献26.
27.
Clemens?SeidelEmail authorView authors OrcID profile André?O.?von Bueren Sabrina?Bojko Marion?Hoffmann Torsten?Pietsch Gerrit?H.?Gielen Monika?Warmuth-Metz Brigitte?Bison Rolf?D.?Kortmann Christof?M.?Kramm 《Strahlentherapie und Onkologie》2018,194(3):215-224
Purpose
As the efficacy of all pediatric high-grade glioma (HGG) treatments is similar and still disappointing, it is essential to also investigate the toxicity of available treatments.Methods
Prospectively recorded hematologic and nonhematologic toxicities of children treated with radiochemotherapy in the HIT GBM-C/D and HIT-HGG-2007 trials were compared. Children aged 3–18 years with histologically proven HGG (WHO grade III and IV tumors) or unequivocal radiologic diagnosis of diffuse intrinsic pontine glioma (DIPG) were included in these trials. The HIT-HGG-2007 protocol comprised concomitant radiochemotherapy with temozolomide, while cisplatinum/etoposide (PE) and PE plus ifosfamide (PEI) in combination with weekly vincristine injections were applied during radiochemotherapy in the HIT GBM-C/D protocol.Results
Regular blood counts and information about cellular nadirs were available from 304 patients (leukocytes) and 306 patients (thrombocytes), respectively. Grade 3–4 leukopenia was much more frequent in the HIT GBM-C/D cohort (n = 88, 52%) vs. HIT-HGG-2007 (n = 13, 10%; P <0.001). Grade 3–4 thrombopenia was also more likely in the HIT GBM-C/D cohort (n = 21, 12% vs. n = 3,2%; P <0.001). Grade 3–4 leukopenia appeared more often in children aged 3–7 years (n = 38/85, 45%) than in children aged 8–12 years (n = 39/120, 33%) and 13–18 years (24/100, 24%; P =0.034). In addition, sickness was more frequent in the HIT GBM-C/D cohort (grade 1–2: 44%, grade 3–4: 6% vs. grade 1–2: 28%, grade 3–4: 1%; P <0.001).Conclusion
Radiochemotherapy involving cisplatinum-based polychemotherapy is more toxic than radiotherapy in combination with temozolomide. Without evidence of differences in therapeutic efficacy, the treatment with lower toxicity, i.?e., radiotherapy with temozolomide should be used.28.
Pieter Van Dyck Christoph Kenis Filip M. Vanhoenacker Valérie Lambrecht Kristien Wouters Jan L. Gielen Lieven Dossche Paul M. Parizel 《Knee surgery, sports traumatology, arthroscopy》2014,22(6):1376-1384
Purpose
The aim of this prospective study was to compare routine MRI scans of the knee at 1.5 and 3 T obtained in the same individuals in terms of their performance in the diagnosis of cartilage lesions.Methods
One hundred patients underwent MRI of the knee at 1.5 and 3 T and subsequent knee arthroscopy. All MR examinations consisted of multiplanar 2D turbo spin-echo sequences. Three radiologists independently graded all articular surfaces of the knee joint seen at MRI. With arthroscopy as the reference standard, the sensitivity, specificity, and accuracy of 1.5- and 3-T MRI for detecting cartilage lesions and the proportion of correctly graded cartilage lesions within the knee joint were determined and compared using resampling statistics.Results
For all readers and surfaces combined, the respective sensitivity, specificity, and accuracy for detecting all grades of cartilage lesions in the knee joint using MRI were 60, 96, and 87 % at 1.5 T and 69, 96, and 90 % at 3 T. There was a statistically significant improvement in sensitivity (p < 0.05), but not specificity or accuracy (n.s.) for the detection of cartilage lesions at 3 T. There was also a statistically significant (p < 0.05) improvement in the proportion of correctly graded cartilage lesions at 3 T as compared to 1.5 T.Conclusion
A 3-T MR protocol significantly improves diagnostic performance for the purpose of detecting cartilage lesions within the knee joint, when compared with a similar protocol performed at 1.5 T.Level of evidence
III. 相似文献29.
Waninge A Rook RA Dijkhuizen A Gielen E van der Schans CP 《Research in developmental disabilities》2011,32(2):613-620
Caregivers of persons with profound intellectual and multiple disabilities (PIMD) often describe the quality of the daily movements of these persons in terms of flexibility or stiffness. Objective outcome measures for flexibility and stiffness are muscle tone or level of spasticity. Two instruments used to grade muscle tone and spasticity are the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale (MTS). To date, however, no research has been performed to determine the psychometric properties of the MAS and MTS in persons with PIMD. Therefore, the purpose of this study was to determine the feasibility, test-retest reliability, and interrater reliability of the MAS and MTS in persons with PIMD. We assessed 35 participants on the MAS and MTS twice, first for the test and second a week later for the retest. Two observers performed the measurements. Feasibility was assessed based on the percentage of successful measurements. Test-retest and interrater reliability were determined by using the Wilcoxon signed rank test, intraclass correlation coefficients (ICC), Spearman's correlation, and either limits of agreement (LOA) or quadratically weighted kappa. The feasibility of the measurements was good, because an acceptable percentage of successful measurements were performed. MAS measurements had substantial to almost perfect quadratically weighted kappa (>0.8) and an acceptable ICC (>0.8) for both inter- and intrarater reliability. However, MTS measurements had insufficient ICCs, Spearman's correlations, and LOAs for both inter- and interrater reliability. Our data indicated that the feasibility of the MAS and MTS for measuring muscle tone in persons with PIMD was good. The MAS had sufficient test-retest and interrater reliability; however, the MTS had an insufficient test-retest and interrater reliability in persons with PIMD. Thus, the MAS may be a good method for evaluating the quality of daily movements in persons with PIMD. Providing test administrators with training and clear instructions will improve test reliability. 相似文献
30.
This is a case report of a contact allergic reaction on the face due to a skin cleansing product containing the amphoteric surfactant sodium cocoamphoacetate, occurring in an atopic woman with multiple contact sensitivities. Because of its weak irritant properties, this surfactant is widely used in cosmetic products intended to be used for sensitive skin, including products for intimate, and baby hygiene. 相似文献