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排序方式: 共有1637条查询结果,搜索用时 46 毫秒
1.
A case of Rubinstein‐Taybi syndrome associated with growth hormone deficiency in childhood 下载免费PDF全文
2.
R D Perrone T I Steinman G J Beck C I Skibinski H D Royal M Lawlor L G Hunsicker 《American journal of kidney diseases》1990,16(3):224-235
Assessment of glomerular filtration rate (GFR) with inulin is cumbersome and time-consuming. Radioisotopic filtration markers have been studied as filtration markers because they can be used without continuous intravenous (IV) infusion and because analysis is relatively simple. Although the clearances of 99mTc-diethylenetriamine-pentaacetic acid (DTPA), 169Yb-DTPA, and 125I-iothalamate have each been compared with inulin, rarely has the comparability of radioisotopic filtration markers been directly evaluated in the same subject. To this purpose, we determined the renal clearance of inulin administered by continuous infusion and the above radioisotopic filtration markers administered as bolus injections, simultaneously in four subjects with normal renal function and 16 subjects with renal insufficiency. Subjects were studied twice in order to assess within-study and between-study variability. Unlabeled iothalamate was infused during the second half of each study to assess its effect on clearances. We found that renal clearance of 125I-iothalamate and 169Yb-DTPA significantly exceeded clearance of inulin in patients with renal insufficiency, but only by several mL.min-1.1.73m-2. Overestimation of inulin clearance by radioisotopic filtration markers was found in all normal subjects. No differences between markers were found in the coefficient of variation of clearances either between periods on a given study day (within-day variability) or between the two study days (between-day variability). The true test variability between days did not correlate with within-test variability. We conclude that the renal clearance of 99mTc-DTPA, 169Yb-DTPA, or 125I-iothalamate administered as a single IV or subcutaneous injection can be used to accurately measure GFR in subjects with renal insufficiency; use of the single injection technique may overestimate GFR in normal subjects. 相似文献
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Dr. Andrew G. Bostom M.D. Dr. Anne L. Hume Pharm.D. Dr. Charles B. Eaton M.D. Dr. Joseph P. Laurino Ph.D. Ms. Lisa R. Yanek B.A. Ms. Mary S. Regan B.S. Mr. William H. McQuade M.P.H. Dr. Wendy Y. Craig Ph.D. Ms. Gayle Perrone M.B.A. Dr. Paul F. Jacques Sc.D. 《Pharmacotherapy》1995,15(4):458-464
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD. 相似文献
5.
M. Bertolotto G. Cecchini C. Martinoli R. Perrone G. Garlaschi 《European radiology》1996,6(5):637-639
A case of primary non-Hodgkin's lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge.
Correspondence to: M. Bertolotto 相似文献
6.
Puntoni Riccardo; Toninelli Fabrizia; Zhankui Li; Bonassi Stefano 《Carcinogenesis》1995,16(7):1465-1471
The existence of a dose-related increase of lung cancer riskin cigarette smokers has been indisputably established. Thisfinding, however, is not confirmed at low doses (< 5 cigarettes/day),there still being a lack of epidemiological data. The use ofmathematical models of carcinogenesis to extrapolate from higherdoses allows estimation of the risk for very light smokers.The present study has been designed to compare a set of mathematicalmodels, i.e. one-hit, two-stage, multi-stage, logit, probit,and Weibull, in extrapolating relative risks at low doses fromthe data of nine large cohort studies on cigarette smokers reportedin the IARC Scientific Monograph on tobacco smoking. All modelsevaluated, apart from the one-hit, achieved a good fit, withthe proportion of explained variance ranging between 61% and67%. The relative risk estimates for passive smokers from themost updated epidemiological studies were taken into accountto evaluate, on the basis of these models, the correspondingexposure in terms of cigarette equivalent smoked.These values ranged from 0.21 to 0.43 cigarettes/day for thetwo-stage and multistage model, while probit, logit and Weibullmodels, yielded estimates one or even two orders of magnitudelower. The authors emphasize the substantial agreement betweenthe estimates of cigarette equivalent9 based on the applicationof two-stage and multi-stage models to the epidemiological evidenceon the effect of passive smoking and to the data based on thecomparison of tobacco metabolites in active and passive smokers. 相似文献
7.
M Mottolese A Cianciulli I Venturo R Perrone Donnorso M Salzano M Benevolo G Bigotti P G Natali 《Diagnostic cytopathology》1992,8(2):153-160
The use of a selected panel of monoclonal antibodies (MoAb) to tumor associated antigens (TAA) in immunocytochemical (IIC) tests has been shown, in a preliminary study, to be a powerful diagnostic tool for the identification of the primary solid tumor causing metastatic effusion. Despite this improvement in a minority of neoplastic fluids a number of different causes may still determine false negative (FN) immunocytochemical diagnoses. The aim of the present study was to confirm the diagnostic accuracy of this panel of MoAb. This was done by analyzing in IIC tests a larger number of effusions and by evaluating whether the expansion in short term culture of those fluids with an uncertain malignant morphology could provide an adequate cellular substrate for immunocytodiagnosis. The analysis of 314 effusions confirmed the results of the pilot study and demonstrated that the combination of short term culture and immunocytochemical assays can further increase the sensitivity of this novel diagnostic procedure from 84.3% to 95.3%. 相似文献
8.
We report the case of a 48-year-old woman with multiple benign metastasizing leiomyomas in both lungs and a single retroperitoneal leiomyoma. The patient underwent surgical resection of the lesions 15 years after total hysterectomy for uterine myomas. Immunohistochemical studies performed on the retroperitoneal and pulmonary neoplasms showed them to be of mesenchymal derivation with smooth muscle differentiation; the samples were negative for HMB-45. Some histogenetic hypotheses for the multiple leiomyomas are presented. 相似文献
9.
A standard dosimetry procedure for 192Ir sources used for endovascular brachytherapy 总被引:1,自引:0,他引:1
Piermattei A Fidanzio A Azario L Russo A Perrone F Capote R Toni MP 《Physics in medicine and biology》2002,47(23):4205-4221
The experimental dosimetry of a high dose rate (HDR) 192Ir source used for the brachytherapy of peripheral vessels is reported. The direct determination of the reference air kerma rate Kr agrees, within the experimental uncertainty, with the results obtained by a well ionization chamber calibrated at the NIST and the manufacturer's certification. A highly sensitive (HS) radiochromic film (RCF), that presents only one active layer, was used for the source dosimetry in a water phantom. The adopted experimental set-up, with the source in its catheter positioned on the RCF plane, seems to have given better accuracy of the RCF optical density measurements. The agreement between the measurement of the dose rate constant DKr (10 mm, pi/2) and the literature data confirmed the coherence of the HS RCF calibration obtained by the kerma in air measurements. The RCF measurements supplied dosimetric information about the dose to water per reference air kerma rate D(r, theta)/Kr along the source transverse bisector axis, the radial dose function g(r) and the anisotropy function F(r, theta). The value D(2 mm, pi/2)/Kr = 22.4 +/- 1.2 cGy h(-1)/(microGy h(-1)) is supplied with a dose uncertainty that is essentially due to the indeterminacy of the source position in the catheter. The data of the radial and anisotropy functions have been compared with Monte Carlo determinations reported in the literature. 相似文献
10.
C Ferri C Bellini C De Angelis L De Siati A Perrone G Properzi A Santucci 《Journal of clinical pathology》1995,48(6):519-524
AIMS--To evaluate the behavior of plasma endothelin-1 in patients with chronic hypoxia. METHODS--Fifteen male patients (mean age 52.1 +/- 3.1 years) with mild chronic obstructive pulmonary disease (COPD) were studied. Twelve healthy men (mean age 48.3 +/- 5.4 years) served as controls. Both patients and controls underwent standard pulmonary function tests, echocardiographic evaluation, and arterial blood gas evaluation. Blood samples for endothelin-1 assay were taken from a previously incannulated antecubital vein after 60 minutes of rest in the supine position. Endothelin-1 was measured by radioimmunoassay after extraction from plasma. RESULTS--Patients with chronic hypoxia had lower PaO2 values (66.1 +/- 6.2 mmHg) than controls (83.8 +/- 2.7 mmHg) but PaCO2 values were similar (38.1 +/- 2.5 v 36.7 +/- 3.1 mmHg, respectively). Arterial pulmonary pressure, therefore, was higher in patients (18.1 +/- 3.7 mmHg) than in controls (10.4 +/- 2.7 mmHg) as were circulating endothelin-1 concentrations (1.22 +/- 0.36 v 0.57 +/- 0.1 pg/ml). Furthermore, plasma endothelin-1 concentrations were negatively correlated with PaO2 and directly correlated with pulmonary pressure levels. No significant correlations were found in controls. CONCLUSIONS--These results show a clear relation between chronic hypoxia and circulating endothelin-1 concentrations. Therefore, chronic hypoxia may be regarded as an important stimulus for endothelin-1 release and as one of the main contributors to increased vasoconstriction in the vascular pulmonary bed which often accompanies lung disease. 相似文献