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91.
To evaluate three methods for digoxin dose adjustment in aged patients, we determined the plasma digoxin levels that would be attained in 87 aged patients with doses adjusted to the kidney function by means of three separate procedures. Mean patient age was: 79.0 +/- 6.3 years; creatinine clearance (Clc): 0.70 +/- 0.23 mL/Kg of lean body weight and minute; digoxinemia/dose ratio (RCpD): 0.421 +/- 0.237 Kg/L. The dose that would attain a digoxinemia of 1.2 ng/mL, calculating the elimination constant (K) and the volume of distribution (V) as linear functions of the Clc, so that K ranges between 0.173 and 0.462 days-1 and V between 4 and 10 L/Kg of lean body weight when the Clc varies from 0 to 110 mL/minute, was 2947 ng/Kg of lean body weight, coefficient of variation (CV): 25.2%. The digoxinemia that patients would have with this D, taking into account the individual RCpD, was 1.1 ng/mL, CV: 38.0%; with figures between 0.8 y 2.0 ng/mL and above 2.0 ng/mL in the 81.6% and the 0.0% of the patients (95% confidence intervals (95% CI): 72.2% to 88.4 and 0.0% to 4.6%), respectively. The precision and the bias were 0.43 and -0.06 ng/mL (95% CI: 0.38 to 0.48 and -0.16 to 0.03 ng/mL), respectively, and with this method the digoxinemia was not associated with the Clc. We concluded that the described method would lead to good results if digoxin has not been prescribed in order to control the cardiac frequency in the setting of auricular fibrilation. 相似文献
92.
93.
J. Pressmar H. Brinkmeier M. J. Seewald T. Naumann R. Rüdel 《Pflügers Archiv : European journal of physiology》1994,426(6):499-505
The free intracellular calcium concentration, [Ca2+]i, was studied in single myotubes using the fluorescent Ca2+ indicator fura-2. Myotubes cultured from satellite cells of small muscle specimens from Duchenne muscular dystrophy (DMD) patients were compared with human control myotubes and with myotubes cultured from MDX and control mouse muscle satellite cells. The resting [Ca2+]i levels in DMD and control myotubes were not significantly different, i. e. 104 ±26 nM (mean ± SD, n=190 cells from eight DMD patients) compared with 97±25 nM (175/seven controls) and were not significantly lower than the corresponding murine values (154±33 nM, n=135 MDX myotubes; 159±34 nM, n=135 controls). All myotubes reacted to 10 M acetylcholine or 40 mM KCl with fast transient increases of [Ca2+]i. After application of a hyposmotic (130 mOsm) solution, [Ca2+]i was increased 1.5- to 3-fold within 2–3 min, the DMD myotubes tending to stronger reactions (significantly higher [Ca2+]i in 2 out of 6 cases). The response was usually transient, [Ca2+]i decreasing to the initial level within 10 min. Gadolinium (50 M) reduced the response by 50%–70%, indicating that the osmotic shock increased Ca2+ influx. During exposure to high (15 mM) [Ca2+]e, [Ca2+]i of DMD and control cells was 1.5- to 2-fold higher. Adult muscle fibres from MDX mice and controls showed identical Ca2+ resting levels (n=45 fibres from three mice in each case), but did not respond to decreased external osmolarity with a change in [Ca2+]i. The results indicate that lack of dystrophin in muscle fibres does not necessarily lead to increased [Ca2+]i. It is suggested that increased [Ca2+]i is probably a secondary consequence of fibre damage. 相似文献
94.
Bruce F. Pennington Shelley D. Smith Lon R. Cardon Javier Gayán Valerie S. Knopik Richard K. Olson John C. DeFries 《American journal of medical genetics. Part A》2002,114(3):260-268
Comorbidity is pervasive among both adult and child psychiatric disorders; however, the etiological mechanisms underlying the majority of comorbidities are unknown. This study used genetic linkage analysis to assess the etiology of comorbidity between reading disability (RD) and attention‐deficit hyperactivity disorder (ADHD), two common childhood disorders that frequently co‐occur. Sibling pairs (N = 85) were ascertained initially because at least one individual in each pair exhibited a history of reading difficulties. Univariate linkage analyses in sibling pairs selected for ADHD from within this RD‐ascertained sample suggested that a quantitative trait locus (QTL) on chromosome 6p is a susceptibility locus for ADHD. Because this QTL is in the same region as a well‐replicated QTL for reading disability, subsequent bivariate analyses were conducted to test if this QTL contributed to comorbidity between the two disorders. Analyses of data from sib pairs selected for reading deficits revealed suggestive bivariate linkage for ADHD and three measures of reading difficulty, indicating that comorbidity between RD and ADHD may be due at least in part to pleiotropic effects of a QTL on chromosome 6p. © 2002 Wiley‐Liss, Inc. 相似文献
95.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1
96.
Arcos D del Real RP Vallet-Regí M 《Journal of biomedical materials research. Part A》2003,65(1):71-78
Three biphasic materials have been synthesized from a magnetic glass-ceramic (Si-Ca-Fe) and a bioactive sol-gel glass (Si-P-Ca). The ratios of glass-ceramic:sol-gel glass used in this work were 1:1, 2:1, and 5:1. These materials show bioactive and magnetic properties and can be used as thermoseeds for hyperthermia treatment of bone tumors. The sol-gel glass content affects the textural properties of the glass-ceramic, giving rise to porosity, which plays a fundamental role in the formation of an apatite-like layer on the surface. On the other hand, as the sol-gel glass content increases, the magnetic properties change due to the diffusion of Fe ions to the glassy phases of the biphasic materials. The biphasic nature of these materials allows the changing of both properties, depending on the requirements of the patient. 相似文献
97.
98.
PTEN mutations in endometrial carcinomas: a molecular and clinicopathologic analysis of 38 cases 总被引:23,自引:0,他引:23
PTEN mutations have been reported to be frequent in endometrioid carinomas of the endometrium (EEC). Some correlation has been found between PTEN mutations and the presence of microsatellite instability (MI) in EEC, but no convincing cause-effect relationship for such association has been offered. DNA of 38 patients with endometrial carcinoma (EC) was extracted from blood and from fresh-frozen and paraffin-embedded tumor tissue. PTEN mutations were detected by single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. Results were correlated with MI status and clinicopathologic data. PTEN mutations were detected in 17 tumors (44.7%), and they were more frequent in endometrioid (EEC) (17 of 33, 51.5%) than in nonendometrioid carcinomas (NEEC) (0 of 5, 0%). PTEN mutational spectrum differed between MI+ and MItumors. PTEN mutations were detected in 9 of 15 MI+ tumors (60%), but in only 8 of 23 MI- neoplasms (34.8%). In EC with MI, PTEN mutations were detected in short coding mononucleotide repeats (A)s and (A)6 in 4 of 9 carcinomas (44.4%). These results confirm that PTEN is an important target gene in endometrial carcinogenesis. The occurrence of PTEN mutations in short coding mononucleotide repeats in MI-positive tumors suggests that these mutations may be secondary to deficiencies in mismatch repair and gives some explanation for the frequent presence of PTEN mutations in these tumors. 相似文献
99.
Moreno Sabater A Moreno M Moreno FJ Eguiluz C van Rooijen N Benito A 《Parasitology research》2005,95(2):97-105
The main objective of this study was to determine whether a chemical immunomodulation protocol could reduce the resistance of NOD/LtSz-SCID mice to Plasmodium falciparum infection and provide an improved mouse model for screening the antimalarial activity of new compounds. This model was compared with the presently used immunodeficient Beige/Nude/Xid (BNX) mouse model, using the same protocol, in terms of percentage of infected mice, parasite development, leukocyte response and phagocytosis of P. falciparum infected cells in various organs. Our results show that the combination of the chemical immune modulation protocol with the genetic background of NOD/LtSz-SCID mice results in the development of long-lasting P. falciparum infection in a high percentage of mice. A comparison of the results obtained in the histological study for both mouse models suggests that the higher rate of success in NOD/LtSz-SCID mice could be related to the reduced macrophage recruitment developed in different tissues to remove the parasite from blood. 相似文献
100.
Relating cistrons and functions in bacteriophage PM2 总被引:1,自引:0,他引:1
An approach to correlate functions with cistrons in bacteriophage PM2 is presented. Two of the temperature-sensitive mutants obtained differed from the wild type in heat sensitivity and four differed in host range. Comparison of the electrophoretic patterns of DNA from cells infected at the restrictive temperature with those obtained in wildtype infection revealed that viral DNA bands were absent with three additional mutants. Complementation analysis assigned the four host range mutants to cistron I and the three mutants defective in DNA synthesis to cistron IV. Recombination frequencies were used to locate cistrons III and IV on the partial genetic map of PM2. 相似文献