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排序方式: 共有8610条查询结果,搜索用时 15 毫秒
21.
Juan Francisco Sánchez Muñoz-Torrero Paloma Barquilla Raul Velasco Maria del Carmen Fernández Capitan Nazaret Pacheco Lucia Vicente Jose Luis Chicón Sara Trejo Jose Zamorano Alicia Lorenzo Hernandez 《European journal of clinical pharmacology》2010,66(12):1257-1264
Objectives
This study was designed to assess the prevalence of adverse drug reactions (ADRs) in the internal medicine wards of two teaching Hospitals, identify the most common ADRs, the principal medications involved, and determine the risk factors implicated in the occurrence of such ADRs. 相似文献22.
23.
Relation between histological findings on early repeat right ventricular biopsy and ventricular function in patients with myocarditis 总被引:3,自引:0,他引:3
Histological findings on repeat endomyocardial biopsy and changes in left ventricular ejection fraction early during immunosuppressive treatment were studied in 20 patients with documented myocarditis. All patients presented with heart failure of less than six months' duration and a left ventricular ejection fraction of less than or equal to 0.40. Repeat biopsy and assessment of ventricular function were performed at a mean (SEM) of 79 (17) days after the initial biopsy. At repeat biopsy eight patients had evidence of ongoing myocarditis and 12 showed resolved myocarditis. In eight (66%) of the 12 patients with resolved myocarditis ventricular function had improved significantly. Left ventricular ejection fraction also improved significantly in four of eight patients during treatment despite ongoing myocardial inflammation. Regardless of the histological findings on repeat biopsy, early improvement in ejection fraction was associated with an excellent long term prognosis--that is 83% survived for at least three years. Histological resolution of myocarditis during immunosuppressive treatment is not a prerequisite for improvement in ventricular function; and changes in left ventricular ejection fraction during the first three months of treatment are predictive of clinical outcome. 相似文献
24.
Distribution of Hepatitis B Virus Genotypes in Two Different Pediatric Populations from Argentina 总被引:12,自引:2,他引:10 下载免费PDF全文
V. A. Mbayed J. L. Lpez P. F. S. Telenta G. Palacios I. Badía A. Ferro C. Galoppo R. Campos 《Journal of clinical microbiology》1998,36(11):3362-3365
Differences in pathogenesis and the probability of becoming a chronic carrier depend on the age at which hepatitis B virus (HBV) infection is acquired, ranging from 82% in infants less than 6 months of age to 15 to 30% in older children. HBV genotypes from 22 pediatric patients from two areas that differ in prevalence have been determined. Phylogenetic analysis shows a clear difference between the genotype distribution in Buenos Aires, a low-prevalence area, and that found in Gualeguay, Entre Ríos, a high-prevalence area. While the analysis allocated the sequences in the Buenos Aires group to genotypes A (36%), D (9%), and F (55%), the Gualeguay group presented exclusively genotype A isolates with very low nucleotide divergence, which suggests a strong founder viral population. The high prevalence of genotype F in the Buenos Aires group and its high intragroup heterogeneity agree with the American origin of this genotype. 相似文献
25.
Maria Guiomar A Bahia Vicente Tadeu Lopes Buono 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(2):249-255
OBJECTIVE: The changes in fatigue resistance of nickel-titanium rotary ProFile instruments after clinical use for shaping 10 curved molar root canals were evaluated in this study. STUDY DESIGN: Twenty-five sets of files #20, #25, and #30 and tapers .04 and .06 were divided into 2 groups, one with 10 sets of new files that were tested in a fatigue test bench device as a control. The other, experimental group, with 15 sets of clinically used files, was tested in the same device. The Student t test was employed to compare mean values of the measured parameters. RESULTS: A statistically significant decrease in the number of cycles to failure was determined for the clinically used files, as compared with the new ones. The fracture point was the same for all files tested. CONCLUSIONS: The clinical use of ProFile instruments for shaping curved canals reduces their fatigue resistance. 相似文献
26.
Early during rat thymus ontogeny, an important proportion of thymocytes
expresses IL-2R and contains IL-2 mRNA. To investigate the role of the
IL-2-IL-2R complex in rat T cell maturation, we supplied either recombinant
rat IL-2 or blocking anti-CD25 mAb to rat fetal thymus organ cultures
(FTOC) under several experimental conditions. The IL-2 treatment initially
stimulated the growth of thymocytes and, as a result, induced T cell
differentiation, but the continuous addition of IL-2 to rat FTOC, as well
as the anti-CD25 administration, resulted in cell number decrease and
inhibition of thymocyte maturation. These results indicate that immature
rat thymocytes bear functional high- affinity IL-2R and that IL-2 promotes
T cell differentiation as a consequence of its capacity to stimulate cell
proliferation. Modifications in TCR alpha beta repertoire and increased
numbers of NKR- P1+ cells, largely NK cells, were also observed in
IL-2-treated FTOC. Furthermore, IL-2-responsiveness of different thymocyte
subsets changed throughout thymic ontogeny. Immature CD4-CD8-cells
responded to IL-2 in two stages, early in thymus development and around
birth, in correlation with the maturation of two distinct waves of thymic
cell progenitors. Mature CD8+ thymocytes maximally responded to IL-2 around
birth, supporting a role for IL-2 in the increased proliferation of mature
thymocytes observed in vivo in the perinatal period. Taken together, these
findings support a role for IL-2 in rat T cell development.
相似文献
27.
28.
Role of the htrA gene in Klebsiella pneumoniae virulence 总被引:3,自引:0,他引:3
We recently described the use of mini-Tn5 to generate complement-sensitive mutants derived from a complement-resistant Klebsiella pneumoniae clinical isolate deficient in the lipopolysaccharide O side chain. One mutant with a reduced capacity to survive in nonimmune human sera carried the transposon inserted in the htrA gene. We cloned and sequenced the gene and predicted from the deduced amino acid sequence that the putative HtrA homolog contains structural features similar to those of previously described HtrA proteins. To investigate the biological functions and the role of the htrA gene in the virulence of K. pneumoniae, we constructed an isogenic mutant by insertion-duplication mutagenesis. Characterization of the mutant showed that it had greater sensitivity to temperature (50 degrees C) and oxidative stress (H(2)O(2)) than the parent strain. Furthermore, the htrA mutant produced less capsule, bound more molecules of complement component C3, and was more sensitive to complement and whole-blood killing than was the parent strain. Finally, disruption of the htrA gene in a virulent K. pneumoniae strain caused a reduction of its virulence in a mice model. Our results indicate that the htrA gene plays an important role in the virulence of K. pneumoniae. 相似文献
29.
Pkd2 haploinsufficiency alters intracellular calcium regulation in vascular smooth muscle cells 总被引:7,自引:0,他引:7
Qian Q Hunter LW Li M Marin-Padilla M Prakash YS Somlo S Harris PC Torres VE Sieck GC 《Human molecular genetics》2003,12(15):1875-1880
Autosomal-dominant polycystic kidney disease is a multiorgan disease and its vascular manifestations are common and life-threatening. Despite this, little is known about their pathogenesis. Somatic mutations to the normal PKD allele in cystic epithelia and cyst development associated with the unstable Pkd2(WS25) allele suggest a two-hit model of cystogenesis. However, it is unclear if this model can account for the cardiovascular pathology or if haploinsufficiency alone is disease-associated. In the present study, we found a decreased polycystin-2 (PC2, protein encoded by Pkd2 gene) expression in Pkd2( +/-) vessels, roughly half the wild-type level, and an enhanced level of intracranial vascular abnormalities in Pkd2 (+/-) mice when induced to develop hypertension. Consistent with these observations, freshly dissociated Pkd2 (+/-) vascular smooth muscle cells have significantly altered intracellular Ca(2+) homeostasis. The resting [Ca(2+)](i) is 17.1% lower in Pkd2 (+/-) compared with wild-type cells (P=0.0003) and the total sarcoplasmic reticulum Ca(2+) store (emptied by caffeine plus thapsigargin) is decreased (P<0.0001). The store operated Ca(2+) (SOC) channel activity is also decreased in Pkd2 (+/-) cells (P=0.008). These results indicate that inactivation of just one Pkd2 allele is sufficient to significantly alter intracellular Ca(2+) homeostasis, and that PC2 is necessary to maintain normal SOC activity and the SR Ca(2+) store in VSMCs. Based on these findings, and the fact that [Ca(2+)](i) signaling is essential to the regulation of contraction, production and secretion of extracellular matrix, cellular proliferation and apoptosis, we propose that the abnormal intracellular Ca(2+) regulation associated with Pkd2 haploinsufficiency is directly related to the vascular phenotype. 相似文献
30.
J. J. Palacios J. Ferro N. Ruiz Palma S. G. Roces H. Villar J. Rodríguez P. Prendes 《European journal of clinical microbiology & infectious diseases》1998,17(11):767-772
The aim of this study was to compare the results of a commercial assay based on the ligase chain reaction [(LCR) LCx Probe System MTB; Abbott, USA] with those of culture in liquid medium (Septi-Chek AFB; Becton-Dickinson, USA) and culture on the egg-based Löwenstein-Jensen solid medium for the direct detection of Mycobacterium tuberculosis complex in nonrespiratory specimens. The results were analyzed according to the standard definition of a true-positive result. Two hundred thirty-five nonrespiratory samples routinely submitted to rule out tuberculosis were analyzed. All samples were smear-negative. Mycobacterial growth in either culture medium was detected in 18 (7.6%) specimens: Mycobacterium tuberculosis was recovered from seven (38.9%) specimens cultured on Löwenstein-Jensen medium and from 18 (100%) specimens cultured in Septi-Chek AFB. The LCR protocol was positive in 22 specimens. None of the LCR-negative controls showed positive results. All samples positive by culture on Löwenstein-Jensen medium were positive by culture in liquid medium and by the LCR assay. However, Mycobacterium tuberculosis was detected by culture in liquid medium in two specimens that were negative by the LCR assay, whereas six specimens negative by culture in liquid medium were positive by the LCR protocol; three of these were identified as true-positive results of the LCR assay. The sensitivity, specificity, and positive and negative predictive values were 33.3%, 100%, 100%, and 93.8%, respectively, for Löwenstein-Jensen medium; 85.7%, 100%, 100%, and 98.6% for the liquid medium; and 90.4%, 98.5%, 86.3%, and 99% for the LCR assay. These findings indicate that the LCR assay may be a valid method of high diagnostic yield for direct detection of Mycobacterium tuberculosis complex in nonrespiratory specimens. 相似文献