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991.
Filho OG Gordan AN Mello Rde A Neto CS Heinke T 《International journal of surgical pathology》2004,12(2):151-153
Hamartomas were first described by Albrecht in 1904, who defined them as tumor-like malformations in which there was abnormal blending of the normal components of an organ. The myoid hamartoma is a rare benign lesion of the breast and has an uncertain origin, possibly in the walls of the blood vessels, muscularis mammillae of the areolae, and mainly in myoepithelium. We report 3 cases of myoid hamartomas of the breast, with the clinical, radiologic, and histopathological findings, and review the literature. The 3 lesions showed normal breast ducts and lobules, entrapped by a muscular stroma and some foci of mature adipose tissue. The muscular origin of part of the stroma was confirmed by strong reactiveness with smooth-muscle actin. 相似文献
992.
Somatic mosaicism for a MECP2 mutation associated with classic Rett syndrome in a boy 总被引:4,自引:0,他引:4
Topçu M Akyerli C Sayi A Törüner GA Koçoğlu SR Cimbiş M Ozçelik T 《European journal of human genetics : EJHG》2002,10(1):77-81
Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism. 相似文献
993.
Gil LH Alves FP Zieler H Salcedo JM Durlacher RR Cunha RP Tada MS Camargo LM Camargo EP Pereira-da-Silva LH 《Journal of medical entomology》2003,40(5):636-641
Studies on seasonal anopheline fauna variation were performed in two distinct settlements in the State of Rond?nia, Brazil: one at the Madeira River banks (Portuchuelo) with stable native Amazonian population; the other at an inland lumber-extracting farm (Urupá) in dry land, in which adults are mostly migrants. During a 6-yr period (1994-2000), 8,638 adult anophelines were collected: 2,684 in Urupá and 5,954 in Portuchuelo. Anopheles darlingi represented >95% of total mosquitoes caught. Dissection of 4,424 A. darlingi females yielded a very low sporozoite infection index below 0.1%. Oocysts were found in both localities in approximately 0.1% of dissected mosquitoes. Determination of the hour biting rates disclosed seasonal variations in both localities. However, in Portuchuelo, mosquito density peaked at the acme of the rainy season, whereas at Urupá it peaked in the dry season. The increase in mosquito density and incidence of malaria cases were coincident. The high mosquito densities observed in the riverine settlement of Portochuelo sector B, which permits evaluation in > 10,000 mosquitoes' bites/person/year, could explain, in spite of the low mosquito's infection index, the previously described development of natural immunity in the local population that is not observed in the dry land agroindustrial settlement of Urupá. 相似文献
994.
Adamcová M Sterba M Klimtová I Simůnek T Hrdina R Gersl V Ponka P 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2003,46(4):171-174
Both cardiac troponin T (cTnT) and cardiac troponin I (cTnI) are considered to be reliable biomarkers with sufficient sensitivity and specificity for cardiac injury in the majority of laboratory animals. The aim of our study was to compare the diagnostic performance of cTnT and cTnI in three groups of rabbits: 1) control (saline 1 ml/kg i.v.); 2) Salicylaldehyde Isonicotinoyl Hydrazone--SIH (50 mg/kg, once weekly, i.p.; partially dissolved in 10% Cremophor solution); 3) 10% Cremophor solution in water (2 ml/kg i.v.). The drugs were given once a week, 10 administrations. The concentration of cTnT was measured using Elecsys Troponin T STAT Immunoassay (Roche). The concentration of cTnI was measured using AxSYM Troponin I (Abbott). The linear regression model was applied to see if there is a dependence between cTnT and cTnI. The coefficient of determination was not acceptable in all groups. The highest value of R2 was found in the control group (R2 = 0.424). We may conclude that in rabbits meaningful dependence between cTnT and cTnI was not found. According to our long-term experiences cTnT seems to be more suitable cardiomarker in rabbits in comparison with cTnI where the data are characterized by the large scatter. 相似文献
995.
Itziar Benito-Sánchez Melissa M. Ertl Rosario Ferrer-Cascales Javier Oltra-Cucarella Joaquín A. Ibáñez-Alfonso Mahia Saracostti Schwartzman 《Developmental neuropsychology》2020,45(4):189-199
ABSTRACT To determine the prevalence of low scores on two neuropsychological tests commonly used to evaluate learning and memory in children. 6,030 healthy children from 10 countries in Latin America and Spain were administered Rey–Osterrieth Complex Figure (ROCF) and the Test de Aprendizaje y Memoria Verbal–Infantil (TAMV-I). Results showed that low scores are common when multiple neuropsychological outcomes (tests and/or scores) are evaluated in healthy individuals. Clinicians should consider the higher probability of low scores in a given individual when evaluating learning and memory using various sets of scores to reduce false-positive diagnoses of cognitive deficits in pediatric populations. 相似文献
996.
H. G. Lasch F. Rodríguez-Erdmann Kl. Schimpf 《Journal of molecular medicine (Berlin, Germany)》1961,39(12):645-647
Zusammenfassung Beim Sanarelli-Shwartzman-Phänomen nehmen mit der Verlängerung der Gerinnungszeit und dem Abfall der Faktoren des Prothrombinkomplexes die Aktivität der Anti-Blutthrombokinase zu und diejenige des Anti-Thrombins III ab. Das entspricht dem Verhalten dieser beiden physiologischen Hemmstoffe während der Gerinnung von Blut in vitro. Der Befund stützt unsere Auffassung, daß ein auf noch unbekanntem Wege ausgelöster intravasaler Gerinnungsmechanismus zu Fibrinthromben in der Strombahn und zum sekundären Verbrauch einzelner Gerinnungsfaktoren führt. 相似文献
997.
Mary C. Kuhns Anne L. McNamara Robert P. Perrillo Carlos M. Cabal Carolyn R. Campbell 《Journal of medical virology》1989,27(4):274-281
Serological markers of hepatitis B virus (HBV) replication were assessed in a randomized, controlled trial of prednisone withdrawal followed by α -interferon in the treatment of chronic hepatitis B. HBV DNA levels in more than 700 serial serum samples from 41 patients were determined by a sensitive and quantitative solution hybridization assay. Results were compared with HBV DNA polymerase (DNAp) activity and hepatitis B e antigen (HBeAg) in 21 untreated controls and 20 treated patients. Among treated patients, the mean pretherapy HBV DNA values were higher in nonresponders than in responders. During prednisone treatment, DNA levels increased an average of 2.1-fold in responders and 1.4-fold in nonresponders. During the 2-week rest interval between prednisone and interferon, DNA values fell an average of 57% in responders. In contrast, the mean DNA values in nonresponders did not change during the same interval. This early distinction between responders and nonresponders was not apparent from DNAp or HBeAg results. During interferon treatment, HBV DNA became undetectable in responders and remained negative during a 1-year follow-up. DNA in nonresponders declined to 14% of baseline during interferon treatment but increased to pretherapy levels after treatment. DNAp values generally paralleled HBV DNA values, but DNAp activity showed more variability and lower sensitivity than did the hybridization assay results. HBeAg values varied independently of HBV DNA and DNAp with a much delayed decline in responders. These results indicate that HBV DNA, when measured quantitatively by a sensitive solution hybridization assay, is an early predictor of the effects of antiviral agents on replication. 相似文献
998.
Jaros E Príborský J Klein L 《Acta medica (Hradec Králové). Supplementum Universitas Carolina, Facultas Medica Hradec Králové》1999,42(2):61-63
Keloid and hypertrophic scars are relatively frequent not wanted consequences of surgical treatment. 145 patients with unsatisfactory skin healing were treated in our department during last 5 years. When compared with corticotherapy and laser-therapy kryotherapy is very effective method. There were outstanding results with combination of cryotherapy and corticotherapy. 相似文献
999.
Stochastic resonance in human electroencephalographic activity elicited by mechanical tactile stimuli 总被引:1,自引:0,他引:1
Stochastic resonance (SR) is a phenomenon in which the response of a non-linear system to a weak input signal is optimized by the presence of noise. The aim of this study was to demonstrate the experimental occurrence of SR in electroencephalographic (EEG) activity elicited by mechanical tactile stimuli. Our experiments show that EEG responses evoked by mechanical tactile stimuli in the region overlying the somatosensory cortical area were optimized by the addition of certain noise amplitudes. All subjects showed distinct SR behavior. The signal-to-noise ratio (SNR) of the response evoked by mechanical indentations of the skin was an inverted U-like function of the input noise. As the noise amplitude increased, SNR values became larger. A maximum value was reached with a particular noise amplitude value. Beyond such peak, with higher noise amplitudes, the curve subsided gradually. To our knowledge, this is the first documented evidence that such remarkable phenomenon embodies electrical processes of the human brain. Such behavior might explain related findings described in psychophysical studies. 相似文献
1000.
Badalová J Svobodová M Havelková H Vladimirov V Vojtísková J Engová J Pilcík T Volf P Demant P Lipoldová M 《Genes and immunity》2002,3(4):187-195
The strain BALB/cHeA (BALB/c) is a high producer, and STS/A (STS) a low producer of IgE after Leishmania major infection. We analyzed this strain difference using 20 recombinant congenic (RC) BALB/c-c-STS/Dem (CcS/Dem) strains that carry different random subsets of 12.5% of genes of the strain STS on the BALB/c background. Strains CcS-16 and -20 exhibit a high and a low IgE level, respectively. In their F(2) hybrids with BALB/c we mapped nine Leishmania major response (Lmr) loci. Two of them we previously found to influence IgE level in CcS-5. IgE production in CcS-16 is controlled by loci on chromosomes 2, 10, 16 and 18 and in CcS-20 by loci on chromosomes 1, 3, 4, 5 and 8. The STS alleles of loci on chromosomes 1, 4, 5, 8 and 10 were associated with a low, whereas the STS alleles on chromosomes 16 and 18 with a high IgE production. The loci on chromosomes 2 and 3 have no apparent individual effect, but interact with the loci on chromosomes 10 and 1, respectively. The loci on chromosomes 10 and 18 were mapped in the regions homologous with the human regions containing genes that control total serum IgE and intensity of infection by Schistosoma mansoni, suggesting that some Lmr loci may participate in the pathways influencing atopic reactions and responses to several parasites. The definition of genes controlling anti-parasite responses will permit a better understanding of pathways and genetic diversity underlying the disease phenotypes. 相似文献