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排序方式: 共有1585条查询结果,搜索用时 15 毫秒
61.
Acar H Kaynak M Yakut T Uçar F Egeli U 《Teratogenesis, carcinogenesis, and mutagenesis》2002,22(5):369-375
We have used the single and dual color fluorescence in situ hybridization (FISH) technique combined with a new detection system, tyramide signal amplification (TSA), by using the multiple endocrine neoplasm type 1 (MEN1) gene and chromosome 11 specific alpha satellite DNA probes for the study of the allelic deletion of the MEN1 gene. The MEN1 gene is a new tumor suppressor gene and has been recently cloned on chromosome 11q13. FISH combined with the TSA detection system was performed on bone marrow interphase nuclei of 22 patients with acute myeloid leukemia (AML). The FISH-TSA analysis revealed the mono allelic deletion of the MEN1 gene in 4 out of 22 patients (18.18%), 2 of 9 AML-M2 patients (22.2%), 1 of 6 AML-M4 patients (16.6%), and 1 of 4 AML-M5 patients (25.0%). Our study indicates that allelic deletion of the MEN1 gene is not a major cause or a primary event in tumorigenesis of AML, although the long arm (q13 region) of chromosome 11 involves a chromosomal rearrangement in AML. 相似文献
62.
Hacer Akturk Murat Sutcu Ayper Somer Manolya Acar Bahar Akgun Karapınar Derya Aydin 《The journal of maternal-fetal & neonatal medicine》2016,29(21):3478-3482
Objective: To determine the incidence of vancomycin-resistant enterococcus (VRE) colonization in our neonatal intensive care unit (NICU) over five-year period, rate of progression to VRE infection and associated risk factors.Methods: A retrospective analysis of a prospective surveillance for VRE colonization and health care-associated infections was made. Contact precautions were taken against colonization, although the application varied over the years due to repairs in the unit.Results: VRE rectal colonization was detected in 200/1671 neonates (12%) admitted to NICU. It showed great interannual variability from 1.9% to 30.3%. Sytemic VRE infection developed in 6/200 VRE-colonized patients (3%) within a median of 9 days (range: 3–58 days). The risk factors for VRE infection development identified in the univariate analysis were long hospital stay (≥30 days), necrotizing enterocolitis, surgical procedure, extraventricular drainage, receipt of amphotericin B and receipt of glycopeptides after detection of VRE colonization. Crude in-hospital mortality was higher in neonates who developed a systemic VRE infection (p?<?0.001).Conclusion: Maintaining physical conditions in the unit favorable for infection control and rational use of antibiotics are essential in the control of VRE colonization and resultant infections. Special attention should be directed to VRE-colonized babies carrying the risk factors. 相似文献
63.
Odile Launay Jean-Claude Nguyen Van Annie Buu-Hoï J. F. Acar 《Clinical microbiology and infection》1997,3(5):541-544
Objective: To report a case of typhoid fever contracted in Portugal in 1994 due to a Salmonella typhi isolate which had reduced susceptibility to fluoroquinolone (MIC 1 mg/L of ciprofloxacin) and high level resistance to nalidixic acid (MIC ≥56 mg/L).
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
64.
Acar HI Comert A Ozer H Tekdemir I Loukas M Tubbs RS Elhan A 《Surgical and radiologic anatomy : SRA》2008,30(8):639-643
Arthroscopic EndoButton fixation of anterior cruciate ligament (ACL) grafts over the femoral cortex has become popular in
recent years. However, elongation of fixation materials has lead to tunnel enlargement, graft tunnel motion and instability.
Synovial fluid passages along femoral tunnels following ACL reconstruction may result in destruction of tissues. The purpose
of the present study was to identify the seating position of the EndoButton in regard to the boundaries of the knee capsule
in single-incision arthroscopic ACL reconstruction. A total of 20 cadaveric knees were dissected and arthroscopic drill guides
were used to create tibial and femoral tunnels. The distances between the exit points and boundaries of the suprapatellar
bursa at three different degrees of knee flexion were measured. The average distances from the exit points to the superior
boundaries of the suprapatellar bursa were 6.89 ± 5.40 mm (range, 16.87–1.21). However, in knee flexion of greater than 90°,
tunnel exits were placed below the superior boundaries of the suprapatellar bursa (−7.08 ± 3.69 mm, range, −3.24 to −12.87).
In order to place the EndoButton extraarticularly, a safe degree of knee flexion during femoral tunnel drilling was defined
as 80°. 相似文献
65.
Zeliha SahinNuray Acar Ozlem OzbeyIsmail Ustunel Ramazan Demir 《Acta histochemica》2011,113(3):270-276
Members of the Notch family have been detected in many developmental and cell specification processes during placental development. However, Notch protein expression in Intrauterine Growth Restriction (IUGR) and Pregnancy Induced Hypertension (PIH) is not clear. In this study we aimed to clarify the immunolocalization of Notch proteins in full-term placentas after IUGR and PIH in comparison with normal placentas. Formalin-fixed, paraffin-embedded term placentas obtained by caesarean operations were processed for immunohistochemical localization of Notch 1, 2, 4 and Jagged 2. Transmission electron microscopy was also performed. In normal term placentas, all Notch proteins were intensely immunostained in the brush border of cells of the syncytiotrophoblast layer of the basal (maternal) side and the chorionic plate (fetal) side. The endothelial cells were also intensely immunostained in both sides for Notch 1. However, in IUGR and PIH placentas, the immunoreactivities of all Notch proteins were decreased significantly in the brush border of cells of the syncytiotrophoblast layer and the reaction was generally observed in the cytoplasm of syncytiotrophoblast cells in the basal and chorionic plate sides. The reactivity in endothelial cells was also significantly decreased. Our results have shown that the immunoreactivity and localization of Notch proteins is altered in pathologic placentas. Therefore, we propose that deregulated expression of Notch proteins may contribute to the disruption of trophoblast differentiation, endothelial cell function and/or feto-maternal traffic down-regulation during pregnancy or vice versa in such pathologic conditions. 相似文献
66.
Subject-specific four-layer boundary element method (BEM) electrical forward head models for four participants, generated from magnetic resonance (MR) head images using NFT (www.sccn.ucsd.edu/wiki/NFT), were used to simulate electroencephalographic (EEG) scalp potentials at 256 recorded electrode positions produced by single current dipoles of a 3-D grid in brain space. Locations of these dipoles were then estimated using gradient descent within five template head models fit to the electrode positions. These were: a spherical model, three-layer and four-layer BEM head models based on the Montreal Neurological Institute (MNI) template head image, and these BEM models warped to the recorded electrode positions. Smallest localization errors (4.1–6.2 mm, medians) were obtained using the electrode-position warped four-layer BEM models, with largest localization errors (~20 mm) for most basal brain locations. When we increased the brain-to-skull conductivity ratio assumed in the template model scalp projections from the simulated value (25:1) to a higher value (80:1) used in earlier studies, the estimated dipole locations moved outwards (12.4 mm, median). We also investigated the effects of errors in co-registering the electrode positions, of reducing electrode counts, and of adding a fifth, isotropic white matter layer to one individual head model. Results show that when individual subject MR head images are not available to construct subject-specific head models, accurate EEG source localization should employ a four- or five-layer BEM template head model incorporating an accurate skull conductivity estimate and warped to 64 or more accurately 3-D measured and co-registered electrode positions. 相似文献
67.
Maunoury C Acar P Sidi D 《European journal of nuclear medicine and molecular imaging》2003,30(12):1651-1656
Iodine-123 metaiodobenzylguanidine (MIBG) cardiac scintigraphy is a useful tool for the assessment of cardiac adrenergic neuronal function, which is impaired in children with idiopathic dilated cardiomyopathy (DCM). In adults with DCM, long-term treatment with carvedilol improves both cardiac adrenergic neuronal function and left ventricular function. The aim of this prospective study was to evaluate the impact of carvedilol on cardiac adrenergic neuronal function using 123I-MIBG scintigraphy and on left ventricular function using equilibrium radionuclide angiography in children with DCM. Seventeen patients (11 female, six male; mean age 39±57 months, range 1–168 months) with DCM and left ventricular dysfunction underwent 123I-MIBG cardiac scintigraphy and equilibrium radionuclide angiography before and after a 6-month period of carvedilol therapy. A static anterior view of the chest was acquired 4 h after intravenous injection of 20–75 MBq of 123I-MIBG. Cardiac neuronal uptake of 123I-MIBG was measured using the heart to mediastinum count ratio (HMR). Radionuclide left ventricular ejection fraction (LVEF) was assessed following a standard protocol. MIBG cardiac uptake and left ventricular function respectively increased by 38% and 65% after 6 months of treatment with carvedilol (HMR=223%±49% vs 162%±26%, P<0.0001, and LVEF=43%±17% vs 26%±11%, P<0.0001). Carvedilol can improve cardiac adrenergic neuronal and left ventricular function in children with dilated cardiomyopathy. Further studies are needed to assess the relationship between improvement in MIBG cardiac uptake and the beneficial effects of carvedilol on morbidity and mortality. 相似文献
68.
J R Seguin P Bouillon P Aubry J Acar J P Cachera 《The Thoracic and cardiovascular surgeon》1984,32(6):386-388
A case of a traumatic aorto-right ventricular fistula associated with an aortic valve injury and subsequent successful treatment is reported. A possible delay in diagnosis necessitates follow-up of patients after penetrating thoracic wounds. Early surgical treatment is mandatory because of the risks of both heart failure and endocarditis and because of the low operative morbidity. An aortic approach appears to be preferable because it permits repair of both the fistula and the valvular injury. Reconstruction of valvular injuries is preferable since long-term competence without prosthetic replacement can be achieved. 相似文献
69.
J Acar A Vahanian M Passeleau D Gabay P Vernant P Corone F Guérin 《Archives des maladies du coeur et des vaisseaux》1984,77(4):397-404
The aim of this cooperative study was to analyse the clinical profile of subvalvular aortic stenosis (SVAS) in adults. Thirty one cases were collected : patients aged 17 to 60 years (average 34 years). The diagnosis was confirmed in all patients either at surgery (30 cases) or at autopsy (1 case). The overall incidence of SVAS in patients with fixed obstruction to left ventricular ejection operated in the same period was 3.5%. Associated congenital malformations were detected in 15% of cases but intracardiac shunts were rare. Adult SVAS is a purer malformation than in children, probably because of spontaneous and surgical selection. The anatomical type of stenosing lesion in this series was a subaortic ring or membrane; 45% of patients, usually over 40 years of age (7 out of 9) had localised septal hypertrophy at the level of the diaphragmatic obstruction. The clinical presentation was that of mixed aortic disease with associated stenosis and regurgitation. Over 80% of patients had aortic incompetence diagnosed clinically (26 out of 31 cases) or on aortography (24 out of 25 cases); the regurgitant flow was assessed as mild in 15 cases, moderate in 6 cases and severe in 3 cases. There were obvious valvular lesions at surgery in 19 cases, especially in patients over 40 years of age (8 out of 9 cases). The mechanism was variable : non-specific (8 cases), destructive (6 cases), rheumatic (2 cases) or congenital (3 cases). Bacterial endocarditis was particularly common (26% of cases). Adult SVAS is a particularly difficult clinical diagnosis : the electrocardiogram and chest X-ray are not very informative.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
70.
Summary Forty-one patients with either complicated or uncomplicated urinary tract infections were treated with co-trimazine tablets (410 mg sulphadiazine, 90 mg trimethoprim). Ten were given one tablet once daily, ten were given two tablets once daily and 21 were given one tablet twice daily. 88% were cured. The results were independent of the dosage interval, but depended on the type of infection. Eight patients suffered a reinfection. Two of the sevenE. coli strains isolated were resistant to sulphadiazine and one was resistant to sulphadiazine and trimethoprim. TwoCitrobacter freundii strains were resistant to sulphadiazine and trimethoprim. There was a relapse in five cases in which all isolates were sensitive to sulphadiazine and trimethoprim. There were no subjective side-effects. Eosinophilia was observed in two patients and transitory leucopenia in another two. One case of eosinophilia and one case of transitory leucopenia could possibly be related to the medication.
Untersuchung zur Wirksamkeit und Verträglichkeit von Co-trimazin bei Harnwegsinfektionen in ein- oder zweimal täglicher Verabreichung
Zusammenfassung Einundvierzig Patienten mit sowohl unkomplizierten als auch komplizierten Harnwegsinfektionen wurden mit Co-trimazin Tabletten (410 mg Sulphadiazin, 90 mg Trimethoprim) behandelt, und zwar zehn mit einer, zehn mit zwei Tabletten einmal täglich und 21 mit einer Tablette zweimal täglich. Die Heilungsrate betrug insgesamt 88%. Das Ergebnis war unabhängig vom Dosierungsintervall, hing aber von der Art der Infektion ab. Bei acht Patienten kam es zur Reinfektion, zwei der sieben isoliertenE. coli Stämme waren resistent gegen Sulphadiazin, einer resistent gegen Sulphadiazin und Trimethoprim. ZweiCitrobacter freundii Stämme waren resistent gegen Sulphadiazin und Trimethoprim. Bei fünf Fällen trat ein Rezidiv mit demselben Stamm auf, alle Isolate waren gegenüber Sulphadiazin und Trimethoprim empfindlich. Subjektive Nebenwirkungen traten nicht auf; in je zwei Fällen wurde eine Eosinophilie und eine passagere Leukopenie beobachtet, von denen je eine mit der Medikation in Zusammenhang stehen könnte.相似文献