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991.
Poliovirus infection of either undifferentiated or differentiated U937 cells produced a decrease in the percentage of cells positive for the surface expression of the CD4, CD11c, CD14, or 8E11 antigens. The number of 4F2 surface molecules per cell increased in infected normal U937 cells, but was unaffected in differentiated cells. The level of O2- production in infected differentiated U937 cells was approximately 50% of that found when not infected. Finally, poliovirus RNA levels and infectious particle production were similar in either cell type. 相似文献
992.
Ten normal children (mean age = 9 years) and 12 dyslexic children (mean age = 8.1 years) were compared for latency, amplitude and topographic distribution of both parameters of P300. We found a significant increase in P300 latency in the dyslexic group. Noteworthy is the increase in amplitude in the central parietal area in the control group. These facts and their incidence are discussed in the present study. 相似文献
993.
J I García Alonso A López García J Pérez Parajón E Blanco González A Sanz Medel J B Cannata 《Clinica chimica acta; international journal of clinical chemistry》1990,189(1):69-79
Ion-exchange high performance liquid chromatography of serum proteins was combined with aluminium determination by electrothermal-atomisation-atomic-absorption spectroscopy and fluorimetry for studying the distribution of aluminium in human serum in the absence and in the presence of desferrioxamine. Aluminium was eluted as a single peak in the same fraction as transferrin. However, following the addition of desferrioxamine most of the aluminium was liberated from transferrin and become attached to the chelator. 相似文献
994.
Bettina Hause Frank Baldauf Kerstin Stock Claus Wasternack Michael Metzlaff 《Current genetics》1986,10(10):785-790
Summary Mitochondrial DNA (mtDNA) from Lycopersicon esculentum was purified from cell suspension cultures. The DNA, isolated from mitochondria purified by two successive sucrose density gradients, was uncontaminated with nuclear DNA or DNA from proplastids. The total molecular weights of BamHI, BglI, and BglII fragments indicate a mitochondrial genome size of at least 270 kb. Cross hybridization between tomato mtDNA and cloned spinach plastid genes revealed some homology. In hybridization experiments using cloned mitochondrial rRNA genes and BamHI digested total mtDNA the presence of recombination repeats is demonstrated. 相似文献
995.
Germán Juan Rijo Ana Alonso García Ángeles de la Rua Calderón Paz Pérez Payo Mercedes Canteli Castahon Pedro Prada Gómez Ramón Alonso Pantiga Asunción Querejeta Recalde Luis Olay Gayoso Reinerio Rodríguez 《Clinical & translational oncology》2002,4(6):314-321
We assessed the role of the radiation therapy as the exclusive treatment of the epithelial tumours of the pinna, evaluating the control disease, the rate of late complications and the cosmetic results. One hundred and four patients with epidermoid carcinoma of the pinna and radical treatment with radiotherapy were analyzed retrospectively. 53 (51%) were squamous cell carcinoma and 51 (49%) basocelular carcinoma. Classification according to tumours size was as follows: ≤1 cm, 22 (21.2%); 1–2 cm, 47 (45.2%); 2–3 cm, 19 (18.3%), and >3 cm, 11 (10.6%). Eighty eight patients (84.6%) were treated with60Co, 15 (14.4%) with ortovoltage and one patient with 9 MeV electron. The median follow up is 55 month (14–257). The local control, complication like condritis, condronecrosis and audition damage, and the cosmetic result were the factors analyzed. The 5 and 10 years actuarial local control rate is 89.8% and 87.6%, respectively. In an univariate analysis including variables like size, localization, histologic type, differentiation grade, energy type, irradiation technique, doses and response to treatment, the bad prognostic factors regarding to local control, were found to be the size (>3 cm) (p=0.013), localization (posterior sulcus) (p=0.012) and response to treatment (not complete) (p=0.046). In a multivariate analysis only the size showed this tendency (p=0.05). After the intent of rescue in the 11 patients that failed locally, the final local control rate was 95.19% (99/104). Four patients with squamous cell carcinoma had nodal regional recurrence, which didn't occur in the patients with basocelular carcinoma. Eight (7.7%) patients presented some degree of condritis, which was resolved medically in all the cases except one patient that evolved to condronecrosis. The cosmetic results in the 76 patients evaluated was excellent in 53 (69.7%) and acceptable in 12 (22.6%). Radiotherapy is recommended for treatment of the epithelial tumour of the pinna, mainly in tumors less than 3 cm, getting local control rate similar to surgery but avoiding its cosmetic and functional sequelae. 相似文献
996.
997.
Bettina Jørgensen Kristian Karstoft Troels Munch Jørgensen Søren Rittig Jørgen Frøkiær Michael Pedersen 《Zeitschrift für medizinische Physik》2010,20(2):115-121
PurposeThis MRI study demonstrates our first clinical experiences with structural and functional evaluation in children with renal dysfunction, and communicates our experience with quantitative measurements of renal function compared to reference values found employing radionucleotides.Material and methodsWe included renal impaired children who were recruited for clinical radioisotopic GFR measurements (n=8). MRI was performed 2 hours after Cr-EDTA measurements and was conducted using a protocol involving both anatomical/structural sequences and a dynamic contrast-enhanced sequence. Data obtained with the dynamic MRI sequence were processed using the graphical Patlak approach to obtain estimates of GFR.ResultsWe were able to characterize the intrarenal configuration (cortex, medulla, pelvicalyceal arrangement) in all cases. Functional analyses of dynamic contrast-enhanced MRI revealed an overall underestimation of GFR measured by MRI compared to Cr-EDTPA measures (range: ?2% to ?43%).ConclusionsWe advocate the use of MRI as a single-modality approach in the structural and functional evaluation of impaired kidneys in children, and concurrently, we presented a clinically available strategy for estimations of renal cortical volume and single kidney function. However, the use of MRI contrast agents have recently become controversial in renal patients due to the risk of NSF. 相似文献
998.
Pablo Sáenz López Fernando Vázquez Alonso José M. Romero Rafael Carretero Miguel Tallada Buñuel Francisco Ruiz Cabello José Manuel Cózar Olmo 《Actas urologicas espa?olas》2009,33(5):474-481
Inflammation has been implicated as an etiological factor in different human cancers. Allelic variations in the genes implicated in inflammation are candidates as genetic determinants or markers of renal carcinoma risk. The present study investigates whether polymorphisms of the genes that give rise to increases in the levels of proinflammatory cytokines and chemokines are associated with an increased risk of renal carcinoma. To this effect, a number of case-control studies were designed to assess the correlation between renal carcinoma and polymorphisms il10-1082 a/g (rs 1800896), il10-592 a/c (rs 1800872), il10-819 c/t (rs 1800871), il10-1082 a/g, il4-590 c/t (rs 2243250), tnf-a-308 a/g (rs 1800629), rantes-403 g/a (rs 2107538), il1-a-889 c/t (rs 1800587), mcp-1 2518 g/a (rs 1024611), ctla-4/+49 a/g (rs 231775) and ctla-4 ct60 a/g (rs 3087243) in 127 renal carcinoma patients and in 176 healthy subjects.The results obtained in relation to cytokine polymorphism il-10-1082 a/g indicate that ag heterozygosity status is the principal risk factor in relation to locally advanced or metastatic tumor stage and renal carcinoma. in the case of the molecule ctla4, the results obtained in renal cancer reveal an association between the polymorphisms of the ctla-4 gene and an increased risk of developing renal cell carcinoma. a high genotypic frequency of polymorphisms ctla4/ct60-aa and ctla4/a49g-aa is observed in patients with renal cell carcinoma versus the controls. an association has been established between polymorphism ctla4/ct60 and tumor grade in patients with renal cell carcinoma. logistic regression analysis has confirmed these data, demonstrating a high frequency of the aa genotype in patients with high-grade tumors.The results obtained support the hypothesis that different genetic factors implicated in the regulation of adaptive immune responses, stromal cell composition and local cytokine production levels may be crucial elements in the modification of the clinicopathological parameters of renal carcinoma. 相似文献
999.
Cristina M. Ramírez Miriam Gonzlez Mario Díaz Rafael Alonso Isidre Ferrer Gabriel Santpere Berta Puig Gundela Meyer Raquel Marin 《Molecular and cellular neurosciences》2009,42(3):172-183
Voltage-dependent anion channel (VDAC) is a mitochondrial porin also found in the neuronal membrane (pl-VDAC), where its function may be related to redox homeostasis and apoptosis. Murine models have evidenced pl-VDAC into caveolae in a complex with estrogen receptor alpha (mERα), which participates in neuroprotection against amyloid beta (Aβ), and whose integration into this hydrophobic domain remains unclear. Here, we have demonstrated in caveolae of human cortex and hippocampus the presence of pl-VDAC and mERα, in a complex with scaffolding caveolin-1 which likely provides mERα stability at the plasma membrane. In Alzheimer's disease (AD) brains, VDAC was accumulated in caveolae, and it was observed in dystrophic neurites of senile plaques, whereas ERα was expressed in astrocytes surrounding the plaques. Together with previous data in murine neurons demonstrating the participation of pl-VDAC in Aβ-induced neurotoxicity, these data suggest that the channel may be involved in membrane dysfunctioning observed in AD neuropathology. 相似文献
1000.
Bernhard J. Steinhoff Michael A. Ueberall Hartmut Siemes Gerd Kurlemann Bettina Schmitz Lars Bergmann The LAM-SAFE Study Group 《Seizure》2005,14(8):432-605
OBJECTIVE: To investigate efficacy and safety of lamotrigine (LTG) versus carbamazepine (CBZ) or valproic acid (VPA) in newly diagnosed focal (FE) and idiopathic generalised (GE) epilepsies in adolescents and adults. METHODS: Open-label randomised comparative multicentre 24-week monotherapy trial in newly diagnosed epilepsy patients of >or=12 years of age. Patients with FE were treated with LTG or CBZ, those with GE received LTG or VPA. The primary efficacy variable was the number of seizure-free patients during study weeks 17 and 24. RESULTS: Two hundred and thirty-nine patients were included. One hundred and seventy-six patients suffered from FE and 63 from GE. In the FE group, 88 patients each were treated with CBZ or LTG. Ninety-four percent of the CBZ patients and 89% of the LTG patients became seizure-free according to an intent-to-treat analysis (not statistically different). The rate of patients discontinuing treatment due to adverse events or a lack of efficacy was 19% with CBZ compared to 9% with LTG (not statistically different). In the GE group, 30 patients received VPA and 33 LTG. During study weeks 17 and 24, 61% of the LTG patients and 84% of the VPA patients had become seizure-free (not statistically significant). The drop-out rate due to lack of efficacy or adverse events was 12% with LTG and 3% with VPA (not statistically different). CONCLUSIONS: This study indicates that the effectiveness of LTG in focal and generalised epilepsy syndromes as initial monotherapy in patients >or=12 years is in the range of standard first-line antiepileptic drugs. 相似文献