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991.
Stefanie Abel Katharina Dressel Ruth Bitzer Dorothee Kümmerer Irina Mader Cornelius Weiller Walter Huber 《NeuroImage》2009,44(3):1113-1124
In picture–word interference paradigms, the picture naming process is influenced by an additional presentation of linguistic distractors. Naming response times (RTs) are speeded (facilitation) by associatively-related and phonologically-related words when compared to unrelated words, while they are slowed down by categorically-related words (inhibition), given that distractor onsets occur at appropriate stimulus onset asynchronies (SOAs). In the present study with healthy subjects, we for the first time integrated all four auditorily presented distractor types into a single paradigm at an SOA of ? 200 ms, in order to directly compare behavioral and neural interference effects between them. The behavioral study corroborated results of previous studies and revealed that associatively-related distractors speeded RTs even more than phonologically-related distractors, thereby becoming equally fast as naming without distractors. Distractors were assumed to specifically enhance activation of brain areas corresponding to processing stages as determined in a cognitive model of word production (Indefrey, P., Levelt, W.J.M., 2004. The spatial and temporal signatures of word production components. Cognition 92, 101–144.). Functional magnetic resonance imaging (fMRI) at 3 T revealed activation of left superior temporal gyrus exclusively for phonologically-related distractors, and activation of left or right lingual gyrus exclusively for associatively-related and categorically-related distractors, respectively. Moreover, phonologically-related distractors elicited phonological–phonetic networks, and both semantic distractors evoked areas associated with mental imagery, semantics, and episodic memory retrieval and associations. While processes involved in distractor inhibition (e.g., conflict/competition monitoring) and high articulatory demands were observed for categorically-related distractors, priming of articulatory planning was revealed for associatively-related distractors. We conclude that activations of neural networks as obtained by the fMRI interference paradigm can be predicted from a cognitive model. 相似文献
992.
Assia L Angelova Marc Aprahamian Ginette Balboni Henri-Jacques Delecluse Regina Feederle Irina Kiprianova Svitlana P Grekova Angel S Galabov Mathias Witzens-Harig Anthony D Ho Jean Rommelaere Zahari Raykov 《Molecular therapy》2009,17(7):1164-1172
The incidence of lymphomas developing in both immunocompetent and immunosuppressed patients continues to steadily increase worldwide. Current chemotherapy and immunotherapy approaches have several limitations, such as severe side toxicity and selection of resistant cell variants. Autonomous parvoviruses (PVs), in particular the rat parvovirus H-1PV, have emerged as promising anticancer agents. Although it is apathogenic in humans, H-1PV has been shown to infect and suppress various rat and human tumors in animal models. In this study, we demonstrate the capacity of H-1PV for efficiently killing, through necrosis, cell cultures originating from Burkitt''s lymphoma (BL), while sparing normal B lymphocytes. The cytotoxic effect was generally accompanied by a productive H-1PV infection. Remarkably, parvovirus-based monotherapy efficiently suppressed established BL at an advanced stage in a severe combined immunodeficient (SCID) mouse model of the disease. The data show for the first time that an oncolytic parvovirus deserves further consideration as a potential tool for the treatment of some non-Hodgkin B-cell lymphomas, including those resistant to apoptosis induction by rituximab. 相似文献
993.
994.
The Immunosuppressive Properties of the HIV Vpr Protein Are Linked to a Single Highly Conserved Residue, R90
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995.
Grill S Banzola I Li Y Rekhviashvili T Legler TJ Müller SP Zhong XY Hahn S Holzgreve W 《Archives of gynecology and obstetrics》2009,279(4):533-537
Purpose To examine the potential high throughput capability and efficiency of an automated DNA extraction system in combination with
mass spectrometry for the non-invasive determination of the foetal Rhesus D status.
Methods A total of 178 maternal plasma samples from RHD-negative pregnant women were examined, from which DNA was extracted using the automated Roche MagNA Pure™ system. Presence
of the foetal RHD gene was detected by PCR for RHD exon 7 and subsequent analysis using the Sequenom MassArray™ mass spectrometric system.
Results We determined that as little as 15 pg of RHD-positive genomic DNA could be detected in a background of 585 pg of RHD-negative genomic DNA. The analysis of the clinical samples yielded a sensitivity and specificity of 96.1 and 96.1%, respectively.
Conclusion Our study indicated that automated DNA extraction in combination with mass spectrometry permits the determination of foetal
Rhesus D genotype with an accuracy comparable to the current approaches using real-time PCR. 相似文献
996.
Pollard I 《Seminars in Fetal & Neonatal Medicine》2007,12(2):106-113
Epidemiological evidence suggests that an adverse prenatal environment can have profound long-term health consequences throughout postnatal life. This chapter discusses the underlying mechanisms implicated in the consumption of mood-altering recreational drugs and teratogenicity in the fetus. The way metabolic parameters in pregnancy influence the pharmacokinetic characteristics of drugs and alcohol and the developmental stage of neurotoxicity are reviewed. The general underlying mechanisms that link multifaceted interactions between drug characteristics, gene polymorphisms, dietary deficiencies, changed endocrine indices and fetal programming are outlined, with specific examples throughout the text. As developmental injury is of significant social concern, the final section questions whether society provides adequate support for making appropriate and informed lifestyle choices to alleviate preventable transgenerational harm. 相似文献
997.
998.
de Vries MC Rodenburg RJ Morava E van Kaauwen EP ter Laak H Mullaart RA Snoeck IN van Hasselt PM Harding P van den Heuvel LP Smeitink JA 《European journal of pediatrics》2007,166(3):229-234
Failure to thrive, feeding difficulties, variable forms of infantile epilepsy or psychomotor developmental delay and hypotonia
were the most frequent clinical disease presentations in eight children with combined oxidative phosphorylation enzyme complex
deficiencies carrying mutations in the polymerase gamma (POLG1) gene. Five out of eight patients developed severe liver dysfunction during the course of the disease. Three of these patients
fulfilled the disease criteria for Alpers syndrome. Most children showed deficiencies of respiratory chain enzyme complexes
I and III, in combination with complex II, complex IV and/or PDHc in muscle, whereas in fibroblasts normal enzyme activities
were measured. All children carried homozygous or compound heterozygous mutations in the POLG1 gene, including two novel mutations in association with mtDNA depletion. Conclusion We suggest performing POLG1 mutation analysis in children with combined oxidative phosphorylation deficiencies in muscle, even if the clinical picture
is not Alpers syndrome. 相似文献
999.
Nutman A Postovsky S Zaidman I Elhasid R Vlodavsky E Kreiss Y Ben Arush MW 《Pediatric hematology and oncology》2007,24(1):53-61
The authors describe the case of a 19-year-old female patient with a primary primitive neuroectodermal tumor (PNET) of the thoraco-lumbar spinal cord, who presented with acute urinary retention and back pain for 2 months. Magnetic resonance imaging revealed an intradural extramedullary tumor, 6.5 cm long, in the region of the conus medullaris. Histological examination disclosed a small round cell tumor with immunohistochemical characteristics of a peripheral PNET. Metastatic workup showed no evidence of an intracranial tumor or metastases outside the neuroaxis. The patient received multidisciplinary treatment, including surgical excision, irradiation of the entire cranio-spinal axis, and high-dose chemotherapy with autologous stem cell rescue. Presently, 24 months after diagnosis, the patient remains in complete remission. 相似文献
1000.
Caliskan M Gatti G Sosnovskikh I Rotmensz N Botteri E Musmeci S Rosali dos Santos G Viale G Luini A 《Breast cancer research and treatment》2008,112(3):513-521
Background Paget’s disease of the breast is an uncommon presentation of breast malignancy, accounting for 1–3% of all the breast tumors
and presents in different histopathologic patterns: in association with an underlying invasive or non invasive carcinoma,
or without any underlying neoplasia. In the literature, different methods are used for the treatment. Mastectomy with or without
axillary dissection has been considered as the standard treatment procedure for many years. Several studies have already shown
that breast conservation with radiation therapy is an oncologically safe option. Regarding the axillary approach, several
studies have documented the presence of positive sentinel lymph node even in Paget’s disease alone. The objective of this
study was to retrospectively analyze outcome of patients affected by Paget’s breast disease and to define our institutional
experience. Patients and methods Between May 1996 and February 2003, 114 patients with confirmed Paget’s disease of the breast were retrieved and underwent
surgery at the European Institute of Oncology of Milan, Italy. The median age of the patients was 54 years at the time of
the diagnosis. In our study, the histopathological examination of the operated specimen revealed one hundred seven patients
with Paget’s disease associated with an underlying invasive or non invasive carcinoma, and seven patients without underlying
carcinoma. Patients underwent either conservative breast surgery or mastectomy, with or without sentinel lymph node biopsy
and/or axillary surgery. Each patient was evaluated after surgery at a multidisciplinary meeting to selecting systemic therapy.
Results Seven patients had “pure” Paget’s disease of the breast and one hundred seven had the disease associated with an underlying
carcinoma. As surgical techniques 71 mastectomies and 43 breast conserving surgeries have been performed. Complete axillary
dissection was done in patients with clinically positive lymph node and/or sentinel lymph node biopsy positive. Sentinel lymph
node biopsy was performed in nineteen patients with invasive component and five were positive and underwent axillary dissection.
Eleven sentinel lymph node biopsies were done in patients with non invasive component and none of them was positive. Adjuvant
systemic therapies were based on the final tumor, node and metastasis stage: thirty patients received adjuvant chemotherapy
alone, fourteen received endocrine treatment alone, twenty-six patients were evaluated to receive both chemo and endocrine
therapy. The median duration of follow up was 73 months and was updated in the last 6 months. Five patients developed local
recurrence, one had regional recurrence, another two had loco-regional recurrences and fourteen had distant metastasis as
a first event. Malignancy-related deaths were censored in the statistical analyses cancer for and due to another tumor in
eleven patients. Additionally, deaths were not related to malignancy totally in thirteen patients. Conclusions Screening examination and imaging techniques are fundamental. Breast conserving surgery combined with breast irradiation
for patients with invasive and non invasive breast carcinoma has become the treatment of first choice. All surgical conservative
approaches should include the complete nipple–areolar complex and margins of resected specimen free of tumor. Thanks to the
evolution of the conservative approach, good cosmetic result can be obtained. To be informed about the axillary lymph node
status and to avoid the patient to have a second surgical approach, sentinel lymph node biopsy should be performed. 相似文献