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51.
Jessica Lasky-Su Tobias Banaschewski Jan Buitelaar Barbara Franke Keeley Brookes Edmund Sonuga-Barke Richard Ebstein Jacques Eisenberg Michael Gill Iris Manor Ana Miranda Fernando Mulas Robert D Oades Herbert Roeyers Aribert Rothenberger Joseph Sergeant Hans-Christoph Steinhausen Eric Taylor Kaixin Zhou Margaret Thompson Philip Asherson Stephen V Faraone 《Neuropsychopharmacology》2007,62(9):985-990
BACKGROUND: Previous research found an association between single nucleotide polymorphisms (SNPs) in the promoter region of DRD4 and statistically derived phenotypes generated from attention-deficit/hyperactivity disorder (ADHD) symptoms. We sought to replicate this finding by using the same methodology in an independent sample of ADHD individuals. METHODS: Four SNPs were genotyped in and around DRD4 in 2631 individuals in 642 families. We developed a quantitative phenotype at each SNP by weighting nine inattentive and nine hyperactive-impulsive symptoms. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, the screening procedure implemented in PBAT was used to select and test the five SNPs/genetic model combinations with the greatest power to detect an association for DRD4. RESULTS: One of the four SNPs was associated with the quantitative phenotypes generated from the ADHD symptoms (corrected p-values = .02). A rank ordering of the correlation between each of the ADHD symptoms and the quantitative phenotype suggested that hyperactive-impulsive symptoms were more strongly correlated with the phenotype; however, including inattentive symptoms was necessary to achieve a significant result. CONCLUSIONS: This study partially replicated a previous finding by identifying an association between rs7124601 and a quantitative trait generated from ADHD symptoms. The rs7124601 is in linkage disequilibrium (LD) with the SNPs identified previously. In contrast to the previous study, this finding suggests that both hyperactive-impulsive and inattentive symptoms are important in the association. 相似文献
52.
Nikolaus A Haas Christoph K Camphausen 《Pediatric critical care medicine》2006,7(4):399; author reply 399-399; author reply 400
53.
54.
Tobias Forschner Stefan Buchholtz Eggert Stockfleth 《Journal der Deutschen Dermatologischen Gesellschaft》2007,5(6):467-475
Vitiligo is a skin disease with a worldwide prevalence ranging from 0.5% to 4%. Conservative therapies include photochemotherapy, phototherapy with UVB radiation (broadband UVB 290–320 nm, narrow band UVB 311 nm), systemic steroids and pseudocatalase. Modern therapeutic options include treatment with topical immunomodulators (tacrolimus, pimecrolimus), analogues of vitamin D3, excimer laser and surgery/transplantation. Our analysis compares these therapies for vitiligo and the evidence levels supporting their effectiveness. Conclusions: The face and neck respond best to all therapeutic approaches, while the acral areas are least responsive. For generalized vitiligo, phototherapy with UVB radiation is most effective with the fewest side effects; PUVA is the second best choice.Topical corticosteroids are the preferred drugs for localized vitiligo. They may be replaced by topical immunomodulators which display comparable effectiveness and fewer side effects.The effectiveness of vitamin D analogues is controversial with limited data. Surgical therapy can be very successful, but requires an experienced surgeon and is very demanding of time and facilities, thus limiting its widespread use. L-phenylalanine therapy appears effective on the face but enjoys neither widespread use nor extensive data support. No single therapy for vitiligo can be regarded as the most effective as the success of each treatment modality depends on the type and location of vitiligo. 相似文献
55.
Whole-heart cine MRI using real-time respiratory self-gating. 总被引:1,自引:0,他引:1
Sergio Uribe Vivek Muthurangu Redha Boubertakh Tobias Schaeffter Reza Razavi Derek L G Hill Michael S Hansen 《Magnetic resonance in medicine》2007,57(3):606-613
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach. 相似文献
56.
Dr. med. D.-H. Boack Prof. Dr. G. Bogusch Univ.-Prof. Dr. Th. Mittlmeier Univ.-Prof. Dr. N. P. Haas 《Fu? & Sprunggelenk》2005,3(1):9-18
Zusammenfassung
Nach Verifikation der anatomischen Voraussetzungen wurde eine modifizierte Technik des erweiterten saphenofasziokutanen Suralislappen für große kombinierte Knochen-Weichteil-Infekt-Defekt-Situationen sogenannte Typ-C-Läsionen bei Risikopatienten mit ersatzschwachem bzw. ersatzunfähigem Lager (traumatische ipsilaterale arterielle Hauptgefäßläsion, tiefe ipsilaterale Venenthrombose, diabetische Polyneuropathie mit Mikroangiopathie bzw. PAVK Stadium 3) in einer prospektiven Studie angewendet. Zehn Weichteildefekte zwischen 80–180 cm2 im Mittel-Rückfuß- bzw. distalen Unterschenkelbereich wurden einzeitig komplett mit einem retrograd gestielten modifizierten saphenofasziokutanen Suralislappen aus dem proximalen Unterschenkel gedeckt. Alle Lappen heilten ohne Lappennekrosen ein. Die Entnahmestellen wurden siebenmal mittels primärer Naht und dreimal einzeitig mit Meshgraft verschlossen. Bei der Nachuntersuchung aller Patienten nach im Mittel 22 Monaten bestanden vitale Lappen, keine Hebedefektmorbidität, kein Suralisneurom und es war kein sekundäres Debulking oder andere lappeninduzierte Revisionen erforderlich. 相似文献
57.
Richard Werner Karsten Alfke Tobias Schaeffter Arya Nabavi H Maximilian Mehdorn Olav Jansen 《Magnetic resonance in medicine》2004,52(6):1443-1447
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast. 相似文献
58.
G Calaminus D Vesterling-H?rner J P B?kkerink H Gadner G Günther H J Haas H Jürgens C Teske U G?bel 《Klinische P?diatrie》1991,203(4):246-250
The cooperative therapy study MAKEI 83/86 included an examination of the prognostic value of the AFP in children and adolescents with extracranial non-testicular yolk sac tumors. The serum AFP values of 72 protocol- and follow-up-patients were documented at diagnosis and up to the ninth month of treatment. 32 of these patients had saccrococcygeal tumors, 27 had tumors of the ovary and 13 suffered from extragonadal germ cell-tumors. 4 children showed progressive disease under initial chemotherapy and 1 patient died of therapy, 10 of 72 patients relapsed. The AFP measurements were plotted on semilogarithmic charts. They were compared to the measurements of healthy children up to the age of 1 year. According to the development of the patients' AFP values compared to the reference curves the following classifications could be made: 1. Patients with a normal AFP-decrease id est 50% in less than or equal to 6 days during the 1st month of therapy: 48/72 patients 2. Patients with slow AFP-decrease: 17/72 patients 3. Patients with transient AFP-decrease: 5/72 patients 4. Patients with no AFP-decrease: 2/72 patients According to Kaplan-Meier life table analysis, patients with a normal AFP-decrease had an event-free survival of 89% +/- 4%, whereas all other patients showed an event-free survival of 63% +/- 10% (p less than 0.05). Regarding primary therapy id est tumor resection or preoperative chemotherapy an equal distribution of the patients among those with a normal and slow AFP-decrease was observed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
59.
Elimination of bacteria on different implant surfaces through photosensitization and soft laser. An in vitro study. 总被引:2,自引:0,他引:2
Robert Haas Orhun Dörtbudak Nikoletta Mensdorffpouilly Georg Mailath 《Clinical oral implants research》1997,8(4):249-254
Microbiologic examinations of implants have shown that certain micro‐organisms described as periodontal pathogens may have an influence on the development and the progression of peri‐implant disease. This experimental study aimed to examine the bactericidal effect of irradiation with a soft laser on bacteria associated with peri‐implantitis following exposure to a photo‐sensitizing substance. Platelets made of commercially pure titanium, either with a machined surface or with a hydroxyapatite or plasma‐flame‐sprayed surface or with a corundum‐blasted and etched surface, were incubated with a pure suspension of Actinobacillus actinomyetemcomitans or Porphyromonas gingivalis or Prevotella intermedia. The surfaces were then treated with a toluidine blue solution and irradiated with a diode soft laser with a wave length of 905 nm for 1 min. None of the smears obtained from the thus treated surfaces showed bacterial growth, whereas the smears obtained from surfaces that had been subjected to only one type of treatment showed unchanged growth of every target organism tested ( P <0.0006). Electron microscopic inspection of the thus treated platelets revealed that combined dye/laser treatment resulted in the destruction of bacterial cells. The present in vitro results indicate that lethal photosensitization may be of use for treatment of peri‐implantitis. 相似文献
60.
Acute megakaryocytic leukemia in children. Clinical, immunologic, and cytogenetic findings in two patients. 总被引:2,自引:0,他引:2
An unusual presentation of acute megakaryocytic leukemia (AMKL) is reported in two young children. The first child had a 10-day history of ptosis of the right eyelid as the initial manifestation of AMKL, a clinical picture not previously described in this variant of leukemia. Computed tomographic scanning showed multiple intracranial mass lesions, and the diagnosis of AMKL was confirmed by immunophenotyping of bone marrow blasts. The second child had Down syndrome and received alkylating agents and radiation therapy for treatment of metastatic rhabdomyosarcoma of the orbit. She had AMKL as second malignancy. Both patients had acquired chromosome 21 anomalies in their leukemic blasts. The first patient, constitutionally normal, had an i(21q) in his leukemic blasts; the patient with constitutional trisomy 21 had tetrasomy 21 and additional chromosomal changes. The clinical symptoms and the results of morphologic, immunologic, and cytogenetic studies are discussed. 相似文献