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41.
Claudia Breitkopf Ludwig Suter 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1995,46(7):502-504
Zusammenfassung
Bei einer 71j?hrigen Frau trat nach R?ntgenweichstrahltherapie an der Nase (Gesamtdosis 28 Gy, Gewebehalbwerttiefe 10,5–11,5
mm) eine ausgepr?gte Strahlenerosion auf. Diese zeigte 5 Wochen nach Ende der Bestrahlung noch keine Tendenz zur Abheilung.
Ursache dieses ungew?hnlichen Verlaufes war ein gleichzeitig bestehender Pemphigus vulgaris. Dieser hatte sich nach der Strahlentherapie,
vermutlich als Folge einer Freisetzung epidermaler Antigene, verschlimmert. Da? der Pemphigus in diesem Fall durch die Bestrahlung
ausgel?st wurde – wie mehrfach in der Literatur berichtet – ist unwahrscheinlich, aber nicht sicher auszuschlie?en.
Eingegangen am 11. April 1994 Angenommen am 10. Juni 1994 相似文献
42.
Carlotta Castagnoli Claudia Trombotto Sabzima Ondei Maurizio Stella Maurizio Calcagni Gilberto Magliacani Simone Teich Alasia 《Burns : journal of the International Society for Burn Injuries》1997,23(7-8):565-572
In this study, skin-infiltrating cells were characterized in both the active and remission phases of post-burn hypertrophic scar biopstes. Immunohistochemistry examination of active phase samples showed an abundant presence of Langerhans cells, T cells, macrophages, a low presence of natural killer cells and the lack of B lymphocytes. In active hypertrophic scars T lymphocytes infiltrate deep into the superficial dermis and are also observed in the epidermis: CD3+ cells were present at about 222±107 per 0.25 mm2. In particular the analysis of lymphocyte subpopulations showed that CD4+ T cells predominate in the dermis as well as in the epidermis of active hypertrophic scars whereas CD8+ cells were less well represented (CD4/CD8 ratio is 2.06). This distribution was also shown in remission phase samples and in normotrophic scar specimens, although the lymphocyte number was significantly lower. Approximately 70 per cent of T lymphocytes present in the tissue involved in active phase hypertrophic scar samples were activated (positive with anti-HLA-DR and IL-2 receptor antibodies) which is significantly higher than remission phase hypertrophic and normotrophic scars, in which positivity was 40 and 38 per cent, respectively. Upon activation, the lesional lymphocytes release several cytokines, locally and transiently, that interact with specific receptors in response to different stimulation. Central to the immune hypothesis of hypertrophic scars is that some of the T-cell lymphokines act on keratinocytes, fibroblasts and other cell types to induce changes characteristic of these scars. The presence and close proximity of activated T lymphocytes and antigen-presenting cells of various phenotypes in both the epidermis and dermis of hypertrophic tissues provides strong circumstantial evidence of a local immune response. However, the manner in which T cells achieve and maintain their activated state in hypertrophic tissues in not yet known, and both antigen-dependent and independent mechanisms may contribute. 相似文献
43.
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45.
Ruth Ladurner Gerald Brandacher Wolfgang Steurer Stefan Schneeberger Claudia Bösmüller Martin Clemens Freund Alfons Kreczy Alfred Königsrainer Raimund Margreiter 《Transplant international》2003,16(12):885-889
Fungal infections still represent a serious complication after organ transplantation. Early diagnosis and aggressive treatment are crucial. Because of the many diagnostic problems involved, we present a case of mucormycosis--primarily affecting the paranasal sinuses with later intracranial extension--in a highly immunized recipient of a third renal transplant. Although fungal infection was suspected from various imaging techniques, only the detection of typical fungal hyphae in the infected tissue was diagnostic. Neither the blood tests and cerebrospinal fluid examinations performed nor cultures from maxillary sinus fluid were of any diagnostic help. Surgical debridement from a transnasal as well as an intracranial approach and systemic amphotericin B together with the discontinuation of immunosuppression after removal of the rejected graft were able to save the patient. This case stresses the importance of early diagnosis that can only be made from tissue biopsies and allows appropriate timely treatment. 相似文献
46.
Julieta Ramos-Loyo Andrés Antonio Gonzalez-Garrido Claudia Amezcua Miguel A Guevara 《International journal of psychophysiology》2004,54(3):251-262
In spite of previous reports on the relationship between ongoing EEG and ERPs, there remains a lack of agreement on the nature of their nexuses. The aim of the present study was to evaluate the relationship between resting EEG and the ERP components in two groups of healthy subjects with different levels of performance in a highly demanding selective visual attention task. Young adults were classified according to the amount of their correct responses in the task, into high (HP; averaged hits (AH): 86%) and low performance groups (LP; AH: 59%). EEG was recorded during rest, prior to task performance and absolute (AP) and relative power (RP), as well as inter- (rTER) and intrahemispheric (rTRA) correlation were calculated. ERPs during task performance were also obtained and their amplitude and latency measures were assessed. Results showed that individuals with better behavioral performance had a higher synchronization between both hemispheres during rest as well as higher amplitude and shorter latencies of N2 and P3. Principal Component Analysis revealed that alpha2 AP and RP were inversely related to P2 and N2 latency. Higher values of alpha1 and alpha2 rTER were clustered with higher P3 amplitude and shorter reaction time. In conclusion, the differences in the cortical organization of HP and LP at rest (EEG) seem to be associated to the way the brain reacts during information processing (ERPs). 相似文献
47.
48.
Rafael T Mikolajczyk Maren Bredehorst Nadia Khelaifat Claudia Maier Annette E Maxwell 《BMC public health》2007,7(1):21
Background
The prevalence of depression is increasing not only among adults, but also among adolescents. Several risk factors for depression in youth have been identified, including female gender, increasing age, lower socio-economic status, and Latino ethnic background. The literature is divided regarding the role of acculturation as risk factor among Latino youth. We analyzed the correlates of depressive symptoms among Latino and Non-Latino White adolescents residing in California with a special focus on acculturation. 相似文献49.
Claudia Ehringer Mikulaninec 《Patient education and counseling》1987,10(3):253-265
This study sought to contrast mailing a booklet to accomplish preoperative instruction with teaching performed by nurses after hospital admission. Sixty-six patients were studied in a 700-bed medical center and were assigned to three teaching groups and a control group which did not receive teaching. The researcher compared the four groups preoperatively after admission to determine the patients' knowledge and ability to perform surgical exercises, as well as their anxiety levels.
Findings were that patients who received a booklet by mail preadmission learned surgical exercises equally well compared to patients taught postadmission, and mastered significantly more exercise behaviors than those receiving no instruction. No statistical difference in anxiety level was found among groups. One may infer that mailing preadmission material should be considered as an effective teaching mode and alternative to postadmission instruction. 相似文献
50.
Henryk Barthel Michael Wiener Claudia Dannenberg Simone Bettin Bernhard Sattler Wolfram H. Knapp 《European journal of nuclear medicine and molecular imaging》1997,24(10):1245-1252
This study addresses the question of whether the normal range for distribution of local cerebral blood flow (lCBF) in adults
can be transferred to the 4- to 15-year-old age group. Twenty-three children (age: 4–15 years; mean 11±3 years, group I) and
10 adults (age: 27–56 years; mean 45±10 years, group II) without evidence of cerebrovascular disease or other brain diseases
underwent technetium-99m ethyl cysteinate dimer single-photon emission tomography. Counts in cortical and subcortical regions
of interest (ROIs) were related to those in cerebellar ROIs (= 100%). Relative cortical activity in group I exceeded that
in group II, particularly in left parietal (107.6%±9.8% vs 84.1%±12.4%), left frontal (97.7%±6.7% vs 79.4%±8.9%) and left
temporal areas (99.7%±7.4% vs 84.9%±10.1%) and in the cingulate cortex (112.1%±9.1% vs 95.9%±10.1%, P<0.05). Cerebral activity uptake per injected dose was inversely correlated with age in 19 children of group I (r = –0.77, P<0.001). In group I, there was also an inverse correlation between age and the relative local count density in the parietal
(r = –0.42 to –0.57), frontal (r = –0.48), temporal (r = –0.42 to –0.58) and occipital cortex (r = –0.44). In these cortical regions relative counts differed when subgroups of children aged 4–10 and 11–15 years were analysed.
It is concluded that there are systematic differences between 4- to 15-year-old children and adults with regard to normal
lCBF. Diagnostic use of perfusion agents has to consider age-adjusted normal flow maps; normal ranges should be determined
separately for the age groups 4–10 and 11–15 years.
Received 23 March and in revised form 11 July 1997 相似文献