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排序方式: 共有5170条查询结果,搜索用时 15 毫秒
1.
Schmitz Jan Jansen Stefanie Meyer Moritz Hinkelbein Jochen 《Notfall & Rettungsmedizin》2022,25(4):285-293
Notfall + Rettungsmedizin - Tauchunfälle sind vergleichsweise selten und stellen (Erst‑)Helfer vor besondere Herausforderungen. Sie müssen schnell und kompetent behandelt werden, da... 相似文献
2.
Manuela Kusch Claudia Grundmann Stefanie Keitel Rainer Seitz Herbert K?nig 《Blood coagulation & fibrinolysis》2006,17(7):575-580
A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases. 相似文献
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4.
Klaus Herfarth Heinrich Schmidt-Gayk† Stefanie Graf reas Maier† 《Clinical endocrinology》1992,37(6):511-519
OBJECTIVE: We wished to investigate the circadian rhythm and pulsatility of parathyroid hormone (PTH) secretion in man, as conflicting results have been published. DESIGN AND PATIENTS: To investigate the circadian rhythm during daytime, we sampled (a) peripheral blood at hourly intervals in 12 healthy young men from 0900 h until 1700 h. For observation of pulsatility, we sampled (b) peripheral blood at 1-minute intervals for 1 hour in three healthy men and three healthy women (mean 27.7 years, range 21-56 years) and (c) at 1-minute intervals for 30 minutes in 21 patients with surgically confirmed primary hyperparathyroidism (pHPT). MEASUREMENTS: The serum levels of intact PTH were measured by two-site immunoradiometric assay and special care was taken to reduce intra-assay variability, especially at the normal PTH concentration. In series (a), ionized calcium, total calcium and phosphate were also determined. RESULTS: A circadian rhythm during daytime was found for intact PTH in healthy men and women with a nadir at 0930 h and a peak in the afternoon. Ionized calcium and total calcium (protein-adjusted) decreased and phosphate increased in the afternoon. These changes were all statistically significant (P < 0.02). Pulsatility of PTH: Statistical cluster analysis of the data showed no pulsatility either in healthy persons or in patients with primary hyperparathyroidism. In two healthy women and one healthy man slight changes of longer duration were discovered, but no complete pulses. In five patients with primary hyperparathyroidism, larger differences between the highest and lowest concentrations of intact PTH were found, but no complete pulses. CONCLUSIONS: Our data show a significant circadian rhythm during daytime of intact PTH and only minor changes from minute to minute. The alterations in PTH-levels occurred at longer time intervals in healthy persons. In some patients with primary hyperparathyroidism, decreases of PTH-levels were found. The circadian rhythm of PTH may be due to slight changes in calcium or phosphate concentration. 相似文献
5.
Stefanie Klaffke Andrea A Kuhn Michail Plotkin Holger Amthauer Daniel Harnack Roland Felix Andreas Kupsch 《Movement disorders》2006,21(10):1724-1727
Alterations in presynaptic and postsynaptic dopaminergic system and cerebral glucose metabolism in corticobasal degeneration (CBD) were assessed to evaluate the potential usefulness of different imaging methods for CBD. (123)I-FP-CIT/(123)I-beta-CIT SPECT and (123)I-IBZM SPECT as well as (18)F-FDG PET were performed in eight CBD patients. Decreased presynaptic dopamine transporter binding was found in all CBD patients while D2 receptor binding was reduced in only one patient. (18)F-FDG PET displayed a contralateral hypometabolism in cortical and subcortical areas in seven out of eight patients. Our results demonstrate that glucose metabolism and DAT are reduced, while D2 receptors may be frequently preserved in CBD. 相似文献
6.
7.
Claus Zimmer Stefanie Märzheuser Stephan Patt Arndt Rolfs Joachim Gottschalk Klaus Weigel George Gosztonyi 《Journal of neurology》1992,239(7):394-400
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment. 相似文献
8.
Gudrun Bornh?ft Stefanie Maxion-Bergemann Ursula Wolf Gunver S Kienle Andreas Michalsen Horst C Vollmar Simon Gilbertson Peter F Matthiessen 《BMC medical research methodology》2006,6(1):56
Background
It is often stated that external validity is not sufficiently considered in the assessment of clinical studies. Although tools for its evaluation have been established, there is a lack of awareness of their significance and application. In this article, a comprehensive checklist is presented addressing these relevant criteria. 相似文献9.
S A Rosenberg M T Lotze L M Muul S Leitman A E Chang J T Vetto C A Seipp C Simpson 《Surgery》1986,100(2):262-272
A new approach to cancer therapy has been developed based on the adoptive transfer of autologous lymphokine-activated killer (LAK) cells and recombinant interleukin-2 (IL-2). Forty-one patients with advanced cancer who have failed all standard treatments were treated in this experimental protocol. Fourteen patients experienced an objective regression of cancer, including one patient with metastatic melanoma who underwent a complete regression. Objective responses were seen in patients with colorectal cancer, renal cell cancer, melanoma, and lung adenocarcinoma. The sites of tumor regression included subcutaneous tissue, lung, and liver. The major side effect of therapy resulted from the administration of high-dose IL-2 and was manifested primarily as fluid retention, resulting in a generalized capillary permeability leak syndrome. This approach to adoptive immunotherapy represents a promising approach to the therapy of patients with metastatic cancer. Attempts to increase the potency and decrease the toxicity of therapy and extend this treatment to patients with smaller tumor burdens are in progress. 相似文献
10.
René?G?ddeEmail author Stefanie?Brune Peter?Jagiello Eckhart?Sindern Michael?Haupts Sebastian?Schimrigk Norbert?Müller J?rg?T?Epplen 《Journal of negative results in biomedicine》2005,4(1):7
Apoptosis, the programmed death of cells, plays a distinct role in the etiopathogenesis of Multiple sclerosis (MS), a common
disease of the central nervous system with complex genetic background. Yet, it is not clear whether the impact of apoptosis
is due to altered apoptotic behaviour caused by variations of apoptosis-related genes. Instead, apoptosis in MS may also represent
a secondary response to cellular stress during acute inflammation in the central nervous system. Here, we screened 202 apoptosis-related
genes for association by genotyping 202 microsatellite markers in initially 160 MS patients and 160 controls, both divided
in 4 sets of pooled DNA samples, respectively. When applying Bonferroni correction, no significant differences in allele frequencies
were detected between MS patients and controls. Nevertheless, we chose 7 markers for retyping in individual DNA samples, thereby
eliminating 6 markers from the list of candidates. The remaining candidate, the ERBB3 gene microsatellite, was genotyped in additional 245 MS patients and controls. No association of the ERBB3 marker with the disease was detected in these additional cohorts. In consequence, we did not find further evidence for apoptosis-related
genes as predisposition factors in MS. 相似文献