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1.
In the treatment of massive hematuria after renal biopsy, selective percutaneous vaso-occlusion with detachable balloons is an effective alternative to urological surgery, as demonstrated in the case of a 39-year-old man. A review of the literature, which records success rate of more than 90% in nonmalignant renal hemorrhage, confirms the therapeutic value of the various parenchyma-sparing embolization techniques. 相似文献
2.
Ectopic bone formation associated with mesenchymal stem cells in a resorbable calcium deficient hydroxyapatite carrier 总被引:6,自引:0,他引:6
Kasten P Vogel J Luginbühl R Niemeyer P Tonak M Lorenz H Helbig L Weiss S Fellenberg J Leo A Simank HG Richter W 《Biomaterials》2005,26(29):5879-5889
Bone substitute materials can induce bone formation in combination with mesenchymal stem cells (MSC). The aim of the current study was to examine ectopic in vivo bone formation with and without MSC on a new resorbable ceramic, called calcium deficient hydroxyapatite (CDHA). Ceramic blocks characterized by a large surface (48 m2/g) were compared with beta-tricalcium phosphate (beta-TCP), hydroxyapatite (HA) ceramics (both ca. 0.5 m2/g surface) and demineralized bone matrix (DBM). Before implantation in the back of SCID mice carriers were freshly loaded with 2x10(5) expanded human MSC or loaded with cells and kept under osteogenic conditions for two weeks in vitro. Culture conditions were kept free of xenogenic supplements. Deposits of osteoid at the margins of ceramic pores occurred independent of osteogenic pre-induction, contained human cells, and appeared in 416 MSC/CDHA composites compared to 216 MSC/beta-TCP composites. ALP activity was significantly higher in samples with MSC versus empty controls (p<0.001). Furthermore, ALP was significantly (p<0.05) higher for all ceramics when compared to the DBM matrix. Compared to previous studies, overall bone formation appeared to be reduced possibly due to the strict human protocol. Ectopic bone formation in the novel biomaterial CDHA varied considerably with the cell pool and was at least equal to beta-TCP blocks. 相似文献
3.
Prof. Dr. Richard Jung Wiltrud Berger 《European archives of psychiatry and clinical neuroscience》1979,227(4):279-300
Zusammenfassung Zum 50. Jahr seiner ersten EEG-Publikation werden Bergers frühe EEG-Ableitungen von 1924–1931 aus dem Freiburger Berger-Archiv besprochen und illustriert.Drei Arten der frühen Untersuchungen Bergers werden im einzelnen besprochen: 1. Saitengalvanometerableitungen von 1924–1926 vorwiegend bei Patienten mit Knochenlücken, die bei diesen Patienten mit Hirnerkrankungen verlangsamte Grundrhythmen von 6–8/s zeigten. 2. Die direkte Ableitung von Rinde und Mark eines trepanierten Patienten 1930, die den Ursprung des EEG in der Hirnrinde klar nachwies. 3. Typische unpublizierte EEG-Befunde bei Epilepsien 1930–1931 im Anfallsintervall und bei Absencen werden abgebildet.In Bergers ersten 6 Mitteilungen, die alle wesentlichen EEG-Befunde bei Hirnerkrankungen und die EEG-Veränderungen bei Aufmerksamkeit, Schlaf und Narkose beschreiben, fehlen diese in Abb. 4–7 illustrierten EEG-Kurven von Krampfpotentialen. Berger hat seine Epilepsie-Befunde zunächst zurückgehalten, weil er Bewegungsartefakte befürchtete und seine Kontrollen ähnliche Formen bei Lid- und Stirnbewegungen zeigten (Abb. 4a, b).Erst 1933, nachdem andere Untersuchungen über experimentelle Epilepsie bei Tieren das Vorkommen abnorm großer Krampfentladungen der Hirnrinde nachwiesen, wagte Berger in der 7. Mitteilung EEG-Ausschnitte eines Petit-mal-Anfalls und fokaler Anfälle bei Paralyse zu publizieren. In einer Synopsis des EEG 1938 illustrierte Berger den Beginn einer Absence mit großen 3/s-Wellen, die den von Gibbs und Lennox 1934 als spike and wave bezeichneten Formen entsprachen. Berger deutete 1933 die abnormen steilen und unregelmäßigen Hirnpotentialformen als Afallsbereitschaft des Großhirns und die Perioden großer 3/s-Wellen als corticale Begleiterscheinungen der Absencen.Die Arbeit wurde vom Sonderforschungsbereich Hirnforschung und Sinnesphysiologie (SFB 70) unterstützt. 相似文献
4.
The access to defined protein-based material systems is a major challenge in bionanotechnology and regenerative medicine. Exact control over sequence composition and modification is an important requirement for the intentional design of structure and function. Herein structural- and matrix proteins provide a great potential, but their large repetitive sequences pose a major challenge in their assembly. Here we introduce an integrative “one-vector-toolbox-platform” (OVTP) approach which is fast, efficient and reliable. The OVTP allows for the assembly, multimerization, intentional arrangement and direct translation of defined molecular DNA-tecton libraries, in combination with the selective functionalization of the yielded protein-tecton libraries. The diversity of the generated tectons ranges from elastine-, resilin, silk- to epitope sequence elements. OVTP comprises the expandability of modular biohybrid-materials via the assembly of defined multi-block domain genes and genetically encoded unnatural amino acids (UAA) for site-selective chemical modification. Thus, allowing for the modular combination of the protein-tecton library components and their functional expansion with chemical libraries via UAA functional groups with bioorthogonal reactivity. OVTP enables access to multitudes of defined protein-based biohybrid-materials for self-assembled superstructures such as nanoreactors and nanobiomaterials, e.g. for approaches in biotechnology and individualized regenerative medicine. 相似文献
5.
OBJECTIVE: To investigate the contribution of clinical ex vivo expansion protocols to replicative aging of human chondrocytes. METHODS: Primary human chondrocytes were cultured as monolayers after isolation from 7 articular cartilage specimens. Cells were passaged corresponding to 12-19 cell population doublings (cpd). Aliquots of the cells were collected from each passage and analyzed for telomere length and telomerase activity. RESULTS: The rate of telomere shortening was heterogeneous, ranging from 147 to 431 bp/cpd (mean +/- SD 305 +/- 122). Telomerase activity was detected at various time points during passaging in 5 of 7 primary chondrocytes analyzed, but not in native human articular cartilage specimens. According to our data, an 8-10-fold ( approximately 3 cpd) ex vivo expansion of articular chondrocytes, as typically performed for transplantation procedures, leads to telomere erosion in the range of 900 bp. This is comparable with 30 years of aging based on the in vivo rate of telomere shortening of 30 bp/year recently found in chondrocytes. CONCLUSION: If telomere shortening is an important determinant of aging in human articular cartilage, an additional telomere loss due to ex vivo expansion might affect the incidence or time of onset of age-related cartilage disorders. However, given the limited extent of expansion performed in the clinical setting to date, a significant telomere-mediated increase in the risk of malignant transformation or replicative exhaustion of the transplanted cells seems unlikely. 相似文献
6.
Bronchoscopy to evaluate hemoptysis in older men with nonsuspicious chest roentgenograms 总被引:2,自引:0,他引:2
Six of 106 older men with hemoptysis and a nonsuspicious chest roentgenogram who underwent fiberoptic bronchoscopy were found to have cancer. Four of the five bronchogenic carcinomas appeared to be surgically resectable. Cancer patients were significantly older, had smoked within the last five years, and had a significantly higher frequency of central abnormalities on chest roentgenogram. Six additional bronchogenic carcinomas were diagnosed at follow-up. Two of these were probably present but not detected at the time of bronchoscopy. We conclude that (1) hemoptysis with a nonsuspicious chest roentgenogram carries an appreciable risk of cancer in older men with substantial smoking histories, (2) these cancers are often resectable, (3) a chest roentgenogram in which the central lung fields are obscured in any way should not be considered negative in patients with hemoptysis, and (4) a negative bronchoscopic examination does not exclude the possibility of cancer in these patients. 相似文献
7.
F A Lederle 《Annals of internal medicine》1990,113(10):731-732
8.
9.
Connie A. Tompkins Margaret Lehman Blake Annette Baumgaertner Wiltrud Fassbinder 《Aphasiology》2013,27(4-6):559-572
Background: Comprehension deficits that typify adults with right brain damage (RBD) have been linked to considerations of processing capacity and processing demands, as well as to ineffective suppression of mental activation that is incompatible with a contextually intended interpretation. Aims: As a first step in investigating how processing resource factors and more specific difficulties like suppression deficits interact to yield characteristic RBD comprehension patterns, the current study was designed to assess whether suppression function consumes attention. Methods & Procedures: A total of 28 RBD and 22 non-brain-damaged adults listened to sentence stimuli that biased the meaning of a sentence-final lexical ambiguity (e.g., “spade”). The suppression task involved speeded judgements of whether a subsequent spoken probe word fitted the overall sentence meaning. In experimental stimuli, the probe word (e.g., “cards”) was unrelated to the biased meaning of the ambiguity. Comparison stimuli ended in an unambiguous word (e.g., “shovel”) that was clearly unrelated to the spoken probe. Thus, slowness after an experimental sentence, relative to its comparison sentence, indicated that the contextually inappropriate meaning of the experimental ambiguity interfered with the probesentence relatedness judgement (i.e., had not been suppressed). In two dual-task conditions, participants allocated 20% or 50% of their “brain power” to a concurrent secondary task, reporting orally whether the probe word consisted of one or two syllables. Outcomes & Results: For both groups, suppression of contextually unintended meanings of lexical ambiguities was more effective in a single-task condition than when attention was shared with a secondary task. The secondary syllable-counting task also suffered when allocated less attention. Conclusions: Effective suppression consumes finite processing capacity. As elaborated in the paper, several combinations of these variables could underlie relatively good and poor comprehension after RBD. Researchers and clinicians need to keep in mind such potential interactions of ineffective comprehension mechanisms, stimulus/task processing demands, and processing capacity. 相似文献
10.
Wiltrud Richter Karin M. Jury Daniela Loeffler Burkhard J. Manfras Thomas H. Eiermann Bernhard O. Boehm 《European journal of immunology》1995,25(6):1703-1712
Insulin-dependent (type 1) diabetes mellitus is an organ-specific autoimmune disease frequently associated with an islet-specific humoral autoimmune response. The role of islet cell autoantibodies in the disease process is unclear; in particular, it is not known whether they are a non-specific side effect of islet cell destruction or play a role in the autoimmune network leading to type 1 diabetes. Here we report the immunoglobulin gene usage and somatic mutation rates of a panel of seven human monoclonal islet cell autoantibodies (MICA 1–7) directed towards the major islet cell autoantigen glutamate decarboxylase (GAD). These autoantibodies were produced from cells from two patients with newly diagnosed type 1 diabetes. VH1, VH4 and Vλ2 gene segments were frequently used in the MICA, but no correlation between V gene usage and epitope recognition was found. The nonrandom ratio of replacement versus silent mutations in the variable gene region, an accumulation of replacement mutations in the complementarity determining regions, which confer antigen binding, and the high relative avidity for GAD observed for MICA 1, 3, 4, and 6, suggested that the immune response to GAD is driven by the antigen. In contrast, MICA 2, 5, and 7, revealing a lower affinity for antigen, have accumulated a large number of silent mutations. These latter antibodies may, therefore, be characteristic for later stages of the chronic autoimmune disease. Our results argue in favor of an antigen-driven autoantibody response to islets in human type 1 diabetes. They suggest that GAD is an important target of autoimmunity associated with type 1 diabetes. 相似文献