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1.
Manuel Steiner Andishe Attarbaschi Margit K nig Helmut Gadner Oskar A. Haas Georg Mann 《Pediatric hematology and oncology》2004,22(1):11-16
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor. 相似文献
2.
Results of Transplanting Developing Third Molars as Part of Orthodontic Space Management 总被引:2,自引:0,他引:2
Oskar Bauss Reza Sadat-Khonsari Werner Engelke Bärbel Kahl-Nieke 《Journal of orofacial orthopedics》2002,63(6):483-492
PATIENTS AND METHOD: The aim of the present study was to contribute to a more accurate indication and better integration of developing third molar transplantation into orthodontic space management, using the results gleaned from the authors' own pool of patients. For this purpose, a clinical and radiographic examination of 61 transplanted developing molars in 57 patients was carried out after an average of 3.3 years. RESULTS: The overall success rate was 85%. Failure was due in 10% of cases to impaired periodontal healing (inflammatory root resorption, ankylosis, or increased pocket probing depths) and in 5% of cases to insufficient or arrested postoperative root development accompanied by increased transplant mobility. The incidence of postoperative cessation of further root development was significantly higher (p = 0.011) in transplants at early developmental stages, which also had a negative impact on the final root length, the crown-root ratio and the mobility values of these transplants. CONCLUSIONS: The transplantation of developing third molars should be given stronger consideration in treatment plans for orthodontic space management although it represents a real alternative to orthodontic space closure only in exceptional cases. However, unlike implantological or prosthodontic treatment, it offers an opportunity to replace a missing or non-retainable tooth with a patient's own vital and fully functional tooth, provided the appropriate transplant is selected. 相似文献
3.
Mechanical function of intermediate filaments in arteries of different size examined using desmin deficient mice 总被引:2,自引:1,他引:1
Oskar Karlsson Wede Mia Löfgren Zhenlin Li† Denise Paulin† ers Arner 《The Journal of physiology》2002,540(3):941-949
Protein composition and mechanical function of intermediate filaments were examined in arteries of different sizes using desmin deficient mice (Des−/−) and their wild-type controls (Des+/+). Using SDS-PAGE gels and Western blots we found a gradient in desmin expression in the arterial tree; the desmin content increased from the elastic artery aorta, via the muscular mesenteric artery to the resistance-sized mesenteric microarteries ∼150 μm in diameter in Des+/+ mice. Mechanical experiments were performed on the aorta, the mesenteric artery and resistance-sized arteries using wire myographs. For aorta and mesenteric artery, no differences in passive or active circumference- stress relations were found between Des−/− and Des+/+ mice. In microarteries, both passive and active stress were lower in the Des−/− group. In conclusion, large elastic and muscular arteries contain a relatively low amount of desmin, and the desmin intermediate filaments do not seem to play a major role in the mechanical properties of these larger arterial vessels. In the microarteries, where expression of desmin is high, desmin plays a role in supporting both passive and active tension. 相似文献
4.
Abstract – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P = 0.028) or with increased overjet and inadequate lip coverage ( P = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition. 相似文献
5.
Oskar Meggeneder 《Zeitschrift fur Gesundheitswissenschaften》2007,15(2):101-107
In a small company, the whole company culture, including the management style, is dominated by the owner. The management culture
in small companies and above all the management style of the owner determine the chances of successfully introducing workplace
health promotion (WHP). For this reason a typology was developed that describes the management personalities who affect the
company culture in small enterprises. This provides a guide to the possible success of WHP in connection with the management
style. Although a summary of the management and corporate culture of small companies in a few categories cannot show the variety
of social reality, it can provide orientation. The typical categories of company social order (a mixture of ownership and
leadership) in small and medium-sized enterprises are given below. Furthermore, there is an assessment of what the chances
of realising workplace health promotion are in each type of company. Small and medium-sized companies (SME) have a number
of organisational characteristics which are just ideal for the introduction and implementation of workplace health promotion.
The work of the employer and employees is often the same. Information in the company is generally comprehensive and easily
available. The lack of information which employees often complain about in large companies is not a problem. There is a good
flow of communication. Small companies have a flat hierarchy that enables participation, the essential requirement for WHP.
There is a close social relationship between the company head and the workforce, although it must be said that this closeness
can be dangerous, particularly if it is misused as complete social control. The readiness to implement Workplace Health Promotion
(WHP) in SME and the degree of success depends largely on the personality of the company manager and the style of leadership.
Considering the importance of a manager’s personality for WHP in SME, modules and instruments to assist company owners and
managers in SME are to be developed. On behalf of and in co-operation with the Austrian Network for Workplace Health Promotion
several modules have been introduced to assist owners and managers of SMEs. 相似文献
6.
Johannsson OT Staff S Vallon-Christersson J Kytöla S Gudjonsson T Rennstam K Hedenfalk IA Adeyinka A Kjellén E Wennerberg J Baldetorp B Petersen OW Olsson H Oredsson S Isola J Borg A 《Laboratory investigation; a journal of technical methods and pathology》2003,83(3):387-396
A human tumor xenograft (L56Br-X1) was established from a breast cancer axillary lymph node metastasis of a 53-year-old woman with a BRCA1 germ-line nonsense mutation (1806C>T; Q563X), and a cell line (L56Br-C1) was subsequently derived from the xenograft. The xenograft carries only the mutant BRCA1 allele and expresses mutant BRCA1 mRNA but no BRCA1 protein as determined by immunoprecipitation or Western blotting. The primary tumor, lymph node metastasis, and xenograft were hypodiploid by DNA flow cytometry, whereas the cell line displayed an aneuploidy apparently developed via polyploidization. Cytogenetic analysis, spectral karyotyping, and comparative genomic hybridization of the cell line revealed a highly complex karyotype with numerous unbalanced translocations. The xenograft and cell line had retained a somatic TP53 missense mutation (S215I) originating from the primary tumors, as well as a lack of immunohistochemically detectable expression of steroid hormone receptors, epidermal growth factor receptor, human epidermal growth factor receptor 2 (HER-2), and keratin 8. Global gene expression analysis by cDNA microarrays supported a correlation between the expression profiles of the primary tumor, lymph node metastasis, xenograft, and cell line. We conclude that L56Br-X1 and L56Br-C1 are useful model systems for studies of the pathogenesis and new therapeutic modalities of BRCA1-induced human breast cancer. 相似文献
7.
Wolf M von Siebenthal K Keel M Dietz V Baenziger O Bucher HU 《Journal of biomedical optics》2002,7(2):221-227
Three methods by which to determine absolute total cerebral hemoglobin concentration (tHb in micromol/L) by near-infrared spectrophotometry (NIRS) have evolved: (1) tHbo, requiring oxygenation changes and arterial oxygen saturation measurements as a reference using a relative NIRS algorithm, (2) tHbg, using a geometrical multidistance principle and (3) tHbgo, a combination of both. The aim of this study was to compare the three methods quantitatively. Sixteen clinically stable preterm infants with a mean gestational age of 29.6 (range of 25.1-36.4) weeks, birthweight of 1386 (680-2820) g and a postnatal age of 2.5 (0.5-6) days, who needed supplemental oxygen, were enrolled. The mean+/-standard deviation tHbg was 150.2+/-41.8 micromol/L (range of 61.6-228.9 micromol/L), the tHbo was 62.1+/-27.2 micromol/L (26.0-110.8 micromol/L) and the tHbgo was 89.3+/-45.6 micromol/L (26.5-195.9 micromol/L). The correlation coefficient among the three methods were tHbg and tHbgo r=0.736; tHbo and tHbgo r=0.938; tHbg and tHbo r=0.598. A multiple regression with variable selection by Mellow's C(p) showed, that tHbg was correlated to the birthweight, the postnatal age, the heart rate and the pCO2 (r(2)=0.588), tHbo and tHbgo were associated with the hemoglobin concentration in the blood, the mean arterial blood pressure and the pCO2 (r(2)=0.493 and 0.406, respectively). The three methods (tHbg, tHbo, and tHbgo) give systematically different tHb readings and large intersubject variability. 相似文献
8.
Oskar Nuyken Gerhard Maier Aurelia Groß Herbert Fischer 《Macromolecular chemistry and physics.》1996,197(1):83-95
The termination reaction of the cationic polymerization of 2-phenyl- and 2-nonyl-2-oxazolines was examined by reacting the corresponding model oxazolinium salts having tosylate and trifluoromethansulfonate counterions with various nucleophiles. The reaction was monitored by 1H NMR spectroscopy. Piperidine and KOH react with the oxazolinium salts very fast and quantitatively. In the case of piperidine, the use of a double molar amount of piperidine is necessary to achieve complete conversion. The addition of piperidine, pyridine, 4-dimethylaminopyridine and morpholine takes place in position 5 of the oxazolinium ring, whereas water and KOH add in position 2. The rate of the termination reaction depends on the electron density of the nucleophile which can be correlated with the pKa value. With CF3SO as counterion the addition of nucleophiles in position 5 is distinctly faster, whereas the addition of water in position 2 is much slower than with TsO? as counterion. The ring-opening of the nonyl oxazolinium ion is slower than that of the phenyl oxazolinium ion. 相似文献
9.
Doz. Dr. Oskar von Zimmermann-Meinzingen 《Journal of molecular medicine (Berlin, Germany)》1941,20(45):1113-1119
Zusammenfassung Es wurden 12 Fälle von akutem Myokardinfarkt beschrieben, bei denen das wichtige Symptom des stenokardischen Anfalles nicht in Erscheinung getreten war. In einem Falle lag bei einem dekompensierten Rechtsherzen eine embolisch bedingte Infarzierung vor, in allen übrigen Fällen handelte es sich um Coronarthrombosen bei Hypertonieherzen mit schweren Coronarsklerosen und meist auch alten Myokardschwielen. Symptomatisch boten 3 Patienten apoplektiforme Krankheitsbilder, 2 weitere Verworrenheitszustände, 4 schwere Asthma cardiale-Anfälle mit Lungenödem. Zweimal kam es zu Coronarthrombosen während typischer Bronchopneumonien. In allen Fällen war die dauernde Schmerzfreiheit das auffallendste Moment, wobei gleichzeitig auch die akute Shockwirkung bis auf einen Fall vermißt wurde. In diesem Falle handelte es sich um einen schweren Diabetes, der durch den Myokardinfarkt mit ausgeprägter Shockwirkung in ein präkomatöses Stadium kam, während 2 andere schwere, aber schon eingestellte Diabetesfälle bei Auftreten eines Myokardinfarktes sine dolore keine Verschlechterung ihrer Stoffwechsellage erkennen ließen. Nach kurzem Überblick über die Krankengeschichten und Autopsiebefunde der Patienten wurden die Ekg.-Befunde erörtert und teilweise mit Abbildungen belegt. In keinem der Fälle, die nach dem Auftreten des frischen Myokardinfarktes elektrokardiographisch registriert wurden, lag ein typisches Infarktelektrokardiogramm vor, so daß auch die ekg. Diagnostik in diesen Fällen im Stiche ließ. Zweimal wurde bloß ein diskordantes Lävogramm gefunden, wobei wir den Standpunkt vertreten, daß diesem Ekg.-Typus nicht bloß eine Linkshypertrophieform, sondern auch der Ausdruck einer Coronarinsuffizienz zuzusprechen ist, während die Überwertung von Q-Zacken, die bloß in Ableitung III aufscheinen, abgelehnt wird. Abschließend wird auf den häufigen Widerspruch zwischen Elektrokardiogramm und klinischer Diagnostik eingegangen und die strikte Unterordnung der Ekg.-Diagnostik unter die gesamte klinische Diagnostik gefordert. 相似文献
10.
Oskar Nuyken Günter Lattermann Wolfgang Dannhorn Rainer Vogel 《Macromolecular chemistry and physics.》1992,193(5):1057-1069
Poly(epichlorohydrin) and poly(epichlorohydrin-co-ethylene oxide) were modified by reaction with potassium thiocyanate (KSCN), tetrabutylammonium p-toluenesulfinate (NBu4SO2C7H7) and tetrabutylammonium benzenesulfinate (NBu4SO2C6H5). Though the substitution of chlorine in the polymers with these nucleophilic reagents in most cases is accompanied by side reactions, appropriate reaction conditions allow degrees of substitution higher than 90% to be obtained. The glass transition temperature (Tg) of the thiocyanate-modified homo- and copolymer exhibits only a small increase with increasing degree of substitution. While the Tg of the original homo- and copolymer is observed at ?20°C and ?38°C, respectively, the glass transition of the highly substituted homopolymer occurs at ?12°C and for the copolymer at ?31°C. On the other hand, the thiocyanate-modified polymers show a remarkably higher decomposition temperature of about 250°C as compared with that of the unmodified polymers (160–180°C). In addition, the solubility is markedly influenced by the substitution. While the original homo- and copolymers are soluble in, e.g., benzene and toluene, the highly modified products are only soluble in polar solvents such as THF, acetone, DMSO and diglyme. Introducing sulfonyl groups, the resulting polymers exhibit a glass transition temperature increased to a greater extent. For the homopolymer with the highest degree of substitution (98,3%), a Tg of 73°C is observed. Concerning the decomposition temperature, a drastical increase up to 370°C occurs. Finally the influence of phase transfer catalysts on the described reactions was investigated. 相似文献