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81.
MG Astapenko W Otto TM Trofimowa H H?ntzschel B Tautenhahn D Reinelt H Treutler AI Speranskij NM Mylow WA Duljapin TA Tarasenkowa 《Canadian Metallurgical Quarterly》1976,31(16):641-646
On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis. 相似文献
82.
Modification of human platelet adhesion on biomaterial surfaces by protein preadsorption under static and flow conditions 总被引:1,自引:0,他引:1
Otto M Franzen A Hansen T Kirkpatrick CJ 《Journal of materials science. Materials in medicine》2004,15(1):35-42
Biomaterial-induced thrombosis remains one of the main complications of vascular implant devices. Preadsorbed proteins on the biomaterial/blood interface will modify the adhesion and activation of platelets (PTLs) during the initial contact-phase. Our results clearly show that PTL-adherence on biomaterials is influenced not only by protein preadsorption, but also by flow conditions. The covalent coating of TCPS and glass by phosphorylcholine (PC) induces a significant decrease of PTL adhesion but leads to a slight, but nevertheless significant activation of PTL, which was detected by the induction of P-selectin expression using FACS analysis. Methodologically, the visualization of PTL adhesion gave more reliable results for measurement of PTL adhesion than the cell-enzyme immunoassay (EIA) for P-selectin. Human citrated plasma caused an inhibition of PTL. It is probable, that the contained sodium citrate may inhibit PTL adhesion by its calcium ion-binding capacity. The flow experiment as dynamic system is in our view absolutely essential for the evaluation of biomaterials for vascular prosthesis, and is in accordance with the international standards. The results of the experiments also suggest that investigations under static and flow conditions are needed to determine the influence of protein adsorption on mixed blood cell populations, for example, on PTL and PMN mixtures/co-cultures in order to achieve a better simulation of the in vivo situation. 相似文献
83.
The stray radiation field outside the shielding of high-energy accelerators comprises neutrons, photons and charged particles with a wide range of energies. Often, accelerators operate by accelerating and ejecting short pulses of particles, creating an analogue, pulsed radiation field. The pulses can be as short as 10 micros with high instantaneous fluence rates and dose rates. Measurements of average dose equivalent (rate) for radiation protection purposes in these fields present a challenge for instrumentation. The performance of three instruments (i.e. a recombination chamber, the Sievert Instrument and a HANDI-TEPC) measuring total dose equivalent is compared in a high-energy reference radiation field (CERF) and a strongly pulsed, high-energy radiation field at the CERN proton synchrotron (PS). 相似文献
84.
Klement Möhler Otto Mayrhofer Raul Pires und Siegfried Looser 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1967,134(1):19-20
Ohne ZusammenfassungTeil einer Dissertationsarbeit vonR. Pires. Techn. Universität München. 相似文献
85.
86.
An experimental assembly incorporating a capacitance-type, differential pressure transducer, which provides resolutions of 3 × 10?4 torr at pressures extending to 30 torr, has been employed to monitor the effect of hydrogen environmental pressure on the hydrogen yield from x-irradiated polyethylenes. Contrary to the observations of previous investigators, the hydrogen yield is found to be independent of hydrogen environmental pressures extending over the critical range up to at least 30 torr. It is demonstrated that neglecting the temperature and density gradients inherent in closed-volume irradiation assemblies employing cryogenic traps to separate liberated gases into condensable and noncondensable fractions may lead to erroneous conclusions with respect to gas yields arising from the irradiation of materials. A homogeneous, variable-plate separation ion chamber consisting of a polyethylene body and utilizing flowing ethylene as the cavity gas was employed to obtain total volatile G values of 3.6 ± 0.4, 3.8 ± 0.4, and 4.0 ± 0.4 molecules/100 e.v., for Marlex 6002, Dow Ziegler (Q 917.5), and DuPont A-1410 polyethylenes, respectively. A hydrogen contribution of approximately 98 mole-% was obtained with this experimental method. 相似文献
87.
A multi-criteria assessment tool for screening preliminary product platform concepts 总被引:2,自引:0,他引:2
Platform concept evaluation is a more challenging task than evaluating a single product concept since a platform must effectively
support multiple product variants over a prolonged period of time. Existing platform methods develop specific criteria in
depth, yet an evaluation of alternative platforms should be based on a broad set of criteria. Based on expert interviews,
personal experience, and a literature search we propose a platform assessment tool consisting of 19 criteria for platform
evaluation. The criteria are group into six categories: customer satisfaction, variety, after-sale, organization, flexibility,
and complexity. The tool is focused on the early platform architecture phase, before proof-of-concept prototyping. However,
it can also be used subsequently for platform refinement when more data becomes available. We demonstrate our platform assessment
tool through an example with a cordless drill platform. 相似文献
88.
Packaged enterprise software, in contrast with custom-built software, is a ready-made mass product aimed at generic customer groups in a variety of industries and geographical areas. The implementation of packaged software usually leads to a phase of appropriation and customization. As the associated processes remain ill understood, particularly for multi-site implementations, the objective of this paper is to understand the impact of packaged software in a multi-site organization. Adopting a case study method, this paper reports on a multi-site project that was analyzed at the group, site, and corporate level. Our findings suggest that as organizational units face the unsettling experience of having to implement a single source code across globally distributed sites, packaged software intensifies organizing and learning processes across these levels. The paper identifies specific processes for these levels and concludes with implications for research and practice. Our research extends IS research on packaged software implementation with an emphasis on multi-site firms. 相似文献
89.
90.
The main benefit, the economical manufacturability of traditional gear profiles, such as an involute, are no longer of major importance in times of computer-aided design and production. Due to existing modern production techniques standard and more sophisticated gear types can be produced with high precision and maintainable financial effort. Especially for non-standard gear types modern gear production systems ensure high quality and reliability to the operator with regard to flank and meshing geometry. Depending on the context of application different gear types have advantages and disadvantages concerning load carrying capacity, effectiveness or noise excitation. Developing an optimized gearing for the desired application is thus a complex and elementary goal within the design process. 相似文献