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31.
32.
Djurdjica Masic Reiner Hamm und Luise Tetzlaff 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1971,146(4):205-211
Zusammenfassung Im Gewebeextrakt und Preßsaft der Brust- und Schenkelmuskulatur des Huhns sowie der Brustmuskulatur von Pute, Gans, Ente und Taube wurde die Aktivität der Aspartat-Aminotransferase (GOT; E.C.2.6.1.1.) und der Alanin-Aminotransferase (GPT; E.C.2.6.1.2.) bestimmt. Die Gesamt-GOT-und GPT-Aktivität war in der dunklen Schenkelmuskulatur des Huhnes signifikant höher als in der hellen Brustmuskulatur. Eine ähnliche Beziehung zwischen Myoglobingehalt und Transaminase-Aktivität bestand auch bei den anderen Geflügelarten. Hühner- und Putenmuskeln wiesen die niedrigsten, Taubenmuskeln die höchsten Transaminase-Aktivitäten auf. Die gesamte GPT-Aktivität in den Muskeln von Huhn und Pute betrug etwa ein Hundertstel der gesamten GOT-Aktivität; in den Muskeln der übrigen Geflügelarten machte die GPT-Aktivität etwa ein Zehntel der GOT-Aktivität aus.In der Muskulatur aller untersuchten Geflügelarten ließen sich durch Elektrophorese zwei GOT-Isozyme nachweisen. Ein Isozym (GOT
S
) befand sich im Sarkoplasma, das andere Isozym (GOT
M
) war in den Mitochondrien lokalisiert. Die GOT
M
-Aktivität in Brust- und Schenkelmuskel des Huhns betrug durchschnittlich 65% der gesamten GOT-Aktivität. Bei den übrigen Geflügelarten schien mit steigendem Myoglobingehalt des Brustmuskels die relative GOT
M
-Aktivität zuzunehmen.Während siebentägiger postmortaler Lagerung von Brust- und Schenkelmuskulatur des Huhns bei 4° C trat keine wesentliche Änderung der gesamten GOT-Aktivität ein. Die niedrige relative GOT
M
-Aktivität im Muskelpreßsaft nahm während der Lagerung des Muskels nur wenig zu; eine Schädigung der Mitochondrienmembranen tritt daher während der Reifung von Hühnerfleisch nicht ein.
Fräulein H. Sauer danken wir für ihre fleißige und gewissenhafte Mitarbeit. 相似文献
Aminotransferases in the skeletal muscles of poultry
Summary The activity of aspartate aminotransferase (GOT; E.C.2.6.1.1.) and alanine amino-transferase (GPT; E.C.2.6.1.2.) in the breast and thigh muscle of chicken and in the breast muscle of turkey, goose, duck, and pigeon was determined. The total GOT and GPT activity of the red thigh muscle of chicken was significantly higher than that of the white breast muscle. A similar relation between myoglobin content and transaminase activity in breast muscle was found for the other species of poultry. Chicken and turkey muscles showed the lowest, pigeon muscles the highest transaminase activities. The total GPT activity of chicken and turkey muscles was about one-hundredth of the total GOT activity; the GPT activity in muscles of the other species was about one-tenth of the total GOT activity.In the extract of the muscles of all species two GOT isozymes could be demonstrated after electrophoretic separation. One isozyme (GOT M ) is localized within the mitochondria, the other isozym (GOTs) was found in the sarcoplasma. About 65% of the total GOT activity in breast and thigh muscles of chicken was due to the activity of the mitochondrial isozyme. In the breast muscles of the other species, higher relative GOT M activity was found in the muscles with high myoglobin content than in those with low myoglobin content.There was no remarkable change in the total GOT activity of the muscle extract during storage of chicken breast and thigh muscles at +4° C for seven days post mortem. The small relative GOT M activity of the muscle press juice remained almost unchanged during post-mortem storage of muscle tissue indicating that there is no desintegration of the mitochondrial membranes during aging of chicken meat.
Fräulein H. Sauer danken wir für ihre fleißige und gewissenhafte Mitarbeit. 相似文献
33.
Fanucci L. Letta E. de Daudenzi R. Giannetti F. Luise M. 《Selected Areas in Communications, IEEE Journal on》2001,19(2):179-190
This paper presents the design and the main performance results of a single-ASIC implementation of the recently proposed extended complex-valued blind anchored interference-mitigating detector (EC-BAID) for code division multiple access (CDMA) transmission. Such a detector, which exhibits a remarkable robustness to multiple access interference, operates in blind mode, i.e., it only requires knowledge of the timing of the wanted user's signature code, and it is therefore very well-suited for integration into handheld single-user terminal demodulators. The implementation of the interference-mitigating detector is based on a patented optimized architecture which leads, in 0.25-μm CMOS technology, to a roughly 25 Kgate plus 23-Kbit RAM single-chip ASIC supporting chip rates up to 4 Mchip/s with a maximum internal clock frequency of 32.768 MHz. The main design drivers are thoroughly discussed, and the relevant performance results are compared to the theoretical behavior. A possible extension to multirate CDMA systems adopting orthogonal variable spreading factor (OVSF) sequences is also addressed 相似文献
34.
G. Meneghesso R. Luise D. Buttari A. Chini H. Yokoyama T. Suemitsu E. Zanoni 《Microelectronics Reliability》2000,40(8-10)
A study of InP based HEMTs implemented with different process options will be reported. It will be demonstrated that devices with an InP etch stopper layer or with a narrow lateral gate recess region do not present any kink effect, neither any transconductance frequency dispersion, gm(f) and a stable behavior with respect to hot electron aging is observed. The opposite occurs in devices without the InP etch stopper layer and a wide lateral gate recess region. The data presented confirm the effectiveness of an InP passivating layer in improving the reliability of advanced InP-HEMTs, and point out at the free InAlAs surface as responsible for the observed instabilities (kink effects, gm(f) dispersion). 相似文献
35.
Karin Hoppert Susann Zahn Luise Jänecke Robert Mai Stefan Hoffmann Harald Rohm 《International Dairy Journal》2013,28(1):1-7
Reduction of energy in foods by eliminating sugar, combined with an increase in fiber, frequently results in products with sensory characteristics that cannot be compared with standard counterparts. This study analyzed the response of young educated consumers (n = 704) on standard or reduced-sugar vanilla yogurt enriched with inulin or with inulin combined with a grain mixture, a milled mixture of flakes, or a combination of grains and milled flakes. On a nine-point hedonic scale, mean acceptance was 6.4 and 6.8 for yogurt with 112 g kg?1 and 160 g kg?1 sugar, respectively. It was concluded from acceptance data and from results obtained by just-about-right rating that adapting the flavoring concentration might be an appropriate tool to mask sugar reduction. In yogurt with visible fiber, it is mainly the size of incorporated fiber that should be considered in product optimization. In these products, sugar content significantly affects acceptance. 相似文献
36.
De Gaudenzi R. Garde T. Giannetti F. Luise M. 《Selected Areas in Communications, IEEE Journal on》1995,13(2):325-332
In recent years, code division multiple-access (CDMA) techniques have received a great deal of attention for mobile terrestrial/satellite communication systems. Primarily considered for the noteworthy features of low power flux density emission and robustness to interference and multipath, CDMA is known to bear reduced bandwidth and power efficiency when compared to traditional TDMA and FDMA due to the intrinsic cochannel self-noise. Early attempts to increase the capacity of CDMA-based systems for commercial applications relied on voice activation and frequency reuse. More recently, practical solutions to implement (synchronous) orthogonal CDMA signaling are being developed independently in Europe and in the USA. This paper is focused on the comparative performance analysis of those two orthogonal CDMA schemes in the operating renditions of a mobile satellite communications system. In particular, the two CDMA systems are compared in the presence of that and frequency-selective multipath fading and a typical satellite transponder nonlinearity. Most numerical results are derived through a time-domain system simulation that confirms and integrates the theoretical findings 相似文献
37.
M. Luise R. Reggiannini G. M. Vitetta 《International Journal of Satellite Communications and Networking》1992,10(6):325-342
In this paper we address the design of the data demodulator for high-efficiency satellite communications suited for telemetry applications. We choose Gaussian minimum shift keying as the modulation format and analyse its relative merits with respect to the more traditional filtered offset quadrature phase-shift keying scheme, when applied to medium-to-high data rate telemetry. Our study encompasses both geostationary orbits and the more challenging low earth orbit scenarios, and investigates the acquisition and tracking performance of the receiver with the aid of computer simulations. In particular, we present design criteria leading to the development of efficient, low-complexity schemes for symbol timing and carrier phase/frequency recovery and we analyse the impact of these synchronization algorithms on the system performance. Next, we discuss the demodulator performance degradation when the transmitted signal is passed through on-board solid-state or travelling-wave-tube power amplifiers. The paper is concluded by a comparative analysis of the above modulation schemes, with special emphasis on their power and spectral efficiency. 相似文献
38.
39.
Richard Degenhardt Alexander Kling Arne Bethge Jana Orf Luise Kärger Rolf Zimmermann Klaus Rohwer Adriano Calvi 《Composite Structures》2010
In the field of aerospace engineering but also in the fields of civil and mechanical engineering the industry demands for significantly reduced costs for development and operating. Reduction of structural weight at safe design is one avenue to achieve this objective. In many cases it results in thin-walled structures, which are prone to buckling if subjected to compression or shear. The presented paper is based on a recent European Space Agency (ESA) study, conducted at DLR Braunschweig, on Probabilistic Aspects of Buckling Knock-Down Factors and contributes to this goal by striving for an improved buckling knock-down factor (the ratio of buckling loads of imperfect and perfect structures) for unstiffened CFRP cylindrical shells. Buckling tests and buckling simulations were performed to investigate the imperfection sensitivity and to validate the applied simulation methodologies. Test results as well as deterministic and probabilistic buckling simulation results are presented and compared. Finally, improved knock-down factors are deduced and discussed. 相似文献
40.
Eberhard RITZ Ralf DIKOW Marie‐Luise GROSS 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z1):S2-S11
Atherosclerosis, particularly coronary atherosclerosis, is accelerated in renal failure, as originally postulated by Belding Scribner. But in contrast to previous opinion, myocardial infarction from coronary heart disease is not the single major cause of cardiac death in dialyzed patients, the most common causes being sudden death and cardiac failure. Apart from coronary heart disease, the following cardiomyopathic features are prevalent and explain a large part of the excess cardiac risk: cardiomyocyte dropout, left ventricular hypertrophy, cardiac interstitial fibrosis, microangiopathy with arteriolar thickening, and capillary deficit as well as reduced ischemia tolerance. Recently, cardiovascular risk factors related to abnormal mineral metabolism, particularly phosphate and vitamin D, have gained unanticipated importance. Controlled evidence has become available concerning intervention with ACE inhibitors, angiotensin receptor blockers, β‐blockers, and statins in dialyzed patients. It is imperative that apart from the “classical” cardiovascular risk factors that do not exhaustively explain the excessive cardiovascular risk in dialyzed patients, novel pathomechanisms are considered and investigated; potential examples include depression, sleep abnormalities, etc. The above arguments do not negate the fact that today's modalities of renal replacement therapy are poor substitutes for the normal kidney's function so that as a result alternative strategies, e.g., daily dialysis, may also dramatically improve cardiovascular risk. 相似文献