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191.
A 2.3 kb region of rabbit cardiac and skeletal muscle titin has been cloned. The cDNA sequences of the two tissues are identical and show 91% identity on the nucleotide level with the corresponding region of human cardiac muscle titin. On the amino acid level the identity is 96% and similarity is 98%. Alignment of predicted amino acid sequences of several homologous kinase domains reveals that the rabbit titin kinase has all the necessary elements of an active catalytic domain and carries a potential regulatory region on its C-terminal end. The distance of the 2.3 kb contig from the 3' end of the message was determined to be 5.7 kb in both tissues using oligonucleotide directed RNase H cleavage of titin mRNAs. This is essentially identical with the length of the fully sequenced human cardiac titin C-terminal end. It therefore appears unlikely that there are major tissue specific differences in this 8 kb cDNA region which encodes the C-terminus of rabbit skeletal and cardiac titin. 相似文献
192.
E. Fritz 《Journal of the American Oil Chemists' Society》1979,56(11):744A-746A
Examples are presented of the effect of each processing step on the quality, yield and throughput in the fatty acid processing
scheme. These examples serve to illustrate the importance of seemingly unimportant process variables upon the economic involved
in fatty acid processing. 相似文献
193.
194.
195.
196.
Cook Larry T. Cook P. Nong Rak Lee Kyo Batnitzky Solomon Wong Bert Y. S. Fritz Steven L. Ophir Jonathan Dwyer Samuel J. Bigongiari Lawrence R. Templeton Arch W. 《IEEE transactions on bio-medical engineering》1980,(9):493-500
A volume algorithm is established which uses the data generated by computed tomography (CT) or ultrasound scans. The algorithm is based on a polyhedral reconstruction of an object of interest. Phantom studies indicate that the algorithm calculated volume is accurate within 3 percent. In a controlled clinical experiment on a laboratory animal, the algorithm calculated volume showed a maximum error of about 5 percent. In less controllable applications to human clinical data, volume calculations showed variations ranging up to 16 percent. 相似文献
197.
Intermittent electrical stimulation of the lateral hypothalamus of rats performed for 30 min to 6 hr, results in hyperlipidemia
and endothelial cell damage of the aorta and coronary arteries. Hyperlipidemia is related to transient biliary obstruction
elicited by hypothalamic stimulation and is characterized by elevation of the cholesterol, phospholipid, and triglyceride
fractions. Endothelial cell damage is observed ultrastructurally as plasma membrane degeneration with detachment and the formation
of large spaces (“vacuoles”). Thus, neural factors may be implicated in inducing conditions associated with early atherogenesis.
Stimulation carried out for longer time intervals would be expected to produce more advanced lesions. However, the role of
neural transmission per se (i.e., without hyperlipidemia) in producing arteriopathy is not clearly defined from these experiments.
In rats, the lesser splanchnic nerve forms the major innervation of the abdominal aorta. In animals fed normal diets, chronic
intermittent stimulation of this nerve (up to 3 weeks) resulted in advanced arteriosclerotic changes with intimal fibrosis
and calcification. On histologic examination, lipid deposits appeared to be absent from these lesions. Animals stimulated
for shorter periods of time exhibited earlier changes associated with atherogenesis, such as endothelial damage, elastic reduplication,
and adherent microthrombi. Thus, direct neural transmission, especially if excessive, plays a role in producing arteriopathy.
Hyperlipidemia, if persistent, could modify these lesions so that they would accumulate plasma lipids. Experiments to test
this hypothesis are currently in progress. 相似文献
198.
Klement Mohler und Fritz Niermann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1974,156(1):1-8
Zusammenfassung Die Farbreaktion von Pyrrol mitp-Dimethylaminobenzaldehyd ist als Ehrlichsche Reaktion die Grundlage der Hydroxyprolin-Bestimmung nach Oxydation mit Wasserstoffperoxid. Nach eingehender Untersuchung des Oxydationsverlaufes wurden die Reaktionsbedingungen der Farbbildung geprfift, die nicht quantitativ abläuft, sondern einem Gleichgewicht zustrebt.
Determination of hydroxyproline in foods
Summary The determination of hydroxyproline after oxydation with hydrogenperoxide bases on the reaction of pyrrol with p-dimethylaminobenzaldehyde (Ehrlich-reaction). The oxydation and colour formation was tested and it was shown that finally there is no quantitative reaction but an equilibrium, which is reached.相似文献
199.
An acht Magnesitsteinen mit unterschiedlichem Magnesiumoxyd- (88,5 bis 92,5 und rd. 96%) und Flußmittelgehalt Untersuchung der physikalischen Eigenschaften (spezifisches Gewicht, Raumgewicht, Porigkeit usw.), der thermischen Ausdehnung und der Druckfeuerbeständigkeit sowie des Dauerstandverhaltens bis zu einer Belastungsdauer von 24 h. 相似文献
200.
Lust S Vanhoecke B Janssens A Philippe J Bracke M Offner F 《Molecular nutrition & food research》2005,49(9):844-850
B-chronic lymphocytic leukemia (B-CLL) is an indolent lymphoid malignancy with variable prognosis. Adverse prognostic factors comprise treatment resistance, cytogenetics (11q- and 17p-), the presence of unmutated Ig genes, and the more comprehensive activation marker Zap 70. In contrast to diminished sensitivity to chemotherapy, Zap 70+ B-CLL cells retain their responsiveness to manipulation of signal transduction and monoclonals. Xanthohumol (XA) has recently been documented to have an impact on breast cancer cell growth and invasiveness in vitro. Based on these observations, lymphocytes from patients with B-CLL were cultured in the presence of XA in vitro. XA induced a dose-dependent killing of B-CLL cells at an LD(50) ((24 h)) of 24.4 +/- 6.6 microM, independent of known adverse prognostic factors including functional loss of p53. Cell death was associated with poly (ADP)-ribose polymerase cleavage and annexin V positivity, suggestive of an apoptotic mechanism. Surprisingly, p 70(S 6 K) phosphorylation was stimulated upon XA treatment. In conclusion, XA has an antitumor activity on B-CLL cells in vitro. The molecular mechanisms behind this pro-apoptotic effect deserve further investigation. 相似文献