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51.
52.
Identification of the tyrosine protein kinase from LSTRA cells by use of site-specific antibodies. 总被引:7,自引:2,他引:7 下载免费PDF全文
J E Casnellie L E Gentry L R Rohrschneider E G Krebs 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(21):6676-6680
The lymphoma cell line LSTRA contains an elevated level of tyrosine protein kinase activity. It has been suggested that this elevated level of activity is due to the presence of a phosphoprotein with a molecular weight of 56,000 (pp56, formerly referred to as a 58,000-dalton protein). This paper describes the preparation of antibodies against pp56 through the use of a synthetic peptide that contains the sequence around the site of tyrosine phosphorylation in pp56, which is identical to the phosphorylation site in pp60src. These antipeptide antibodies specifically immunoprecipitated 32P-labeled pp56 from detergent extracts of LSTRA cells. In immunoblotting experiments, pp56 was the major antigen detected in the particulate fraction from LSTRA cells by the antipeptide antibodies. The antibodies were also used to show that the level of pp56 is greatly elevated in LSTRA cells. Incubation of the detergent extract of the particulate fraction from LSTRA cells with the antipeptide antibodies resulted in inhibition of most of the LSTRA cell tyrosine protein kinase activity. These results indicate that pp56 is the tyrosine protein kinase whose activity is elevated in LSTRA cells. This enzyme may be a member of the large family of protein kinases involved in the regulation of cell growth. 相似文献
53.
Edler C. Krebs O. Gehl A. Palatzke K. Tiedemann N. Schröder A. S. Klein A. 《International journal of legal medicine》2020,134(3):921-927
International Journal of Legal Medicine - Blood at crime scenes is one of the most significant traces of evidence in investigation proceedings. Cleaning up these traces with household cleaning... 相似文献
54.
Thomas Krebs Michael Boettcher Hansjörg Schäfer Georg Eschenburg Katharina Wenke Birgit Appl Beate Roth Thomas Andreas Carla Schmitz Rebecca Fahje Birthe Jacobsen Bastian Tiemann Konrad Reinshagen Kurt Hecher Robert Bergholz 《Surgical endoscopy》2014,28(8):2437-2442
Background
The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model.Methods
Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used.Results
In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls.Conclusions
Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation. 相似文献55.
The avian hippocampal formation (HP) is considered to be homologous to the mammalian hippocampus, being involved in memory formation and spatial memory in particular. The subdivisions and boundaries of the pigeon hippocampus have been defined previously by various morphological methods to detect further similarities with the mammalian homologue. We studied the efferent projections of the zebra finch hippocampus by applying Phaseolus vulgaris leucoagglutinin, and three main subdivisions were distinguished on the basis of the connectivity patterns. Dorsolateral injections gave rise to projections innervating the rostralmost extension of the HP, a laminar complex including the dorsal and ventral hyperstriata and the lamina frontalis superior, the rostral lobus parolfactorius, the medial and ventral paleostriatal regions, the lateral septal nucleus, the nucleus of the diagonal band, the dorsolateral corticoid area, the archistriatum posterius, and the nucleus taeniae in the telencephalon. In the diencephalon, labelled axons were seen in the periventricular and lateral hypothalamus, including the lateral mammillary nuclei, and in the dorsolateral and the dorsomedial posterior thalamic nuclei, whereas, in the midbrain, only the area ventralis of Tsai contained hippocampal fibres. With the exception of the bilateral archistriatal efferents, all projections were ipsilateral. Dorsomedial injections gave rise to a local fibre system that was almost completely restricted to the ipsilateral hippocampal formation. In addition, lectin-containing fibres continued in the dorsal septal region and a thin band in the hyperstriatum accessorium, adjacent to the lateral ventricle. Ventral injections gave rise to axons innervating the dorsolateral subdivision ipsilaterally and bilaterally the medial septal nuclei and the contralateral ventral hippocampus. © 1996 Wiley-Liss, Inc. 相似文献
56.
Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed. 相似文献
57.
OBJECTIVE: Few studies exist on gait adaptation caused by knee osteoarthritis (OA), and those have only explored adaptations of the kinematics and kinetics of the knee joint itself. We characterize ankle, knee, hip, and low back mechanical energy expenditures (MEE) and compensations (MEC) during gait in patients with knee OA. METHODS: Thirteen elderly patients with unilateral knee OA and 10 matched healthy elderly controls were studied during preferred and paced speed gait. Gait speed, step length, and lower extremity and low back joint MEE and MEC were compared between groups. RESULTS: Patients with knee OA had lower, but not significantly different, walking speed and step length compared to the controls, and had significantly different joint kinetic profiles. Patients had reduced ankle power at terminal stance, lacked a second positive peak in knee power, and had increased power absorption at the hip. Abnormal knee kinematics were exaggerated when walking at a paced speed, but hip kinetics normalized among patients with OA. CONCLUSION: Reduced ankle plantar-flexion power in patients with knee OA was probably due to disrupted transfer of energy through the knee. Lack of concentric knee power supports prior studies' conclusions that patients with knee OA avoid using their quadriceps to stabilize the knee, probably to reduce articular loads. Patients with knee OA increase eccentric hip power due to increased hip extension caused by abnormal knee kinematics, potentially increasing hip articular forces. This passive mechanism, however, may assist in the advancement of the leg into swing phase. 相似文献
58.
Stimulation of protein phosphatase activity by insulin and growth factors in 3T3 cells. 总被引:8,自引:1,他引:8 下载免费PDF全文
C P Chan S J McNall E G Krebs E H Fischer 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(17):6257-6261
Incubation of Swiss mouse 3T3-D1 cells with physiological concentrations of insulin resulted in a rapid and transient activation of protein phosphatase activity as measured by using [32P]phosphorylase a as substrate. Activation reached a maximum level (140% of control value) within 5 min of addition and returned to control levels within 20 min. The effect of insulin was dose-dependent with half-maximal activation occurring at approximately 5 nM insulin. This activity could be completely inhibited by addition of the heat-stable protein inhibitor 2, which suggests the presence of an activated type-1 phosphatase. Similar effects on phosphatase activity were seen when epidermal growth factor and platelet-derived growth factor were tested. These results suggest that some of the intracellular effects caused by insulin and growth factors are mediated through the activation of a protein phosphatase. 相似文献
59.
Ohne Zusammenfassung 相似文献
60.
Kurt Kroenke Samantha Outcalt Erin Krebs Matthew J. Bair Jingwei Wu Neale Chumbler Zhangsheng Yu 《General hospital psychiatry》2013