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31.
Rechtsanwalt Professor Dr. iur. Karl Otto Bergmann Rechtsanwältin Dr. iur. Carolin Wever 《MedR Medizinrecht》2007,25(8):475-476
Ohne Zusammenfassung 相似文献
32.
Rechtsanwalt Professor Dr. iur. Karl Otto Bergmann Rechtsanwältin Dr. iur. Carolin Wever 《MedR Medizinrecht》2007,25(11):649-650
Ohne Zusammenfassung 相似文献
33.
34.
Activity-dependent facilitation is a mechanism of associative synaptic plasticity that contributes to classical conditioning in Aplysia. Previous studies of activity-dependent facilitation in the mechanosensory neurons of Aplysia suggested that the Ca2+ influx during paired spike activity enhances the transmitter-stimulated, cAMP-dependent, presynaptic facilitation in these cells. Moreover, paired activity was found to potentiate the activation of the adenylate cyclase by transmitter. It was therefore proposed that the Ca2+/calmodulin-sensitive cyclase may serve as a site of interaction between the inputs from the conditioned and unconditioned stimuli. These studies were carried out to test whether a Ca2+/calmodulin-sensitive adenylate cyclase in the Aplysia CNS has the properties necessary to mediate such an associative interaction. Three lines of evidence indicate that the same cyclase molecules that are sensitive to Ca2+/calmodulin are also stimulated by receptor to facilitatory transmitter via the stimulatory G-protein, Gs: First, calmodulin inhibitors reduced stimulation of the cyclase by facilitatory transmitter. When membranes had been preexposed to one of these inhibitors, trifluoperazine, the addition of exogenous calmodulin partially reversed the inhibition. Second, when Gs had been activated by GTP gamma S, so that it persistently activated the catalytic unit of the cyclase, stimulation of the cyclase by Ca2+ was greatly amplified, suggesting that the two inputs interact in activating a common population of the enzyme. Third, solubilized cyclase activity that bound to calmodulin-Sepharose in a Ca(2+)-dependent manner was stimulated by Gs, which had been partially purified from Aplysia CNS, as well as by Ca2+/calmodulin. Having demonstrated dual activation of the cyclase, we have explored the dependence of cyclase activation on the temporal pattern of Ca2+ and transmitter addition. Optimal activation required that a pulse of Ca2+ temporally overlap the addition of facilitatory transmitter. These several results suggested that the dually regulated adenylate cyclase might underlie the temporal requirements for effective classical conditioning in this system. 相似文献
35.
Karl Lehner M.D. Maximilian Reiser Ulrich Gebhardt Andreas Heuck Jürgen Schaff 《Cardiovascular and interventional radiology》1987,10(2):71-74
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized
by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic
agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining
aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific
details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only. 相似文献
36.
37.
HLA-DR7 predicts the response to alkylating agents in steroid-sensitive nephrotic syndrome 总被引:2,自引:0,他引:2
Martin Konrad Joannis Mytilineos Hans Ruder Gerhard Opelz Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):16-19
There is a lack of reliable predictors of the response to alkylating agents in children with idiopathic nephrotic syndrome
(NS). HLA-DR7 is strongly associated with the frequency of relapses in steroid-sensitive NS before cytostatic therapy. We
therefore examined retrospectively the time to the first relapse and the incidence of subsequent relapses in 54 HLA-typed
children with frequently relapsing NS, after treatment with cyclophosphamide (n = 49) or chlorambucil (n = 5) for 8 or 12 weeks; 38 patients were HLA-DR7 positive and 16 negative with 80% in both groups being steroid dependent.
HLA typing was performed using serological or DNA typing methods. Renal biopsy showed minimal glomerular changes. A lower
proportion of HLA-DR7 positive than negative patients remained in remission after 3 years (36% vs. 81%, P<0.02) and 5 years (36% vs. 72%, P<0.03). In the first 3 years after cytostatic therapy the mean number of prednisone-treated relapses was 1.3/patient per year
in HLA-DR7-positive patients compared with 0.4 in negative patients (P<0.025). There was no statistically significant difference in the proportion of relapse-free patients with and without steroid
dependency. The HLA status predicts the response of NS patients to alkylating agents better than the rate of previous relapses.
Received September 19, 1995; received in revised form and accepted April 16, 1996 相似文献
38.
39.
A new look at grief 总被引:1,自引:0,他引:1
George T. Karl MDIV MA 《Journal of advanced nursing》1987,12(5):641-645
40.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献