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141.
142.
Prof. Dr. J. Neuzner S. Willems H.U. Klein M. Block 《Herzschrittmachertherapie & Elektrophysiologie》2010,21(3):186-188
Increasing workloads, growing economical pressure and developments on the German job market for young physicians create a background which threatens an adequate education and training of physicians in many places. The“Fellowship heart rhythm” program focuses on training in clinical electrophysiology complementary to established educational initiatives, such as courses for competence in pacemaker and ICD therapy of the German Cardiac Society. Participants have to be residents with a minimum of 3 years clinical experience and should be younger than 36 years old. They should be actively involved with a long-term perspective in clinical electrophysiology. Activity in the fields of pacing, defibrillator and cardiac resynchronization therapy is required. The hospital has to be able provide the possibility of invasive electrophysiology and catheter ablation including a 3-dimensional mapping system. In 6 face-to-face meetings of 3 days each, the state of the art is presented in the topics electrophysiological studies, sudden cardiac death and defibrillation, health economy/management, catheter ablation, atrial fibrillation and heart failure and arrhythmias. The first 4 years with 2 fellowship programs have demonstrated that this project enables education at a high level, strongly supporting advances in scientific interest, individual development and medical orientation. The fellowship program facilitates the development of a network of young electrophysiologists in Germany. 相似文献
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Andrea Block Maria Rohde Ulrike Erben Markus Hammer Michael Hummel Katja Blunert Heinz-Peter Schultheiss Hans-Dieter Volk Michel Noutsias 《Medical science monitor》2008,14(5):BR88-BR95
BACKGROUND: The effects of different cell culture media on expansion efficiency and alterations in T-cell receptor V beta (TRBV) expression of in vitro expanded lymphocytes are not well established. MATERIAL/METHODS: Low numbers of CD3+ T cells from peripheral blood lymphocytes of healthy donors were subjected to polyclonal in vitro expansion in the presence of autologous CD3-depleted mononuclear cells as feeder cells (FCs) and their numbers and TRBV expressions were compared in media containing human (HS-RPMI) or fetal bovine serum (FBS-RPMI), Panserin413, or X-Vivo 15TM designed for lymphocyte culture. RESULTS: During three courses of restimulation within 28 days with CD3-antibody (OKT-3), IL-2, and initial CD3+, T-cell: FC ratios of 1:50 lowered to 1:5 and T cells expanded more than 1,000-fold in the media containing complete sera. Loss of cluster formation, associated with expansion failure, was only observed in cultures using synthetic media and resulted in only about 70-fold expansion. Whereas TRVB expression as determined by real-time PCR was substantially altered after 14 days of culture in X-Vivo 15, at day 28 only T cells from long-term culture in HS-RPMI presented the initial TRBV composition. CONCLUSIONS: Culture media have substantial impact on in vitro T-cell expansion. In the presence of FCs, medium containing human serum is superior to synthetic media and FBS-RPMI for long-term culture regarding T-cell number and TRBV repertoire. In contrast, the synthetic media Panserin413 and XVivo15 show lower expansion efficiency and reproducibility and, as RPMI1640+10%FBS, can contribute to overstimulation of certain TRBVs at advanced culture time points. 相似文献
145.
Weber KD Fletcher WA Jones GM Block EW 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,135(4):527-534
Previous studies investigated adaptive properties of a podokinetic (PK) system that senses and controls angular movement of the trunk relative to the stance foot when walking around a curved trajectory or during rotational stepping on the spot. In particular, after adaptively modifying the PK system by prolonged stepping-in-place over the axis of a horizontally rotating platform, blind-folded subjects could no longer step in place on firm ground. When trying to do so they invariably rotated themselves relative to space without perceiving their rotation, a phenomenon termed podokinetic after-rotation (PKAR). It is well known that normal rotational stepping generates a specifically podokinetic component of compensatory nystagmus which is independent of the VOR. The present study investigated whether during PKAR this podokinetic component of oculomotor activity follows the somatosensory correlate of actually stepping around, or the cognitive intent or percept of 'no rotation'. Experiments were conducted in two phases on five normal human subjects. In the first phase, the normal passively induced VOR was compared with the combined VOR and PK oculomotor response induced by intentional rotational stepping on the spot. In both cases the angular stimulus was a 2-min rotation at 15 degrees/s. Subtraction of the decaying VOR from the actively induced combined response revealed a constant podokinetic nystagmus with slow-phase velocity gain of about 0.4 maintained throughout this period. The PK and VOR response components appeared to sum linearly. In the second phase, we measured oculomotor activity during PKAR, when the blindfolded subjects involuntarily rotated themselves at around 15 degrees/s while attempting to step-in-place after the podokinetic adaptation procedure noted above. The striking result of the second phase of experiments was that, although an apparently normal decaying VOR was present, the maintained PK component of response was consistently absent, despite an essentially normal physical pattern of rotational stepping. Thus, in the adapted state, non-vestibular oculomotor activity followed the cognitive intent or percept of 'no rotation', rather than the prevailing somatosensory-motor activity of the lower limbs. The finding points to an important cognitive element in this form of oculomotor control. 相似文献
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The hypothesis that central alpha-1 adrenoceptors are inhibitory to the hypotension-induced secretion of vasopressin was tested by subjecting lambs that were instrumented for a long term to varying degrees of hypotension after intracerebroventricular injections of prazosin or placebo. Eight lambs in the 1st wk of life treated with intracerebroventricular injections of placebo had their mean arterial blood pressures decreased 14 and 21% by i.v. infusion of nitroprusside. Arginine vasopressin levels rose to 7.3 +/- 2.4 pmol/L only with the greater degree of hypotension. When the lambs were treated with intracerebroventricular injections of 1 micrograms/kg of prazosin, the blood pressures were decreased 13 and 23%, and the vasopressin levels were 15.4 +/- 16.6 and 27.5 +/- 20.3 pmol/L, respectively. A relationship was shown between the degree of hypotension and the plasma arginine vasopressin levels with both the placebo and prazosin, the slope being much steeper for the prazosin treatment (-1.11) than for the placebo treatment (-0.31). Plasma renin activity was increased a similar amount in both groups, and there was no change in plasma cortisol levels. We conclude that alpha-1 adrenoceptors in the brain are inhibitory to the secretion of arginine vasopressin. These results differ from observations in adult rats and dogs and may be accounted for by developmental or species differences. 相似文献
148.
Cone cerclage in pregnancy 总被引:1,自引:0,他引:1
We report a technique of cone cerclage and the results and outcome in 17 patients who required a diagnostic cone biopsy in pregnancy. The mean age of the patients was 30.6 years (range 21-41). The mean gestational age was 18.8 weeks (range 10-32) at the time of the procedure. There were no major complications and hemorrhage was not a significant problem. There were no second-trimester abortions. Two patients required beta-sympathomimetics to suppress uterine activity for longer than 24 hours after the procedure. Six patients had invasive carcinoma, nine had cervical intraepithelial neoplasia (CIN) III, and two had CIN II. In 14 cases, the endocervical and ectocervical margins were negative; two patients with CIN and one with multifocal microinvasion had positive margins. Cone cerclage is a safe and easy method for performing diagnostic cervical conization during pregnancy. 相似文献
149.
Surgical procedures which involve the pregnant uterus are associated with preterm labor contractions in the postoperative period. Because uterine contractions decrease fetal oxygen tension, we investigated the effect of maternal ritodrine infusion on fetal oxygen consumption in catheterized fetal sheep 5 h postoperatively. During ritodrine infusion, uterine activity promptly abated, but the oxygen tension in the umbilical vein and descending aorta decreased. The arterial-venous oxygen content difference, the umbilical blood flow, and consequently, fetal oxygen consumption did not change significantly. We conclude that fetal oxygenation is not improved by eliminating uterine activity with maternal ritodrine infusion in the postoperative period. 相似文献
150.
BACKGROUND: This research describes tobacco attitudes and practices of health care providers in the Upper Midwest. A baseline measure of preventive practices by providers was needed to plan effective tobacco intervention education programs. METHODS: Health care providers in a 16-county region received a mailed survey regarding tobacco assessment practices, intervention practices, attitudes, skills/knowledge, barriers, and desire for tobacco education. The survey was sent to all chiropractors, dentists, nurse practitioners/physician assistants, physicians (primary care and specialist), and public health nurses in the region. A total of 51.9% (n = 614) of all providers returned usable surveys. RESULTS: Significant differences were found between provider groups on all measured concepts. Primary care physicians, nurse practitioners/physician assistants, and public health nurses were more likely than specialist physicians, dentists, and chiropractors to assess, intervene, be supportive of tobacco cessation, have skills/knowledge about cessation, perceive fewer barriers, and want further education. CONCLUSIONS: In this region, provider groups differed in tobacco use assessment and treatment. All provider groups desired education regarding tobacco intervention. Region-wide tobacco cessation educational initiatives need to take into account differences between provider groups. 相似文献