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41.
The catechol-O-methyltransferase (COMT) Val158Met polymorphism modulates executive functions and working memory and recent neuroimaging studies implicate an association with emotional processing. We examined the relationship between the COMT Val158Met polymorphism and facial emotion recognition and differentiation in 100 healthy individuals. Compared to Met homozygosity, Val homozygosity was associated with better and faster recognition of negative facial expressions such as anger and sad. Our study provides evidence for a possible influence of the COMT polymorphism on emotion recognition abilities in healthy subjects. Additional research is needed to further define the neurocognitive phenotypes associated with COMT polymorphisms.  相似文献   
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OBJECTIVE: We have previously shown that fixed pulmonary hypertension in cardiac transplant candidates can be lowered using left ventricular assist devices (LVADs). The post-transplant survival of these patients is uncertain as pulmonary hypertension may reappear, possibly affecting post-transplant survival. MATERIALS AND METHODS: Between 01/2000 and 01/2005 a total of 26 cardiac transplant candidates (92% male; mean age 56.2 years) in whom fixed pulmonary hypertension was lowered by LVAD implantation (pulmonary vascular resistance (PVR) before implantation: 5.1+/-2.8wood units (WU); PVR before cardiac transplantation: 2.0+/-.9WU) underwent cardiac transplantation at our institution. These patients were age and sex matched with 52 cardiac transplant candidates without pulmonary hypertension undergoing cardiac transplantation during the same time period. Study endpoints were peri-transplant complications and long-term survival. Mean follow-up was 36+/-14 months. RESULTS: Peri-transplant mortality was 5% in patients after LVAD therapy and 7% in patients without prior LVAD therapy (p=.089). We observed 2 cases (4%) of acute right heart failure requiring mechanical support in patients without prior LVAD therapy. None of the patients with LVAD therapy developed peri-transplant right heart failure requiring mechanical support. Incidence of other peri-transplant complications was comparable between the two groups. Log-rank (p=.124) revealed comparable long-term survival between patients with (1 year: 85%, 2 year: 85%, 3 year: 85%) and without (1 year: 90%, 2 year 82%, 3 year prior 79%) prior LVAD therapy. CONCLUSION: LVAD therapy lowers fixed pulmonary hypertension in cardiac transplant candidates with fixed pulmonary hypertension. Thereafter, long-term post-transplant survival is comparable to cardiac transplant recipients without pulmonary hypertension.  相似文献   
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The beating heart and the resultant pulse wave have been a symbol of life for centuries. The development history of roller pumps for cardiopulmonary bypass shows that the human body tolerates non-pulsatile blood flow, at least for short-term support. Over the last few years, many types of rotary blood pumps have been developed for clinical use in patients requiring mid- to long-term support. Although early clinical experiences in patients with long-term support have been promising, the matter of whether pulsatile flow is needed or not remains controversial. Therefore, this review summarizes the observed clinical consequences of continuous blood flow in patients supported by rotary blood pumps and relates these consequences to underlying experimental studies.  相似文献   
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Pumice has been used as a serviceable abrasive or religious artefact since antiquity and has therefore been an object of trade. It can be found in excavations of ancient workshops all over the Mediterranean.Pumice lumps from the major pumice-bearing rhyolitic tephra units in Cappadocia—the Central Anatolian Volcanic Province, Turkey (in particular the ignimbrites Kavak, Çemilköy, Tahar, Gördeles, and the volcanic complexes of Acıgöl and Hasan Dağı), were sampled and analyzed for major and trace element concentrations using instrumental neutron activation analysis (INAA). Elements determined were Na, K, Sc, Cr, Fe, Co, Zn, As, Rb, Zr, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Ta, Th, and U.Since the distribution of those elements is characteristic of the products of a certain eruption, this “chemical fingerprint” can be used to establish the origin of an unknown pumice sample by comparison with samples of known origin. In the course of this study, it could be shown that one pumice finding from the excavation in Miletos (Turkey) probably originates from the Hasan Dağı volcanic complex in Cappadocia. Since it is known that the population in Miletos focused their trade connections on the Mediterranean, this result is somewhat surprising.Two other samples from Miletos show a very high similarity to the chemical fingerprint of pumice from the Kos Plateau Tuff (KPT; Greece): In one case, the identification is doubtless, in the other case identification as KPT seems quite probable.  相似文献   
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PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo.  相似文献   
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Ohne ZusammenfassungMit 10 Abbildungen im Text.Die Arbeit wurde ausgeführt mit Unterstützung der Lady Tata Memorial-Stiftung, der wir für die Ermöglichung unserer Arbeiten zu größtem Danke verpflichtet sind.  相似文献   
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