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61.
K. Racké M. Sommer F. Burns B. Hering 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(4):337-343
Summary Isolated rat pineal glands were incubated in vitro and the release of endogenous noradrenaline or 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) was determined by HPLC with electrochemical detection. In the absence of test drugs, the spontaneous outflow of noradrenaline was about 10 fmol/10 min and electrical stimulation (5 Hz, 1500 pulses) evoked the release of about 70 fmol noradrenaline. Nomifensine enhanced the spontaneous outflow of noradrenaline about threefold and the electrically evoked release of noradrenaline about sixfold. In the presence of nomifensine, the 2-adrenoceptor antagonist yohimbine markedly increased the electrically evoked release of noradrenaline, whereas the 1-adrenoceptor antagonist prazosin had no effect. Clonidine inhibited the electrically evoked release of noradrenaline by about 65%, and this was antagonized by yohimbine in a competitive manner. In the absence of drugs, the initial spontaneous outflow of 5-HT was (compared with noradrenaline) very high 64 mol/10 min. It declined by 80% within 1 h of incubation in vitro. The outflow of 5-HIAA amounted initially to 38 mol/10 min and declined by 40% within 1 h of incubation. Addition of l-tryptophan (10 mol/1) after 1 h of incubation in vitro largely enhanced the outflow of 5-HT and 5-HIAA within 30 min of incubation (about ten- and fourfold, respectively). When l-tryptophan was present from the onset of incubation the initial outflow of 5-HT and 5-HIAA was only slightly elevated, but the decline was largely attenuated. Neither omission of calcium nor addition of nomifensine, clonidine or yohimbine significantly affected the spontaneous outflow of 5-HT or 5-HIAA. Likewise, neither electrical stimulation in the absence or presence of nomifensine and yohimbine nor stimulation by high potassium (45 mmol/1) significantly affected the outflow of 5-HT or 5-HIAA.In conclusion, the release of endogenous noradrenaline from the sympathetic nerves terminating in the pin eal gland is inhibited by presynaptic 2-adrenoceptors. The outflow of 5-HT from the pineal gland originates almost exclusively from non-neuronal cells, most probably the pinealocytes, and depends largely on a continuous de novo synthesis. Catabolism of 5-HT to 5-HIAA in the pineal gland occurs mainly in an extraneuronal compartment, probably the pinealocytes and/or the interstitial cells of the pineal gland.
Send offprint requests to K. Racké at the above address 相似文献
62.
R. A. Blakelock was a highly acclaimed 19th Century visionary American painter who spent 25 years in mental hospitals. Students rated random samples of Blakelock's work completed before, during, and after his breakdown. Paintings completed after the start of his long-term hospitalization were rated lower in skill and higher in psychopathology than those done before his breakdown. The difference in perceived psychopathology persists when ratings for skill level are controlled. There were also differences due to training level of raters and whether or not the paintings were presented in color. 相似文献
63.
64.
Impact of medical and demographic factors on long-term quality of life and body image of breast cancer patients. 总被引:5,自引:0,他引:5
K H?rtl W Janni R K?stner H Sommer B Strobl B Rack M Stauber 《Annals of oncology》2003,14(7):1064-1071
BACKGROUND: The impact of various medical and demographic factors on the quality of life (QoL) of breast cancer patients has been discussed controversially. We investigated the influence of six different factors on long-term QoL and body image of women with primary breast cancer. PATIENTS AND METHODS: Two-hundred and seventy-four breast cancer patients were administered the QoL questionnaire following a mean interval of 4.2 years after primary diagnosis. All women had been primarily treated for stage I to III breast cancer without evidence of distant metastases. QoL was evaluated by using the QLQ-C30 questionnaire Version 2.0. Supplementary scales included body image, satisfaction with surgical treatment, cosmetic result and fear of recurrence. We analyzed the impact of tumor stage, surgical treatment, adjuvant radiotherapy, adjuvant cytotoxic therapy, age and length of follow-up period on the examined outcome parameters. RESULTS: At the time of the follow-up examination, patients showed minor impairment of QoL (mean 67.8) and body image (mean 24.8), but more fear of recurrence (mean 60.7). None of the studied factors had a significant impact on overall QoL (P >0.05) according to the QLQ-C30 questionnaire. In contrast, with the exception of the factors 'cytotoxic therapy' and 'radiotherapy' all investigated variables influenced at least one of the additional psychological scales (P <0.05). The primary surgical treatment modality had the strongest impact and affected all four scales. Patients treated with breast conservation reported a more favorable body image, compared to those treated with mastectomy (17.2 versus 37.5, P <0.01), more satisfaction with surgical treatment (4.0 versus 10.7, P = 0.01), rated a better cosmetic result (75.5 versus 57.1, P <0.01), but presented more fear of recurrence (63.9 versus 55.3, P = 0.04). CONCLUSION: Current QoL questionnaires do not sufficiently cover all relevant aspects of QoL, but might be complemented by breast cancer specific aspects such as body image and fear. 相似文献
65.
Semba RD Muhilal West KP Natadisastra G Eisinger W Lan Y Sommer A 《The American journal of clinical nutrition》2000,72(1):146-153
BACKGROUND: The relations among hyporetinolemia, acute phase proteins, and vitamin A status in children are unclear. OBJECTIVE: The objective was to examine the relations between acute phase proteins and plasma retinol concentrations in children with and without clinical vitamin A deficiency (Bitot spots and night blindness). DESIGN: The study was a nonconcurrent analysis of acute phase protein concentrations and other data from a previous clinical trial. Preschool children, 3-6 y of age, with (n = 118) and without (n = 118) xerophthalmia were assigned to receive oral vitamin A (60 mg retinol equivalent) or placebo and were seen at 5 wk. All children received oral vitamin A (60 mg retinol equivalent) at 5 wk. RESULTS: At baseline, alpha(1)-acid glycoprotein (AGP) was elevated in 42.9% and 23.5% (P < 0.003) and C-reactive protein (CRP) was elevated in 17.7% and 13.7% (NS) of children with and without xerophthalmia, respectively. Hyporetinolemia (retinol < 0.7 micromol/L) occurred in 61.0% and 47.4% (P < 0.04) of children with and without xerophthalmia, respectively. A history of fever, a history of cough, and nasal discharge noted on examination were each associated with elevated acute phase proteins. Vitamin A supplementation increased plasma retinol at 5 wk but had no significant effect on concentrations of acute phase proteins. CONCLUSIONS: Elevated acute phase protein concentrations and infectious disease morbidity are closely associated during vitamin A deficiency. 相似文献
66.
Christian P West KP Khatry SK Kimbrough-Pradhan E LeClerq SC Katz J Shrestha SR Dali SM Sommer A 《American journal of epidemiology》2000,152(6):542-547
Night blindness due to vitamin A deficiency is common during pregnancy among women in Nepal. The authors assessed the risk of maternal death during and after a pregnancy with night blindness among women participating in a cluster-randomized, placebo-controlled vitamin A and beta-carotene supplementation trial in Nepal from July 1994 to September 1997. Subjects were 877 women with night blindness and 9,545 women without night blindness during pregnancy. Women were followed from the time they declared that they were pregnant through the end of the study, representing a median follow-up of 90 weeks (interquartile range: 64-121 weeks). Mortality of night-blind women in the placebo group was 3,601 per 100,000 pregnancies. In comparison, the relative risk of dying among nonnight-blind women in the placebo group was 0.26 (95% confidence interval (CI): 0.13, 0.55), and the relative risk among women with or without night blindness in the vitamin A/beta-carotene group was 0.32 (95% CI: 0.10, 0.91) and 0.18 (95% CI: 0.09, 0.36), respectively. Night-blind women were five times (95% CI: 2.20, 10.58) more likely to die from infections than were women who were not night blind. These findings show that night blindness during pregnancy is a risk factor of both short- and long-term mortality among women. Vitamin A/beta-carotene supplementation ameliorates this risk to a large extent. 相似文献
67.
68.
Janine Bayer Pia Bandurski Tobias Sommer 《The European journal of neuroscience》2013,38(10):3519-3526
Estradiol and progesterone interact with the dopaminergic and other neurotransmitter systems that are involved in the processing of rewards. On the systems level, these hormones modulate responses to stimulants as well as neuronal activity related to the anticipation of monetary gains. As different mechanisms might underlie the processing of gains and losses, the current study aims to investigate whether neural correlates of gain and loss anticipation are differentially modulated by menstrual cycle phases. Therefore, young, naturally cycling women were examined by means of functional neuroimaging during performing a modified version of the ‘Monetary Incentive Delay’ task in the early follicular and in the luteal menstrual cycle phase. During the low hormone early follicular phase, the anticipation of high vs. low gains and losses was associated with activity in a largely overlapping network of brain areas. However, high hormone levels in the luteal phase affected brain activity in these areas differentially during the anticipation of high vs. low gains and losses. In particular, the orbitofrontal cortex showed a reduced sensitivity to gain magnitude, whereas the ventral striatum and the anterior cingulate showed a reduced sensitivity to loss magnitude. In summary, the high amount of progesterone and estradiol in the luteal phase decreased activity related to the anticipation of monetary gains and losses in different brain areas, suggesting that hormones modulate different processes during the anticipation of gain and loss magnitude. 相似文献
69.
70.
Consensus statement on prevention and management of adverse effects following rejuvenation procedures with hyaluronic acid‐based fillers
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W.G. Philipp‐Dormston D. Bergfeld B.M. Sommer G. Sattler S. Cotofana P. Snozzi U. Wollina K.P.J. Hoffmann C. Salavastru K. Fritz 《Journal of the European Academy of Dermatology and Venereology》2017,31(7):1088-1095
Facial fillers play an important role in the correction of facial changes associated with ageing. They offer quick treatments in the outpatient setting with minimal subsequent downtime that provide predictable, natural‐looking, long‐lasting results. Adverse reactions after hyaluronic acid injections tend to be mild or moderate and rather temporary. However, as with all injected or implanted biomaterials, severe adverse events can occur and patients must be fully informed of potential risks prior to undergoing treatment. A panel of experts from Germany (D), Austria (A) and Switzerland (CH) developed recommendations, and this study provides the ‘DACH Consensus Recommendations’ from this group specifically on the use of hyaluronic acid fillers. The aim is to help clinicians recognize potential risks and to provide guidance on how best to treat adverse events if they arise. Contraindications to hyaluronic acid fillers are also detailed, and ways to prevent adverse events occurring are discussed. Hyaluronic acid‐based products are claimed to be very close to an ideal tissue augmentation agent; nevertheless, profound medical, anatomical and product knowledge are of paramount importance to minimize the occurrence of adverse reactions. 相似文献