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911.
912.
Sommer F Klotz T Steinritz D Schmidt A Addicks K Engelmann U Bloch W 《International journal of impotence research》2002,14(4):217-225
Nitric oxide (NO) is an important mediator in the cavernosal smooth muscle relaxation that causes erections. The purpose of this study was to examine the existence, distribution and phosphorylation stage of two recently discovered key enzymes for NO regulation in human cavernosal tissue, the MAP Kinase 1/2 (Erk 1/2) and the serine/threonine specific protein kinase Akt/PKB. The expression of the enzymes was examined in corpus cavernosum specimens taken from both potent men and from patients with long-term impotence. There was a distinct difference in the activation stage of the MAP Kinase 1/2 (Erk 1/2) between endothelium and smooth muscle cells in potent patients. This finding gives evidence for a cell-type-specific regulation of the eNOS-dependent NO release. Furthermore, we found a higher basal level of active MAP Kinase 1/2 (Erk 1/2) in impotent patients. This finding gives the first evidence for an inhibitory influence of MAP Kinase 1/2 (Erk 1/2) on cavernosal eNOS activity. 相似文献
913.
Sommer F Schwarzer U Wassmer G Bloch W Braun M Klotz T Engelmann U 《International journal of impotence research》2002,14(5):379-383
Francois Gigot de la Peyronie, surgeon to Louis XV of France, has become synonymous with the rather enigmatic though not uncommon condition of Peyronie's disease (PD), a localized connective tissue disorder of the penile tunica albuginea. The true prevalence of Peyronie's disease is unknown. Therefore, we decided to perform an evaluation of existing epidemiological data. A prevalence rate of 3.2% was determined in male inhabitants of the greater Cologne area. This is much higher than revealed by the data reported up to now, thus rendering the accepted prevalence rates of 0.3% to 1% untenable. The actual prevalence of Peyronie's disease may be even higher, considering many patients' reluctance to report this embarrassing condition to their physicians. Along these lines, most clinicians note that the number of Peyronie's patients has increased since the advent of oral sildenafil. Comparably high prevalences are known for diabetes and urolithiasis, suggesting a greater frequency of this rare disease than formerly believed. 相似文献
914.
Niess AM Fehrenbach E Schlotz E Sommer M Angres C Tschositsch K Battenfeld N Golly IC Biesalski HK Northoff H Dickhuth HH 《International journal of sports medicine》2002,23(6):445-452
Previous research revealed an increased expression of HSP72 in leukocytes after vigorous endurance exercise. We questioned whether more intensive but shorter exercise also induces leukocyte HSP72 synthesis. To delineate the role of reactive oxygen species (ROS) in exercise-related HSP72 induction, we additionally examined the effect of RRR-alpha-tocopherol (alpha-toc) on HSP72 expression using a double-blind placebo (P) controlled cross-over design. After supplementation with alpha-toc (500 I.U. daily) or P for 8 days, 9 male subjects performed a combined exhaustive treadmill protocol (total duration 29.4 +/- 2.0 min). HSP72 was assessed on mRNA (RT-PCR) and protein levels (flow cytometry). HSP72 mRNA rose 3 h after exercise only in the P group, but individual differences (alpha-toc - P) did not reveal significant treatment effects. A moderate but significant rise of HSP72 protein occurred in granulocytes up to 48 h after exercise. Three hours post-exercise, granulocyte HSP72 protein was lower when subjects received alpha-toc, but this effect vanished 24 and 48 h post-exercise. Exhaustive treadmill exercise augments HSP72 mRNA in leukocytes and induced a moderate but prolonged response of granulocyte HSP72 protein. These exercise effects are lower when compared to earlier findings obtained after vigorous endurance exercise. ROS seem to be involved, but do not play the major role in the induction of granulocyte HSP72 synthesis after exhaustive exercise. 相似文献
915.
PURPOSE: 2-Methoxyestradiol (2ME(2)), a metabolite of 17beta-estradiol, is currently undergoing extensive clinical testing as an antitumor agent. This drug antagonizes both angiogenesis and induces apoptosis in some tumor cell lines. Growth plate alterations as well as an inhibition of longitudinal bone growth have been reported in young rats treated with a pharmacological dose of 2ME(2). However, 2ME(2)'s mechanism of action at the growth plate is unknown. To uncover the mechanism, we examined the dose-response effects of 2ME(2) on growth plate chondrocytes. METHODS: 2ME(2) (4-, 20-, and 75 mg.kg.day) was administered orally to recently ovariectomized 10-week-old rats. The number of cells undergoing DNA synthesis was evaluated with (3)H-thymidine radioautography, apoptosis-induced DNA fragmentation was detected with TUNEL assay, and longitudinal growth rates were determined with fluorochrome labeling. RESULTS: 2ME(2) reduced bone elongation ( P< or =0.05), suppressed chondrocyte proliferation ( P< or =0.05), and induced chondrocyte apoptosis ( P< or =0.05). Furthermore, 1-week treatment with 2ME(2) did not affect the size of hypertrophic chondrocytes. CONCLUSION: Thus, pharmacological doses of 2ME(2) utilized for tumor suppression can inhibit normal bone elongation in growing rats by reducing the number of proliferating chondrocytes in the growth plate and accelerating apoptosis in differentiated chondrocytes. This demonstration identifies another organ in which toxicity should potentially be monitored in ongoing and future clinical trials of 2ME(2). 相似文献
916.
When monkeys are presented simultaneously with multiple stimuli, they can make one of two types of response. Either they make averaging saccades, that land at intermediate locations between the targets, or target-directed saccades, that land close to one of the targets. The two types of saccades occur at different latencies and are thought to reflect different processes; fast reflexive averaging and slower target selection. We investigated the latency of averaging saccades in five monkeys, with particular emphasis on 'express' latency saccades, which are thought to be inhibited by target selection. Express averaging saccades were made prolifically by the two monkeys that made both express and regular latency saccades, but only when no specific instruction was given regarding the saccade target. When these monkeys had to choose one of the targets, on the basis of its color, they still made averaging saccades. However, the endpoints formed two distributions close to the targets as opposed to one single distribution centered between the targets, as was the case when targets were identical; also, express saccades were almost entirely absent. We conclude that express averaging saccades are a form of spatial and temporal optimization of gaze shifting. 相似文献
917.
918.
The atypical antipsychotic, clozapine has some selectivity for dopamine D4 receptors and is a silent antagonist at these receptors. NGD 94-1 (2-phenyl-4(5)-[4-(2-pyrimidinyl)-piperazin-1-yl-methyl]-imidazole ) is a highly selective dopamine D4 receptor ligand recently introduced as a putative antipsychotic mimicking the dopamine D4 receptor antagonist effects of clozapine. We show that NGD 94-1 is not silent. It behaved as an agonist in human embryonic kidney 293 cells expressing human recombinant dopamine D4.4 receptors. This questions the clinical use of NGD 94-1. 相似文献
919.
H Sommer H N?schel B Liebold U Kaufmann 《Zentralblatt für Gyn?kologie》1990,112(20):1285-9; discussion 1291-2, 1293-4
100 patients successfully treated for gynecological tumors and 100 females who never had suffered from a malignant disease were investigated for neurosis by means of a special questionnaire according H?ck and Hess. 52% out of the tumours patients and 42% of the control group demonstrated symptoms and signs of neurosis. The difference was not significant. Patients with tendency to depression or neurosis can be detected with psychometric methods and treated accordingly. 相似文献
920.
K. A. Vergesslich M. Götz G. Mostbeck G. Sommer W. Ponhold 《Pediatric radiology》1989,19(6-7):371-374
Changes of portal venous hemodynamics were investigated in 32 patients with cystic fibrosis (CF) with a mean age of 11.6 years.
Hepatic profile of these patients included total bilirubin and albumin together with determination of size and echogenicity
of the liver and spleen, determination of the diameter of the portal vein by real-time sonography and quantitation of flow
volume of the portal vein using Duplex Doppler sonography. As a control, 35 age matched healthy children were also examined.
Diameter of the portal vein was significantly increased in CF patients versus controls. Comparison of the mean flow volume
of the portal vein showed a significant increase in CF-patients over 12 y old versus controls. In patients less than 12 y
no significant difference of flow volume of the portal vein between CF-patients and controls was noted. The increase of diameter
and flow volume of the portal vein suggest an adaptive mechanism in the pressure-volume relationship of the portal venous
system in patients with CF. 相似文献