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22.
E Przegaliński B Budziszewska A Warcho?-Kania E B?aszczyńska 《Pharmacology, biochemistry, and behavior》1989,33(2):329-334
The selective 5-HT1A receptor agonist 8-OH-DPAT increased serum corticosterone concentration in rats in a dose-dependent manner. The synthetic corticoid dexamethasone lowered the serum corticosterone level and abolished its rise induced by 8-OH-DPAT. The corticosterone response to 8-OH-DPAT was also antagonized by spiperone, (+/-)- and (-)-pindolol and (+/-)-propranolol, all of which have been shown to have a high affinity for 5-HT1A receptors, though in most cases no complete blockade was found. A partial antagonism of the response was also observed after flumazenil, a benzodiazepine antagonist. On the other hand, the 5-HT1B receptor antagonist 21009, the 5-HT2 receptor antagonists ketanserin and pirenperone, the 5-HT3 receptor antagonist ICS 205-930, the alpha 2-adrenoceptor antagonists yohimbine and idazoxan, the beta-adrenoceptor blocker with no affinity to 5-HT1 receptors, atenolol, the dopaminergic antagonist pimozide, the histamine receptor blocker chloropyramine and the opiate receptor antagonist naloxone did not affect the hormonal response to 8-OH-DPAT. The 8-OH-DPAT-induced corticosterone secretion was not affected either in rats pretreated with p-chlorophenylalanine (PCPA, an inhibitor of tryptophan hydroxylase) or p-chloroamphetamine (PCA, a drug-inducing lesion of serotonergic nerve terminals). It is concluded that 8-OH-DPAT-induced increase in serum corticosterone concentration results from its action at a site different than the adrenal cortex and is mediated by postsynaptic 5-HT1A receptors, whereas other subtypes (5-HT1B, 5-HT2, 5-HT3) of 5-HT receptors do not participate in this response.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
23.
Marcela Hernández Hoyos Piotr Orłowski Ewa Piątkowska-Janko Piotr Bogorodzki Maciej Orkisz 《International journal of computer assisted radiology and surgery》2006,1(1):51-61
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and
the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one
acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed
based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction,
multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment
between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients,
by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries.
In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively.
In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery.
Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby
permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA. 相似文献
24.
Piotr Podolec Grzegorz Kope? Jakub Podolec Piotr Wilko?ek Marek Krochin Pawe? Rubi? Marcin Cwynar Tomasz Grodzicki Krzysztof Zmudka Wies?awa Tracz 《Hypertension research》2007,30(12):1151-1158
The objectives of this study were to determine the relationship between carotid-femoral (cfPWV) and aortic pulse wave velocity (aPWV) and to compare their modulators and association with coronary artery disease (CAD). We studied 107 consecutive patients (68 men) with a mean age of 60.49+/-8.31 years who had stable angina and had been referred for coronary angiography. cfPWV and aPWV were measured simultaneously during cardiac catheterization using the Complior device and aortic pressure waveform recordings, respectively. Based on the presence or absence of significant coronary artery stenosis (CAS) patients were subdivided into a CAS+ or CAS- group. The mean values of cfPWV and aPWV were 10.65+/-2.29 m/s and 8.78+/-2.24 m/s, respectively. They were significantly higher in the CAS+ (n=71) compared with the CAS- (n=36) group and predicted significant CAS independently of cardiovascular risk factors and mean or systolic aortic blood pressure. aPWV and cfPWV were significantly correlated (r=0.70; p<0.001) but the degree of correlation differed significantly (p<0.03) between the CAS+ (r=0.74, p<0.001) and CAS- group (r=0.46, p=0.003). Age and mean aortic blood pressure were independent predictors for aPWV as well as cfPWV. In the receiver operating characteristic (ROC) analysis, aPWV and cfPWV had similar accuracy in identification of significant CAS (AUC [area under the ROC curve]=0.76 and 0.69, respectively; p=0.13). However, neither cfPWV nor aPWV was effective at differentiating the extent of CAD. In conclusion, aPWV and cfPWV are highly correlated parameters with similar determinants and comparable accuracy in predicting significant CAS. The strength of correlation between these two indices differed significantly between subjects with and those without CAS. 相似文献
25.
Summary During studies on the helminth fauna of wolves inhabiting natural ecosystems of Poland, 86 scats were examined. All the samples
were collected in the autumn of 2005. Spirocerca lupi was detected with decantation and flotation techniques. The prevalence was 2.32 %. This is the first record of the parasite
from Poland and the third case of its occurrence in the wolf (Canis lupus L.) within its distribution range. 相似文献
26.
27.
W Peczyńska-Czoch 《Archivum immunologiae et therapiae experimentalis》1987,35(2):125-128
alpha-Carboline substituted at C-6 with hydroxy-group is oxidized by human ceruloplasmin and fungal laccase into reactive intermediate which dimerizes, while 6-amino-alpha-carboline subjected to action of both enzymes yields the polymeric products. To prepare sufficient quantities of compounds needed for structure elucidation studies, laccase, immobilised in polyacrylamide gel was employed as a convenient reagent. The resulting products are suggested to be metabolities of 6-hydroxy- and 6-amino-alpha-carbolines formed in vivo. 相似文献
28.
Antioxidative and anti-inflammatory effects of repaglinide in plasma of diabetic animals. 总被引:5,自引:0,他引:5
Anna Gumieniczek Hanna Hopka?a Jacek Roliński Agnieszka Bojarska-Junak 《Pharmacological research》2005,52(2):162-166
Oxidative stress, defined as an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense, is considered to be an important pathogenic factor in diabetes mellitus and its complications. In diabetic state, ROS might also be implicated in promoting a state of systemic inflammation. Recently, it was demonstrated that antioxidant therapy could be used to stop the initiation and propagation of this inflammatory response. Repaglinide is a new oral antidiabetic agent with a possible antioxidant activity. Therefore, in the present study, a possible therapeutic value of repaglinide in ameliorating the oxidative and inflammatory processes was tested in diabetic animals. In the study, the levels of total antioxidant status (TAS), ascorbic acid (AA), protein carbonyl groups (PCG) and interleukin-6 (IL-6) were determined in plasma of diabetic rabbits after 4 and 8 weeks of repaglinide treatment (1mg daily). Ex vivo analysis revealed that there were significant differences in these markers between hyperglycemic and control animals (P<0.05). Some of these parameters were ameliorated by repaglinide treatment. In diabetic rabbits treated with repaglinide, protein oxidation was diminished by 17.8% after 8 weeks of experiment. The level of AA in plasma of diabetic treated animals was higher than in non-treated diabetic groups (by 9.4 and 22.6% after 4 and 8 weeks, respectively). In diabetic treated animals, the TAS level was also significantly increased (by 23.6 and 16.7%). However, in diabetic rabbits, repaglinide did not affect the concentration of IL-6. 相似文献
29.
30.
S Zawadziński G Benke S Eluszkiewicz A Wasikowski S Zarek 《Chirurgia narzadów ruchu i ortopedia polska》1990,55(2):145-148
The activity and principles of administration of Taurolin have been presented. That drug was used in 15 patients with chronic osteitis. Healing by first intention was obtained in 10 patients, necrosis of the skin occurred in 3 patients, recurrence of inflammation was found in one patient in whom accessory sequestroctomy was performed in the last case of osteitis and arteriosclerosis healing was obtained by second intention. The clinical observation of 15 patients has revealed: a) irritating influence of Taurolin on the soft tissue, b) increased phase of secretion of exudate since the 5 day after surgery, c) bactericidal influence of the drug. Sterilization of the focus occurred at 2 to 3 weeks after surgery. The use of Taurolin requires experience, complete abiding by the principles of use of this drug and equipment with a set of Charrier's drains. The authors are carrying on further observation of the use of Taurolin in the treatment of osteitis. 相似文献