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71.
72.
Pittalà V Romeo G Salerno L Siracusa MA Modica M Materia L Mereghetti I Cagnotto A Mennini T Marucci G Angeli P Russo F 《Bioorganic & medicinal chemistry letters》2006,16(1):150-153
The discovery of a new series of selective and high-affinity alpha(1)-adrenoceptor (alpha(1)-AR) ligands, characterized by a 1H-pyrrolo[2,3-d]-pyrimidine-2,4(3H,7H)-dione system, is described in this paper. Some synthesized compounds, including 20, 22, and 30, displayed affinity in the nanomolar range for alpha(1)-ARs and substantial selectivity with respect to 5-HT(1A) and dopaminergic D(1) and D(2) receptors. Functional assays, performed on selected derivatives, showed antagonistic properties. 相似文献
73.
Claudia Tresoldi Elena Bianchi Alessandro Filippo Pellegata Gabriele Dubini Sara Mantero 《Computer methods in biomechanics and biomedical engineering》2017,20(10):1077-1088
The in vitro replication of physiological mechanical conditioning through bioreactors plays a crucial role in the development of functional Small-Caliber Tissue-Engineered Blood Vessels. An in silico scaffold-specific model under pulsatile perfusion provided by a bioreactor was implemented using a fluid-structure interaction (FSI) approach for viscoelastic tubular scaffolds (e.g. decellularized swine arteries, DSA). Results of working pressures, circumferential deformations, and wall shear stress on DSA fell within the desired physiological range and indicated the ability of this model to correctly predict the mechanical conditioning acting on the cells-scaffold system. Consequently, the FSI model allowed us to a priori define the stimulation pattern, driving in vitro physiological maturation of scaffolds, especially with viscoelastic properties. 相似文献
74.
Mohammed-Said Bouaouda Filippo Barattolo Abdelmalek El Kamar 《Revue de Micropaléontologie》2009,52(2):107
The recent biostratigraphic and micropaleontologic works permitted to specify the distribution of Megaporellaboulangeri Deloffre and Beun in the Jurassic of the Moroccan Atlantic basin. The lower limit of the extension of this dasycladale alga, earlier attribued to the Early Kimmeridgian by Deloffre and Beun (1986), is currently placed in the Early Callovian, on the basis of the age provided by Megaporellaboulangeri biozone. The Otternstellaarabica biozone dates the upper limit of the extension of the species of the Early Oxfordian. Megaporellaboulangeri proliferates in the borders of the basin where the internal lagoons facies dominate, however it is absent in the western parts with open sea facies. 相似文献
75.
Filippo Barbanera Monica Guerrini Aleem A. Khan Panicos Panayides Pantelis Hadjigerou Christos Sokos Sundev Gombobaatar Sarah Samadi Bakht Y. Khan Sergio Tofanelli Giorgio Paoli Fernando Dini 《Biological invasions》2009,11(2):333-348
Mediterranean red-legged (Alectoris rufa) and rock (Alectoris graeca) partridge populations are affected by genetic pollution. The chukar partridge (Alectoris chukar), a species only partly native to Europe, is the most frequently introgressive taxon detected in the genome of hybrid partridges.
Both theoretical (evolutionary) and practical (resources management) matters spur to get insight into the geographic origin
of the A. chukar hybridizing swarm. The phenotypic A. rufa populations colonizing the easternmost part of the distribution range of this species, the islands of Elba (Italy) and Corsica
(France), were investigated. The analysis of both mitochondrial (mtDNA: Cytochrome-b gene plus Control Region: 2,250 characters) and nuclear (Short Tandem Repeats, STR; Random Amplified Polymorphic DNA, RAPD)
genomes of 25 wild (Elba) and 20 captive (Corsica) partridges, disclosed spread introgression of chukar origin also in these
populations. All mtDNA haplotypes of Elba and Corsica partridges along with those we obtained from other A. rufa (total, n = 111: Italy, Spain, France) and A. graeca (n = 6, Italy), were compared with the mtDNA haplotypes of chukars (n = 205) sampled in 20 countries. It was found that the A. chukar genes detected in red-legged (n = 43) and rock partridges (n = 4) of Spain, France and Italy as well as in either introduced (Italy) or native (Greece, Turkey) chukars (n = 35) were all from East Asia. Hence, a well-defined geographic origin of the exotic chukar genes polluting the genome of
native Mediterranean A. rufa and A. graeca (inter-specific level) as well as A. chukar (intra-specific level), was demonstrated. 相似文献
76.
The influence of the biomechanical parameters of the hip on the outcome of treatment of hips subject to avascular necrosis of the femoral head 总被引:1,自引:0,他引:1
Dolinar D Kralj-Iglic V Iglic A Antolic V Herman S Pavlovcic V 《Cellular & molecular biology letters》2002,7(1):109-111
We were interested in whether or not the biomechanical status of the hip influences the course of avascular necrosis of the femoral head. To investigate this, we used a computer aided system based on a three dimensional mathematical model for determining the stress distribution in the hip joint from standard anteroposterior rentgenographs (X-ray images) of both hips and pelvis. Based on the results of our study, we suggest that the biomechanical parameters of the hip play an important role in the outcome of treatment of hips affected by avascular necrosis of the femoral head. 相似文献
77.
Endothelin-1 (ET-1) (10 pmol) microinjected into the superficial layer of superior colliculus induces decreases in blood pressure (control, 108 +/- 5 mmHg, n=6; ET-1, 71 +/- 4 mmHg, n=5). The effects on blood pressure induced by endothelin-1 were significantly (p<0.05) reduced by pre-administration into the superior colliculus of the alpha1-adrenoceptor agonist phenylephrine (1 nmol) (46 +/- 5%, n=5), beta1-adrenoceptor antagonist acebutolol (5 nmol) (51 +/- 6%, n=5) or beta1/beta2-adrenoceptor antagonist propranolol (3.4 nmol) (51 +/- 11%, n=5). In contrast, endothelin-1-induced effects were increased (p<0.05) by microinjections into the superior colliculus of prazosin (2.4 nmol) (49 +/- 7%, n=5), an alpha1-adrenoceptor antagonist; dobutamine (4 nmol) (51 +/- 9%, n=5), a beta1-adrenoceptor agonist or isoprenaline (1 nmol) (49 +/- 6%, n=5), a beta1/beta2-adrenoceptor agonist. No involvement of alpha2- or beta2-adrenoceptors has been detected. Therefore, ET-1 induces decreases in blood pressure with selective involvement of alpha1- and beta1-adrenoceptors. 相似文献
78.
Murakami Y Pasqualetti M Takio Y Hirano S Rijli FM Kuratani S 《Development (Cambridge, England)》2004,131(5):983-995
During development, the vertebrate hindbrain is subdivided along its anteroposterior axis into a series of segmental bulges called rhombomeres. These segments in turn generate a repeated pattern of rhombomere-specific neurons, including reticular and branchiomotor neurons. In amphioxus (Cephalochordata), the sister group of the vertebrates, a bona fide segmented hindbrain is lacking, although the embryonic brain vesicle shows molecular anteroposterior regionalization. Therefore, evaluation of the segmental patterning of the central nervous system of agnathan embryos is relevant to our understanding of the origin of the developmental plan of the vertebrate hindbrain. To investigate the neuronal organization of the hindbrain of the Japanese lamprey, Lethenteron japonicum, we retrogradely labeled the reticulospinal and branchial motoneurons. By combining this analysis with a study of the expression patterns of genes identifying specific rhombomeric territories such as LjKrox20, LjPax6, LjEphC and LjHox3, we found that the reticular neurons in the lamprey hindbrain, including isthmic, bulbar and Mauthner cells, develop in conserved rhombomere-specific positions, similar to those in the zebrafish. By contrast, lamprey trigeminal and facial motor nuclei are not in register with rhombomere boundaries, unlike those of gnathostomes. The trigeminal-facial boundary corresponds to the rostral border of LjHox3 expression in the middle of rhombomere 4. Exogenous application of retinoic acid (RA) induced a rostral shift of both the LjHox3 expression domain and branchiomotor nuclei with no obvious repatterning of rhombomeric segmentation and reticular neurons. Therefore, whereas subtype variations of motoneuron identity along the anteroposterior axis may rely on Hox-dependent positional values, as in gnathostomes, such variations in the lamprey are not constrained by hindbrain segmentation. We hypothesize that the registering of hindbrain segmentation and neuronal patterning may have been acquired through successive and independent stepwise patterning changes during evolution. 相似文献
79.
Crisafulli A Melis F Tocco F Santoboni UM Lai C Angioy G Lorrai L Pittau G Concu A Pagliaro P 《American journal of physiology. Heart and circulatory physiology》2004,287(1):H235-H242
In humans, regional myocardial dysfunction during ischemia may be improved by ischemic and pharmacological preconditioning. We assessed the possibility that exercise- and nitroglycerin-induced myocardial preconditioning may improve global cardiac performance during subsequent efforts in patients with angina. Ten patients suffering from chronic stable angina and ten healthy volunteers were studied. Through impedance cardiography we assessed hemodynamics during a maximal exercise test, which was used as a baseline (Bas test) and considered as a preconditioning exercise. The Bas test was followed by a sequence of maximal efforts performed during the first (FWOP; 30 min after the Bas test) and second (SWOP; 48 h after the Bas test) windows of protection conferred by ischemic preconditioning. Hemodynamics was further evaluated during maximal exercise performed 48 h later with pharmacologically induced SWOP (PI-SWOP) obtained by transdermal administration of 10 mg of nitroglycerin. In the angina patients, FWOP, SWOP, and PI-SWOP delayed the time to ischemia and allowed them to achieve higher workloads compared with the Bas test. Furthermore, heart rate and cardiac output at peak exercise were enhanced during all the preconditioning phases with respect to the Bas test. However, only SWOP and PI-SWOP increased myocardial contractility and stroke volume. No changes in hemodynamics were detectable in the control subjects. This study demonstrates that in patients with stable angina, although hemodynamics during exercise can be positively improved during both FWOP and SWOP, differences exist between these two phases. Furthermore, the mimicking of exercise-induced SWOP by PI-SWOP with transdermal nitroglycerin may represent an important clinical aspect. 相似文献
80.
Drago M Chessa M Gianfranco B Bossone E Carminati M 《International journal of cardiovascular interventions》2004,6(3-4):156-159
We describe a case of a congenital coronary artery fistula of the right coronary artery draining into the left atrium in an eight-year-old boy. The initial diagnosis was made after the detection of a continuous cardiac murmur at the age of six years. Transthoracic echocardiography showed the right coronaric ostium dilatation, the site of drainage in the left atrium and left ventricle volume overload. Catheterization confirmed the diagnosis. The patient underwent percutaneous closure by PDA occluder device. Immediate post-closure angiograms showed complete occlusion of the fistula. The patient showed transient ischemic changes on ECG associated to an increase of plasmatic levels of the cardiac enzyme. ECG and cardiac enzyme were normal one week after the procedure. 相似文献