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排序方式: 共有2169条查询结果,搜索用时 15 毫秒
991.
Olschewski H Simonneau G Galiè N Higenbottam T Naeije R Rubin LJ Nikkho S Speich R Hoeper MM Behr J Winkler J Sitbon O Popov W Ghofrani HA Manes A Kiely DG Ewert R Meyer A Corris PA Delcroix M Gomez-Sanchez M Siedentop H Seeger W;Aerosolized Iloprost Randomized Study Group 《The New England journal of medicine》2002,347(5):322-329
992.
Molecular cloning and characterization of Dr-II, a nonfimbrial adhesin-I-like adhesin isolated from gestational pyelonephritis-associated Escherichia coli that binds to decay-accelerating factor. 总被引:1,自引:0,他引:1 下载免费PDF全文
Bacterial adhesins play an important role in the colonization of the human urogenital tract. Escherichia coli Dr family adhesins have been found to be frequently expressed in strains associated with pyelonephritis in pregnant females. The tissue receptor for known Dr adhesins has been localized to the short consensus repeat-3 (SCR-3) domain of decay accelerating factor (DAF), a complement regulatory protein. In this report, we identified and cloned draE2, a gene encoding a novel 17-kDa DAF-binding adhesin, Dr-II, from a strain of E. coli associated with acute gestational pyelonephritis. Despite the significant sequence diversity between Dr-II and Dr family adhesins, the receptor of Dr-II was found to be the SCR-3 domain of DAF. Sequence analysis of the 186-amino-acid Dr-II open reading frame revealed significant diversity from other members of the Dr adhesin family, including Dr, AFA-I, AFA-III, and F1845, but only an 8-amino-acid difference in sequence from that of the 17-kDa nonfimbrial adhesin NFA-I of unknown receptor specificity. N-terminal peptide sequencing of the purified adhesin confirmed the identity of the open reading frame and indicated cleavage of a 28-amino-acid signal peptide. Antibodies raised against purified Dr-II adhesin exhibited little or no cross-reactivity to Dr adhesin. Characterization of the biological properties demonstrated that like the Dr adhesins, Dr-II was associated with the ability of E. coli to bind to tubular basement membranes and Bowman's capsule and to be internalized into HeLa cells. 相似文献
993.
Séverac Cauquil A Faldon M Popov K Day BL Bronstein AM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,148(3):414-418
To investigate whether the primary planes of eye and body responses to galvanic vestibular stimulation (GVS) are congruent,
we have measured the binocular, three-dimensional eye movements (scleral coil technique) to bilateral bipolar GVS in six normal
human subjects. Stimulation intensities were kept deliberately low in order to characterize the response to near-threshold
intensities of stimulation (0.1–0.9 mA) that had been used previously to characterise body postural responses. Stimuli were
applied for 4 s, but only the early responses that occurred within the initial 300 ms of turning the current on or off were
measured. At intensities of 0.1–0.7 mA the 'on' response consisted almost exclusively of a torsional slow phase eye movement
in which the top of the eyes rotated towards the anode. The latency of the torsional response was ca. 46 ms. A weak polarity-dependent
disconjugate response was also observed in which the intorting eye elevated and the extorting eye depressed ('skew eye deviation').
When the current was turned off similar responses occurred in the reverse direction. Removal of the visual fixation light-emitting
diode (LED) had no consistent effect on the short-latency ocular responses. The direction of the ocular response was similar
to that of the postural response and is compatible with GVS inducing an apparent dynamic roll-tilt of the head towards the
cathode. However, weak horizontal eye movements, which became more prominent as the stimulus intensity was increased to 0.9 mA,
were also observed. This suggests that an additional weak rotational component about the yaw axis, or a component of lateral
translation in the frontal plane, is contained in the GVS-evoked signal. The overall pattern of eye movement suggests that
semicircular canal afferents contribute to these low-intensity GVS responses.
Electronic Publication 相似文献
994.
Kovalev IV Popov AG Baskakov MB Minochenko IL Kilin AA Borodin YL Anfinogenova YD Kapilevich LV Medvedev MA 《Bulletin of experimental biology and medicine》2002,133(1):38-40
Double sucrose gap experiments were carried out to study the effect of phosphodiesterase inhibitors and penetrating analogs of cyclic nucleotides on action potential and contraction of guinea pig ureteral smooth muscle cells. 3-Isobutyl-1-methylxanthine (10 M) and dibutyryl-cAMP (20 M) shortened the plateau of action potential and inhibited contraction of smooth muscle cells by increasing potassium permeability of their membrane. Vinpocetine (1 M) and dibutyryl-cAMP (100 M) strengthened contraction of smooth muscle cells and shortened action potentials by decreasing sodium permeability of their membrane. 相似文献
995.
A. A. Cruz T. Popov R. Pawankar I. Annesi-Maesano W. Fokkens J. Kemp K. Ohta D. Price J. Bousquet 《Allergy》2007,62(S84):1-41
This update aimed to review the new evidence available to support or refute prior Allergic Rhinitis and its Impact on Asthma (ARIA) statements. A Medline search of publications between 2000 and 2005 was conducted, with articles selected by experts. New evidence supports previous ARIA statements, such as: (i) allergic rhinitis (AR) is a risk factor for asthma; (ii) patients with persistent rhinitis should be evaluated for asthma; (iii) most patients with asthma have rhinitis; (iv) a combined strategy should be used to treat the airways and (v) in low- to middle-income countries, a different strategy may be needed. The increased risk of asthma has also been found among sufferers from non-AR. Recent reports show AR is a global problem. Many studies demonstrated parallel increasing prevalence of asthma and rhinitis, but in regions of highest prevalence, it may be reaching a plateau. Factors associated with a reduced risk of asthma and AR have been identified, confirming previous findings of protection related to exposure to infections. Treatment of rhinitis with intranasal glucocorticosteroids, antihistamines, leukotriene antagonists or immunotherapy may reduce morbidity because of asthma. To take advantage of the paradigm of unified airways, there is a need to rationalize diagnosis and treatment to optimize management. 相似文献
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999.
Walker DH Popov VL Feng HM 《Laboratory investigation; a journal of technical methods and pathology》2000,80(9):1361-1372
A mouse model of typhus rickettsiosis that reproduces the hematogenous dissemination to the critical target organs, including brain, lungs, heart, and kidneys, primary endothelial and, to a lesser degree, macrophage intracellular rickettsial infection, and typical vascular-based lesions of louse-borne typhus and murine typhus was established. Intravenous inoculation of C3H/HeN mice with Rickettsia typhi caused disease with a duration of the incubation period and mortality rate that were dependent on the infective dose of rickettsiae. Lethal infection was associated with high concentrations of R. typhi in the lungs and brain, despite a brisker humoral immune response to the rickettsiae than in the sublethal infection. Gamma interferon and CD8 T lymphocytes were demonstrated to be crucial to clearance of the rickettsiae and recovery from infection in experiments in which specific monoclonal antibodies were administered to deplete these components. Death of animals depleted of gamma interferon or CD8 T lymphocytes was associated with overwhelming rickettsial infection demonstrated by titers of infectious rickettsiae and by immunohistochemistry. An effective antirickettsial immune response was associated with elevated serum concentrations of IL-12 on Day 5 and increased secretion of IL-12 by concanavalin-A-stimulated spleen cells on Day 5. Evidence for transient suppression of the immune response consisted of marked reduction in the secretion of IL-2 and IL-12 by concanavalin-A-stimulated spleen cells on Days 10 and 15. This model offers excellent opportunities for study of attenuation and pathogenetic mechanisms of typhus rickettsiae, which are established biologic weapons of potential use in bioterrorism. 相似文献
1000.
I V Antonchenko E O Gimrikh S V Popov A M Chekhov G M Savenkova V I Zhankov E V Borisova 《Kardiologiia》1990,30(3):43-47
A feasibility to provoke reciprocal atrioventricular tachycardias was examined in 23 patients with atrioventricular nodal tachycardia and 17 with orthodromal tachycardia in the presence of the Wolff-Parkinson-White syndrome with endocardiac and transesophageal diagnostic pacing. Atrioventricular nodal tachycardia could be induced in all 23 (100%) patients both by endocardiac and transesophageal pacing. Orthodromal tachycardia was provoked only in 9 (53%) of 17 patients by transesophageal pacing. It was generally noted that tachycardia induction required more "aggressive" regimens of transesophageal pacing than endocardiac one. Endocardiac diagnostic pacing is now a more informative technique, but transesophageal pacing requires further development. 相似文献