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1.
Bronwyn A. Kingwell Lisa Krause Stevo Julius 《Clinical and experimental pharmacology & physiology》1994,21(1):31-39
1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator. 相似文献
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Copolymerization of propene with 1-octene (1 mol/1 mol) was performed in toluene at 40°C in the presence of homogeneous methylaluminoxane (MAO)-activated ansa-metallocenes in order to study the role of benzannelation and 2-methyl-substitution of the silylene-bridged bisindenyl ligand on comonomer incoporation, molecular mass, molecular mass distribution, and end groups. While 2-methyl-substitution promoted higher degree of polymerization without affecting copolymerization parameters, benzannelation improved markedly 1-octene incorporation. Only with MAO-activated rac-Me2Si(2-MeBenz[e]Ind)2ZrCl2 catalysts vinylidene end groups were formed exclusively. Molecular weight distribution remains narrow in all experiments. 相似文献
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Nancy R Sturm Michel Dollet Julius Lukes David A Campbell 《Infection, genetics and evolution》2007,7(5):570-576
The sequences of minicircle conserved regions from various plant trypanosomatids have been determined and analyzed. The goal of this study was to add another tool to the arsenal of molecular probes for distinguishing between the different trypanosomatids occurring in plants: systemic trypanosomatids multiplying in the sap, those from the laticiferous tubes, and those developing in fruits, seeds or flowers but not in the plant itself and that are frequently considered as opportunistic insect trypanosomatids. As some plant intraphloemic trypanosomatids are the causative agents of important diseases, a clear definition of the different types of trypanosomatids is critical. The conserved region of the mitochondrial minicircle provides several specific features in a small sequence region containing three functionally elements required for minicircle replication. Trees generated from the analysis recapitulated trees drawn from analyses of isoenzymes, RAPD, and particular gene sequences, supporting the validity of the small region used in this work. Three groups of isolates were significant and in accordance with previous work. The peculiarity of phloem-restricted trypanosomatids associated with wilts of coconut and oil palm in Latin America - group H - is confirmed. In agreement with previous studies on their biological and serological properties the results highlighted this group called 'phloemicola'. It always differentiated from all other latex and fruit isolates or opportunistic trypanosomatids, like insect trypanosomatids. We can assert that phloemicola is the only well-defined taxon among all plant trypanosomatids. A group of non-pathogenic latex isolates from South American euphorbs (G), and a heterogenous group (A) including one fruit, one possible latex and one insect isolate are clearly distinct groups. The group of Mediterranean isolates from latex (D), even with a low boostrap, stood out well from other groups. The remainder of the isolates fell into a heterogeneous cluster. At least eight different groups in the plant trypanosomatids were identified. 相似文献
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Announcement
Research fellowship in behavioral AIDS research 相似文献7.
Lodenyo H Rana F Mutuma GZ Kabanga JM Kuria JK Okoth FA 《African journal of health sciences》2005,12(1-2):49-54
Upper gastrointestinal complaints are common in Kenya. Though these have remained unchanged over the last 20 years, the pattern of upper gastrointestinal disease on endoscopic examination seems to be changing. There appears to be progressive increase in oesophagitis and cancer of the stomach. Peptic ulcer disease has remained stable while Cancer of the oesophagus is still common. The paper intends to report on endoscopic findings at the Centre for Clinical Research, Kenya Medical Research Institute (KEMRI) over the period October 1998 and May 2001. The sources of information are records made at the time of endoscopy and histology reports on biopsies taken. Seven hundred and sixty eight patients were endoscoped. The male to female ratio was 1.7:1 with mean age +/-SD of 40.8 +/-20.1 years and age range was 3 to 96 years. Majority of the patients had abnormal findings with gastritis being the most common ( 25.8%). It is concluded that gastritis is an important cause of morbidity in Kenya. Oesophagitis, mainly due to gastroesophageal reflux disease, seems to be on the increase. Gastric cancer is not as rare as previously thought and peptic ulcer disease is still common. 相似文献
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Specificity of IgA cold agglutinins: anti-Pr 1 总被引:3,自引:0,他引:3
D Roelcke 《European journal of immunology》1973,3(4):206-212
Monoclonal cold agglutinins have usually been found to be IgM(k) and to be directed against the I/i antigens. Three IgA(k) cold agglutinins were tested for antibody specificity. Based on the following criteria, they were shown to be directed against the Pr1 antigen of the Pr1/Pr2/Pra antigen system. The antigens reacting with the IgA(k) cold agglutinins were inactivated by protease and treatment of human red cells with neuraminidase and were demonstrable on human erythrocyte glycoproteins. The terminal sugar of the determinant group of these antigens is N-acetylneuraminic acid (NANA), which is not involved in I/i, but also in Pr2 antigenicity. The antigen activity of these antigens and the Pr2 and I antigen activities were distributed to different glycopeptide fractions obtained from red cell glycoproteins by ficin cleavage and Sephadex G-50 separation. Periodate oxidation of red cell glycoproteins, which causes a shortening of the polyhydroxy side chain at C-6 of C-9 NANA to a C-7 and/or C-8 NANA derivative, resulted in inactivation of these antigens, while the I antigen remained unchanged and the Pr2 antigen was increased 16–64-fold. Dog red cells gave no or diminished reactions with the three IgA(k) cold agglutinins, in contrast to increased reaction with anti-Pr2. Based on the different reactions of the IgA(k) cold agglutinins with dog red cells, a Pr1 heterogeneity Pr1h/Pr1d was demonstrated. In spite of the determination of the Pr1h/Pr1d/Pr2 and the MN antigens by NANA, both antigen systems were shown to be unrelated. Blocking of free ε-lysine amino groups by acetylation or blocking of the NANA carboxyl groups by amidation of red cell glycoproteins resulted in MN inactivation, while the antigens reacting with the IgA(k) cold agglutinins (like Pr2) remained unaffected. The anti-Pr1 specificity of IgA cold agglutinins and the predominance of anti-I/-i specificity of IgM cold agglutinins was discussed with respect to inter-relations between immunoglobulin classes and antibody specificities of cold agglutinins. 相似文献
10.
Yewande E. Odeyemi ODene Lewis Julius Ngwa Kristen Dodd Richard F. Gillum Alem Mehari 《Journal of the National Medical Association》2019,111(1):94-100