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1.
1. The action of (1-28) alpha-human atrial natriuretic peptide (ANP) was studied on human isolated resistance arteries. 2. Renal, skeletal muscle, omental and subcutaneous resistance arteries were taken from tissue removed at surgery and isometric tension responses were measured with a myograph. 3. ANP (10(-9)-10(-6) M) relaxed precontracted segments of renal and skeletal muscle arteries in a concentration-dependent manner. ANP failed to relax isolated omental or subcutaneous arteries. 4. The effect of ANP on human isolated resistance arteries varies depending on the site of origin of the artery. 相似文献
2.
Acute myelocytic leukemia and prior allergies 总被引:1,自引:0,他引:1
R K Severson S Davis D B Thomas R G Stevens L Heuser L E Sever 《Journal of clinical epidemiology》1989,42(10):995-1001
The relationship between prior allergies and adult acute myelocytic leukemia was investigated in a population-based case-control study. Based on data from personal interviews of 98 cases and 133 controls, a history of any type of allergy was associated with a significantly decreased risk of acute myelocytic leukemia (OR = 0.35, 95% CI = 0.20-0.60). Risk declined with the total number of specific allergies reported (p less than 0.001), and was reduced in relation to a history of prior asthma, eczema and hives. The implications of these findings in relation to natural immune surveillance against developing neoplasms are discussed. 相似文献
3.
J L Sever J H Ellenberg A C Ley D L Madden D A Fuccillo N R Tzan D M Edmonds 《International journal of epidemiology》1992,21(2):285-292
A matched case-control methodology was used to assess the risk for a wide range of abnormalities in children associated with serological evidence for 'TORCH' infections in the mothers. Specimens were selected from the large bank of sera from the approximately 54,000 pregnant women who participated in the Collaborative Perinatal Project. There was no clear association between any of the antigens studied and any specific damage to the child. These 'negative' findings are consistent with the absence of frequent significant effects due to these agents in the second and third trimesters of pregnancy. 相似文献
4.
No evidence for a direct vasodilatory effect of celiprolol on human vasculature in vivo or in vitro 总被引:1,自引:0,他引:1
A Hughes G Martin P Goldberg S Thom P Sever 《Journal of cardiovascular pharmacology》1987,10(5):589-592
Celiprolol is reported to be a new cardioselective beta blocker with novel ancillary properties including vasodilator effects. The purpose of this study was to investigate whether celiprolol possesses a direct vasodilatory effect on human vasculature in vivo and in vitro. We studied the in vivo effects of intra-arterial celiprolol (1-100 micrograms/min i.a.) on forearm blood flow (FBF). Forearm blood was measured by venous occlusion plethysmography. Possible vasorelaxant actions of celiprolol on human vascular smooth muscle were studied using segments of isolated human saphenous vein in vitro. The effect of celiprolol was investigated on resting tone or noradrenaline induced tone. Possible alpha 2-adrenoceptor antagonist effects of celiprolol were assessed using celiprolol as an antagonist of BHT933 induced constriction. Celiprolol was without significant effect on FBF and failed to relax isolated saphenous vein segments preconstricted with noradrenaline. The weak alpha 2-adrenoceptor antagonist action of celiprolol was demonstrable in human saphenous vein. This study does not provide evidence for a direct vasodilatory effect of celiprolol on human vasculature. 相似文献
5.
David M. Sever 《Anatomical record (Hoboken, N.J. : 2007)》1992,233(2):229-244
Cloacae were examined from male and female salamanders representing 12 genera and 22 species in the Salamandridae. All female salamandrids possess numerous sperm storage glands, spermathecae, in the roof of the cloaca, but intergeneric variation exists in the occurrence of additional cloacal glands. Pleurodeles and Tylototriton possess both vent and anterior ventral glands, and secondary loss has occurred of vent glands in all other genera and anterior ventral glands in Chioglossa, Cynops, Paramesotriton, and Triturus The most highly derived cloaca occurs in Euproctus asper, in which the cloacal tube extends through a conical projection, and ventral glands secrete onto the dorsolateral surface of the projection rather than into the cloaca. Marked intergeneric variation occurs in males in conformation of the cloacal cavities and in extent of the dorsal gland. In Cynops, Euproctus, Pachytriton, Paramesotriton, Taricha, and Triturus, the pseudopenis (a broad, posteriorly projecting evagination of the dorsal roof) fills much of the cavity of the anterior cloacal chamber. In most salamandrids, distal ends of the dorsal glands occur lateral to pelvic glands in the anterior end of the cloaca, and dorsal gland tubules descend to secretory sites at the posterior end of the vent. Salamandra and Mertensiella possess a unique, bifurcated dorsal gland in which distal ends of tubules lie dorsal to the other cloacal glands, and proximal ends curve ventrally in the anterior end of the cloaca to secretory sites along the cloacal orifice. Cladistic analyses indicate that the variation in presence of anterior ventral glands is due to homoplasy. The occurrence of female vent glands, bifurcated dorsal glands, and the pseudopenis supports a phylogeny based upon noncloacal characters. © 1992 Wiley-Liss, Inc. 相似文献
6.
Persistent Varicella-Zoster virus infection in a human rhabdomyosarcoma cell line and recovery of a plaque variant. 下载免费PDF全文
Varicella-zoster virus (VZV) has been found to persistently infect the human rhabdomyosarcoma cell line A204. Infectious center assays and fluorescent antibody staining demonstrated continuous production of infectious VZV and viral antigen. The level of infection determined by fluorescent antibody staining was variable, and usually only a small percentage of the cells were capable of producing plaques in permissive fibroblasts. The extent of infection was similar in cell cultures passaged at split ratios of 1:2 or 1:10 and grown at 33 or 37 degrees C. VZV recovered from A204 cells several months after establishment of the persistent infection had markedly increased syncytia-forming activity as compared with the parental VZV grown in human diploid fibroblast cells and the three monkey kidney-derived cell lines Vero, CV-1, and MA104. The expression of this altered phenotype continued after serial passage of the cell-associated virus in human diploid fibroblast and Vero cells. Consequently, we designated the reisolated VZV as plaque variant A. The buoyant densities of VZV plaque variant A and VZV DNAs in CsCl gradients were indistinguishable. 相似文献
7.
John L. Sever Nancy R. Tzan Isabel C. Shekarchi David L. Madden 《Journal of clinical microbiology》1983,17(1):52-54
The latex agglutination card test (Rubascan) for the detection of rubella antibody was compared with the standard hemagglutination inhibition and enzyme-linked immunosorbent assay tests. There was complete agreement with sera which had hemagglutination inhibition titers of ≥16. Sera with low levels of antibody which were positive in the enzyme-linked immunosorbent assay, however, gave negative latex agglutination results approximately 25% of the time (false negatives), whereas sera which were negative in the enzyme-linked immunosorbent assay gave false-positive results in about 3% of the cases. The use of capillary “finger stick” plasma instead of venous sera resulted in additional false-negative latex agglutination tests among patients with very low antibody titers. Because of the simplicity of the method, it should be possible to use this test in physicians' offices and in large immunization campaigns. Care should be taken to become completely familiar with the procedures and reading of the agglutination patterns. Control sera should always be used. Interpretation of results should take into consideration the rates of false-negative and false-positive results noted above. These rates apply to sera with little or no antibody. In particular, negative tests should be confirmed with more specific methods in critical cases, such as pregnant women exposed to rubella or women of childbearing age who are being considered for immunization. There was no problem with the latex agglutination findings for sera with higher titers. Since results are available in 8 min, physicians should be able to counsel their patients rapidly and immunize, if necessary, while the patient is still present. 相似文献
8.
Microsticks as solid-phase carriers for enzyme-linked immunosorbent assays. 总被引:1,自引:1,他引:1 下载免费PDF全文
Microsticks are machine-tooled or molded pegs of plastic or stainless steel which were developed as solid-phase carriers for the enzyme-linked immunosorbent assay (ELISA). They consist of a stem, which can be coated with plastic to be used as the reactive surface, and a shaft designed for easy handling and labeling and for positioning the sticks in microtiter wells and transfer plates. Microsticks permit a wide selection of coating materials and afford the user greater control over quality and standardization of the solid-phase surface. Polycarbonate and nitrocellulose coatings were tested in ELISAs for antibodies to measles virus, toxoplasma, and human gamma globulin. The Microsticks were found to give reproducible, sensitive, and specific ELISA results and minimized problems due to lot-to-lot and batch-to-batch variations found with other plastic carriers. 相似文献
9.
Involvement of JC virus-infected mononuclear cells from the bone marrow and spleen in the pathogenesis of progressive multifocal leukoencephalopathy 总被引:18,自引:0,他引:18
10.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2