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41.
Previous studies suggest a reduced dopaminergic function in subjects with the A1 (minor) allele of the D2 dopamine receptor (DRD2) gene. To explore influences on visuospatial ability as a function of the DRD2 gene, 182 alcohol- and other drug-naive sons (age 10–14) of active alcoholic, recovered alcoholic, and nonalcoholic fathers were administered a visuospatial task (Benton's Judgment of Line Orientation Test) which makes minimal motoric/verbal demands. Visuospatial scores were lower for boys with the A1 allele and for sons of active alcoholics. A1-allele boys made more errors than A2 boys on all 11 of the template lines, with the effect being largest for the rightmost presentations. In contrast, the effect of family history for alcoholism was strongest on both right and left midquadrant presentations. Moreover, separate analyses of the two types of errors produced allele but not family history of alcoholism effects when the two lines were misjudged as farther apart than they actually were and family history but not allele effects where the two lines were misjudged as closer together. These results suggest that polymorphism of the DRD2 gene and family history of alcoholism are dissociable determinants of visuospatial ability and that visuospatial defects previously observed in alcoholics may, in part, be antecedent to their drinking behavior. 相似文献
42.
Schecter AD Berman AB Yi L Ma H Daly CM Soejima K Rollins BJ Charo IF Taubman MB 《Journal of leukocyte biology》2004,75(6):1079-1085
Monocyte chemoattractant protein-1 (MCP-1, CCL2) is a mediator of inflammation that has been implicated in the pathogenesis of a wide variety of human diseases. CCR2, a heterotrimeric G-coupled receptor, is the only known receptor that functions at physiologic concentrations of MCP-1. Despite the importance of CCR2 in mediating MCP-1 responses, several recent studies have suggested that there may be another functional MCP-1 receptor. Using arterial smooth muscle cells (SMC) from CCR2(-/-) mice, we demonstrate that MCP-1 induces tissue-factor activity at physiologic concentrations. The induction of tissue factor by MCP-1 is blocked by pertussis toxin and 1,2-bis(O-aminophenyl-ethane-ethan)-N,N,N',N'-tetraacetic acid-acetoxymethyl ester, suggesting that signal transduction through the alternative receptor is G(alphai)-coupled and dependent on mobilization of intracellular Ca(2+). MCP-1 induces a time- and concentration-dependent phosphorylation of the mitogen-activated protein kinases p42/44. The induction of tissue factor activity by MCP-1 is blocked by PD98059, an inhibitor of p42/44 activation, but not by SB203580, a selective p38 inhibitor. These data establish that SMC possess an alternative MCP-1 receptor that signals at concentrations of MCP-1 that are similar to those that activate CCR2. This alternative receptor may be important in mediating some of the effects of MCP-1 in atherosclerotic arteries and in other inflammatory processes. 相似文献
43.
Hypertension in end-stage renal disease 总被引:6,自引:0,他引:6
44.
Effects of digoxin in infants with congested circulatory state due to a ventricular septal defect 总被引:2,自引:0,他引:2
W Berman S M Yabek T Dillon C Niland S Corlew D Christensen 《The New England journal of medicine》1983,308(7):363-366
Digoxin alone was used to treat a congested circulatory state in 21 infants (mean age, 2.7 months; mean weight, 3.8 kg) with a ventricular septal defect. The dose was adjusted on the basis of pharmacokinetics to achieve a mean steady-state concentration of 1.6 +/- 0.3 ng of digoxin per milliliter of serum. The mean red-cell level of sodium-potassium ATPase fell from 23.1 +/- 7.0 to 12.6 +/- 5.2 nmol per milligram per minute with treatment. Only 6 of the 21 patients had an inotropic response, as reflected by echocardiographic measurements, but the drug was of clinical benefit to 12 infants (including these 6). These results show that not all infants with a congested circulatory state due to a ventricular septal defect benefit from digoxin therapy. Furthermore, in some subjects clinical improvement occurs in the absence of a measurable inotropic response. 相似文献
45.
46.
Bahar M Berman S Grinshpon Y Weissgarten J Averbukh Z Cohen M Chanimov M 《Growth, development, and aging : GDA》2002,66(2):55-62
In most tissues, various cell membrane ion transporting systems are not fully developed and/or maximally active at the prenatal and early postnatal stage. Their progressive development and expression are a function of growth and maturity. We performed a multiple time-point study, in order to investigate the ability of a variety of tissues to maintain appropriate Ca++ and Mg++ homeostasis at different stages of postnatal development. Total intracellular Ca++ in one-week-old rat liver, brain and spinal cord tissues was significantly elevated, compared to mature animals. It increased further through the first three weeks of gestation. Intracellular Ca++ gradually and significantly declined in adult and mature animal groups. Alterations in total intracellular Mg++ of the same tissue samples, although not so profound, paralleled changes in total intracellular Ca++. We conclude that a developmental switch in intracellular Ca++ and Mg++ homeostasis occurs one to three weeks following birth. It might be related to the incomplete development of Ca++ and Mg++ transmembrane transporting systems, previously reported as being only partially expressed at the early postnatal stage. These developmental alterations in total intracellular Ca++ and Mg++ content might serve as a regulatory mechanism, adjusting cell activities to the physiological requirements of the growing and maturing animal. 相似文献
47.
The occurrence of the tropical bedbug (Cimex hemipterus Fabricius) in poultry houses in Israel is described. Despite the heavy infestation serious losses have not been registered and no clinical signs observed. Treatment of the barns and accessories with 2% malathion emulsion gave good results. The parasite invaded human habitations as well. 相似文献
48.
M A Berman M A Nalesnik S B Kapadia C R Rinaldo F Jensen 《American journal of clinical pathology》1986,86(3):366-369
An aggressive visceral form of Kaposi's sarcoma (KS) has been reported in immunosuppressed populations, most notably in patients with acquired immunodeficiency syndrome (AIDS). This presentation contrasts from the indolent skin lesions on the extremities of older males and is distinct enough in the young adult American population to have been included in the working definition of AIDS. The authors describe a case of primary lymphadenopathic KS in an immunocompetent heterosexual 23-year-old man with no epidemiologic, immunologic, or serologic evidence of AIDS. This report emphasizes that a diagnosis of KS in a young American male is not synonymous with the diagnosis of AIDS. 相似文献
49.
F. S. Baranova A. A. Berman Yu. M. Zaretskaya 《Bulletin of experimental biology and medicine》1980,89(1):44-46
1-Antitrypsin (1-AT) reduces the intensity of transformation of human peripheral blood lymphocytes stimulated by phytohemagglutinin. The degree of inhibition is determined by the antiprotease activity of the 1-AT. Maximal inhibition of transformation was shown to be 50%. Participation of 1-AT in the control of activity of lymphoid tissue cells is postulated.Laboratory of Immunogenetics, Research Institute of Transplantology and Artificial Organs, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 1, pp. 35–36, January, 1980. 相似文献
50.
Despite the great promise of immunization and recent progress in immunizing children throughout the developing world, a global crisis in vaccine R&D, supply and delivery is faced. This article reviews how the global US6 billion dollars vaccine market is structured and its attractiveness to vaccine suppliers, the international two-tiered pricing system in which high-income countries generate about 82% of vaccine revenues but represent only 12% of the doses, the impact of schedule divergence as high-income and developing countries introduce different vaccines, the role of the US government, and possible approaches to ameliorate the crisis. 相似文献