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101.
102.
Summary There are at least three alcohol dehydrogenases in Aspergillus nidulans. ADHIII has no obvious physiological function. We describe here the cloning of the ADHIII gene (alcC), its mapping on linkage group VII by reverse genetics, and the properties of multicopy transformants tested for their ability to grow on a range of alcohols (butan-1-ol being the best substrate tested for growth). We were unable to detect any obvious alteration in phenotype of a strain carrying a disrupted copy of the ADHIII gene. 相似文献
103.
Stolina M Guo J Faggioni R Brown H Senaldi G 《Clinical immunology (Orlando, Fla.)》2003,109(3):347-354
The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens. 相似文献
104.
Evenomation by arachnids of the genus Loxosceles frequently results in disfiguring necrotic skin lesions. The cellular and molecular mechanisms which contribute to lesion development are incompletely defined but appear to involve participation of several pro-inflammatory mediators. We have recently observed that Loxosceles deserta venom induces the production of chemokines in human umbilical vein endothelial cells (HUVECs) and human pulmonary epithelial cells. In the present study we observed that Loxosceles deserta venom induces the expression of vascular endothelial growth factor (VEGF) in human keratinocytes but little in smooth muscle cells and none in pulmonary epithelial cells. A potent endothelial cell-specific mitogen, VEGF induces angiogenesis and vascular permeability in vivo. RNase protection assay data indicate that VEGF mRNA concentrations in keratinocytes are significantly increased at 2 h following venom exposure. These data suggest that keratinocyte-derived VEGF may contribute to the vasodilation, edema and erythema which occur following Loxosceles evenomation. 相似文献
105.
106.
We report on a 34-year-old developmentally disabled man referred to our clinic for evaluation of possible Prader-Willi syndrome on the basis of obesity and voracious appetite. Cytogenetic and molecular analysis revealed a 47, XYY karyotype and the presence of a trinucleotide repeat expansion resulting in fragile X syndrome. To our knowledge, this is the first report of concurrence of XYY and fragile X syndrome in the medical literature. Review of sex chromosome abnormalities associated with fragile X syndrome and phenotypic considerations are presented. 相似文献
107.
Karen Moss Heather Boon Peri Ballantyne Natasha Kachan 《BMC complementary and alternative medicine》2006,6(1):18-8
Background
New Canadian policy to regulate natural health products (NHPs), such as herbs and vitamins were implemented on January 1st, 2004. We explored complementary and alternative medicine (CAM) practitioners' perceptions of how the new regulations may affect their practices and relationships with patients/consumers. 相似文献108.
Childhood physical and sexual abuse and subsequent depressive and anxiety disorders for two American Indian tribes 总被引:1,自引:0,他引:1
Libby AM Orton HD Novins DK Beals J Manson SM;AI-SUPERPFP Team 《Psychological medicine》2005,35(3):329-340
BACKGROUND: This study examined the relationship of childhood abuse, both physical and sexual, with subsequent lifetime depressive and anxiety disorders--depression or dysthymia, post-traumatic stress disorder (PTSD), and panic or generalized anxiety disorder (GAD)--among American Indians (AIs). METHOD: Three thousand and eighty-four AIs from two tribes--Southwest and Northern Plains--participated in a large-scale, community-based study. Participants were asked about traumatic events and family history, and were administered standard diagnostic measures of depressive/anxiety disorders. RESULTS: Prevalence of childhood physical abuse was approximately 7% for both tribes. The Southwest tribe had higher prevalence of depressive and anxiety disorders, with rates of PTSD being the highest. Childhood physical abuse was significant in bivariate models of depressive/anxiety disorders, and remained so in the multivariate models. CONCLUSIONS: Childhood physical abuse was a significant predictor of all disorder groups for males in both tribes except for panic/GAD for the Northern Plains tribe in multivariate models; females showed a more varied pattern. Childhood sexual abuse did not significantly differ for males and females, and was an independent predictor of PTSD for both tribes, controlling for childhood physical abuse and other factors, and was significant for the other disorder groups only in the Southwest. Additional covariates that increased the odds of depressive/anxiety disorder, were adult physical or sexual victimization, chronic illness, lifetime alcohol or drug disorder, and parental problems with depression, alcohol, or violence. Results provided empirical evidence of childhood and later life risk factors and expanded the population at risk to include males. 相似文献
109.
Alan W Johnson Sandra J Potthoff Leslie Carranza Heather M Swenson Christine R Platt Jon R Rathbun 《Academic medicine》2006,81(3):252-256
The authors describe the development and impact of CLARION, a student-run organization at the University of Minnesota founded in 2001 and dedicated to furthering interprofessional education for health professions students. CLARION's student founders recognized that three recent reports from the Institute of Medicine will fuel significant changes in health professions education. Moreover, they deduced that targeted, interprofessional education in the preclinical years could provide fundamental skills and understanding needed to make today's patient care safer and more effective. By engaging health care professionals and faculty, CLARION creates and conducts extracurricular, interprofessional experiences for students that are reflective of the six IOM aims for health care. Student members are from four separate schools of the university's academic health center: medicine, nursing, pharmacy, and public health. The organization's capstone event, the Interprofessional Case Competition, challenges interprofessional teams of students to compete in conducting and presenting a root cause analysis of a fictitious sentinel event. The interprofessional organizational structure of the CLARION board models the kind of interprofessional equality needed to effectively solve problems in the health care system. The interaction among students from different health professions has led them to many new understandings about health care and the realization that many fundamental biases about other professions are firmly rooted in students before they enter the workplace. CLARION has enabled continued professional development of students, faculty, and practitioners, leading individual students to enhanced understanding of the health care system. It is a grassroots catalyst that has prompted faculty to reexamine traditional health professions curricula and look for ways to integrate more interprofessional opportunities into it. 相似文献
110.
The relative impact of early versus delayed visual experience on intersensory development was studied by manipulating the timing of visual experience of bobwhite quail (Colinus virginianus) embryos and hatchlings. Previous studies with quail chicks have revealed that: (1) Socially reared chicks require only maternal auditory cues to direct their social preferences in the first 2 days following hatching; (2) by 3 days following hatching chicks require both auditory and visual maternal cues to direct their social preferences; (3) chicks which have received unusually early visual experience as embryos require both auditory and visual cues by 24 hr following hatching, indicating an accelerated pattern of the emergence of intersensory functioning; and (4) chicks reared under conditions of attenuated social and visual experience continue to rely on matenal auditory cues alone at 4 days following hatching, indicating a decelerated pattern of early intersensory functioning. In the present study, quail chicks that received both early visual experience as embryos and delayed visual experience as hatchlings exhibited a pattern of both auditory and visual responsiveness like that seen in normally reared chicks. These results indicate that, at least under the present experimental conditions, the influence of early and delayed visual experience on perinatal perceptual development appears to be relatively comparable in effect © 1993 John Wiley & Sons, Inc. 相似文献