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991.
We examined developmental differences in smooth pursuit eye tracking proficiency in a large sample of preadolescent, adolescent, and adult males. Smooth pursuit was quantified using general measures of oculomotor functioning and by examining the frequency and dynamic characteristics of specific saccadic events. Examination of age effects using general measures indicated that, by late adolescence, the smooth pursuit system reached adult levels of functioning. No significant differences were found between the adolescent and adult groups on most global measures. However, both groups had better eye tracking than the preadolescent group, suggesting that during preadolescence the oculomotor system is still developing and is not yet capable of optimal performance. Examination of the frequency and dynamic characteristics of the saccadic events yielded additional information regarding the nature of the smooth pursuit eye tracking differences of the three age groups. 相似文献
992.
Waters WF Hurry MJ Binks PG Carney CE Lajos LE Fuller KH Betz B Johnson J Anderson T Tucci JM 《Behavioral sleep medicine》2003,1(2):81-101
This investigation compared progressive muscle relaxation plus cognitive distraction (PMR/CD), hypothesized to better improve sleep onset, versus sleep restriction and stimulus control (SR/SC), hypothesized to better improve sleep maintenance, versus a flurazepam (Dalmane) positive contrast condition (MED) and a sleep hygiene education minimal treatment control condition (SHE). Participants with chronic insomnia (N = 53), completed 2 baseline weeks of sleep diaries, and were randomly assigned to a treatment group for 2 more weeks. In the second phase, PMR/CD participants were assigned to 2 weeks of PMR/CD + SR/SC + SHE while SHE participants continued SHE. Results indicated that PMR/CD had greater effect upon sleep onset than SR/SC and SHE, SR/SC had greater effect on sleep maintenance than PMR/CD, and MED was better than the other treatments. In the second phase, the treatment package produced modest additional improvements and SHE performed superior to expectations. 相似文献
993.
994.
Brown M Gustafson M Saldãna S Baradaran A Miller H Halonen M 《Human immunology》2004,65(11):1336-1343
Human decidua has been shown to produce a number of cytokines. We hypothesized that decidual cytokine production influences cord blood mononuclear cell (CBMC) cytokine production and that cytokine profiles of decidua from allergic women differ from those of decidua from nonallergic women. Using enzyme-linked immunosorbent assay, we measured unstimulated and concanavalin A/phorbol myristate acetate-stimulated production of interleukin-4 (IL-4), IL-5, IL-10, IL-13 and interferon- gamma (IFN-gamma) by decidual explants from 59 healthy women delivered by unlabored cesarean section and from corresponding CBMCs in 39 of the 59. Except for IL-10, there was little or no unstimulated cytokine production. There was a strong correlation between stimulated decidual and stimulated CBMC IFN-gamma production (p = 0.01). In allergic women the ratio of IL-13 to IL-4 production was increased in stimulated explants (p = 0.03). Stimulated CBMCs from infants of allergic mothers were more likely to produce detectable levels of IL-5 than those from infants of nonallergic mothers (p = 0.04) and had a tendency toward higher IL-13 levels as well (p = 0.07). These results suggest that maternal and fetal IFN-gamma production is closely linked and that maternal allergy appears to influence cytokine production in the neonate for IL-5 and possibly IL-13. 相似文献
995.
Osteopetrosis, a metabolic bone disease characterized by a generalized sclerosis of the skeleton, is inherited as an autosomal recessive in a number of mammalian species. The pathogenesis of congenital osteopetrosis is mediated by a reduction in bone resorption as a result of decreased osteoclast function. This hypothesis is based on both functional and structural evidence of reduced bone resorption in all mutations examined to date. The present study examined the histology of cartilage and bone, the ultrastructure of osteoclasts, and the morphology of mineralized bone surfaces in a lethal osteopetrotic mutation, the osteosclerotic (oc) mouse. Histologically, epiphyseal cartilage growth plates, especially the hypertrophic zone, are markedly thickened in oc mice and metaphyses contain excessive osteoid, features characteristic of rickets. Transmission electron microscopy revealed that less than one-quarter of osteoclasts in oc mice demonstrated evidence of ruffled border formation compared with three-quarters of the osteoclasts in normal littermates. In mutants, ruffled borders were less elaborate and cytoplasmic processes penetrated into bone surfaces, suggesting that bone may be removed by mechanical rather than by enzymatic means. There was little morphological evidence of cartilage degradation and broad laminae limitantes persisted in mutants. Mineralized surfaces that undergo resorption in normal mice showed no evidence of bone resorption by scanning EM in mutants. The presence of a rachitic condition, the observations of reduced bone resorption, and the possible contribution of undermineralized matrices to decreased bone resorption are charcteristics of the osteosclerotic mutation which suggest that it is a unqiue csteopetrotic mutant in which to study both the development and regulation of skeletal metabolism. 相似文献
996.
Deepika D'Cunha Burkardt Anna Zachariou Chey Loveday Clare L. Allen David J. Amor Anna Ardissone Siddharth Banka Alexia Bourgois Christine Coubes Cheryl Cytrynbaum Laurence Faivre Gerard Marion Rachel Horton Dieter Kotzot Guillermo Lay‐Son Melissa Lees Karen Low Ho‐Ming Luk Paul Mark Allyn McConkie‐Rosell Marie McDonald John Pappas Christophe Phillipe Deborah Shears Brian Skotko Fiona Stewart Helen Stewart I Karen. Temple Frederic T. Mau‐Them Ricardo A. Verdugo Rosanna Weksberg Yuri A. Zarate John M. Graham Katrina Tatton‐Brown 《American journal of medical genetics. Part A》2019,179(10):2049-2055
997.
Radioprotective efficacy and acute toxicity of 5-androstenediol after subcutaneous or oral administration in mice 总被引:3,自引:0,他引:3
Whitnall MH Wilhelmsen CL McKinney L Miner V Seed TM Jackson WE 《Immunopharmacology and immunotoxicology》2002,24(4):595-626
We previously showed that one subcutaneous (sc) injection of 5-androstene-3beta,17beta-diol (AED) stimulated the innate immune system in mice and prevented mortality due to hemopoietic suppression after whole-body ionizing irradiation with gamma rays. In the present study, we tested whether there was any significant toxicity in mice that might hinder development of this steroid for human use. There were no indications of toxicity in chemical analyses of serum after sc doses as high as 4000 mg/kg. At this dose, 2 of 54 mice died when given AED alone. When 4800 mg/kg was given orally, no deaths resulted. The only adverse findings attributed to AED administration were 1) a moderate elevation of granulocytes in abdominal organs and fat after sc injections of 320 mg/kg; and 2) occasional wasting of skin over the injection site in female B6D2F1 but not male C3H/HeN mice. Significant weight loss (6%) was observed after sc injections of 320 mg/kg but not 160 or 80 mg/kg. When male C3H/HeN mice were injected sc with AED at doses of 0-200 mg/kg 24 h before whole body gamma-irradiation (9 Gy), a significant improvement in survival was observed at doses as low as 5 mg/kg. Oral administration of AED produced significant survival enhancement at a dose of 1600 mg/kg. We conclude that the radioprotective efficacy of AED is accompanied by low toxicity.Androst-5-ene-3 beta, 17 beta-diol; Ionizing radiation; Experimental radiation injuries; Toxicity; Clinical chemistry; Histopathology 相似文献
998.
The Bioperl toolkit: Perl modules for the life sciences 总被引:36,自引:4,他引:36
Stajich JE Block D Boulez K Brenner SE Chervitz SA Dagdigian C Fuellen G Gilbert JG Korf I Lapp H Lehväslaiho H Matsalla C Mungall CJ Osborne BI Pocock MR Schattner P Senger M Stein LD Stupka E Wilkinson MD Birney E 《Genome research》2002,12(10):1611-1618
The Bioperl project is an international open-source collaboration of biologists, bioinformaticians, and computer scientists that has evolved over the past 7 yr into the most comprehensive library of Perl modules available for managing and manipulating life-science information. Bioperl provides an easy-to-use, stable, and consistent programming interface for bioinformatics application programmers. The Bioperl modules have been successfully and repeatedly used to reduce otherwise complex tasks to only a few lines of code. The Bioperl object model has been proven to be flexible enough to support enterprise-level applications such as EnsEMBL, while maintaining an easy learning curve for novice Perl programmers. Bioperl is capable of executing analyses and processing results from programs such as BLAST, ClustalW, or the EMBOSS suite. Interoperation with modules written in Python and Java is supported through the evolving BioCORBA bridge. Bioperl provides access to data stores such as GenBank and SwissProt via a flexible series of sequence input/output modules, and to the emerging common sequence data storage format of the Open Bioinformatics Database Access project. This study describes the overall architecture of the toolkit, the problem domains that it addresses, and gives specific examples of how the toolkit can be used to solve common life-sciences problems. We conclude with a discussion of how the open-source nature of the project has contributed to the development effort. 相似文献
999.
J. Mark Ebertz Jeanne M. Hermens J. Clifford McMillan Hideo Uno Carol Hirshman Jon M. Hanifin 《Inflammation research》1986,18(5-6):455-462
Intravenous administration of morphine sulfate often produces urticarial and hypotensive reactions associated with elevations in plasma histamine. The source of this histamine and mechanisms controlling its release are poorly understood. Previous studies of morphine-induced histamine release compared human leukocytes to rat peritoneal mast cells. The effects of morphine on human cutaneous mast cells has not been examined. We studiedin vitro histamine release from human basophils and human skin preparations containing cutaneous mast cells to evaluate their relative, contribution to the pharmacologic effects of morphine.Human skin mast cell preparations showed dosedependent histamine release over a morphine concentration range of 1.5×10–5 to 4.5×10–3
M, with peak release occurring at 5×10–4
M, with peak release occurring at 5×10–4
M. Clinically, morphine sulfate is usually injected as a 1.5×10–2
M solution. Histamine release was calcium dependent and equivalent to that obtained with 3 and 10 mM strontium. Morphologic examination revealed degranulation and exocytosis occurring in morphine-stimulated tissue but not in specimens exposed to buffer alone. Lactate dehydrogenase levels did not increase following morphine incubation, thus supporting a noncytolytic mechanism of histamine release.Basophils, in contrast, showed no significant histamine release from exposure to morphine up to 10–2
M. Concanavalin A, as a positive control in these same preparations, produced a mean histamine release of 21.0%.Our studies indicate distinct functional differences between human skin mast cell and human blood basophil responses to morphine sulfate. We conclude that the cutaneous and systemic reactions to morphine sulfate probably result from the release of histamine from mast cells rather than from basophils.This study was supported by: National Institutes of Health Grants 2-T32 AMO7153, 5-RO1 AI18615, AI 15557, HL 25831, American Society of Anesthesiologists Starter Grant 1283, and a grant from the Bramble Foundation. 相似文献
1000.
Intrathymic (i.t.) injection of islet cells or whole islets retards development of insulin dependent diabetes mellitus (IDDM) in spontaneous animal models of the disease. Protection of 4-week-old prediabetic NOD/Lt female mice from subsequent IDDM development was specific for the it route of administration since intraperitoneal injection of an equal number of syngeneic islets failed to retard IDDM. The protective effect of i.t. injection of islet cells was compared with the effect of i.t. injection of syngeneic peritoneal exudate cells, NIT-1 cells, bovine serum albumin (BSA), ABBOS peptide, a 52 kDa islet cell membrane protein, various synthetic peptides from human glutamic acid decarboxylase (GAD) and a Coxsackievirus B4-derived peptide with homology to GAD. Interestingly, only a GAD-derived peptide containing sequence homology to Coxsackievirus B4, and the corresponding Coxsackievirus B4-derived peptide, delayed IDDM onset. To establish the immunological mechanism underlying the reduced IDDM incidence following i.t. injection of islet cells, adoptive transfer of splenic leukocytes into NOD-scid/scid mice was performed. Splenic leukocytes from i.t.-injected non-diabetic females transferred IDDM into NOD-scid/scid recipients, but more slowly than splenocytes from unmanipulated, diabetic (control) donors. Co-transfer of 1:1 mixtures of splenic leukocytes from it islet-injected (and diabetes-free) NOD/Lt females and from untreated NOD/Lt diabetic donors produced IDDM as rapidly as splenocytes from diabetic donors injected alone. Hence, any peripheral suppression generated in i.t.-protected females was not sufficiently strong to prevent IDDM transfer by committed T-effector cells from the diabetic donors. Studies in progress suggest that it exposure to islet cell autoantigens mediates IDDM protection by retarding the activation of islet autoreactive effector cells. In summary, although the mechanisms underlying IDDM retardation by introduction of islet cell autoantigens into the thymic micro-environment are not well understood, the method provides a useful bioassay for establishing the specific pathogenic potential of 'candidate' islet autoantigens. 相似文献