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991.
Fordyce Wilbert E. Brockway Jo Ann Bergman James A. Spengler Daniel 《Journal of behavioral medicine》1986,9(2):127-140
Back-pain patients with onset in the preceding 1–10 days and comparable on a back examination were randomly assigned to traditional management (A regimen) and behavioral treatment methods (B regimen). Patients were compared at 6 weeks and 9–12 months on a set of Sick/Well scores derived from patient reported vocational status (V), health-care utilization (HCU), claimed impairment (CI), and pain drawings (D) and on two measures of activity level. No differences were found at 6 weeks, but at 9–12 months, A-group S's were more sick. No A/B differences were found on activity-level measures. Group A S's showed significant increases in claimed impairment from preonset to follow-up, whereas Group B S's had returned at follow-up to preonset levelsA special acknowledgment is made to Darnel Rock, M.S., now of the Department of Psychology, Vanderbilt University, for his major contributions to the organization and analysis of the data of this study. 相似文献
992.
Transformation of B and non-B cell lines with the 2,4,6,-trinitrophenyl (TNP)-specific immunoglobulin genes 总被引:2,自引:0,他引:2
The rearranged mu and kappa genes from the 2,4,6-trinitrophenyl (TNP)-specific hybridoma Sp6 have been introduced into B cells from three different stages of differentiation as well as 5 non-B cell lines to determine the levels and modes of immunoglobulin (Ig) gene expression. In pre-B cells transformed with the mu and kappa genes, low levels of Sp6-specific mu RNA were produced and approximately 210-fold less mu and 800-fold less kappa proteins were produced than in the hybridoma Sp6. The Ig proteins were present intracellularly, but were not detected on the cell membrane. In mature surface sIg+ B cell transformants, higher levels of mu Sp6 and kappa Sp6 proteins and RNA were produced than in the pre-B cell transformants (12 X mu, 70 X kappa). These transformants displayed the mu Sp6 and kappa Sp6 proteins on the cell membrane and also secreted the transfected Ig product. Plasma cell transformants produced the highest amounts of mu Sp6 and kappa Sp6 proteins. These transformants secreted pentameric IgM but did not display detectable amounts of these proteins on the cell membrane. T cell and one fibroblast transformant produced Ig as normal sized mu Sp6 and kappa Sp6 proteins. All other mu Sp6 and kappa Sp6 non-B cell transformants (melanoma, teratoma and macrophage) failed to produce enough Ig to determine whether the Ig proteins were of the correct molecular weights. The T cell and fibroblast transformants that produced Ig proteins did not secrete or display detectable Ig on the cell membrane. The expression of Ig did not inhibit the expression of the T cell antigen Thy-1 in the T cell transformants. 相似文献
993.
Partial trisomy 6p and partial monosomy 9p from a de novo translocation 46, XY, -9, + DER(9)T(6:9)(p211:p24) 总被引:1,自引:0,他引:1
Melanie S. Eden James W. Thelin Karen Michalski Joyce A. Mitchell 《Clinical genetics》1985,28(5):375-384
This report describes an adult male with a partial trisomy 6p(p211-pter) and a partial monosomy 9p(9p24-pter) resulting from a de novo unbalanced translocation. This patient does not show the classical featured of the 9p partial monosomy syndrome, thus disputing the claim of Hoo et al. (1982) that 9p24 is the critical segment for the monosomy syndrome. Partial trisomy for 6p has only been previously reported in children. In addition to the chromosomal anomalies, the patient has autosomal recessive spinal muscular atrophy with a different age of onset than two affected sibs. Finally, he shows unusual audiologic and ophthalmologic signs nor previously reported as part of the 9p monosomy or 6p trisomy syndromes. 相似文献
994.
P. Bryant Chase Donald A. Martyn James D. Hannon 《Journal of muscle research and cell motility》1994,15(2):119-129
Summary To examine the mechanism by which aluminiofluoride, a tightly binding analogue of inorganic phosphate, inhibits force in single, chemically skinned fibres from rabbit psoas muscle, we measured the Ca2+-dependence of the kinetics of inhibitor dissociation and the kinetics of actomyosin interactions when aluminiofluoride was bound to the crossbridges. The relation between stiffness and the speed of stretch during small amplitude ramp stretches (< 5 nm per h.s.) was used to characterize the kinetic properties of crossbridges attached to actin; sarcomere length was assessed with HeNe laser diffraction. During maximum Ca2+-activation at physiological ionic strength (pCa 4.0, 0.2 m /2), stiffness exhibited a steep dependence on the rate of stretch; aluminiofluoride inhibition at pCa 4.0 (0.2 m /2) resulted in an overall decrease in stiffness, with stiffness at high rates of stretch (103–104 nm per h.s. per s) being disproportionately reduced. Thus the slope of the stiffness-speed relation was reduced during aluminiofluoride inhibition of activated fibres. Relaxation of inhibited fibres (pCa 9.2, 0.2 m /2) resulted in aluminiofluoride being trapped and was accompanied by a further decrease in stiffness at all rates of stretch which was comparable to that found in control relaxed fibres. In relaxed, low ionic strength conditions (pCa 9.2, 0.02 m /2) which promote weak crossbridge binding, stiffness at all rates of stretch was significantly inhibited by aluminiofluoride trapped in the fibre. To determine the Ca2+-dependence of inhibitor dissociation, force was regulated independent of Ca2+ using an activating tropinin C (aTnC). Results obtained with aTnC-activated fibres confirmed that there is no absolute requirement for Ca2+ for recovery from force inhibition by inorganic phosphate analogues in skinned fibres; the only requirement is thin filament activation which enables active crossbridge cycling. These results indicate that aluminiofluoride preferentially inhibits rapid equilibrium or weak crossbridge attachment to actin, that aluminiofluoride-bound crossbridges attach tightly to the activated thin filament, and that, at maximal (or near-maximal) activation, crossbridge attachment to actin prior to inorganic phosphate analogue dissociation is the primary event regulated by Ca2+. 相似文献
995.
Peter S. Lee Richard M. Schreck Bradley A. Hare James J. McGrath 《Annals of biomedical engineering》1994,22(1):120-125
Tunable diode laser spectrometry was used to measure breath carbon monoxide (CO) concentrations in nonsmoking subjects. Corresponding
blood carboxyhemoglobin (COHb) saturations between physiological levels and levels after 1 and 8 hours exposure to 9 ppm CO,
the maximum permissible concentration in the air under federal regulations, were also determined. A good linear correlation
between breath CO and blood COHb saturation for low levels representing ambient conditions was established, with a correlation
coefficient better than 0.999 for the means and 0.945 for the individual data points. Similar studies on the other compounds
of concern are also possible using tunable diode laser spectrometry, requiring only a breath sample and with no sample preparation.
This technique will facilitate fast, noninvasive environmental health effect and biomedical studies. 相似文献
996.
997.
998.
Influenza pandemic planning is a complex, multifactorial process, which involves public health authorities, regulatory authorities, academia and industry. It is further complicated by the unpredictability of the time of emergence and severity of the next pandemic and the effectiveness of influenza epidemic interventions. The complexity and uncertainties surrounding pandemic preparedness have so far kept the various stakeholders from joining forces and tackling the problem from its roots. We developed a mathematical model, which shows the tangible consequences of conceptual plans by linking possible pandemic scenarios to health economic outcomes of possible intervention strategies. This model helps to structure the discussion on pandemic preparedness and facilitates the translation of pandemic planning concepts to concrete plans. The case study for which the model has been used shows the current level of global pandemic preparedness in an assumed pandemic scenario, the health economic implications of enhanced pandemic vaccine supply and the importance of cell culture-based influenza vaccine manufacturing technologies as a tool for pandemic control. 相似文献
999.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12
Background
Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. 相似文献1000.