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81.
In this study we examined the effect of mitogens and epidermal cells in inducing a Sezary cell morphology in normal peripheral blood lymphocytes. Peripheral blood mononuclear cells from six healthy volunteers were stimulated with the mitogens phytohemaglutinin and concanavalin A, and also cocultivated with human epidermal cell cultures. Incubation times with mitogens and epidermal cells were four days and stimulation of the lymphocytes by mitogens was confirmed by standard 3H-thymidine uptake. Standard transmission electron microscopy showed that in the mitogen-driven system 20% to 60% (33 +/- 15%) and in the epidermal cell-driven system 5% to 15% (8 +/- 4%) of the lymphoid cells exhibited mild to moderate indentation of the nuclei with nuclear contour indices (NCI) of 4.6 to 6.5 but no Sezary cells were observed (cells with NCI greater than 6.5 and up to 19.2). In the mitogen- stimulated preparation 2% to 5% (3 +/- 1%) of the lymphoid cells showed nuclear multilobulation resembling the cells seen in adult T cell lymphoma/leukemia. Incubation of mononuclear cells for longer periods of up to 4 weeks with mitogens and exogenous IL-2 resulted in no further morphologic changes. Using an indirect immunogold technique at the electron microscopic level, the cells showing nuclear indentation or lobulation were shown to bear both T helper (CD4) and T suppressor (CD8) cell phenotypes in a similar ratio to the total numbers of T helper and T suppressor cells present. Mitogens and epidermal cells are thus not able to induce a morphologic change to Sezary cells in normal peripheral blood lymphocytes. 相似文献
82.
The medical records of 19 patients with acquired immune deficiency syndrome (aids) were reviewed in an attempt to estimate their health care costs. The patients were all male, members of high risk groups and diagnosed between April 1985 and February 1988. Twelve of the patients died; they lived a mean of 240 days (range 0 to 580) after diagnosis, were admitted three times (range one to six) to hospital for 65 total days (range one to 148) for a cost per patient of $33,721 (range $2,768 to $64,981) for inpatient care. They made five (range zero to 25) office visits per patient costing $196 per patient (range $0 to $4,999) for outpatient care. The seven survivors (one was lost to follow-up) have lived 375 days (range 186 to 551) since diagnosis, have been admitted to hospital two times (range zero to seven) for 30 total days (range zero to 86) for a total cost per patient of $14,223 (range $0 to $39,410) for inpatient care. They have made 11 office/emergency room visits (range zero to 46) costing in total $4322 (range $0 to $13,605) for outpatient care. The total expenditure was $546,332 ($28,754 per patient), of which total fees to physicians were $37,210 (6.8%), and estimated costs of laboratory tests $117,917 (21.6%), drugs $36,930 (6.7%), and medical imaging $20,794 (3.8%). Patients now deceased cost $416,445 (mean $34,704 per patient), accounting for 76.2% of overall expenditures. The average medical/surgical and drug costs per patient day in hospital were greater for aids patients than for the average medical/surgical patient in the authors' institution. 相似文献
83.
S R Jones J Pannell J Barks Y A Yanchick T Bratton R Browne E McRee J W Smith 《The American journal of the medical sciences》1977,273(1):79-85
The effect of an educational program on the use of antibiotics was studied in a university-affiliated Veterans Administration Hospital. Following an initial survey of antibiotic usage, educational presentations of the collected data were made to the hospital staff which included specific prescribing errors and alternative recommendations. Then, another survey was conducted. Measurable changes following the educational presentations were limited to decreasing costs of unjustified antibiotic use. An effect was noted in decreasing unjustified use of antibiotics in prophylactic situations, but this remained the most common misuse. Thus, an educational program directed at specific prescribing errors produced little noticeable effect on the use of antibiotics in a university-affiliated hospital. The study indicates that more direct measures, such as control of use of particular antibiotics, may be required to produce a meaningful change in prescribing practices. 相似文献
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86.
Browne Julia Cather Corinne Zvonar Vanya Thayer Katherine Skiest Hannah Arntz Diana Kritikos Katherine Schnitzer Kristina Brown Hannah Evins A. Eden Donovan Abigail 《Community mental health journal》2021,57(5):864-871
Community Mental Health Journal - The mortality disparity for persons with schizophrenia spectrum disorders (SSDs) due to cardiovascular disease is a devastating problem. Many risk factors are... 相似文献
87.
Kristina M. Holsgrove Martial Duchamp M. Sergio Moreno Nicolas Bernier Aaron B. Naden Joseph G. M. Guy Niall Browne Arunava Gupta J. Marty Gregg Amit Kumar Miryam Arredondo 《RSC advances》2020,10(47):27954
It is now well-established that boundaries separating tetragonal-like (T) and rhombohedral-like (R) phases in BiFeO3 thin films can show enhanced electrical conductivity. However, the origin of this conductivity remains elusive. Here, we study mixed-phase BiFeO3 thin films, where local populations of T and R can be readily altered using stress and electric fields. We observe that phase boundary electrical conductivity in regions which have undergone stress-writing is significantly greater than in the virgin microstructure. We use high-end electron microscopy techniques to identify key differences between the R–T boundaries present in stress-written and as-grown microstructures, to gain a better understanding of the mechanism responsible for electrical conduction. We find that point defects (and associated mixed valence states) are present in both electrically conducting and non-conducting regions; crucially, in both cases, the spatial distribution of defects is relatively homogeneous: there is no evidence of phase boundary defect aggregation. Atomic resolution imaging reveals that the only significant difference between non-conducting and conducting boundaries is the elastic distortion evident – detailed analysis of localised crystallography shows that the strain accommodation across the R–T boundaries is much more extensive in stress-written than in as-grown microstructures; this has a substantial effect on the straightening of local bonds within regions seen to electrically conduct. This work therefore offers distinct evidence that the elastic distortion is more important than point defect accumulation in determining the phase boundary conduction properties in mixed-phase BiFeO3.The localized crystallography of conducting and non-conducting phase boundaries in mixed-phase BiFeO3 is directly compared using scanning transmission electron microscopy techniques.The complexity of electrical conductivity in domain walls in BiFeO3 (and in ferroics in general) is as multifaceted as ever. Various influences such as point defect accumulation, octahedral rotations, magnetic interactions and electrostatic discontinuities are thought to be possible mechanisms at play,1–8 either alone or in combination. The research area of domain wall conductivity is currently flourishing and the view that domain walls offer exciting prospects in terms of engineering systems in which the domain walls act as distinct identities to the domains which they separate is now widely accepted. We believe that it is pertinent timing to address a lack of experimental investigations providing meaningful direct comparison of the localised crystallography and defect structure responsible for observed enhanced electrical conductivity. This study is stimulated by the interesting discoveries of conductive phase boundaries, specifically, in mixed-phase BiFeO3.9,10 By tuning the local populations of the tetragonal-like (T) and rhombohedral-like (R) phases in BiFeO3 thin films via electric and stress fields, we demonstrate that electrical conductivity along phase boundaries is significantly greater after stress-writing. We probe the key crystallographic differences between the R–T boundaries created via stress, compared to those already present in the as-grown microstructures, to disentangle the mechanism determining electrical conduction in mixed-phase BiFeO3.The growth of BiFeO3 on substrates enforcing a large in-plane compressive strain drives the formation of monoclinic phases that are approximately rhombohedral (R) and tetragonal (T). Similar to materials such as PbZr0.53Ti0.47O3 that straddle a morphotropic phase boundary, highly strained BiFeO3 can readily undergo phase transitions between the R and T phases (and vice versa). The high-strain T phase exhibits a tetragonal-like symmetry (almost P4mm) with a c/a ratio of ∼1.2; the Fe displacement towards one of the apical oxygens along [001]pc results in fivefold oxygen coordinated Fe, and an enhanced polarisation roughly 1.5 times that of the bulk single crystal.7,11 The R phase, on the other hand, resembles the rhombohedral bulk phase (almost R3c), where the Fe is octahedrally coordinated, with a ferroelectric distortion along the pseudocubic [111]pc axis, and antiferrodistortive rotations of the FeO6 octahedra around [111]pc occur. The crystal structure and misfit strain associated with the native (as-grown) R and T phases is reported elsewhere, both theoretically12–15 and experimentally,6,7,16–21 making it well-known that the ferroelectric and the antiferrodistortive degrees of freedom in mixed-phase BiFeO3 set it apart from other typical perovskites. Notably, despite the ample evidence provided on phase reversal and characterisation of the as-grown phases, most of the literature (especially regarding electric field cycling of the mixed-phase state) has been primarily concerned with X-ray diffraction (XRD) i.e. global measurements that will not necessarily pick up on the more subtle, atomic-scale aspects of structure local to the phase boundaries. The importance of the study described herein resides in the uniqueness of creating microstructures such that both the as-grown and stress-induced R–T phase boundaries can be included within one single cross-sectional transmission electron microscopy (TEM) lamella; this gives the best possible scenario to allow meaningful direct comparison of the localised crystallography and defect structure responsible for the observed enhanced electrical conductivity found at stress-induced phase boundaries. 相似文献
88.
J. Chung A. Kordzadeh I. Prionidis Y. Panayiotopoulos T. Browne 《Journal of Ultrasound》2015,18(2):91-99
Purpose
The purpose of this systematic review is to assess the accuracy of contrast-enhanced ultrasound (CEUS) to computed tomography angiography (CTA) for the detection of endoleaks within EVAR surveillance program.Material and methods
A systematic review in Pubmed, Embase and Cochrane database was performed. Articles assessing diagnostic accuracy and comparative modality (CTA vs. CEUS) for endoleaks in adult patients within surveillance programs were retrieved. Methodological assessment was performed, using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tools. The sensitivity and specificity of data were extracted and statistical analysis was performed using MetaDiSc version 1.4.Results
Eight articles were found eligible (n = 454 patients). The pooled sensitivity of CEUS at detecting endoleak is 0.914 (CI 0.866–0.949) and pooled specificity is 0.782 (CI 0.741–0.820).Conclusion
The CEUS with its dynamic nature and longer scanning window demonstrated to be a highly sensitive modality for endoleak detection in comparison to CTA in delayed endoleaks type II. 相似文献89.
90.
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro. 相似文献