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排序方式: 共有479条查询结果,搜索用时 15 毫秒
461.
PS Wells MJ Kovacs J Bormanis MA Forgie D Goudie B Morrow J Kovacs 《Canadian Metallurgical Quarterly》1998,158(16):1809-1812
BACKGROUND: The outpatient treatment of patients with deep vein thrombosis and pulmonary embolism using low-molecular-weight heparin has the potential to reduce health care costs, but it is unclear if most patients with deep vein thrombosis and pulmonary embolism can be treated as outpatients. In the published studies, more than 50% of patients were excluded from outpatient treatment for reasons such as comorbid conditions, short life expectancy, concomitant pulmonary embolism, and previous deep vein thrombosis, and many patients were not treated entirely at home. We sought to determine if expanding patient eligibility for the outpatient treatment of deep vein thrombosis and pulmonary embolism affects the safety and effectiveness of the treatment, and to determine if patient self-injection compared with injections administered by a homecare nurse affected these outcomes. PATIENTS AND METHODS: We treated as outpatients all patients with deep vein thrombosis and pulmonary embolism, except for those with massive pulmonary embolism, high risk for major bleeding or an active bleed, phlegmasia, and patients hospitalized for reasons that prevented discharge. We compared 2 models of outpatient care to determine feasibility, safety, and efficacy. Both models involved nurse managers who provided daily patient contact and ongoing treatment; however, in one model the patients were taught to inject themselves and in the other model homecare nurses administered the injections. We expanded the population of patients eligible for outpatient treatment by including many patients not treated at home in previous studies. Most patients in our study were treated with dalteparin sodium, 200 U/kg every 24 hours, for a minimum of 5 days. Therapy with warfarin sodium was started on the day of diagnosis or the following day. Patients were followed up for 3 months to determine rates of recurrent venous thromboembolism, bleeding, and death. RESULTS: In this study, 194 (83%) of 233 consecutive patients were deemed eligible and treated as outpatients. Of the 39 patients who did not receive home therapy, 20 had concomitant medical problems responsible for their admission or were already inpatients, 6 had massive pulmonary embolism, 6 refused to pay for the dalteparin therapy, 4 had active bleeding, and 3 had phlegmasia cerulea dolens, which required treatment with intravenous narcotics for pain control. More than 184 (95%) of the 194 patients were treated entirely at home. There was no significant difference (P>.99) in the rate of recurrent venous thromboembolic events between the patients who were injected by homecare nurses (3/95 [3.2%]) and those who injected themselves (4/99 [4.0%]). Combining the 2 models, the overall recurrent event rate was 3.6% (95% confidence interval, 1.5%-7.4%). Similarly, there were no significant differences in rates of major hemorrhage (2/95 vs 2/99; P>.99), minor hemorrhage (8/95 vs 2/99; P = .06), and death (6/95 vs 8/99; P = .63). The overall rate of major hemorrhage was 2.0% (95% confidence interval, 0.6%-5.2%). CONCLUSIONS: We demonstrate that more than 80% of patients at our tertiary care hospital could be treated at home using 1 of the 2 models of care we describe. Our results demonstrate that patients can safely and effectively perform home self-injection under the supervision of a hospital-based nurse. Injections at home by a homecare nurse are similarly effective. Our overall rates of recurrent venous thromboembolism, bleeding, and death are at least as favorable as those previously reported despite using 1 dose per day of dalteparin for most patients. 相似文献
462.
B Lundgren JA Kovacs L Mathiesen JO Nielsen JD Lundgren 《Canadian Metallurgical Quarterly》1993,25(4):515-520
A series of eight new N-hydroxy-N'-aminoguanidine (HAG) Schiff bases [ArCH = NNHC(= NH)NHOH.tosylate] was synthesized as potential antitumor agents through the inhibition of the enzyme ribonucleotide reductase (EC 1.17.4.1). Five of the HAG derivatives (LK02 through LK06) were designed to contain an orthohydroxy group on the phenyl ring of ArCH = to increase the stability of the Schiff base formed. In addition, two compounds with a substituted quinoline [LK10; ArCH = (4-hydroxy-7-trifluoromethylquinolin-3-yl)methylene] or isoquinoline (LK11; ArCH = (5-nitroisoquinolin-1-yl)methylene] moiety were synthesized through multiple-step reactions involving reduction and/or oxidation. The IC50 values of the newly synthesized HAG Schiff bases were determined against human leukemic CCRF-CEM/0 cells in culture. The IC50 values of two previously reported HAG derivatives [ATL25; ArCH = (5-nitro-isoquinolin-1-yl)methylene] and [LW02; ArCH = 2-hydroxy-3-allyl-benzylidene)] were also determined for the first time against CCRF-CEM/0 cells. Among the compounds tested, LK11 was found to be the most potent (IC50, 2.95 +/- 0.1 microM) and the 4-methoxy-2-hydroxyphenyl derivative (LK02) to be the least potent (IC50, 121 +/- 16 microM). LK11 was about 15-fold more potent against CCRF-CEM/0 cells compared to the parent compound hydroxyguanidine sulfate (IC50, 46 +/- 7.1 microM) and was about 32 times more potent than LK10 (IC50, 97.6 +/- 0.9 microM). LK11 in combination was incubated in sequence with cytarabine (ara-C) at various molar ratios against CCRF-CEM/0 cells for 48 hr. The results were analyzed using both the isobologram and the median-effect methods.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
463.
K Thapar K Kovacs BW Scheithauer L Stefaneanu E Horvath PJ Pernicone D Murray ER Laws 《Canadian Metallurgical Quarterly》1996,38(1):99-106; discussion 106-7
Although histologically benign, one-third of all pituitary tumors will be invasive of surrounding structures. In this study, the relationship between the proliferative activity in pituitary adenomas and their invasiveness was investigated. Invasion was defined as gross, operatively or radiologically apparent infiltration of dura or bone. Using the recently developed MIB-1 monoclonal antibody, which recognizes the Ki-67 cell cycle-specific nuclear antigen, the growth fractions of 37 noninvasive adenomas, 33 invasive adenomas, and 7 primary pituitary carcinomas were determined. All tumors were fully classified by histology, immunohistochemistry, and electron microscopy. The mean Ki-67 -derived growth fractions for noninvasive adenomas, invasive adenomas, and pituitary carcinomas were 1.37 +/- 0.15%, 4.66 +/- 0.57%, and 11.91 +/- 3.41%, respectively (mean +/- standard error of the mean). An analysis of variance and then individual pairwise comparisons confirmed significant differences in the mean Ki-67 labeling index between each of the three tumor groups (P < 0.01). The mean growth fraction of hormonally active pituitary adenomas (3.25 +/- 0.26%) was significantly higher than that for nonfunctioning adenomas (2.06 +/- 0.23%) (P = 0.03). Establishing a threshold labeling index of 3% served to distinguish invasive from noninvasive adenomas with 97% specificity and 73% sensitivity and was associated with positive and negative predictive values of 96 and 80%, respectively. Although invasive pituitary tumors exhibited significantly higher growth fractions than did noninvasive tumors, there were individual exceptions, indicating that in a subpopulation of invasive pituitary tumors, factors other than proliferative activity determine invasive potential. 相似文献
464.
We have previously shown that subsurface particulate monolayers form rather generally when inorganic materials are appropriately deposited onto softenable organic polymer substrates. Here we analyse, in terms of the surface free energies, the thermodynamic stability on soft substrates of the various conceivable subsurface structures versus the possible above-surface configurations. For both rigid preformed particles and flexible growing clusterd (as occur in vacuum deposition), the tendency for complete immersion is determined by the same inequality among the various surface and interfacial tensions. Estimates of these parameters predict a completely embedded structure to be thermodynamically favourable for most inorganic materials on organic polymer substrates, with generally a partially embedded structure predicted for organic materials. Although, with vacuum deposition of the particle material, subsurface structure formation is often limited by kinetic factors (associated with substrate temperature and deposition rate)), we describe a variety of other fabrication techniques by which such structures can indeed be fabricated with remarkable generality from preformed particles. Moreover, with organics, completely—rather than partially—embedded structures can be formed, if particles are spread on the surface of the polymer and the system is exposed to a suitable solvent vapour. This can be rationalized in terms of the above- mentioned inequality, provided that appropriate surface and/or interfacial tensions are calculated for this situation. Continuous subsurface films are predicted to become thermodynamically favourable during vacuum deposition, compared with embedded particulate structures, when particle coalescence becomes too slow to keep the projected-area coverage below certain maximum levels. This is expected as the particles exceed some minimum size, and we confirm this prediction experimentally. 相似文献
465.
Investigations of the in situ complex dielectric constant of sea ice were made using time-domain spectroscopy. It was found that (1) for sea ice with a preferred horizontal crystal c-axis alignment, the anisotropy or polarizing properties of the ice increased with depth, (2) brine inclusion conductivity increased with decreasing temperature down to about ?8°C, at which point the conductivity decreased with decreasing temperature, (3) the DC conductivity of sea ice increased with increasing brine volume, (4) the real part of the complex dielectric constant is strongly dependent upon brine volume but less dependent upon the brine inclusion orientation, (5) the imaginary part of the complex dielectric constant was strongly dependent upon brine inclusion orientation but much less dependent upon brine volume. Because the electromagnetic (EM) properties of sea ice are dependent upon the physical state of the ice, which is continually changing, it appears that only trends in the relationships between the EM properties of natural sea ice and its brine volume and brine inclusion microstructure can be established. 相似文献
466.
B Corenblum AM Sirek E Horvath K Kovacs C Ezrin 《Canadian Metallurgical Quarterly》1976,42(5):857-863
Six patients with acromegaly at examination were found to have pituitary adenomas composed of cells that secreted GH and PRL. This was demonstrated by the elevated serum hormone concentrations, by immunoperoxidase staining of 5 specimens, and by electron microscopic examination of 4. Ultrastructural characteristics, described in detail, suggest that these adenomas were mixed adenomas consisting of 2 well-defined, distinct cell types, each secreting one hormone. By immunoperoxidase staining some cells were found to contain immunoreactive growth hormone, other cells immunoreactive prolactin. No cells were detected exhibiting immunostaining for both growth hormone and prolactin. Eelctron microscopy, consistent with the results of immunostaining, revealed the presence of two distinct cell types, distinguishable from each other by their characteristic fine structural features. No intermediate forms were noted. Thus there was no evidence to suggest that one cell type might transform to the other. Present findings seem to indicate that mixed adenomas secreting growth hormone as well as prolactin and consisting of somatotrophs as well as lactotrophs do occur in the human pituitary gland. Although all the results obtained so far suggest that these tumors are composed of two distinct cell types and thus can be interpreted as representing real mixed adenomas, further work is required to establish whether or not they derive from one common progenitor. 相似文献
467.
Fox Ronald E.; Kovacs Arthur L.; Graham Stanley R. 《Canadian Metallurgical Quarterly》1985,40(9):1042
Presents 20 proposals designed comprehensively to overhaul the system by which professional psychologists are educated, trained, identified, licensed, and certified for specialty practice. Though many of the proposals are controversial and revolutionary (e.g., the appropriate professional degree is doctor of psychology [PsyD]), it is argued that it is only through such a comprehensive change that the profession will be able to achieve maturity as an independent discipline worthy of the support and the sanction of society. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
468.
469.
Federica Papaccio Daniela Kovacs Barbara Bellei Silvia Caputo Emilia Migliano Carlo Cota Mauro Picardo 《International journal of molecular sciences》2021,22(14)
Solid tumors are complex systems characterized by dynamic interactions between neoplastic cells, non-tumoral cells, and extracellular components. Among all the stromal cells that populate tumor microenvironment, fibroblasts are the most abundant elements and are critically involved in disease progression. Cancer-associated fibroblasts (CAFs) have pleiotropic functions in tumor growth and extracellular matrix remodeling implicated in local invasion and distant metastasis. CAFs additionally participate in the inflammatory response of the tumor site by releasing a variety of chemokines and cytokines. It is becoming clear that understanding the dynamic, mutual melanoma–fibroblast relationship would enable treatment options to be amplified. To better characterize melanoma-associated fibroblasts, here we analyzed low-passage primary CAFs derived from advanced-stage primary skin melanomas, focusing on the immuno-phenotype. Furthermore, we assessed the expression of several CAF markers and the production of growth factors. To deepen the study of CAF–melanoma cell crosstalk, we employed CAF-derived supernatants and trans-well co-culture systems to evaluate the influences of CAFs on (i) the motogenic ability of melanoma cells, (ii) the chemotherapy-induced cytotoxicity, and (iii) the release of mediators active in modulating tumor growth and spread. 相似文献
470.
Luca Marsili Jennifer Sharma Alberto J. Espay Alice Migazzi Elhusseini Abdelghany Emily J. Hill Kevin R. Duque Matthew C. Hagen Christopher D. Stephen Gabor G. Kovacs Anthony E. Lang Marios Hadjivassiliou Manuela Basso Marcelo A. Kauffman Andrea Sturchio 《International journal of molecular sciences》2021,22(14)
The gold standard for classification of neurodegenerative diseases is postmortem histopathology; however, the diagnostic odyssey of this case challenges such a clinicopathologic model. We evaluated a 60-year-old woman with a 7-year history of a progressive dystonia–ataxia syndrome with supranuclear gaze palsy, suspected to represent Niemann–Pick disease Type C. Postmortem evaluation unexpectedly demonstrated neurodegeneration with 4-repeat tau deposition in a distribution diagnostic of progressive supranuclear palsy (PSP). Whole-exome sequencing revealed a new heterozygous variant in TGM6, associated with spinocerebellar ataxia type 35 (SCA35). This novel TGM6 variant reduced transglutaminase activity in vitro, suggesting it was pathogenic. This case could be interpreted as expanding: (1) the PSP phenotype to include a spinocerebellar variant; (2) SCA35 as a tau proteinopathy; or (3) TGM6 as a novel genetic variant underlying a SCA35 phenotype with PSP pathology. None of these interpretations seem adequate. We instead hypothesize that impairment in the crosslinking of tau by the TGM6-encoded transglutaminase enzyme may compromise tau functionally and structurally, leading to its aggregation in a pattern currently classified as PSP. The lessons from this case study encourage a reassessment of our clinicopathology-based nosology. 相似文献