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排序方式: 共有663条查询结果,搜索用时 15 毫秒
71.
Granger CV Deutsch A Russell C Black T Ottenbacher KJ 《American journal of physical medicine & rehabilitation / Association of Academic Physiatrists》2007,86(11):883-892
OBJECTIVES: To describe the modifications made to the FIM instrument when it was incorporated into the Inpatient Rehabilitation Facility-Patient Assessment Instrument (IRF-PAI), and to compare FIM data collected before and after the IRF prospective payment system (IRF-PPS) was implemented in 2002 for patients with stroke. DESIGN: Year-by-year comparison of data of Medicare patients with stroke discharged in 1998-2003 from 411 IRFs that submitted data to the Uniform Data System for Medical Rehabilitation for each of those years. RESULTS: In the pre-PPS period, admission motor FIM ratings decreased slightly, and discharge motor, admission cognitive, and discharge cognitive ratings remained stable. Between 2001 and 2003, all four ratings decreased: admission motor by 1.8 FIM units, discharge motor by 3.3 FIM units, and admission and discharge cognitive each by 1.0 FIM unit. The lower admission FIM ratings led to an increase in the mean case-mix index from 1.39 to 1.49. CONCLUSIONS: The decrease in FIM ratings in the IRF-PAI/PPS years may reflect alterations in coding practices as a result of changed rules for rating the FIM instrument, "downcoding" leading to assignment into higher-paying categories, changes in the IRF patient population, and/or changes in IRF patient outcomes. Coding changes should be considered when comparing pre-PPS and PPS FIM data. 相似文献
72.
Human macrophage maturation and heterogeneity: analysis with a newly generated set of monoclonal antibodies to differentiation antigens 总被引:4,自引:0,他引:4
We have analyzed the expression of late differentiation antigens during terminal in vitro maturation of human macrophages (M phi) from blood monocytes (MO) in comparison to their distribution among mature M phi residing in various tissue sites. By immunizing mice with M phi derived from blood MO by culture on hydrophobic Teflon foils, monoclonal antibodies (mAbs) were developed (MAX.1, MAX.2, MAX.3, MAX.11) that reacted with lineage-restricted differentiation antigens. These antigens were expressed exclusively on M phi or were markedly increased after in vitro differentiation. The only overlap to another hemopoietic cell lineage was observed with MAX.3, which is shared by platelets and megakaryocytes. In the course of M phi maturation in vitro, the MAX.1 and MAX.3 antigens are detected within the cytoplasm two days before they appear on the cell surface. In contrast, the MAX.11 antigen is expressed simultaneously in the cytoplasm and at the cell surface, is found in varying degrees on a minor portion of blood MO and U937 cells, and is expressed rapidly at high density during early M phi differentiation in vitro. Among conventional mAbs that do not react with MO we found those against the transferrin (TF)-receptor, the BA-2, and the PCA1 antigen to label M phi. M phi matured in vivo and isolated from body fluids were positive with some but not all MAX mAbs. Distinctive patterns were observed with pulmonary M phi, exudate M phi from pleural and peritoneal effusions, synovial fluids, and early lactation milk. M phi from the alveolar space, for example, constantly expressed the MAX.2 antigen but not the MAX.3 antigen. Pleural effusion M phi, however, did not react with the MAX.1 mAb, but in most cases, it did react with the MAX.3 mAb. The detection of novel differentiation antigens, all expressed on monocyte-derived M phi but differently expressed on site-specific M phi in situ, underlines the remarkable heterogeneity among human M phi. The expression of these antigens is flexible because those MAX antigens that were not expressed in situ could be induced if cells from distinct tissue sites were cultured in vitro for several days. MAX mAbs may be of potential value to study both the sequential stages of maturation within the M phi lineage as well as differential developments induced by various culture conditions in parallel to environmental factors in vivo. 相似文献
73.
Ca2+ and phospholipid-dependent protein kinase (protein kinase C) activity is not necessarily required for secretion by human neutrophils 总被引:2,自引:0,他引:2
Ca2+-dependent and phospholipid-dependent protein kinase (PKC) is a receptor for and is activated by phorbol esters. This enzyme is reportedly involved in the mechanism of superoxide anion (O2-) production and the release of intracellular granule contents from human neutrophils. As previously reported by others, we found that greater than 75% of the total cellular PKC activity existed in a soluble form in untreated neutrophils and that this activity was enhanced in a dose- dependent manner by phorbol 12-myristate 13-acetate (PMA) and by phorbol 12,13-dibutyrate (PDBu). Furthermore, mezerein, an analogue of PMA that is thought to be a competitive inhibitor, did not activate PKC, and on the contrary, inhibited PMA-stimulated activity in a dose- dependent manner. Pretreatment of intact neutrophils with PMA or PDBu caused the "translocation" of PKC activity to the insoluble cell fraction; PKC translocation was not detected after mezerein stimulation at any of the tested concentrations. Neither did mezerein cause an increase in intracellular Ca2+, as monitored by Quin 2 fluorescence. Both phorbol esters and mezerein stimulated intact neutrophils to generate O2- and release lysosomal enzymes into the extracellular medium. Finally sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated key differences in the patterns of endogenous phosphoproteins of neutrophils stimulated with phorbol as compared with mezerein. We therefore suggest that PKC activation may not be the only pathway required to elicit neutrophil responses. 相似文献
74.
以动脉粥样硬化为基础的心血管疾病是人类健康面临的严重挑战.人们对动脉粥样硬化发生、发展进行漫长和不懈的探索.至今,其机制与过程仍不十分清楚. 相似文献
75.
Peek MK Patel KV Ottenbacher KJ 《The journals of gerontology. Series A, Biological sciences and medical sciences》2005,60(3):334-339
BACKGROUND: Very few studies have examined how disability develops among older Mexican Americans. To determine how disability develops, we explored the Disablement Process model, which posits that impairment, measured by muscle strength, leads to functional limitations, which lead to disability, which ultimately is associated with health-related quality of life (HRQOL). METHODS: A structural equation model approach was used (AMOS 4) with data collected on 622 Mexican Americans aged 71 or older residing in the Southwest. RESULTS: Our results show preliminary support for the Disablement Process model. Impairment is significantly associated with functional limitation (beta =.36, z value = 7.2), which is significantly associated with disability (beta = -.53, z value = 16.1). Finally, disability is significantly related to both physical and mental components of HRQOL (beta = -.69, z value = 23.4; beta = -.26, z value = 6.5, respectively). CONCLUSIONS: Muscle strength as a measure of impairment and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) score as a measure of HRQOL are important factors in understanding disability in older Mexican Americans. 相似文献
76.
Amany H Ahmed KJ Shankar Hossein Eftekhari MS Munir Jillian Robertson Alan Brewer Igor V Stupin S Ward Casscells 《Experimental & Clinical Cardiology》2007,12(4):189-196
Silent myocardial ischemia (SMI) is increasingly being recognized as part of the spectrum of ischemic heart disease. The spectrum of SMI ranges from asymptomatic coronary artery disease to critical illness necessitating intensive care. Although many diagnostic tools have been used to identify low- and high-risk subgroups, their use is limited by modest sensitivities and specificities. The present review identifies current concepts in the management of SMI in various clinical settings, as well as emerging technologies that may simplify the diagnosis and treatment of this condition. 相似文献
77.
Neutrophil elastase produces 52-kD and 30-kD glucocorticoid receptor fragments in the cytosol of human leukemia cells 总被引:1,自引:0,他引:1
Characterization of glucocorticoid receptors in leukemia cells is important to understand mechanisms of glucocorticoid resistance but has been impeded by receptor fragmentation in cytosol extracts. We recently found that formation of 52- and 30-kilodalton (kD) glucocorticoid receptor fragments in cytosol of leukemia cells is due to proteolysis and is blocked by diisopropylfluorophosphate (DFP). In the present study, we identify a 28-kD serine protease in cytosol of leukemia cells that binds [3H]DFP and correlates with the formation of 52- and 30-kD receptor fragments. This protease is immunoprecipitated by antiserum to neutrophil elastase. Limited digestion of [3H]dexamethasone-21-mesylate- labeled receptors by purified neutrophil elastase produces 52- and 30- kD receptor fragments. Receptor fragmentation in the cytosol of leukemia cells in inhibited by methoxysuccinyl-alanyl-alanyl-prolyl- valyl-chloromethylketone, a highly specific inhibitor of neutrophil elastase. The addition of as few as 5% neutrophils to a lymphoid cell suspension provides sufficient elastase to produce receptor fragmentation. Our findings indicate that neutrophil elastase is responsible for receptor fragmentation in the cytosol of leukemia cells. The neutrophil elastase may be endogenous to the leukemia cells or may come from neutrophils that contaminate leukemia cell suspensions. 相似文献
78.
Deficiency of intact thrombospondin and membrane glycoprotein Ia in platelets with defective collagen-induced aggregation and spontaneous loss of disorder 总被引:11,自引:7,他引:11
Kehrel B; Balleisen L; Kokott R; Mesters R; Stenzinger W; Clemetson KJ; van de Loo J 《Blood》1988,71(4):1074-1078
Platelets from a patient with a severe lifelong bleeding tendency, which later spontaneously disappeared, lacked intact thrombospondin and glycoprotein (GP) Ia. Before disappearance of the bleeding disorder, results of coagulation studies and platelet aggregation in response to adenosine diphosphate (ADP), arachidonic acid, thrombin, A23187, epinephrine, and ristocetin were normal. In contrast, aggregation only occurred in the presence of collagen or wheat germ agglutinin at unusually high doses of these agonists. The platelets adhered normally to purified bovine and human type I collagen, and they did not spread in the presence of methylated type I collagen. No collagen-induced clot retraction was observed. Two-dimensional gel electrophoretic analyses of platelet proteins and immunologic studies showed that intact thrombospondin and GP Ia were absent. Aggregation in response to collagen could be restored by adding thrombospondin. Disappearance of the bleeding tendency occurred at the onset of menopause; subsequent analyses revealed that thrombospondin and GP Ia were present in platelets and that collagen-induced platelet aggregation was normal. These results suggest that both thrombospondin and GP Ia are essential in collagen-induced platelet aggregation. The spontaneous disappearance of the bleeding tendency may have been related to hormonal influences. 相似文献
79.
Schmidt GM; Bross KJ; Blume KG; Enders N; Santos S; Novitski M; Chillar RK 《Blood》1980,55(2):299-303
An immunohistochemical procedure for the detection of immunoglobulin G adherent to platelets is described. The peroxidase anti-peroxidase method is used to detect antibody activity directed against platelets from normal donors in the sera from 305 individuals. These subjects were divided into three groups: group 1, patients referred for tissue typing; group 2, healthy normal females; group 3, healthy normal males. In group 1, 28% of the sera were found to be positive; in most of these a history of prior transfusions was obtained. In group 2, 7.4% were found to be positive, most having previous pregnancies. Only 1% were found to be positive in group 3, and no reason for presensitization was found. Results from the indirect immunofluorescence technique served as a control and as a means to compare the sensitivity. Under the conditions chosen, the peroxidase anti-peroxidase test was two to eight times more sensitive than the immunofluorescence technique. Specificity of the peroxidase anti-peroxidase technique was demonstrated using a monospecific anti-PLA1 antiserum. It is concluded that the peroxidase anti-peroxidase slide technique may be a useful tool in the study of platelet-related immunophenomena. 相似文献
80.
GF Nash KJ Turner T Hickish J Smith M Chand BJ Moran 《Annals of the Royal College of Surgeons of England》2012,94(7):456-462
Adenocarcinoma of the prostate and rectum are common male pelvic cancers and may present synchronously or metachronously and, due to their anatomic proximity. The treatment of rectal or prostate cancer (in particular surgery and/or radiotherapy) may alter the presentation, incidence and management should a metachronous tumour develop. This review focuses on the interaction between prostatic and rectal cancer diagnosis and management. We have restricted the scope of this large topic to general considerations, management of rectal cancer after prostate cancer treatment and vice versa, management of synchronous disease and cancer follow-up issues. 相似文献