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981.
Retinal pigment epithelial cells secrete urokinase-type plasminogen activator and its inhibitor PAI-1. 总被引:3,自引:0,他引:3
V Sirén R W Stephens E M Salonen A Vaheri P Summanen I Immonen 《Ophthalmic research》1992,24(4):203-212
Secretion of plasminogen activators and their inhibitors was examined in cultures of human retinal pigment epithelial (RPE) cells. The methods employed were zymography and reverse zymography, solid-phase immunocapture assay, metabolic labeling followed by immunoprecipitation, and immunofluorescence. The results showed that these cells produce urokinase-type plasminogen activator (u-PA) and a plasminogen activator inhibitor (PAI) which is immunologically and biochemically similar to PAI-1. Tissue-type plasminogen activator activity (t-PA) was not detected, but we detected small amounts of t-PA in an inactive complex with inhibitor in RPE cell-conditioned media. We conclude that RPE cells have the potential to utilize u-PA-catalyzed plasminogen activation which is subject to regulation by PAI-1. These results may have a bearing on the pathogenesis of proliferative retinal diseases. 相似文献
982.
Robert M. Palmer Steven R. Counsell Seth C. Landefeld 《Disease Management & Health Outcomes》2003,11(8):507-517
Older patients often experience a loss of independent physical functioning during the course of an acute illness that requires hospitalization. Although functional outcomes are not usually the focus of care in the hospital, they may be critical determinants of the quality of life, physical independence, cost of care, and prognosis among older patients.Based on a conceptual model of the dysfunctional syndrome (functional decline associated with hospitalization) we developed, implemented and evaluated a multi-component intervention termed Acute Care for Elders (ACE), in hospital medical units of two urban hospitals. ACE is a model of care that combines the principles of geriatric assessment and quality improvement. The ACE intervention includes a prepared environment (environmental modification), patient-centered care (interdisciplinary assessment), interdisciplinary team rounds and planning for home, and medical care review. Results of randomized clinical trials support the effectiveness of ACE to improve outcomes of hospitalization for older patients. Improved functional status, lower risk of nursing home placement and higher levels of patient and professional satisfaction with care are achievable with ACE.The challenges of establishing an ACE unit in community hospitals can be met through a systematic process of implementation and evaluation.ACE is a multi-component intervention that is potentially transportable to other hospital units, with benefits for patients, health professionals and hospital administrators. 相似文献
983.
984.
985.
Marc Philippon Mara Schenker Karen Briggs David Kuppersmith 《Knee surgery, sports traumatology, arthroscopy》2007,15(7):908-914
Femoroacetabular impingement (FAI) occurs when an osseous abnormality of the proximal femur (cam) or acetabulum (pincer) triggers
damage to the acetabular labrum and articular cartilage in the hip. Although the precise etiology of FAI is not well understood,
both types of FAI are common in athletes presenting with hip pain, loss of range-of-motion, and disability in athletics. An
open surgical approach to decompressing FAI has shown good clinical outcomes; however, this highly invasive approach inherently
may delay or preclude a high level athlete’s return to play. The purpose of this study was to define associated pathologies
and determine if an arthroscopic approach to treating FAI can allow professional athletes to return to high-level sport. Hip
arthroscopy for the treatment of FAI allows professional athletes to return to professional sport. Between October 2000 and
September 2005, 45 professional athletes underwent hip arthroscopy for the decompression of FAI. Operative and return-to-play
data were obtained from patient records. Average time to follow-up was 1.6 years (range: 6 months to 5.5 years). Forty two
(93%) athletes returned to professional competition following arthroscopic decompression of FAI. Three athletes did not return
to play; however, all had diffuse osteoarthritis at the time of arthroscopy. Thirty-five athletes (78%) remain active in professional
sport at an average follow-up of 1.6 years. Arthroscopic treatment of FAI allows professional athletes to return to professional
sport. 相似文献
986.
987.
R. Alcázar-Olán D. Reyes-Chiquete R. Plancarte-Sánchez 《Clinical & translational oncology》2003,5(2):65-69
Resumen El equipo médico debe estar preparado para evaluar a los pacientes que solicitan muerte asistida.
En esta revisión hemos recopilado de la literatura internacional los criterios médicos y psicológicos para evaluar a los pacientes
que solicitan muerte asistida con la finalidad de aliviar las necesidades fisicas, psicológicas y sociales de los pacientes
y sus familias.
Se realizó un estudio de tipo exploratorio seleccionando los artículos que propusieran protocolos de valoración psicológica
y médica de los pacientes que solicitan muerte asistida. Se analizó qué aspectos son los que se evalúan con mayor frecuencia
en la literatura internacional.
Se identificaron dos posturas generales para la valoración del paciente: por un lado la valoración de su competencia para
la toma de decisiones y por otro la valoración del sufrimiento físico, seguido por el sufrimiento psicológico, social, existencial/espiritual,
la relación médico-paciente y la relación médico-familiares. Finalmente se enumeran una serie de principios que pueden guiar
al clínico ante la petición de muerte asistida.
相似文献
988.
989.
A Martins H Cortez-Pinto P Marques-Vidal N Mendes S Silva N Fatela H Glória R Marinho I Távora F Ramalho M Carneiro de Moura 《Liver international》2006,26(6):680-687
INTRODUCTION: Hepatocellular carcinoma is a leading cause of death from cancer worldwide. Survival of patients depends on tumor extension and liver function, but yet there is no consensual prognostic model. AIMS: To evaluate the influence on survival of pretreatment parameters (clinico-laboratorial, liver function, tumor extension, Okuda and Cancer of the Liver Italian program (CLIP) staging) and treatment modalities. METHODS: We retrospectively analyzed 207 patients, diagnosed between 1993 and 2003. The initial treatment was: surgery--six patients; radiofrequency ablation--21; percutaneous ethanol injection--29; transarterial chemoembolization--49; tamoxifen--49; supportive care alone--53. Factors determining survival were assessed by Kaplan-Meier method and Cox regression models. RESULTS: Median survival was 24 months. In univariate analysis, Child-Pugh classification and Model for end-stage liver disease (MELD) score, portal vein thrombosis (PVT), tumor size, number of lesions, Okuda and CLIP scores were all associated with prognosis (P < 0.001). Alpha-fetoprotein levels were not predictive of survival. Independent predictors of survival were ascites, bilirubin, PVT and therapeutic modalities (P < 0.001). In early stage hepatocellular carcinoma (HCC), survival was similar for both percutaneous ablation modalities, either radiofrequency or ethanol injection (P = NS). In advanced HCC, survival was better in patients receiving tamoxifen than supportive care alone (P < 0.001). CONCLUSION: This study reinforces the importance of baseline liver function (Child-Pugh classification and MELD score) in the survival of patients with HCC, although staging systems allowed the stratification of patients in different prognostic groups. Ascites, bilirubin and PVT were independent pretreatment predictors of survival. All treatments influenced the patient's outcome, whether in early or advanced stages. 相似文献
990.
Bego?a López Arantxa González Ramón Querejeta Mariano Larman Javier Díez 《Journal of the American College of Cardiology》2006,48(1):89-96
OBJECTIVES: We sought to assess the distribution of collagen deposits and collagen degradation in hypertensive patients with either systolic heart failure (SHF) or diastolic heart failure (DHF). BACKGROUND: Increased collagen synthesis and deposition have been described in the myocardium of heart failure (HF) hypertensive patients. METHODS: We studied 39 HF hypertensive patients subdivided into two groups: 16 with SHF and 23 with DHF. Endomyocardial biopsies were performed to quantify mysial (i.e., perimysial plus endomysial) and perivascular and scar-related collagen volume fraction (CVF). Matrix metalloproteinase (MMP)-1 and its tissue inhibitor matrix metalloproteinase (TIMP)-1 were analyzed in cardiac samples by Western blot and immunohistochemistry, and in blood samples by enzyme-linked immunosorbent assay. RESULTS: Mysial CVF was lower in SHF hypertensive patients than in normotensive (p < 0.05) and DHF hypertensive patients (p < 0.01). Perivascular and scar-related CVF was higher (p < 0.05) in the two groups of hypertensive patients than in normotensive subjects, and in SHF hypertensive compared with DHF hypertensive patients. The MMP-1:TIMP-1 ratio was increased (p < 0.05) in tissue and serum samples from the SHF hypertensive group compared with the other two groups of subjects. The MMP-1 expression was increased (p < 0.01) in the interstitium and cardiomyocytes of SHF hypertensive patients compared with DHF hypertensive and normotensive subjects. The serum MMP-1:TIMP-1 ratio was inversely correlated with ejection fraction (r = -0.510, p < 0.001) and directly correlated with left ventricular end-diastolic diameter (r = 0.549, p < 0.001) in all subjects. CONCLUSIONS: These findings show that the pattern of collagen deposits and the balance of the MMP-1/TIMP-1 system are different in the myocardium of SHF and DHF hypertensive patients. It is proposed that excessive degradation of mysial collagen may be related to the compromise of systolic function in HF hypertensive patients. 相似文献