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排序方式: 共有861条查询结果,搜索用时 15 毫秒
61.
Sciarretta S Ferrucci A Ciavarella GM De Paolis P Venturelli V Tocci G De Biase L Rubattu S Volpe M 《American journal of hypertension》2007,20(7):784-791
BACKGROUND: Previous studies have shown that metabolic syndrome (MS) is associated with an increased susceptibility to develop cardiovascular damage (CD). Experimental evidence indicates that inflammation and fibrosis could play a critical role in the development of CD in hypertension. This issue has not been clarified yet in patients with MS. The aim of our study was to investigate the relationship between markers of inflammation and fibrosis with CD in hypertensive patients with and without MS. METHODS: One hundred twenty-eight essential hypertensive patients were included in the study: 51 with MS and 77 without MS. Clinical, biochemical parameters, 24-h urinary albumin excretion rate (UAER), levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), and procollagen type 1 carboxy-terminal propeptide (PICP) were measured. All patients underwent an echocardiographic examination with transmitral Doppler and tissue Doppler imaging (TDI). RESULTS: Left ventricular mass indexed by height(2.7) (LVM/h(2.7)) (P < .001), early diastolic peak flow velocity/early myocardial diastolic velocity ratio (E/Em ratio), a TDI index of diastolic function (P < .001), and 24-h UAER (P < .05) were significantly higher in the group with MS, whereas peak myocardial systolic velocity (Sm), a TDI index of systolic function (P < .001), was lower. Serum levels of CRP (P < .001), TNF-alpha (P < .05), TGF-beta (P < .01), and PICP (P < .001) were significantly increased in MS. These markers were significantly related to higher LVMI(2.7), higher E/Em ratio, and increased 24-h UAER and a lower Sm in the whole population, with a further significant enhancement in MS. CONCLUSIONS: Cardiovascular damage is more frequent in hypertensives with MS than in hypertensives without MS, and this is significantly related to the increased levels of inflammation and fibrosis found in hypertensives with MS. 相似文献
62.
Nasuti C Gabbianelli R Falcioni ML Di Stefano A Sozio P Cantalamessa F 《Toxicology》2007,229(3):194-205
Pyrethroids are a class of insecticides involved in different neurological disorders. They cross the blood-brain barrier and exert their effect on dopaminergic system, contributing to the burden of oxidative stress in Parkinson's disease through several pathways. The aim of the present study was to evaluate the effect of neonatal exposition to permethrin and cypermethrin (1/10 of DL(50)) in rats from the eighth to the fifteenth day of life. Open-field studies showed increased spontaneous locomotor activity in the groups treated with permethrin and the one treated with cypermethrin, while a higher number of center entries and time spent in the center was observed for the cypermethrin-treated group. Lower dopamine and higher homovanillic acid levels were measured in the striatum from both treated groups. A reduction of blood glutathione peroxidase content was measured, while no change in blood superoxide dismutase was observed. Carbonyl group formation increased in striatum, but not in erythrocytes. Lipid peroxidation occurred in erythrocytes, but not in striatum. No changes in fluidity at different depths of plasma membrane were measured in striatum or erythrocytes. The activation of monocyte NADPH oxidase by phorbol esters (PMA) shows that superoxide anion production was reduced in the pyrethroid-treated groups compared to the control group. Our studies suggest that neonatal exposition to permethrin or cypermethrin induces long-lasting effects after developmental exposure giving changes in open-field behaviors, striatal monoamine level, and increased oxidative stress. Although the action of pyrethroids on various target cells is different, a preferential interaction with the extracellular side of plasma membrane proteins can be observed. 相似文献
63.
Scala Daniela Mucherino Sara Wirth Francesca Orlando Valentina Polidori Piera Faggiano Maria Ernestina Iovine Daniela Saturnino Paola Cattel Francesco Costantini Alberto Giua Corrado Makoul Gregory Azzopardi Lilian M. Menditto Enrica 《International journal of clinical pharmacy》2022,44(4):1037-1045
International Journal of Clinical Pharmacy - Effective communication strategies in health care help to enhance patient empowerment and improve clinical outcomes. Adapt the original Communication... 相似文献
64.
65.
Takemoto SK Arns W Bunnapradist S Garrison LP Guirado L Kalo Z Oniscu G Opelz G Scolari MP Stefoni S Yaqoob M Brennan DC 《Transplantation》2008,86(1):18-25
Transplantation offers a unique opportunity to demonstrate the complementary roles of randomized controlled trials and outcome research. The surgery and collaboration necessary for the transplant procedure makes randomization and blinding difficult. Because essentially every recipient is included in a transplant registry, sampling bias is minimized. Regulatory agencies generally do not consider outcomes research when assessing efficacy of new drugs or medical interventions. This workgroup summary examines the suitability of outcomes research to complement results of randomized controlled trials and related issues: efficacy versus effectiveness, internal versus external validity, data types, limitations, and analysis methodologies. Many advances in outcomes research have been pioneered in transplantation. A case is made for regulatory and reimbursement authorities to use outcomes research when making efficacy, effectiveness, and coverage decisions in transplantation. 相似文献
66.
Tocci SL Madom IA Bradley MP Langer PR DiGiovanni CW 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2007,28(2):166-168
BACKGROUND: MRI is being used with increasing frequency and seems to have become more popular as a screening tool rather than as an adjunct to narrow specific diagnoses or plan operative interventions. Our hypothesis was that the rising accessibility of this test may be resulting in its overuse. METHODS: We retrospectively reviewed 221 consecutive patients referred over a 3-month period for treatment of a lower extremity problem to determine: (1) the number of patients who presented with an MRI already obtained from an outside source, (2) the number of patients who obtained an MRI from the foot and ankle specialist after referral, and (3) the number of times the foot and ankle specialist used these studies or found them helpful in the care of the patient. Fractures (20) were excluded. RESULTS: Of the 201 patients without fractures included in the study, 19.9% (40 of 201) had MRI scans during the course of their treatment; 15.4% (31 of 201) presented to their initial visit with an MRI scan from an outside source, and 4.5% (9 of 201) received MRI scans as ordered by the foot and ankle specialist. Eighty-seven percent (27 of 31) of the pre-referral MRI scans were thought to be unnecessary, and 48.4% (15 of 31) had radiographic interpretations that were considered either immaterial to the patient's pertinent clinical diagnosis or inconsistent with the specialist's interpretations. All nine MRI scans ordered by the specialist were useful in the care of the patient. Therefore, of the 221 consecutive patients, the foot and ankle specialist would have ordered MRI scans in only 5.9% (13 of 221). CONCLUSIONS: This study suggests that many of the pre-referral foot or ankle MRI scans obtained before evaluation by a foot and ankle specialist are not necessary. Further studies need to be performed to determine the role of MRI in the screening of foot and ankle disorders. 相似文献
67.
Andrea Ferrari Michela Casanova Filippo Spreafico Roberto Luksch Monica Terenziani Graziella Cefalo Maura Massimino Lorenza Gandola Piera Navarria Franca Fossati-Bellani 《Pediatric hematology and oncology》1999,16(5):415-421
A retrospective observational study was performed on a series of 12 consecutive pediatric patients treated over a 20-year period at the Istituto Nazionale Tumori, Milano. Conservative surgery was the treatment of choice in all patients; radical excision was obtained at diagnosis in 9 cases and after primary chemotherapy in 1 case. Five patients were subjected to surgery alone, and one to postoperative radiotherapy. After a median follow-up of 11 years (range 1-20), all the patients were alive without evidence of disease, 11 in first complete remisson, and 1 after local relapse. In agreement with other reports, the authors underline the unquestionable pivotal role of radical surgery in the treatment of liposarcoma. The high proportion of resectable tumors accounts for the excellent survival of the patients in this study. The role of both adjuvant chemotherapy and radiotherapy is uncertain and awaits multicentric cooperative prospective studies. 相似文献
68.
69.
Raha D Nehar S Paswan B Rebuffat P Neri G Naskar R Kumari K Raza B Rao NV Macchi C Sen NS Nussdorfer GG Ahmad MF 《International journal of molecular medicine》2007,20(1):91-95
Insulin-like growth factor (IGF)-I is a ubiquitously synthesized peptide that, along with IGF-II, acts via the IGF-R type I receptor. IGF-I and its receptor are expressed in the adrenal gland of humans and bovines, the secretion of which they seem to stimulate. As in humans and cows, the main glucocorticoid hormone secreted by guinea-pig adrenals is cortisol, and hence we have studied the adrenocortical effects of IGF-I in this species. In vivo experiments showed that prolonged IGF-I administration raised the plasma concentration of cortisol in both normal and dexamethasone/captopril-treated guinea pigs, thereby ruling out the possibility that IGF-I may act by activating the hypothalamic-pituitary-adrenal axis and the renin-angiotensin system. In vitro experiments demonstrated that IGF-I enhanced basal, but not maximally agonist [ACTH and angiotensin-II (Ang-II)]-stimulated, cortisol secretion from freshly dispersed guinea-pig inner adrenocortical cells. The IGF-I immuno-neutralization suppressed the IGF-I secretagogue effect, without altering the cortisol response to both ACTH and Ang-II. IGF-I raised cyclic-AMP and inositol triphosphate release from dispersed guinea-pig cells, and the effect was reversed by the adenylate cyclase inhibitor SQ-22536 and the phospholipase-C (PLC) inhibitor U-73122. SQ-22536, U-73122, the protein kinase (PK) A inhibitor H-89 and the PKC inhibitor calphostin-C decreased by approximately 50% the cortisol response of dispersed cells to IGF-I, and the combined exposure to SQ-22536 and U-73122 abolished it. We conclude that IGF-I stimulates glucocorticoid secretion from guinea-pig adrenocortical cells, acting via selective receptors coupled to both the adenylate cyclase/PKA- and PLC/PKC-dependent signaling cascades. 相似文献
70.
Luccardini C Yakovlev A Gaillard S van 't Hoff M Alberola AP Mallet JM Parak WJ Feltz A Oheim M 《Journal of biomedicine & biotechnology》2007,2007(7):68963
Semiconductor nanocrystals (NCs) are increasingly being used as photoluminescen markers in biological imaging. Their brightness, large Stokes shift, and high photostability compared to organic fluorophores permit the exploration of biological phenomena at the single-molecule scale with superior temporal resolution and spatial precision. NCs have predominantly been used as extracellular markers for tagging and tracking membrane proteins. Successful internalization and intracellular labelling with NCs have been demonstrated for both fixed immunolabelled and live cells. However, the precise localization and subcellular compartment labelled are less clear. Generally, live cell studies are limited by the requirement of fairly invasive protocols for loading NCs and the relatively large size of NCs compared to the cellular machinery, along with the subsequent sequestration of NCs in endosomal/lysosomal compartments. For long-period observation the potential cytotoxicity of cytoplasmically loaded NCs must be evaluated. This review focuses on the challenges of intracellular uses of NCs. 相似文献