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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   
53.
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   
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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   
56.
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   
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We recently demonstrated that lactoferrin, an antimicrobial glycoprotein, can inhibit adenovirus infection by competing for common glycosaminoglycan receptors. This study further characterizes the antiadenovirus activity of the protein, thus demonstrating that lactoferrin neutralizes infection by binding to adenovirus particles and that its targets are viral III and IIIa structural polypeptides.  相似文献   
59.
The angiotensin-converting enzyme (ACE) gene has been implicated in the manifestation of the phenotype of malignant hypertension (MH). In 1990 the ACE gene polymorphism characterized by the insertion or deletion of a 287-base pair fragment in the 17q23 chromosome was identified. The DD genotype is associated with increased tissue and circulating ACE levels and elevated angiotensin II. ACE polymorphism was studied in 48 patients with MH, 25 patients with non-MH, and a control group of 78 normotensive individuals by real-time polymerase chain reaction using the LightCycler system (Roche Diagnostics Corporation, Indianapolis, IN). The DD genotype was found statistically more frequently in MH patients than controls (p=0.028; odds ratio, 2.5; confidence interval, 1.1-5.5). Presence of the DD genotype of the ACE gene is more frequent in MH patients than in controls, indicating that this genotype could be a significant risk factor and a predictor for the development of MH.  相似文献   
60.
Though most follicular lymphoma biomarkers rely on tumor features, the host genetic background may also be relevant for outcome. Here we aimed at verifying the contribution of candidate polymorphisms of FCγ receptor, DNA repair and detoxification genes to prognostic stratification of follicular lymphoma treated with immunochemotherapy. The study was based on 428 patients enrolled in the FOLL05 prospective trial that compared three standard-of-care regimens (rituximab-cyclophosphamide-vincristine-prednisone versus rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone versus rituximab-fludarabine-mitoxantrone) for the first line therapy of advanced follicular lymphoma. Polymorphisms were genotyped on peripheral blood DNA samples. The primary endpoint was time to treatment failure. Polymorphisms of FCGR2A and FCGR3A, which have been suggested to influence the activity of rituximab as a single agent, did not affect time to treatment failure in the pooled analysis of the three FOLL05 treatment arms that combined rituximab with chemotherapy (P=0.742, P=0.252, respectively). These results were consistent even when the analysis was conducted by intention to treat, indicating that different chemotherapy regimens and loads did not interact differentially with the FCGR2A and FCGR3A genotypes. The genotype of MLH1, which regulates the genotoxic effect of doxorubicin, significantly affected time to treatment failure in patients in the rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone arm (P=0.001; q<0.1), but not in arms in which patients did not receive doxorubicin (i.e., the rituximab-cyclophosphamide-vincristine-prednisone and rituximab-fludarabine-mitoxantrone arms). The impact of MLH1 on time to treatment failure was independent after adjusting for the Follicular Lymphoma International Prognostic Index and other potential confounding variables by multivariate analysis. These data indicate that MLH1 genotype is a predictor of failure to benefit from rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone treatment in advanced follicular lymphoma and confirm that FCGR2A and FCGR3A polymorphisms have no impact when follicular lymphoma is treated with rituximab plus chemotherapy (clinicaltrials.gov identifier: NCT00774826).  相似文献   
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