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51.
Prostaglandins are important mediators of bone repair, and cyclooxygenases are required for prostaglandin production. Data from animal studies suggest that both non-specific and specific inhibitors of cyclooxygenases impair fracture healing but that this is due to the inhibition of COX-2 and not COX-1. Although these data raise concerns about the use of COX-2-specific inhibitors as anti-inflammatory or anti-analgesic drugs in patients undergoing bone repair, clinical reports have been inconclusive. Because animal data suggest that the effects of COX-2 inhibitors are both dose-dependent and reversible, in the absence of scientifically sound clinical evidence it is suggested that physicians consider short-term administration or other drugs in the management of these patients.  相似文献   
52.

Background

The child protection community is increasingly focused on developing tools to assess threats to child protection and the basic security needs and rights of children and families living in adverse circumstances. Although tremendous advances have been made to improve measurement of individual child health status or household functioning for use in low-resource settings, little attention has been paid to a more diverse array of settings in which many children in adversity spend time and how context contributes to threats to child protection. The SAFE model posits that insecurity in any of the following fundamental domains threatens security in the others: Safety/freedom from harm; Access to basic physiological needs and healthcare; Family and connection to others; Education and economic security. Site-level tools are needed in order to monitor the conditions that can dramatically undermine or support healthy child growth, development and emotional and behavioral health. From refugee camps and orphanages to schools and housing complexes, site-level threats exist that are not well captured by commonly used measures of child health and well-being or assessments of single households (e.g., SDQ, HOME).

Methods

The present study presents a methodology and the development of a scale for assessing site-level child protection threats in various settings of adversity. A modified Delphi panel process was enhanced with two stages of expert review in core content areas as well as review by experts in instrument development, and field pilot testing.

Results

Field testing in two diverse sites in India—a construction site and a railway station—revealed that the resulting SAFE instrument was sensitive to the differences between the sites from the standpoint of core child protection issues.  相似文献   
53.
The forebrain constitutes the most anterior part of the central nervous system, and is functionally crucial and structurally conserved in all vertebrates. It includes the dorsally positioned telencephalon and eyes, the ventrally positioned hypothalamus, and the more caudally located diencephalon [from rostral to caudal: the prethalamus, the zona limitans intrathalamica (ZLI), the thalamus and the pretectum]. Although antagonizing Wnt proteins are known to establish the identity of the telencephalon and eyes, it is unclear how various subdivisions are established within the diencephalon--a complex integration center and relay station of the vertebrate brain. The conserved forebrain-specific zinc-finger-containing protein Fezl plays a crucial role in regulating neuronal differentiation in the vertebrate forebrain. Here, we report a new and essential role of zebrafish Fezl in establishing regional subdivisions within the diencephalon. First, reduced activity of fezl results in a deficit of the prethalamus and a corresponding expansion of the ZLI. Second, Gal4-UAS-mediated fezl overexpression in late gastrula is capable of expanding the prethalamus telencephalon and hypothalamus at the expense of the ZLI and other fore- and/or mid-brain regions. Such altered brain regionalization is preceded by the early downregulation of wnt expression in the prospective diencephalon. Finally, fezl overexpression is able to restore the anterior forebrain and downregulate wnt expression in Headless- and/or Tcf3 (also known as Tcf7l1a)-deficient embryos. Our findings reveal that Fezl is crucial for establishing regional subdivisions within the diencephalon and may also play a role in the development of the telencephalon and hypothalamus.  相似文献   
54.
55.

Background  

High content screening (HCS)-based image analysis is becoming an important and widely used research tool. Capitalizing this technology, ample cellular information can be extracted from the high content cellular images. In this study, an automated, reliable and quantitative cellular image analysis system developed in house has been employed to quantify the toxic responses of human H4 neuroglioma cells exposed to metal oxide nanoparticles. This system has been proved to be an essential tool in our study.  相似文献   
56.
Interferons and the tumor cell   总被引:6,自引:0,他引:6  
Optimal use of interferons (IFNs) for the treatment of tumor disease requires experimental work in order to precisely define IFN actions. We have pointed out three modes of such actions relevant for the antitumor efficacy exerted by IFNs: effects on apoptosis, effects on genes involved in malignant transformation and effects on angiogenesis. These are but three selected areas forming a basis for the development of optimal IFN therapy. Further experimental work, undertaken in these and additional IFN areas, is mandatory for the most effective clinical use of IFNs for the treatment of tumor disease.Abbreviations IFN interferon - FGF basic fibroblast growth factor  相似文献   
57.
58.
Journal of Plant Growth Regulation - Exogenous application of abscisic acid (ABA) can cause fruit abscission. ABA indirectly reduces carbon assimilation via stomatal closure, but may also induce...  相似文献   
59.
IFN-alpha exerts prominent regulatory functions on the immune system. One such effect is the inhibition of proliferation of in vitro stimulated T lymphocytes. The exact physiological function of this activity is not known, but it has been implicated in the antiviral effects of IFN, its antitumor action in T-cell malignancies, and the regulation of the in vivo T-cell response. Here, we have investigated the mechanism underlying the IFN-alpha-mediated growth inhibition of normal human PHA- and IL-2-stimulated T lymphocytes by an analysis of how IFN-alpha treatment influences known molecular events that normally accompany the transition from quiescence to proliferation in these cells. IFN-alpha treatment was found to profoundly block S-phase entry of stimulated T lymphocytes. This correlated with a strong inhibition of IL-2-induced changes in G1-regulatory proteins, including the prevented up-regulation of G1 cyclins and cyclin-dependent kinases as well as an abrogation of mitogen-induced reduction of p27Kip1 levels. This latter effect was due to a maintained stability of the p27Kip1 protein in the IFN-alpha-treated cells. In line with these findings, phosphorylation of the pocket proteins was abrogated in IFN-alpha-treated cells. Furthermore, our data indicate that IFN-alpha has selective effects on the pathways that emerge from the IL-2 receptor because IFN-alpha treatment does not block IL-2-induced up-regulation of c-myc or Cdc25A.  相似文献   
60.
Osteogenic growth polypeptides regulate bone cell function in vitro and may act in vivo in an autocrine, paracrine, or endocrine manner. Several of these polypeptides are present in the blood in an inactive form. During postablation bone marrow regeneration these factors may be activated, released from the blood clot, and together with locally produced polypeptides mediate the initial intramedullary/systemic osteogenic phase of this process. Then, the same and/or other polypeptides expressed by stromal cells have the potential to promote the second phase of regeneration that consists of osteoclastogenesis, resorption of the transient intramedullary bone, and hemopoiesis. This may be an indirect influence since these polypeptides can regulate the stromal cell expression of some of the hemopoietic factors. Clinically, the osteogenic growth polypeptides that regulate osteogenesis and hemopoiesis have a potential role in osteoporosis therapy, implant bone surgery, and bone marrow transplantation. © 1994 Wiley-Liss, Inc.  相似文献   
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