978 research outputs found

    Head-to-head comparison between F-18-DOPA PET/CT and Ga-68-DOTA-peptide PET/CT in detecting intestinal neuroendocrine tumours:A systematic review and meta-analysis

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    Objective: The imaging of intestinal neuroendocrine tumours (NETs) relies on functional PET tracers; these tumours can be studied by means of both Ga-68-DOTA-peptides and F-18-DOPA PET/CT. As yet, it is unclear which of these two modalities offers the better sensitivity. We therefore conducted a meta-analysis to assess the available data. Design: PubMed, CENTRAL, Scopus and Web of Science were searched for studies comparing the sensitivity of Ga-68-DOTA-peptides and F-18-DOPA PET/CT; papers up to February 2021 were considered. Patients and Measurements: In each study, we considered sensitivity in terms of patient-based (PBA), region-based (RBA) and lesion-based analysis (LBA) and pooled the results yielded by each tracer. Multidisciplinary follow-up served as the standard of truth. Results: Of the 636 records identified, 6 articles published between 2008 and 2021 were finally selected, and 112 intestinal NET patients were included. The pooled sensitivity of F-18-DOPA PET/CT was 83%, 89% and 95% on PBA, RBA and LBA, respectively. Ga-68-DOTA peptide PET/CT showed sensitivity of 88%, 92% and 82% on PBA, RBA and LBA, respectively. No significant differences were found between the two tracers on PBA and RBA. By contrast, a clear trend towards significance in favour of F-18-DOPA PET/CT was identified on LBA. The presence of a significant difference in favour of F-18-DOPA PET/CT was confirmed in a subgroup analysis conducted only on the most recent and largest studies. In all three analyses, mild-to-high heterogeneity was found, while no publication bias was observed. Conclusion: Both F-18-DOPA PET/CT and Ga-68-DOTA-peptide PET/CT are reliable diagnostic procedures in patients with intestinal NETs. However, in terms of lesion detection, a non-negligible difference in favour of F-18-DOPA PET/CT was observed. Thus, the use of F-18-DOPA PET/CT could be considered as a first-line molecular procedure in intestinal NETs

    Search for CP Violation in the Decay Z -> b (b bar) g

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    About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, h^b=h^AbgVbh^VbgAb{\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab} and hb=h^Vb2+h^Ab2h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}, limits of \hat{h}_b < 0.59and and h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st

    Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions

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    Data taken with the ALEPH detector at LEP1 have been used to search for gamma gamma production of the glueball candidates f0(1500) and fJ(1710) via their decay to pi+pi-. No signal is observed and upper limits to the product of gamma gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) < 0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV at 95% confidence level.Comment: 10 pages, 3 figure

    Search for the standard model Higgs boson at LEP

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    Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV

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    A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81 GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the 95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure

    Chemical analysis of pottery demonstrates prehistoric origin for high-altitude alpine dairying

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    The European high Alps are internationally renowned for their dairy produce, which are of huge cultural and economic significance to the region. Although the recent history of alpine dairying has been well studied, virtually nothing is known regarding the origins of this practice. This is due to poor preservation of high altitude archaeological sites and the ephemeral nature of transhumance economic practices. Archaeologists have suggested that stone structures that appear around 3,000 years ago are associated with more intense seasonal occupation of the high Alps and perhaps the establishment of new economic strategies. Here, we report on organic residue analysis of small fragments of pottery sherds that are occasionally preserved both at these sites and earlier prehistoric rock-shelters. Based mainly on isotopic criteria, dairy lipids could only be identified on ceramics from the stone structures, which date to the Iron Age (ca. 3,000 - 2,500 BP), providing the earliest evidence of this practice in the high Alps. Dairy production in such a marginal environment implies a high degree of risk even by today’s standards. We postulate that this practice was driven by population increase and climate deterioration that put pressure on lowland agropastoral systems and the establishment of more extensive trade networks, leading to greater demand for highly nutritious and transportable dairy products

    Head of State of Exception

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    During the escalation of the “German Autumn” in 1977 the Federal German government resorted to a specific form of crisis management that had been described as an undeclared state of exception. It was Federal chancellor Helmut Schmidt in the first place who oversaw the anti-terrorist measures in the situation room where the executive branch ruled for six weeks beyond any parliamentary control. This article examines the role that Helmut Schmidt had played for the creation of a “subjective state of exception” (Julius Hatschek) and how this could be seen as stemming from Schmidt’s earlier experiences and handling of crisis situations dating back to the 1960s. In this regard it has to be asked with Giorgio Agamben, if in the West German case, the state of exception had become the rule

    Gene therapy for carcinoma of the breast: Pro-apoptotic gene therapy

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    The dysregulation of apoptosis contributes in a variety of ways to the malignant phenotype. It is increasingly recognized that the alteration of pro-apoptotic and anti-apoptotic molecules determines not only escape from mechanisms that control cell cycle and DNA damage, but also endows the cancer cells with the capacity to survive in the presence of a metabolically adverse milieu, to resist the attack of the immune system, to locally invade and survive despite a lack of tissue anchorage, and to evade the otherwise lethal insults induced by drugs and radiotherapy. A multitude of apoptosis mediators has been identified in the past decade, and the roles of several of them in breast cancer have been delineated by studying the clinical correlates of pathologically documented abnormalities. Using this information, attempts are being made to correct the fundamental anomalies at the genetic level. Fundamental to this end are the design of more efficient and selective gene transfer systems, and the employment of complex interventions that are tailored to breast cancer and that are aimed concomitantly towards different components of the redundant regulatory pathways. The combination of such genetic modifications is most likely to be effective when combined with conventional treatments, thus robustly activating several pro-apoptotic pathways
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