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61.
Tumor lymphangiogenesis in inflammatory breast carcinoma: a histomorphometric study. 总被引:11,自引:0,他引:11
Ilse Van der Auwera Gert G Van den Eynden Cecile G Colpaert Steven J Van Laere Peter van Dam Eric A Van Marck Luc Y Dirix Peter B Vermeulen 《Clinical cancer research》2005,11(21):7637-7642
PURPOSE: At the time of diagnosis, metastatic dissemination of tumor cells via the lymphatic system has occurred in nearly all patients with inflammatory breast cancer (IBC). The objective of this study was twofold: (a) to determine which is the most suitable marker of lymph vessels in primary breast tumors and (b) to compare histomorphometric lymph vessel variables in IBC and non-IBC. EXPERIMENTAL DESIGN: Serial sections of 10 IBCs and 10 non-IBCs were immunostained for D2-40, LYVE-1, podoplanin, and PROX-1. Relative lymph vessel area, lymph vessel perimeters, and counts and lymphatic endothelial cell proliferation (LECP) were then measured in D2-40/Ki-67 double-immunostained sections of 10 normal breast tissues, 29 IBCs, and 56 non-IBCs. RESULTS: D2-40 was the most suitable antibody for staining peritumoral and intratumoral lymph vessels. D2-40-stained intratumoral lymph vessels were present in 80% of non-IBCs and 82.8% of IBCs (P = 0.76). In non-IBC, lymph vessels located in the tumor parenchyma were smaller and less numerous than those at the tumor periphery (P < 0.0001) whereas in IBC, intratumoral and peritumoral variables were not significantly different. The mean relative tumor area occupied by lymph vessels was larger in IBC than in non-IBC (P = 0.01). LECP at the tumor periphery was higher in IBC than in non-IBC: median LECP was 5.74% in IBC versus 1.83% in non-IBC (P = 0.005). CONCLUSIONS: The high LECP in IBC suggests that lymphangiogenesis contributes to the extensive lymphatic spread of IBC. 相似文献
62.
It has been argued in previous issues of this journal that health technology assessment can be used as a tool to assess the efficiency of pharmaceutical care by linking its impact on clinical and humanistic outcomes to the resources required to achieve these outcomes. Additionally, as policy-makers appreciate the need to evaluate projects on the basis of their costs and benefits, the application of health technology assessment to pharmaceutical care may serve as a way of communicating with policy-makers and informing policy on pharmaceutical care.This article elaborates on this idea by arguing that policy-makers will be more likely to appreciate the value of pharmaceutical care if researchers pay more attention to some methodological principles underlying health technology assessment in the context of pharmaceutical care, and if they take into account the decision-making context facing policy-makers. In order to raise the methodological quality of studies, researchers need to take care to define better the pharmaceutical care intervention; to evaluate the costs of the intervention and its impact on the utilization of other health services; and to aggregate the various clinical and humanistic outcome measures that are commonly used in this type of research. In order to increase the usefulness of study findings to policy-makers, researchers need to identify the multiple objectives that policy-makers pursue, and show how study findings will aid policy-makers in attaining these objectives. 相似文献
63.
Adrienne Elisabeth van der Hoeven Rolf Fronczek Mink Sebastian Schinkelshoek Frederik Willem Cornelis Roelandse Jaap Adriaan Bakker Sebastiaan Overeem Denise Bijlenga Gert Jan Lammers 《Sleep》2022,45(5)
Study ObjectivesThe diagnosis of narcolepsy type 1 (NT1) is based upon the presence of cataplexy and/or a cerebrospinal fluid (CSF) hypocretin-1/orexin-A level ≤ 110 pg/mL. We determined the clinical and diagnostic characteristics of patients with intermediate hypocretin-1 levels (111–200 pg/mL) and the diagnostic value of cataplexy characteristics in individuals with central disorders of hypersomnolence.MethodsRetrospective cross-sectional study of 355 people with known CSF hypocretin-1 levels who visited specialized Sleep-Wake Centers in the Netherlands. For n = 271, we had full data on cataplexy type (“typical” or “atypical” cataplexy).ResultsCompared to those with normal hypocretin-1 levels (>200 pg/mL), a higher percentage of individuals with intermediate hypocretin-1 levels had typical cataplexy (75% or 12/16 vs 9% or 8/88, p < .05), and/or met the diagnostic polysomnographic (PSG) and Multiple Sleep Latency Test (MSLT) criteria for narcolepsy (50 vs 6%, p < .001). Of those with typical cataplexy, 88% had low, 7% intermediate, and 5% normal hypocretin-1 levels (p < .001). Atypical cataplexy was also associated with hypocretin deficiency but to a lesser extent. A hypocretin-1 cutoff of 150 pg/mL best predicted the presence of typical cataplexy and/or positive PSG and MSLT findings.ConclusionIndividuals with intermediate hypocretin-1 levels or typical cataplexy more often have outcomes fitting the PSG and MSLT criteria for narcolepsy than those with normal levels or atypical cataplexy. In addition, typical cataplexy has a much stronger association with hypocretin-1 deficiency than atypical cataplexy. We suggest increasing the NT1 diagnostic hypocretin-1 cutoff and adding the presence of clearly defined typical cataplexy to the diagnostic criteria of NT1. Clinical trial information: This study is not registered in a clinical trial register, as it has a retrospective database design. 相似文献
64.
Markus Wertz Michael Benno Schmidt Hieronymus Hoelzig Maximilian Wagner Bernd Abel Gert Kloess Sebastian Hahnel Andreas Koenig 《Materials》2022,15(13)
In the study the influence of different dental technical tools on the surface temperature and phase composition of fixed dental prostheses (FDPs) made of yttria-partially stabilized zirconia polycrystals (3Y-/4Y-/5Y-PSZ) was investigated. FDPs were fabricated by using computer-aided manufacturing (CAM). The FDPs were treated with a contra-angle handpiece equipped with different burs and polishers. The resulting surface temperatures were measured with a thermographic camera, and the resulting phase transformations were investigated by X-ray diffraction and quantified by Rietveld refinement. Processing with burs resulted in no phase transformation, but a preferred orientation shift. Using coarse polisher induced a phase transformation to the rhombohedral phase, while fine polishers produced no relevant phase transformations and no preferred orientation shift. Compared to the monoclinic phase (ca. 9% theoretical volume increase), which is associated with low-temperature degradation (LTD), the rhombohedral phase is much more voluminous (ca. 15% theoretical volume increase) and distorted and, therefore, has a greater degradation potential. 相似文献
65.
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67.
Antje Ludwig Nicoline Jochmann Andras Kertesz Claudia Kuhn Simone Mueller Christine Gericke Gert Baumann Karl Stangl Verena Stangl 《BMC women's health》2010,10(1):1-8
Background
Decreased levels of circulating bone marrow-derived progenitor cells have been associated with risk factors and cardiovascular diseases. Smoking is the most important modifiable risk factor for atherosclerosis in young women. The aim of this pilot study was to assess in healthy premenopausal women without other risk factors for cardiovascular disease the influence of nicotine abuse on the number of circulating progenitor cells in relation to endothelial function.Methods
The number of endothelial progenitor cells, measured as colony-forming units in a cell-culture assay (EPC-CFU) and the number of circulating CD34 + and CD34 +/CD133 + cells, measured by flow cytometry, was estimated in 32 women at the menstrual phase of the menstrual cycle. In addition, flow-mediated dilation (FMD) was assessed as a marker for vascular function. In a subgroup of these women (n = 20), progenitor cells were also investigated at the mid-follicular and luteal phases of the menstrual cycle.Results
Compared to non-smokers, the abundance of circulating CD34 + cells was significantly lower in smoking women in the menstrual, mid-luteal, and mid-follicular phases of the menstrual cycle. The number of CD34 + progenitor cells was revealed to have significant positive correlation with FMD in young healthy women, whereas CD34 +/CD133 + progenitor cells and EPC-CFU showed no significant correlation.Conclusion
The number of CD34 + progenitor cells positively correlates with FMD in young healthy women and is decreased by smoking. 相似文献68.
Juliane Kager Jochen Schneider Sebastian Rasch Peter Herhaus Mareike Verbeek Carolin Mogler Albert Heim Gert Frsner Dieter Hoffmann Roland M. Schmid Tobias Lahmer 《Viruses》2022,14(7)
Human adenovirus (HAdV) can often lead to fulminant hepatitis in immunocompromised patients, mostly after reactivation of HAdV. Different risk factors, e.g., transplantation and chemotherapy, increase the risk of developing a HAdV hepatitis. We retrospectively analyzed three patients who showed the characteristics of a HAdV hepatitis observed in disseminated disease. In addition to PCR, diagnosis could be proven by pathology, CT scan, and markedly elevated transaminases. All patients had a hemato-oncologic underlying disease. Two had received a stem-cell transplant, and one was under chemotherapy including rituximab. Despite therapy with cidofovir, all patients died. As the incidence of HAdV hepatitis is low, diagnosis may be easily overlooked. No treatment approaches have yet been established. HAdV hepatitis should be considered as a differential diagnosis, especially when risk factors are present. To avoid dissemination, treatment should be initiated as soon as possible. 相似文献
69.
Henk M M L De Feyter Gert Schaart Matthijs K Hesselink Patrick Schrauwen Klaas Nicolay Jeanine J Prompers 《Magnetic resonance in medicine》2006,56(1):19-25
1H MR spectroscopy (MRS) has proved to be a valuable noninvasive tool to measure intramyocellular lipids (IMCL) in research focused on insulin resistance and type II diabetes in both humans and rodents. An important determinant of IMCL is the muscle fiber type, since oxidative type I fibers can contain up to three times more IMCL than glycolytic type II muscle fibers. Because these different muscle fiber types are inhomogeneously distributed in rodent muscle, in the present study we investigated the distribution of IMCL within the rat tibialis anterior muscle (TA) in vivo using single-voxel 1H MRS along with the muscle fiber distribution in the TA ex vivo determined from immunohistological assays. IMCL levels in the TA differed by up to a factor of 3 depending on the position of the voxel. The distribution of IMCL over the TA cross section was not random, but emerged in a pattern similar to the distribution of the predominantly oxidative muscle fiber types. Dietary interventions, such as high-fat feeding and 15 hr of fasting, did not significantly change this typical fiber type-dependent pattern of IMCL content. These results stress the importance of voxel positioning when single-voxel 1H MRS is used to study IMCL in rodent muscle. 相似文献
70.
Health promotion (HP) amongst older people is an increasingly prominent policy concern for governments. The development of an evidence-base and the advocacy of effective interventions in the light of this act as legitimation tools for the overall HP phenomenon – assisting the growth of state and non-state funding for public health initiatives for older people. In structuring decision-making as to which individual projects/initiatives receive funding, frameworks for acknowledging efficacy impact on formats of HP work both positively and negatively. Drawing on recent research across the EU and focusing on the specific national contexts of Austria and England, this comparative policy analysis triangulates best-practice modelling, evaluation data and interviews with project coordinators to explore how policy contexts impact on the nature and format of HP interventions. Amidst a developing awareness of what effective practice looks like, successful HP initiatives must advocate their legitimacy within narrow rules of quality, where measurable outcomes have become the keys which unlock financial resources. Findings across both countries suggest that this instrumentalisation of legitimation, driven by economic pressures and bureaucratic generalisability, threatens the rationality of HP. From a Habermasian perspective, tensions emerge between projects’ remaining reflexive towards processes and their need to articulate the ‘success’ of the interventions in a language of outcomes. Over time, in an era where resources are increasingly scarce and competition over these intensifies, a danger exists whereby the instrumentality of HP begins to separate from, and impinge upon, the capacity for projects to think and act holistically. 相似文献