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21.
The angiographic analogue of the sunburst, (right angle) periosteal new bone formation in osteogenic sarcoma is described. The angiographic findings in this tumor and their relationship to the pathologic appearance are discussed.  相似文献   
22.
PURPOSE: This study aims to investigate the role of gastrin-17 (G17) on angiogenesis features in gliomas both in vitro and in vivo. EXPERIMENTAL DESIGN: The influences of G17 and G17 receptor antagonists were characterized in vitro in terms of angiogenesis on human umbilical vein endothelial cell (HUVEC) tubulogenesis processes on Matrigel and in vivo with respect to U373 orthotopic glioma xenografts. The influence of phosphatidylinositol 3'-kinase, protein kinase C, and nuclear factor-kappaB inhibitors was characterized in vitro on G17-mediated HUVEC tubulogenesis. G17-mediated release of interleukin (IL)-8 from HUVECs and G17-induced modifications in nuclear factor-kappaB DNA binding activity were characterized by means of specific enzyme-linked immunosorbent assays. The influence of G17 on E- and P-selectin expression was determined by means of computer-assisted microscopy, whereas the influence of E- and P-selectin on HUVEC migration was approached by means of antisense oligonucleotides. The chemotactic influence of G17 and IL-8 on HUVEC migration was characterized by means of computer-assisted videomicroscopy with Dunn chambers. RESULTS: Messenger RNAs for cholecystokinin (CCK)A, CCKB, and CCKC receptors were present in HUVECs and microvessels dissected from a human glioblastoma. Whereas G17 significantly increased the levels of angiogenesis in vivo in the U373 experimental glioma model and in vitro in the HUVECs, the CCKB receptor antagonist L365,260 significantly counteracted the G17-mediated proangiogenic effects. G17 chemoattracted HUVECs, whereas IL-8 failed to do so. IL-8 receptor alpha (CXCR1) and IL-8 receptor beta (CXCR2) mRNAs were not detected in these endothelial cells. Gastrin significantly (but only transiently) decreased the level of expression of E-selectin, but not P-selectin, whereas IL-8 increased the expression of E-selectin. Specific antisense oligonucleotides against E- and P-selectin significantly decreased HUVEC tubulogenesis processes in vitro on Matrigel. CONCLUSIONS: The present study shows that gastrin has marked proangiogenic effects in vivo on experimental gliomas and in vitro on HUVECs. This effect depends in part on the level of E-selectin activation, but not on IL-8 expression/release by HUVECs.  相似文献   
23.
The aim of the study was to determine the effects of early postnatal PCP treatment on the sensitivity of pubertal and adult rats to lindane proepileptogenic effects. Rat pups were treated with NaCl (0.9%) or PCP (10 mg/kg) at postnatal days 2, 6, 9 and 12. One control (NaCl-35) and one experimental (PCP-35) group have received lindane (4 mg/kg) at postnatal day 35, while others received lindane at postnatal day 65 (NaCl-65 and PCP-65). One week prior to lindane treatment three gold-plated EEG electrodes were implanted. Pubertal rats had significantly shorter latency time. After lindane, a prompt increase in power spectral density seen in PCP-treated groups vs. control was evident earlier in PCP-65 rats. The theta waves were significantly increased in PCP-35 and alpha rhythm in PCP-65 rats, when compared with corresponding controls. Postnatal PCP treatment increases the synchronization of brain electrical activity, thus contributing to the increased susceptibility to lindane.  相似文献   
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The general microscopic characteristics of nerves are described in several textbooks of histology, but the specific microanatomies of most nerves that can be blocked by anesthesiologists are usually less well known. Our objective was to evaluate the 3D reconstruction of nerve fascicles from optical projection tomography images (OPT) and the ability to undertake an internal navigation exploring the morphology in detail, more specifically the fascicular interconnections. Median and lingual nerve samples were obtained from five euthanized piglets. OPT images of the samples were acquired and 3D reconstruction was performed. The OPT technique revealed the inner structure of the nerves at high resolution, including large and small fascicles, perineurium, interfascicular tissue, and epineurium. The fascicles were loosely packed inside the median nerve and more densely so in the lingual nerve. Analysis of the 3D models demonstrated that the nerve fascicles can show six general spatial patterns. Fascicular interconnections were clearly identified. The 3D reconstruction of nerve fascicles from OPT images opens a new path for research into the microstructure of the inner contents of fascicular nerve groups and their spatial disposition within the nerve including their interconnections. These techniques enable 3D images of partial areas of nerves to be produced and could became an excellent tool for obtaining data concerning the 3D microanatomy of nerves, essential for better interpretation of ultrasound images in clinical practice and thus avoiding possible neurological complications. Clin. Anat. 31:424–431, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
26.
Objective: To examine how medical journal editors perceive changes in transparency and credibility of industry-sponsored clinical trial publications over a 5 year period (2010 to 2015).

Methods: From July to September 2015, a survey link was emailed to journal editors identified from the Thomson Reuters registry. Editors ranked their perception of: a) change in transparency and credibility of industry-sponsored clinical trial publications; b) 8 “Publication Best Practices” and the impact of each on transparency; and c) the importance and adoption of the previously published “10 Recommendations for Closing the Credibility Gap in Reporting Industry-Sponsored Clinical Research”.

Results: Of 510 editors who opened the survey, the analysis pool comprised a total of 293 editors. The majority of respondents reported their location as the US (46%) or EU (45%) and most commonly reported editorial titles were deputy/assistant editor (36%), editor-in-chief (35%) and section editor (24%). More editors reported improved versus worsened transparency (63.5% vs. 6.1%) and credibility (53.2% vs. 10.4%). Best practices that contributed most to improved transparency were “disclosure of the study sponsor” and “registration and posting of trial results”. Respondents ranked the importance of nine recommendations as moderate or extremely important, and adoption of all recommendations was ranked minimal to moderate.

Conclusions: The 293 editors who responded perceived an improvement in the transparency and credibility of industry-sponsored publications from 2010 to 2015. Confirmation of the importance of 9/10 recommendations by the respondents was encouraging. Yet, low adoption rates suggest that additional work is required by all stakeholders to improve best practices, transparency and credibility.  相似文献   

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28.
Rare earth atoms exhibit several interesting properties, for example, large magnetic moments and luminescence. Introducing these atoms into a different matrix can lead to a material that shows multiple interesting effects. Holmium atoms were incorporated into an iron oxide nanoparticle and the concentration of the dopant atom was changed in order to determine its influence on the host crystal. Its magnetic and magneto-optical properties were investigated by vibrating sample magnetometry and Faraday rotation measurements. The luminescent characteristics of the material, in solution and incorporated in a polymer thin film, were probed by fluorescence experiments.  相似文献   
29.
Purpose: Adipose tissue expansion can occur through several different ways and, under certain conditions, can be connected with chronic inflammation. TNF-α is one of the important cytokines involved in this process. Prolonged inflammation in obesity can lead to obesity-related insulin resistance and tissue dysfunction. The aim of our study was to investigate how different combination of maternal and postnatal diet affects offspring adipose tissue morphology and adipose tissue TNF-α expression.

Methods: Ten female Sprague Dawley rats, 9 weeks old, were randomly divided into two groups and fed either standard laboratory chow or food rich in saturated fatty acids during 6 weeks and then mated with the same male rat. After birth and lactation male rat offspring from both groups were divided into four subgroups depending on the diet they were fed until 22 weeks old. Samples of white adipose tissue were taken from the subcutaneous, epididymal, and perirenal fat pad. On tissue sections, histomorphometric analysis was conducted using CellProfiler program v 2.1.1, and immunohistochemical staining for TNF-α was performed.

Results: Greater mean surface area of subcutaneous and epididymal adipocytes was found in groups of male rat offspring with altered diet. In perirenal adipose tissue, the highest number of adipocytes was measured in the group where both mother and offspring were fed a high-fat diet. Adipocyte staining intensity for TNF-α did not differ significantly between the groups.

Conclusions: Together with our previously published data, our results lead to the conclusion that alteration of postnatal diet can lead to TNF-α and adipocyte morphology changes.  相似文献   

30.
We present a case which reports the occurrence of a potential elevation of Tacrolimus (Tac) plasma levels to toxic values in a renal transplant recipient after adding Metronidazole (Met) to the medication regimen. A 30-year old female, status post living-related renal transplant, who was stabilized on Tac 4.5 mg, twice daily, for 4 months, presented to the clinic with diarrhea. We used Microparticle Enzyme Immunoassay (MEIA) to determine Tac trough concentration (trough concentrations 5–10 ng/ml). After 6 days of Met therapy on 1.5 g/d, Tac trough concentration and serum creatinine (sCr) increased to 20.2 ng/ml and 7.8 mg/dl respectively. Met therapy was discontinued, also one dose of Tac was withheld, while daily dose was decreased to 2 mg/d. Four days after Met discontinuation, Tac concentration dropped to 8.7 ng/ml, sCr to 2.1 mg/dl, warranting Tac dose increase to 3 mg/d. Co-administration of Tac with Met may result in elevated Tac concentrations, possibly leading to tacrolimus nephrotoxicity. Clinicians should be aware of this potential interaction and closely monitor Tac concentration and renal function.  相似文献   
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