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排序方式: 共有322条查询结果,搜索用时 31 毫秒
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Structural and functional differentiation of sinusoidal endothelial cells during liver organogenesis in humans 总被引:2,自引:1,他引:2
During fetal life, human liver sinusoids, which differentiate between 4 and 12 weeks of gestation from capillaries of the septum transversum, must support an important hematopoietic function and acquire the structural and functional characteristics of adult sinusoids. To gain insight into their differentiation process, we studied the expression of (1) markers of continuous endothelia, absent from adult sinusoidal endothelial cells (PECAM-1, CD34, and 1F10); (2) functional markers of adult sinusoidal endothelial calls (CD4, 1CAM-1, CD32, and CD14); and (3) extracellular matrix components (laminin, tenascin, fibronectin, and thrombospondin) in 37 fetuses of different gestational ages. We identified two successive differentiation events. (1) An early structural differentiation, occurring from 5 to 12 weeks of gestation, was characterized by the loss of continuous endothelial cell markers and a reduction in the perisinusoidal amount of laminin and in the deposition of tenascin, fibronectin, and thrombospondin; at the end of this process, fetal liver sinusoids present structural characteristics comparable to those of the sinuses in adult hematopoietic bone marrow. (2) A later functional differentiation was characterized by the acquisition of the markers of adult sinusoidal endothelial cells, initiating at 10 weeks of gestation and completed by 20 weeks of gestation; this process likely contributes to adapt liver sinusoids to the specific functions of the adult hepatic tissue. 相似文献
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Giandomenico Roviello Edoardo Francini Armando Perrella Letizia Laera Maria Antonietta Mazzei Susanna Guerrini Franco Roviello Daniele Marrelli Roberto Petrioli 《Cancer biology & therapy》2015,16(4):493-497
Bevacizumab and Tamoxifen are valid therapeutic options for metastatic breast cancer (mBC) patients. In this report, we describe a 47 year old woman with mBC successfully treated with a maintenance therapy with Bevacizumab+Tamoxifen. A maintenance approach using 2 different drugs with different targets and mechanism of action, such as anti-angiogenic and anti-hormonal treatment is particularly intriguing because they affect different pathways involved in mBC progression. Further studies including a large number of patients are needed, in order to select women who could benefit from this maintenance approach. 相似文献
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C Varo A Murru E Salagre E Jiménez B Solé L Montejo AF Carvalho B Stubbs I Grande A Martínez-Arán E Vieta M Reinares 《European neuropsychopharmacology》2019,29(1):76-97
Clinical and epidemiological research suggests that behavioral addictions (BA) are associated with a wide range of psychiatric disorders. However, the relationship between BA and bipolar disorders (BD) has not been thoroughly explored. The aim of this systematic review was to critically summarize and evaluate the current available evidence regarding a possible association between BA and BD. A systematic review of major electronic databases according to PRISMA guidelines was conducted from inception to 31st December 2017. We sought quantitative studies data concerning prevalence of comorbidity, features and treatment related to BA-BD comorbidity. Data were narratively synthesized. Of the 1250 studies returned from the search, a total of 28 articles were included in this review. BA may be overrepresented in BD samples, and the other way around. Pathological gambling and kleptomania were the most prevalent conditions followed by compulsive buying, compulsive sexual behavior and internet addiction. BA was also associated with other mood disorders, anxiety disorders and substance use disorder. BD-BA comorbidity was related with more severe course of illness. Studies on treatment strategies for BD–BA comorbidity are rather limited; only one randomized controlled trial that fulfilled inclusion criteria was identified. Methodological heterogeneity in terms of design and results among studies was found. BD-BA commonly co-occurs although there is a need for rigorous studies. Routine screening and adequate assessment may be helpful in BD patients to identify individuals at risk for BA and to effectively manage the complex consequences associated with BA-BD comorbidity. 相似文献
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Pascali C Bogni A Fugazza L Cucchi C Crispu O Laera L Iwata R Maiocchi G Crippa F Bombardieri E 《Nuclear medicine and biology》2012,39(4):540-550
Introduction3′-Deoxy-3′-[18F]fluorothymidine ([18F]FLT) shows great potential as a tracer for proliferative studies with PET. However, its regular application is often limited by low radiochemical yields and the use of a troublesome HPLC separation. Moreover, a high content of ethanol, at least one-fold higher than the European Pharmacopoeia and US Pharmacopoeia's established limit, is always present in the final product. The present study reports an optimization of the reaction conditions and a simple and straightforward purification step which affords a solution of [18F]FLT suitable for human use.MethodsSeveral conditions and materials were tested for both the nucleophilic substitution and purification step. The latter was achieved by means of a series of commercial solid-phase extraction cartridges. Very conveniently, the whole one-pot synthesis was carried out on commercial automated modules using basically the same setup employed for the synthesis of [18F]FDG.ResultsUnder routine conditions, radiochemical yields of 37% [decay-corrected to start of synthesis (SOS)] were achieved in ca. 39 min from SOS, with radiochemical purities >98% (usually >99%). The negligible radiolysis observed could be easily suppressed by adding 0.5% of EtOH. Typical unlabelled chemical impurities detected were thymidine (0.15 ppm), thymine (0.28 ppm) and stavudine (0.05 ppm).ConclusionsA reliable, simple and efficient preparation of [18F]FLT has been developed, able to afford an ethanol-free solution of the tracer with no need for any HPLC purification. Because of its similarity to the [18F]FDG synthesis, the method can be readily implemented on basically all the commercial modules developed for this common radiotracer. 相似文献
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We report on data collected in a sample of 194 schoolchildren (9–13 years of age) residing in a mountainous community in Ecuador. This study was part of an ongoing epidemiological inquiry into the prevalence of parasitism, malnutrition, neurocysticercosis, goitre, iodine levels and EEG abnormalities, and the relationships among these factors. Data were obtained by a local medical team supported by specialized personnel. The results showed that 34% of the EEG tracings were abnormal, with higher rates among girls. The best fitted log-linear model to explain the results was the combination of EEG status, parasite infection, goitre and gender. The best predictor of EEG abnormalities was found to be a diagnosis of goitre. 相似文献
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Saleh MN; Goldman SJ; LoBuglio AF; Beall AC; Sabio H; McCord MC; Minasian L; Alpaugh RK; Weiner LM; Munn DH 《Blood》1995,85(10):2910-2917
The small subset of circulating monocytes that express the maturation- associated CD16 antigen has recently been reported to be elevated in patients with bacterial sepsis. We now show that this novel CD16+ monocyte population is also spontaneously expanded in patients with cancer. We studied 14 patients with metastatic gastrointestinal carcinoma enrolled ina clinical trial of recombinant human macrophage colony-stimulating factor (rhMCSF) plus monoclonal antibody D612. We found that before any cytokine treatment, 12 of 14 patients constitutively displayed significant elevations in both the percentage and the absolute number of CD16+ monocytes, as compared with both normal subjects and ill patients with elevated monocyte counts but without malignancy. CD16+ monocytes accounted for 46% +/- 22% of total monocytes in the patients with cancer versus 5% +/- 3% for controls (P < .01). The increase was not attributable to infection or intercurrent illness and appeared to be associated with the underlying malignancy itself. A similar spontaneous elevation of CD16+ monocytes was observed in 35 of 44 additional patients diagnosed with a variety of other solid tumors. When patients with gastrointestinal carcinoma were treated with rhMCSF, there was a marked further increase in the percentage of CD16+ monocytes (to 83% +/- 11%), as well as in the absolute number of CD16+ cells and the level of CD16 antigen expression. In every case, the patients with cancer showed a greater CD16+ monocyte response than the maximal response obtained in normal volunteer subjects treated witha similar regimen of rhMCSF (n = 5, P < .001), suggesting that the presence of malignancy primed patients for enhanced responsiveness to rhMCSF. We hypothesize that spontaneous expansion of the CD16+ monocyte population may represent a novel biologic marker for a widespread and previously unsuspected host immune response to malignancy. 相似文献
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