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排序方式: 共有3221条查询结果,搜索用时 31 毫秒
981.
982.
Urbanek K Rota M Cascapera S Bearzi C Nascimbene A De Angelis A Hosoda T Chimenti S Baker M Limana F Nurzynska D Torella D Rotatori F Rastaldo R Musso E Quaini F Leri A Kajstura J Anversa P 《Circulation research》2005,97(7):663-673
Cardiac stem cells and early committed cells (CSCs-ECCs) express c-Met and insulin-like growth factor-1 (IGF-1) receptors and synthesize and secrete the corresponding ligands, hepatocyte growth factor (HGF) and IGF-1. HGF mobilizes CSCs-ECCs and IGF-1 promotes their survival and proliferation. Therefore, HGF and IGF-1 were injected in the hearts of infarcted mice to favor, respectively, the translocation of CSCs-ECCs from the surrounding myocardium to the dead tissue and the viability and growth of these cells within the damaged area. To facilitate migration and homing of CSCs-ECCs to the infarct, a growth factor gradient was introduced between the site of storage of primitive cells in the atria and the region bordering the infarct. The newly-formed myocardium contained arterioles, capillaries, and functionally competent myocytes that with time increased in size, improving ventricular performance at healing and long thereafter. The volume of regenerated myocytes was 2200 microm3 at 16 days after treatment and reached 5100 microm3 at 4 months. In this interval, nearly 20% of myocytes reached the adult phenotype, varying in size from 10,000 to 20,000 microm3. Moreover, there were 43+/-13 arterioles and 155+/-48 capillaries/mm2 myocardium at 16 days, and 31+/-6 arterioles and 390+/-56 capillaries at 4 months. Myocardial regeneration induced increased survival and rescued animals with infarcts that were up to 86% of the ventricle, which are commonly fatal. In conclusion, the heart has an endogenous reserve of CSCs-ECCs that can be activated to reconstitute dead myocardium and recover cardiac function. 相似文献
983.
Borini A Lagalla C Cattoli M Sereni E Sciajno R Flamigni C Coticchio G 《Reproductive biomedicine online》2005,10(5):653-668
In spite of recent improvements in IVF, pregnancy rates have not increased significantly and one of the major problems remains the high multiple pregnancy rate. Better criteria are therefore necessary to establish the viability of a transferable embryo. Early prognosis of the developmental fate of the oocyte would help in selecting the best embryos to transfer, but non-invasive selection at the oocyte stage (extracytoplasmic and intracytoplasmic morphology) has proved to be of little prognostic value. Recently, it has been shown that follicular vascularization appears to be predictive of oocyte developmental fate, making it a good first-step approach for selection. Observation of pronuclei patterns at the zygote stage appears to offer an additional prognostic tool, correlating well with IVF outcome. Morphological evaluation of the embryo at days 2-3 remains the most used and valid method of selection, even though it is not sufficient to select embryos with the higher implantation potential. Blastocyst culture is another possible strategy for selecting the best embryos with reduced risk of aneuploidies, though not all major chromosomal aberrations are excluded by prolonged in-vitro culture. In summary, selecting the best embryo for transfer is a decision that should be based on choices made during the different stages of assisted reproductive technologies. 相似文献
984.
Facoetti A Lorusso ML Cattaneo C Galli R Molteni M 《Acta neurobiologiae experimentalis》2005,65(1):61-72
Automatic multimodal spatial attention was studied in 12 dyslexic children (SRD), 18 chronological age matched (CA) and 9 reading level matched (RL) normally reading children by measuring reaction times (RTs) to lateralized visual and auditory stimuli in cued detection tasks. The results show a slower time course of focused multimodal attention (FMA) in SRD children than in both CA and RL controls. Specifically, no cueing effect (i.e., RTs difference between cued-uncued) was found in SRD children at 100 ms cue-target delay, while it was present at 250 ms cue-target delay. In contrast, in both CA and RL controls, a cueing effect was found at the shorter cue-target delay but it disappeared at the longer cue-target delay, as predicted by theories of automatic capture of attention. Our results suggest that FMA may be crucial for learning to read, and we propose a possible causal explanation of how a FMA deficit leads to specific reading disability, suggesting that sluggish FMA in dyslexic children could be caused by a specific parietal dysfunction. 相似文献
985.
Fioredda F Gigliotti AR Haupt R Calevo MG Giudice CL Bocciardo L Giacchino R 《Journal of pediatric hematology/oncology》2005,27(9):481-485
The long-term evolution of hepatitis C virus (HCV) infection in oncologic and/or transplanted patients is still unknown. Patients treated for cancer are different from the general HCV-infected population because of the immunosuppression and the hepatotoxic treatments, which act as co-factors of liver damage. Recently it was observed that antimetabolites play a role in accelerating the process of hepatic fibrosis. The aims of this retrospective study were to describe the clinical course of chronic hepatitis C acquired during anticancer treatment in a group of patients referred to a single center, and to correlate the course of hepatic disease to the type of treatment they received. Among the 17 children who underwent very long follow-up (range 10-18.5 years), the authors identified a group with more active hepatic cytolysis through the serial observation of mean ALT values, HCV RNA determination, and histologic data when available. During follow-up, none of them developed hepatic failure, cirrhosis, or hepatocarcinoma. No single risk factor, such as exposure to antimetabolites, alkylating agents, or other chemotherapy, radiotherapy to the abdomen, exposure to other hepatotoxic drugs, appearance of vaso-occlusive disease, acute and/or chronic graft-versus-host disease, or length of immunosuppression, correlated with a worse course of hepatitis. No definitive conclusions can be drawn. However, multivariate analysis of hepatic risk factors in larger cohorts of patients will be able to provide us with more precise information about the clinical outcome of chronic hepatitis in survivors. 相似文献
986.
Franzese A Brunetti-Pierri N Spagnuolo MI Spadaro R Giugliano M Mukai T Valerio G 《American journal of medical genetics. Part A》2005,135(1):72-74
Mutations in DAX-1 gene cause congenital adrenal hypoplasia (AHC). We present a male patient affected by X-linked adrenal hypoplasia congenita due to a novel DAX-1 missense mutation. The mutation V287G affects the C-terminal end of the DAX-1 protein which plays an important role in functioning of the receptor. In addition, our patient presented an inappropriate tall stature and renal ectopy, which have not been described in AHC so far. 相似文献
987.
988.
Although uncommon in the United States, cryptosporidiosis can be life-threatening in an immunosuppressed host. Rarely, an acute infection of this gastrointestinal illness can present as another disease entity. We present only the third reported case of cryptosporidial infection presenting as acute appendicitis in a 17-year-old HIV+ patient. 相似文献
989.
Cancello R Henegar C Viguerie N Taleb S Poitou C Rouault C Coupaye M Pelloux V Hugol D Bouillot JL Bouloumié A Barbatelli G Cinti S Svensson PA Barsh GS Zucker JD Basdevant A Langin D Clément K 《Diabetes》2005,54(8):2277-2286
In human obesity, the stroma vascular fraction (SVF) of white adipose tissue (WAT) is enriched in macrophages. These cells may contribute to low-grade inflammation and to its metabolic complications. Little is known about the effect of weight loss on macrophages and genes involved in macrophage attraction. We examined subcutaneous WAT (scWAT) of 7 lean and 17 morbidly obese subjects before and 3 months after bypass surgery. Immunomorphological changes of the number of scWAT-infiltrating macrophages were evaluated, along with concomitant changes in expression of SVF-overexpressed genes. The number of scWAT-infiltrating macrophages before surgery was higher in obese than in lean subjects (HAM56+/CD68+; 22.6 +/- 4.3 vs. 1.4 +/- 0.6%, P < 0.001). Typical "crowns" of macrophages were observed around adipocytes. Drastic weight loss resulted in a significant decrease in macrophage number (-11.63 +/- 2.3%, P < 0.001), and remaining macrophages stained positive for the anti-inflammatory protein interleukin 10. Genes involved in macrophage attraction (monocyte chemotactic protein [MCP]-1, plasminogen activator urokinase receptor [PLAUR], and colony-stimulating factor [CSF]-3) and hypoxia (hypoxia-inducible factor-1alpha [HIF-1alpha]), expression of which increases in obesity and decreases after surgery, were predominantly expressed in the SVF. We show that improvement of the inflammatory profile after weight loss is related to a reduced number of macrophages in scWAT. MCP-1, PLAUR, CSF-3, and HIF-1alpha may play roles in the attraction of macrophages in scWAT. 相似文献
990.
Giardiosis in domestic ruminants is an important parasitic disease and it has been shown to impair growth in lambs, thus constituting a disease of economic concern. In Europe, surveys on the prevalence of giardiosis in sheep are limited. In order to obtain additional information on the presence of giardiosis and on the potential zoonotic role of Giardia duodenalis affecting sheep in central Italy, faecal samples of 325 native sheep from 20 farms in Abruzzo region (Italy) were examined for the presence of Giardia and the isolates were genotyped and sequenced. G. duodenalis cysts were detected in five of the 325 sheep (1.5%) (mean of 450 cysts/g) coming from two farms. The 770-bp fragment of the glutamate dehydrogenase gene and the 753-bp fragment of the -giardin gene showed 100% homology with the Assemblage AI. This work suggests for the first time in Italy that sheep carry a Giardia genotype, which can be a potential public health hazard. 相似文献