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排序方式: 共有1023条查询结果,搜索用时 15 毫秒
1.
G. Burastero N. Sessarego G. Grappiolo C. Castellazzo S. Castello A. Pitto G. Cittadini M. Podesta G. Bovio M. Peresi E. Fulcheri F. Frassoni L. Spotorno 《Journal of orthopaedics and traumatology》2007,8(1):49-54
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several
proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro
and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action
on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group
G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated
with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging
between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed
by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like
structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly
superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological
study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the
healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate
the best dosage. 相似文献
2.
Laipcarpine (LC), a pyorrolizidine alkaloid, is able to inducea series of chronic and progressive lesions in rat liver, includingalong-lasting block in the cell cycle, the appearance of enlargedhepatocytes (megalocytosis), fibrosis, cirrhosis and malignantneoplasms. In this study the effect of transplantation of normalhepatocytes on the development of LC (80 µmol/kg i.p.).Four weeks later all animals were subjected to 2/3 paroticlhepatectomy (PH). In addition, at the time of PH one group ofrats were transplanted with normal hepatocytes isolated froma syngeneic donor (106 cells/rat via the portal vein), whilethe other group received only the culture medium. All rats werekilled 14 weeks after the operation. Grossly, the liver of ratsexposed to LC followed by PH with no transplantation of normalhepatocytes was small in size (% liver wt/body wt 1.66 ±0.08) and exhibited a few whitish nodules. Histologically, 相似文献
3.
Ezio Martuscelli Clara Silvestre Maurizio Canetti Claudia de Lalla Anna Bonfatti Alberto Seves 《Macromolecular chemistry and physics.》1989,190(10):2615-2625
The crystallization and the thermal behaviour of thin films of isotactic polypropylene/hydrogenated oligo(cyclopentadiene) of low molecular weight (iPP/HOCP) are studied using optical microscopy and differential scanning calorimetry (DSC). The spherulite growth rate, the overall crystallization rate and the equilibrium melting temperature of iPP are decreased by the addition of HOCP to iPP. This leads to the hypothesis that iPP and HOCP form a miscible blend in the amorphous phase. This hypothesis is also supported by the detection of a single blend-composition-dependent glass transition temperature of each blend as determined by DSC. 相似文献
4.
Maurizio Avella Ezio Martuscelli Gaetano Della Volpe Annalaura Segre Enrico Rossi Tonino Simonazzi 《Macromolecular chemistry and physics.》1986,187(8):1927-1943
The crystallization and thermal behaviour of crystallizable random propene/ethene copolymers (P-co-E) was systematically investigated. Index of crystallinity and, index of γ-form, enthalpy and entropy of fusion, equilibrium melting temperature, spherulite growth rate, and overall kinetic rate constant were determined and correlated with the overall ethene content and with the concentration of specific chemical defects as determined by 13C NMR analysis (PEP, EPP, EPE triads). The samples of the copolymers, obtained with very-high-yield Ziegler-Natta catalysts, were characterized by IR, 13C NMR, wide angle X-ray scattering, and differential scanning calorimetry. 相似文献
5.
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7.
Angela Pucci MD Ezio David MD Michele di Summa MD Enrico Donegani MD Valeria Ghisetti MD Mario Morea MD Franco Mollo MD 《Cardiovascular pathology》1993,2(4):259-261
Dissecting aneurysms of coronary arteries are a rare finding and have never been reported in a cardiac allograft. We found two spontaneous dissecting aneurysms on the middle third of both the left anterior descending and the right coronary arteries in a female cardiac transplantation recipient. She died 43 days after cardiac transplantation after developing human cytomegalovirus pneumonia and pancreatitis. Dissecting coronary aneurysms, microfoci of subendocardial coagulative necrosis, and area of subepicardial dystrophic calcifications were discovered at necropsy examination. 相似文献
8.
Thomas Hoffman Anil K. Tripathi Young Lim Lee Elaine F. Lizzio Ezio Bonvini 《Inflammation》1992,16(6):571-585
Human monocytes released superoxide anion, prostaglandin E2, leukotriene B4, IL-1, and TNF when exposed to plastic surfaces coated with murine anti-CD3 monoclonal antibody, OKT 3. Stimulation of mediator release by OKT 3 was dependent on the amount of antibody immobilized onto wells of plastic tissue culture plates. Soluble antibody or antibody adsorbed to monocytes and reacted with an aggregating (cross-linking) second antibody failed to induce mediator release. Monocytes armed with OKT 3 formed rosettes with T cells in a fashion indistinguishable from that seen between monocytes and T cells sensitized with OKT 3. Monocytes with adsorbed OKT 3 antibodies released IL-1 and TNF- when exposed to unsensitized T cells, although increased superoxide release could not be detected. OKT 4a, a murine IgG2a antibody that reacts with a different T cell epitope (CD4), failed to induce cytokine release from monocytes when cross-linked by T cells or a CD4+ T cell line, even in the presence of IL-2 or IFN-. These data indicate that certain antibodies bound to Fc receptors (FcR) of monocytes may trigger monocyte function when reacting with cells bearing the appropriate target antigens. FcR-mediated signaling resulting in mediator release may be involved in initiating or regulating the immune response. Furthermore, systemically administered monoclonal antibodies may induce inflammatory responses and their attendant symptomatologies via their interaction with FcR-bearing inflammatory cells. 相似文献
9.
Patrizia Sadocco Chiara Bulli Graziano Elegir Alberto Seves Ezio Martuscelli 《Macromolecular chemistry and physics.》1993,194(10):2675-2686
The biodegradability of solution-cast films of poly(D (–)-3-hydroxybutyrate) (PHB) blended with the melt-compatible component atactic poly(epichlorohydrin) (aPECH) was investigated. A bacterium which produced extracellular enzymes that degraded PHB even when blended with aPECH was isolated, and tentatively designated as Aureobacterium saperdae. The growth rate of A. saperdae decreased with increasing aPECH content in the blend, up to films containing 60 wt.-% aPECH, at which composition growth was completely inhibited. The decrease in the bacterial growth rate could be due to the dilution of PHB molecules on the blend film surface caused by the presence of aPECH molecules. At the stationary phase of bacterial growth the percentage of weight loss of blend films decreased with increasing aPECH fraction, which was probably due to the lower accessibility of PHB when blended with aPECH. During the bacterial growth only PHB was metabolized, whereas neither degradation nor abiotic release of aPECH was detected for blend films. 相似文献
10.
M P Foschini E Fulcheri P Baracchini C Ceccarelli C M Betts V Eusebi 《Human pathology》1990,21(8):859-865
Three cases of a squamous cell carcinoma with a prominent myxoid stroma are reported. One case in a 70-year-old woman had presented as a lump in the breast, the other two presented as polypoid lesions of the larynx and cervix uteri in a 65-year-old man and 61-year-old woman, respectively. The carcinomatous component was immersed in abundant extracellular mucosubstances. In addition to occasional squamous pearls, it displayed immunocytochemical evidence of high-weight keratin present in the neoplastic cells and, in one case, desmosomal attachment under electron microscopy. The extracellular mucosubstances proved to be similar to those seen in connective tissue. The differential diagnosis with histologically similar lesions has been taken into consideration, and it has been suggested that this newly described entity showing abundant myxoid stroma has to be distinguished from numerous benign and malignant myxoid soft tissue tumors. 相似文献