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排序方式: 共有930条查询结果,搜索用时 15 毫秒
11.
C Lestuzzi G L Nicolosi R Mimo D Pavan D Zanuttini 《The American journal of cardiology》1992,70(2):247-251
Mediastinal paracardiac tumors may cause both cardiovascular complications and problems in differential diagnosis of cardiac diseases. Transesophageal echocardiography (TEE) may give an additional new window to mediastinal neoplasms, but only a few studies have been reported. TEE was performed in 70 patients with paracardiac neoplastic masses. The procedure was indicated to solve particular clinical problems in 20 patients, and as a prospective study on 50 unselected patients with mediastinal neoplasms. Twenty-three patients underwent follow-up studies; a total of 101 echocardiograms were recorded. The procedure was tolerated well or very well by most patients, and provided additional anatomic or hemodynamic data in every patient in group a and in 45 of 50 in group b. The additional data were relevant for clinical management in 14 of 20 patients in group a, and in 3 of 45 in group b. Based on the results of this study, TEE is useful in association with other radiologic techniques in patients with paracardiac neoplasms. As an imaging technique, it may represent a reliable alternative to computed tomography whenever the latter is not feasible. 相似文献
12.
D Pavan G L Nicolosi C Lestuzzi P Marino C Burelli F Zardo R Collazzo S Pizzolitto N Delendi D Zanuttini 《Giornale italiano di cardiologia》1984,14(7):471-478
The purpose of this study was to assess the capability of two-dimensional echocardiography to identify left ventricular thrombi as compared to standard single plane cineventriculography in 284 patients, who underwent both procedures within 24 hours for diagnostic purposes. In order to obtain informations about the degree of thrombus organization and diagnostic accuracy of the echocardiographic technique, two-dimensional echocardiographic examinations were also performed in 31 thrombi from 16 autopsy specimens. In 249 cases the results were negative and in 14 cases positive by both techniques. Seven cases were positive by cineventriculography but negative by 2D-echocardiography. In seven cases the findings were equivocal by two-dimensional echocardiography; three of them were negative, two positive, and two equivocal by cineventriculography. In two cases the results were negative by two-dimensional echocardiography but equivocal by cineventriculography. Finally five cases were diagnosed to have a thrombus but two-dimensional echocardiography but not by cineventriculography. In two patients, positive by two-dimensional echocardiography, who were on anticoagulant therapy, follow-up studies showed the disappearance of left ventricular thrombi. In all of them the thrombi showed tissue characteristics similar to those of fresh thrombi examined in vitro. Two-dimensional echocardiography seems to be more reliable than cineventriculography for assessing the presence, extension, number, and morphology of left ventricular thrombi. In vitro studies suggest that two-dimensional echocardiography cannot visualize small thrombi, that fibrotic areas may simulate a thrombus and that in some cases under or overestimation is possible. 相似文献
13.
To investigate the risk factors for man-to-woman sexual transmission of the human immunodeficiency virus (HIV), we carried out a cross-sectional study of 368 women who were steady partners of HIV-infected men attending 16 Italian clinical centers. Information was collected from the medical records of the infected men and by direct interviews with the women. In a logistic regression analysis, the woman's awareness of her partner's seropositivity (odds ratio [OR], 0.2; 95% confidence interval [CI], 0.0 to 1.1), use of condoms (OR, 0.3; 95% CI, 0.1 to 1), and oral contraceptive use (OR, 0.5; 95% CI, 0.3 to 1.0) were negatively associated with transmission of the HIV infection. An increased risk was found in women having sexual intercourse more than twice a week (OR, 2.4; 95% CI, 1.2 to 4.9) and in women who had been sexually exposed to HIV for between 2 and 5 years (OR, 3.5; 95% CI, 1.8 to 6.7). The transmission rate was higher in couples who engaged in anal sex (OR, 2.8; 95% CI, 1.3 to 6.3); in women reporting vaginitis (OR, 4.9; 95% CI, 2.4 to 10.2) or genital warts (OR, 33.3; 95% CI, 4.5 to 244.1); and in those using intrauterine devices (OR, 3.1; 95% CI, 1.4 to 7.1). The risk for women was also associated with a CD4+ cell count lower than 400/mm3 in their partners. Knowledge of the HIV status of the partner led to increased condom use but did not induce a lower frequency of sexual intercourse or an avoidance of anal sex. 相似文献
14.
Sabrina Cattaruzza Pier Andrea Nicolosi Roberto Perris 《Connective tissue research》2013,54(3-4):225-229
Proteoglycans (PGs) as a whole, or when considering their GAG chains as single entities, are emerging as key regulators of tumor progression. Expectations on using them as putative prognostic markers and potential therapeutic targets are increasing coincidentally. Due to the multitude of biological roles that they may invest and the ample spectrum of cellular processes that they may control, we still need to learn better how they regulate phenomena such as intracellular signaling, proliferation, apoptosis, motility, and drug resistance. Depending on the type, their expression pattern, and the accessibility of their molecular ligands, PGs can either promote or inhibit tumorigenesis. The structural and functional diversity of PGs coupled with their ubiquitous abundance place them at the crossroads of many critical steps within the metastatic cascade. As this phenomenon is the pivotal factor for patient survivals, particular attention should be given to the understanding of how PGs govern metastasis formation. 相似文献
15.
Sonaglioni Andrea Nicolosi Gian Luigi Rigamonti Elisabetta Lombardo Michele 《The international journal of cardiovascular imaging》2021,37(6):1913-1925
The International Journal of Cardiovascular Imaging - Left atrial (LA) mechanics assessed by two-dimensional speckle tracking echocardiography (2D-STE) have not been extensively studied and clearly... 相似文献
16.
Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF. 相似文献
17.
De Mattia L Dametto E Brieda M Del Bianco F Nicolosi GL 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2012,14(8):1220; author reply 1220-1220; author reply 1221
18.
Primitive hematopoietic stem cells differentiate into committed progenitors that are thought to selectively express hematopoietic growth factor receptor(s), thereby acquiring hematopoietic growth factor responsiveness. To assess whether hematopoietic stem cells express hematopoietic growth factor receptors, the progenitor activity of bone marrow (BM) fractions, isolated by expression of receptors for macrophage/monocyte colony-stimulating factor (M-CSF), were examined. Recovery of day-12 spleen colony-forming units (CFU-S) is diminished in both M-CSF receptor-positive (M-CSFR+) and M-CSFR- fractions, indicating antibody inhibition of day-12 CFU-S. Incubation of BM cells with antibody without fractionation inhibits 50% to 60% of day-12 CFU- S. This inhibition is specific (control antibodies have no effect) and reversible by removal of bound antibody at low pH. Incubating BM cells with control or antireceptor antibody does not affect day-8 CFU-S, which are predominantly erythroid. Treating sublethally irradiated mice with antibody inhibits endogenous day-12 CFU-S. These results indicate that some early progenitors express M-CSFRs, and blocking M-CSFRs inhibits the ability of these progenitors to form colonies, possibly because of inactivation caused by prolonged receptor blockade. 相似文献
19.
Mimo R Sparacino L Nicolosi G D'Angelo G Dall'Aglio V Lestuzzi C Pavan D Cervesato E Zanuttini D 《Echocardiography (Mount Kisco, N.Y.)》1991,8(6):619-626
We reviewed transthoracic (TTE) and transesophageal (TEE) echocardiograms of 100 consecutive patients: 63 male, 37 female, mean age 50 years (range 16-83 years), 32 with neoplastic disease, 18 aortic disease, 28 mitral valve disease, and 22 with other diseases. Absence or presence of mitral regurgitation (defined as mild, moderate, or severe) was assessed. TEE showed mild mitral regurgitation in 26 patients where TTE was negative. The overall estimate of regurgitant lesion severity was concordant at TEE and TTE in 64% of cases. The overall estimate of regurgitant lesion severity was also greater by one grade in 1% of cases at TTE, and in 35% of cases at TEE. Maximal digitized jet areas were 3.60 +/- 6.35 cm 2 at TTE and 3.04 +/- 3.79 cm 2 at TEE (P = NS). Correlation was r = 0.69 (TEE = 0.41 TTE + 1.55; P less than 0.001). TEE yielded a higher prevalence of mitral regurgitation than TTE with a trend toward greater overall estimate of mitral regurgitation at the semi-quantitative analysis. TTE and TEE showed similar mean results at the quantitative assessment of maximal jet areas. However, a highly significant random variability was observed in quantifying mitral regurgitation at TEE. 相似文献
20.
胰岛素样生长因子Ⅰ与肝纤维化 总被引:1,自引:1,他引:1
胰岛素样生长因子I(IGF-I)是体内普遍存在的多肽,循环系统中IGF-I主要来源于肝脏.在垂体生长激素的调控下,IGF-I对多种细胞如成纤维细胞、成骨细胞、平滑肌细胞等的有丝分裂均有调节作用.目前观点认为肝星状细胞(HSC)活化后可分泌大量胶原纤维,是肝纤维化时细胞外基质的主要来源.实验表明 IGF-I能够促进体外培养HSC增殖、活化并抑制其凋亡.而体内研究发现,肝硬化患者血清IGF-I浓度显著下降,外源性小剂量IGF-I 注射能够改善肝功能,为肝纤维化的治疗提供了新的理念. 相似文献