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41.
42.
Crusco F Antoniella A Papa V Menzano R Di Lazzaro D Di Manici G Ragni T Giovagnoni A 《La Radiologia medica》2007,112(4):538-549
PURPOSE: The study was undertaken to evaluate the 3-year outcome of patients undergoing coronary artery bypass grafting (CABG) involving the use of the radial artery (RA) in comparison with the left internal mammary artery (LIMA) and saphenous vein (SV) grafts by using 16-slice multidetector computed tomography (MDCT). MATERIALS AND METHODS: Fifty-one patients underwent electrocardiogram (ECG)-gated 16-MDCT 32+/-4 months after surgery. A total of 50 LIMA grafts, 55 SV grafts and 51 RA grafts were studied. Approximately 68.6% or RAs were free, 21.5% sequential and 9.8% composite. Grade 0 was defined as complete patency, grade 1 as focal stenosis (>70%) and grade 2 as graft occlusion. The Fisher exact test was used to analyse variables (p<0.05 significant). Concordance between readers for the detection of patency was calculated by the kappa-value. RESULTS: LIMA had the best patency rate (94.0%), followed by SV (83.6%) and RA (74.5%). Regarding RA, the patency rate by territory was 79.4% in the left circumflex coronary artery (LCX), 72.7% in the left anterior descending (LAD) and 50% in the right coronary artery (RCA); the occlusion rate was 20.0% among free grafts, 18.2% among sequential grafts and 20.0% among composite grafts. The kappa-value was 0.86. CONCLUSIONS: Sixteen-slice MDCT scanners enable accurate analysis of CABG status and are a useful noninvasive diagnostic tool for midterm clinical follow-up of patients who have undergone CABG involving the use of RA. 相似文献
43.
Tiziana A. L. Brevini Georgia Pennarossa Stefania Antonini Alessio Paffoni Gianluca Tettamanti Tiziana Montemurro Enrico Radaelli Lorenza Lazzari Paolo Rebulla Eugenio Scanziani Magda de Eguileor Nissim Benvenisty Guido Ragni Fulvio Gandolfi 《Stem cell reviews》2009,5(4):340-352
Human parthenogenetic embryos have recently been proposed as an alternative, less controversial source of embryonic stem cell (ESC) lines; however many aspects related to the biology of parthenogenetic embryos and parthenogenetic derived cell lines still need to be elucidated. We present here results on human cell lines (HP1 and HP3) derived from blastocysts obtained by oocyte parthenogenetic activation. Cell lines showed typical ESC morphology, expressed Oct-4, Nanog, Sox-2, Rex-1, alkaline phosphatase, SSEA-4, TRA 1-81 and had high telomerase activity. Expression of genes specific for different embryonic germ layers was detected from HP cells differentiated upon embryoid body (EBs) formation. Furthermore, when cultured in appropriate conditions, HP cell lines were able to differentiate into mature cell types of the neural and hematopoietic lineages. However, the injection of undifferentiated HP cells in immunodeficient mice resulted either in poor differentiation or in tumour formation with the morphological characteristics of myofibrosarcomas. Further analysis of HP cells indicated aberrant levels of molecules related to spindle formation as well as the presence of an abnormal number of centrioles and autophagic activity. Our results confirm and extend the notion that human parthenogenetic stem cells can be derived and can differentiate in mature cell types, but also highlight the possibility that, alteration of the proliferation mechanisms may occur in these cells, suggesting great caution if a therapeutic use of this kind of stem cells is considered. 相似文献
44.
Ferrero S Esposito F Biamonti M Bentivoglio G Ragni N 《Expert Review of Neurotherapeutics》2008,8(6):979-988
Myasthenia gravis (MG) affects women in the second and third decades of life, overlapping with the childbearing years. During pregnancy, the course of this disease is unpredictable; worsening of symptoms occurs more likely during the first half of pregnancy and postpartum. MG can be well managed during pregnancy with relatively safe and effective therapies. Cesarean section is recommended only for obstetric reasons; epidural anesthesia is advised to reduce physical and emotional stress. Anticholinesterase drugs are the mainstay of treatment, when MG symptoms are not satisfactorily controlled, corticosteroids, azathioprine and in some cases cyclosporin A may be used. Life-threatening conditions (e.g., respiratory insufficiency) may occur during pregnancy; therefore, intensive check-ups by a gynecologist and a neurologist are necessary. 相似文献
45.
Response of bone marrow stroma cells to demineralized cortical bone matrix in experimental spinal fusion in rabbits 总被引:3,自引:0,他引:3
The effect of autogeneic bone marrow (BM) cells and allogeneic demineralized bone matrix (DBM), alone or combined, as transplantation materials was studied in an experimental posterior thoracic spinal fusion model in rabbits. Transplantation of composite grafts composed of BM and DBM showed the first signs of fusion between two spinal segments after four weeks, reaching 86% after 20 weeks. Late fusion results achieved with DBM alone were similar. The capacity of BM per se to build up a spinal fusion was insignificant. Calcified tissue, documented roentgenographically, was shown to develop locally with time, and the earliest bridging of an interspace was noted after four weeks. Histologically, formation of new bone and cartilage was observed after two weeks, showing mature lamellar bone formation between thoracic segments after 20 weeks. Furthermore, increased 45Ca activity was still observed in the fused tissues after 20 weeks. Although, with grafting materials used, this model for experimental spinal fusion gave promising results, further investigations with other fusion techniques could give still better effects. 相似文献
46.
Ferrero S Pretta S Ragni N 《European journal of obstetrics, gynecology, and reproductive biology》2004,115(1):3-9
Care of pregnant women with multiple sclerosis (MS) is challenging because of the multiple physiological changes associated with pregnancy and the need to consider the impact of any intervention on the foetus. Pregnancy is associated with clinical MS stability or improvement, while the rate of relapse rises significantly during the first three months post-partum before coming back to its level prior to pregnancy. Gestational history has no influence on long-term disability and MS does not seem to influence pregnancy or the child's health. Apart from methotrexate and cyclophosphamide, most drugs used regularly to treat MS can safely be used by pregnant women. Intravenous steroids may be used with relative safety during pregnancy. Maternal use of azathioprine is not associated with an increased risk of congenital malformations, though impaired foetal immunity, intrauterine growth retardation and prematurity are occasionally observed. Cyclosporin is not teratogenic, but may be associated with growth retardation and prematurity. Pregnancy should be avoided in women treated with methotrexate because of its known abortifacient effects and risk of causing typical malformations. Cyclophosphamide is teratogenic in animals, but population studies have not conclusively demonstrated its teratogenicity in humans. Until information is available regarding safety, glatiramer acetate, mitoxantrone, interferon-beta-1a and interferon-beta-1b should be discontinued before an anticipated pregnancy. Women with MS are no more likely to experience delivery complications than are women without MS and the mode of delivery should be decided strictly on obstetrical criteria. Spinal, epidural and general anaesthesia can all be used safely in MS patients. Young women with MS who desire children can be reassured that their infants are not at increased risk of malformations, preterm delivery, low birth weight, or infant death. The progressive nature of the disease may motivate affected women to start or complete their families as soon as possible. 相似文献
47.
Infection with human immunodeficiency virus and vulnerability to psychiatric distress. A study of men with hemophilia 总被引:1,自引:0,他引:1
We examined psychiatric correlates of human immunodeficiency virus (HIV) infection in a major risk group for acquired immunodeficiency syndrome, men with hemophilia. A central goal was to identify psychosocial factors associated with increased vulnerability to psychiatric distress after infection with HIV. Seventy-five hemophiliacs, 31 of whom were HIV seropositive (HIV+), were studied. The HIV+ men had elevated depression, anxiety, and anger-hostility symptom scores relative to those of men who were seronegative for HIV. There were no additional symptom differences among men according to infection stage or clinical severity of hemophilia. Men with any of eight psychosocial characteristics were particularly susceptible to effects of infection on mental health: a personal history of psychiatric distress before HIV diagnosis; familial psychiatric history; a high school education or less; low social support from one's wife; low family support; low friend support; a poor sense of mastery over one's life; and experiencing recent life events involving loss. The HIV+ men with one or more such characteristics were highly symptomatic; remaining HIV+ men had significantly lower symptom levels, similar to the low levels noted in the men seronegative for HIV. The findings provide initial empiric support for the notion that clinical services to alleviate emotional distress should be targeted to intervene on HIV+ persons' psychosocial assets and liabilities. 相似文献
48.
C-reactive protein induces tissue factor expression and promotes smooth muscle and endothelial cell proliferation 总被引:6,自引:0,他引:6
49.
Acquired immunodeficiency syndrome-associated non-Hodgkin's lymphomas and other malignancies in patients with hemophilia 总被引:3,自引:0,他引:3
Ragni MV; Belle SH; Jaffe RA; Duerstein SL; Bass DC; McMillan CW; Lovrien EW; Aledort LM; Kisker CT; Stabler SP 《Blood》1993,81(7):1889-1897
Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men. 相似文献
50.