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排序方式: 共有1027条查询结果,搜索用时 15 毫秒
61.
Squillaci E Fanucci E Sciuto F Masala S Sodani G Carlani M Simonetti G 《Digestive diseases and sciences》2003,48(3):449-458
The principal criterion for resectability of pancreatic carcinoma is the assessment of vascular involvement. In a prospective evaluation the ability of Spiral CT Angiography (CTA) to detect vascular involvement in 50 patients with pancreatic carcinoma, was proved; DSA was performed later in all patients. In 20 patients, without vascular involvement, a complete concordance was obtained. Of 30 patients with vascular involvement, there was complete concordance between CTA and angiography in 22 patients and discordance in 8 patients. CTA was superior in 2 cases with periadventitial infiltration and in 5 patients with splenoportal confluence thrombosis. DSA was superior in 1 case with infiltration of the superior mesenteric vein. After surgical evaluation, sensitivity of CTA and DSA was 97% and 77%, respectively, and the negative predictive values were 95% and 74%. As compared to DSA, CTA is more rapid and less invasive and can be considered the modality of choice for preoperative work-up of pancreatic neoplasm. 相似文献
62.
Gallo D Ferrandina G Giacomelli S Fruscella E Zannoni G Morazzoni P Riva A Bombardelli E Mancuso S Scambia G 《Cancer letters》2002,186(1):43-48
The aim of this study was to extend our previous observations on the soy modulation of biochemical parameters in 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumors, by simultaneously investigating the expression of estrogen receptor-alpha (ERalpha), estrogen receptor-beta (ERbeta), progesterone receptor (PR), apoptosis, neu, and markers of cell proliferation, such as proliferating cell nuclear antigen (PCNA) by immunohistochemistry. The percentage of ERalpha positive tumors was 65.8% in masses from control animals, and significantly dropped to 36.8% in tumors from soy treated rats (P=0.010). The percentage of ERbeta positive tumors was 70.3% in masses from control animals vs. 50.0% in tumors from soy exposed animals (P=0.066). Moreover, the percentage of cases which were both ERalpha and ERbeta positive was significantly lower (17.6%) in soy treated than in control animals (51.3%) (P=0.006). The percentage of PR positive tumors was 34.2% in control animals vs. 2.6% in tumors from soy treated rats (P=0.0006). There were no statistically significant differences in the percentage of tumors positively stained for neu, apoptosis, or PCNA, in control vs. soy treated rats. However, when analyzing the reciprocal correlation among the different biochemical parameters we showed that, in treated animals, the majority of ERalpha positive tumors (91.7%) were also PCNA positive (P=0.036). The median percentage of PCNA positivity was significantly higher in ERalpha positive than in ERalpha negative tumors (25 vs. 5%) (P=0.0031). Moreover, an association was found between PCNA and neu status since all neu positive tumors were also PCNA positive (P=0.011). 相似文献
63.
Casetta I Monetti VC Malagù S Paolino E Govoni V Fainardi E Tola MR Granieri E 《Neuroepidemiology》2002,21(5):251-254
OBJECTIVES: The etiology of epilepsy remains unknown in most cases. We sought to investigate the role of some pre-, peri- and postnatal factors in the etiology of idiopathic and cryptogenetic partial epilepsy. METHODS: We carried out a community-based case-control study using the incidence cohort of epileptic patients living in the district of Copparo, in the province of Ferrara, Italy. The study was performed in 55 cases and 165 controls. A standardized questionnaire was used to collect information in face-to-face interviews. RESULTS: Multivariate logistic regression analysis found that a personal history of febrile convulsions [odds ratio (OR) = 4.01, 95% confidence interval (CI) = 1.3-19.1] and a family history of seizures in first-degree relatives (OR = 4.5, 95% CI = 1.8-18.6) were independent risk factors for the condition under study. We failed to demonstrate an association between partial epilepsy and previously suggested perinatal risk factors. CONCLUSION: The findings of this study further support the hypothesis of a genetic propensity for seizures, which may be expressed early by the occurrence of febrile convulsions. 相似文献
64.
Cocchi R Degli Esposti E Ruffo P Buda S Valpiani G Sturani A;Pandora Study Group 《Journal of nephrology》2002,15(1):29-35
BACKGROUND: The aim of the Pandora project is to collect epidemiological information, check diagnostic and therapeutic pathways, and assess outcomes in a large hypertensive population. This report presents the results on patients enrolled in the study between 1997-1999. METHODS: Twenty-one general practitioners working in the Ravenna Local Health Service took part in the study. They were supplied with IBM compatible PCs and were trained to enter the patient's data (age, gender, familiarity for cardiovascular diseases, smoking, hospitalisations for cardiovascular disorders, diabetes, blood pressure, total cholesterolemia, creatininemia, antihypertensive therapy) on So.Ge.Pa. software. Cardiovascular risk factors were assessed according to the WHO - ISH joint committee recommendations. RESULTS: 2,608 treated hypertensive patients were enrolled, 65% of whom showed inadequate blood pressure control. The prevalence of inadequate BP control was higher in patients on multiple-drug antihypertensive therapy compared with those on monotherapy (71.9% vs. 47.9%), in older than in younger patients (70.7% vs. 56.1%) and in patients with three cardiovascular risk factors, or diabetes, or affected target organs, compared to those with two or less risk factors (72.4% vs. 63.3%), (p < 0.001 for all). 63.6% of patients were at risk for age, 36.6% for family history of cardiovascular diseases and 31.7% for severe hypercholesterolemia. CONCLUSIONS: BP control was inadequate in a large percentage of patients, but it was particularly unsatisfactory in the elderly and in patients with high cardiovascular risk. A cluster of cardiovascular risk factors was found in both adequately and inadequately controlled hypertensive patients. 相似文献
65.
Epithelial abnormalities in cystic ovarian endometriosis. 总被引:6,自引:0,他引:6
Federico Prefumo Federica Todeschini Ezio Fulcheri Pier Luigi Venturini 《Gynecologic oncology》2002,84(2):280-284
OBJECTIVE: To evaluate the prevalence of epithelial abnormalities in cystic ovarian endometriosis. METHODS: In this observational study, the specimens of 388 consecutive patients undergoing a surgical procedure whose final diagnosis included cystic ovarian endometriosis were histopathologically reviewed. The prevalence and patient characteristics of cases featuring epithelial metaplasia, hyperplasia, atypia, and endometrioid carcinoma arising in endometriosis were analyzed. RESULTS: The epithelial lining was evaluable in 339 cases. Left-sided cysts were significantly more common than right-sided ones (P < 0.0001). The observed prevalence was 12.1% for metaplasia, 9.4% for hyperplasia, 5.9% for atypia, and 4.1% for endometrioid carcinoma arising in endometriosis. Complex hyperplasia, but not simple hyperplasia or metaplasia, was significantly more common in cases with associated endometrioid carcinoma than in all other cases (P < 0.00001). A statistically significant trend for increasing age from normal epithelium to carcinoma was observed (P < 0.001). CONCLUSIONS: Epithelial abnormalities are a common finding in cystic ovarian endometriosis. Despite their clinical significance being still debated, complex hyperplasia and atypia can be associated with malignant transformation of endometriosis. Their observation in a surgical specimen, particularly in older patients, should indicate a careful examination of the entire lining of the cyst and a strict follow-up of the patient. 相似文献
66.
Giulia Taraboletti Gianluca Micheletti Monica Rieppi Maura Poli Michele Turatto Cosmo Rossi Patrizia Borsotti Paola Roccabianca Eugenio Scanziani Maria Ines Nicoletti Ezio Bombardelli Paolo Morazzoni Antonella Riva Raffaella Giavazzi 《Clinical cancer research》2002,8(4):1182-1188
PURPOSE: We previously reported that paclitaxel, a microtubule-stabilizing drug, inhibited angiogenesis, mainly by inhibiting endothelial cell motility (D. Belotti et al., Clin. Cancer Res., 2: 1843-1849, 1996). The aim of this study was to select a taxane with little cytotoxicity but with antimotility and hence antiangiogenic activity. EXPERIMENTAL DESIGN: Different taxanes, seco derivatives, and 14-beta-hydroxy-10-deacetyl baccatin III derivatives were tested for their effects on the proliferation and motility of human umbilical vein endothelial cells. The antiangiogenic and antineoplastic activities of the compound selected from this screening were further investigated in experimental models in vitro and in vivo. RESULTS: From the screening of different taxanes, we selected IDN 5390, a seco derivative that showed potent antimotility activity and less cytotoxicity than paclitaxel. In comparable experimental conditions, IDN 5390 inhibited endothelial cell migration without affecting proliferation. This compound dose-dependently inhibited the capacity of human umbilical vein endothelial cells plated on Matrigel to organize into a network of cords. In vivo, IDN 5390 significantly inhibited fibroblast growth factor-2-induced angiogenesis in Matrigel implants. Daily treatment with IDN 5390 in mice bearing established lung micrometastases from the B16BL6 murine melanoma caused a reduction in the size of metastases. Finally, IDN 5390 slowed the s.c. growth of the paclitaxel-resistant human ovarian carcinoma, 1A9/PTX22, xenografted in nude mice. CONCLUSIONS: The seco derivative IDN 5390 might represent the prototype of a new class of taxane derivatives with antiangiogenic properties. 相似文献
67.
Giuliana Cassinelli Cinzia Lanzi Rosanna Supino Graziella Pratesi Valentina Zuco Diletta Laccabue Giuditta Cuccuru Ezio Bombardelli Franco Zunino 《Clinical cancer research》2002,8(8):2647-2654
Taxane-based therapies appear to have a significant efficacy in clinical trials on hormone-refractory prostate carcinoma. In the present study, we investigated the cellular response of androgen-independent prostate carcinoma cell lines to the novel taxane IDN 5109 (BAY 59-8862) and evaluated its antitumor activity. In previous preclinical studies, this new paclitaxel (PTX) analogue was characterized by high tolerability and antitumor efficacy, ability to overcome multidrug resistance, and activity by oral administration. Upon treatment, DU145 and PC3 prostate carcinoma cell lines underwent a transient mitotic arrest. This was followed by G1 arrest and rapid occurrence of apoptosis in DU145 cells, whereas in PC3 cells, which are defective for the postmitotic checkpoint, a slow cell death was preceded by DNA endoreduplication. At the biochemical level, such events were associated with tubulin polymerization, activation of the mitosis-promoting factor, and phosphorylation of Bcl-X(L)/Bcl-2/Raf-1. In addition, IDN 5109 shared with PTX the ability to down-regulate the expression of the two potent angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor. These findings indicated that IDN 5109 affected the same pathways involved in the cellular response to PTX and suggested that an antiangiogenic effect mediated by inhibition of paracrine stimulation of endothelial cells might contribute to the antitumor effect of both drugs. In in vivo experiments, the new taxane displayed a superior and more persistent effect compared with PTX against DU145 tumor xenografts. Such an effect was associated with pronounced reduction of the tumor microvessel density, superior to that achieved by PTX. These results support a potential therapeutic advantage of IDN 5109 over PTX against hormone-refractory prostate carcinoma. 相似文献
68.
Robin D. Wood Ezio Tirelli Kristyn J. Snyder Charles J. Heyser Tara M. LaRocca L. P. Spear 《Psychopharmacology》1998,138(2):114-123
While chronic intermittent administration of stimulants often induces behavioral sensitization in adulthood, stimulant sensitization
has rarely been reported prior to weaning [around postnatal day (P) 21]. Consistent pairing of drug administration with the
test context often facilitates sensitization in adults, yet young animals have been typically returned to the home cage immediately
post-injection. To determine whether promoting context-dependent sensitization might facilitate expression of sensitization
in preweanlings, Sprague-Dawley rats were injected daily from P14 to P20 with 0, 5, 15, or 30 mg/kg cocaine HC1 and placed
for 30 min in either the experimental chamber or home cage. On P21 (test day), subjects were challenged with either 15 mg/kg
cocaine or saline prior to placement in the experimental chamber. Significant sensitization of cocaine-induced stereotyped
head movements was evident in animals given 15 or 30 mg/kg chronically in the experimental chamber, but not when these same
doses were given in the home cage. Less consistent evidence for cocaine-induced sensitization was seen when examining locomotion,
although trends for sensitization of this behavior were seen in animals chronically injected in either the test chamber or
home cage. Thus, preweanlings can exhibit cocaine sensitization, particularly in terms of stereotypy, when tested shortly
after the chronic exposure period, with expression of this sensitization being facilitated by pairing the chronic injections
with the test context.
Received: 19 November 1996/Final version: 10 December 1997 相似文献
69.
Lamioni A Parisi F Isacchi G Giorda E Di Cesare S Landolfo A Cenci F Bottazzo GF Carsetti R 《Transplantation》2005,79(7):846-850
Extracorporeal photopheresis (ECP) may represent an alternative to immunosuppression, as a means of reducing rejection after thoracic organ transplantation. The mechanism by which ECP exerts its protective effects has, until now, remained elusive. We analyzed peripheral blood mononuclear cells of four children with chronic heart and lung transplant rejection, who received ECP in addition to conventional immunosuppressive treatment. The effects of ECP were evaluated at each cycle, comparing blood samples from the same patient collected before and after treatment. In vitro, peripheral blood mononuclear cells treated with ECP undergo apoptosis and are phagocytosed by immature dendritic cells, which, in turn, acquire a tolerogenic phenotype. The frequency of T cells, with a regulatory phenotype and strong suppressive activity, was significantly increased in the blood of ECP-treated patients. The immunomodulatory effects of ECP may be explained by its ability to increase the frequency of regulatory T cells with inhibitory action on transplant immune rejection. 相似文献
70.
Canine leishmaniasis, Italy 总被引:1,自引:0,他引:1
Ferroglio E Maroli M Gastaldo S Mignone W Rossi L 《Emerging infectious diseases》2005,11(10):1618-1620
We report the results of a survey to determine the prevalence of canine leishmaniasis and the presence of sand flies in northwestern Italy, where autochthonous foci of canine leishmaniasis have not been reported. Active foci of canine leishmaniasis were identified, which suggests that the disease is now also endemic in continental climate areas. 相似文献