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61.
62.
Solange Cailleaux Rodrigo A. B. Lopes-Martins Flávio Aimbire Renato S. B. Cordeiro E. Tibiriçá 《Naunyn-Schmiedeberg's archives of pharmacology》1999,359(6):505-511
The hypothesis that platelet-activating factor (PAF) plays a role in the modulation of the vasomotor tone and blood pressure
was put forward by our group in previous in vivo studies in anaesthetised rabbits. The present study was undertaken to investigate
the putative role of this lipid mediator in the vascular reactivity of the renal circulation, using the experimental model
of the isolated perfused rabbit kidney. Dose-response curves to noradrenaline-induced vasoconstriction were performed before
and after continuous infusions of two different PAF-receptor antagonists (WEB 2086 and yangambin) and of the phospholipase
A2 inhibitor mepacrine. The increases in renal perfusion pressure elicited by noradrenaline were potentiated by all the above-mentioned
treatments in a dose-dependent manner. Moreover, prostaglandin F2α-induced vasoconstriction was also potentiated by the administration of the PAF receptor antagonists and mepacrine. Furthermore,
the administration of PAF into the renal circulation induced dose-related and long-lasting vasodilator responses, which were
blocked by the PAF receptor antagonists. Nevertheless, PAF-induced renal vasodilation was also abolished by a pretreatment
with mepacrine or with the cyclooxygenase inhibitor indomethacin, suggesting that it enhances the secondary formation of vasodilator
arachidonic acid metabolites. The data indicate that PAF is involved in the modulation of the vasomotor tone in the renal
circulation, through the release of cyclooxygenase products, constituting an additional mechanism of modulation of smooth
muscle cell contractility to the ones exerted by well-known vasoactive substances of endothelial origin such as nitric oxide.
Received: 20 April 1998 / Accepted: 5 March 1999 相似文献
63.
Maria A. Annunziata Ph.D. Carlo Rossi M.D. Renato Talamini Sc.D. Salvatore Tumolo M.D. Silvio Monfardini M.D. 《Supportive care in cancer》1996,4(5):334-340
The aim of this study was to determine the influence of socio-demographic and professional factors on physicians' attitudes to the terminally ill. Between May 1992 and May 1993, a survey was conducted in the province of Pordenone (north-east, Italy) in order to analyse a number of specific issues, such as emotional involvement, the need for aggressive treatments and the communication of diagnosis and prognosis. After obtaining a list of board-certified physicians from the Medical Association office in Pordenone, a modification of the cancer questionnaire of Haley and Blanchard (QSPT) was mailed to 916 doctors. Of these, 605 (60%; 487 male, 118 female; mean age 41 ± 11 SD) returned the completed questionnaire. Within the group of responders, we identified three main subgroups, according to their type of activity: general practitioners (175, 29%), hospital doctors (235, 39%) and other doctors (195, 32%). In age, sex and activity, the only significant difference between responders and non-responders was age (mean age 41 and 43 years respeetively). Most of the responders (77%) stated that they were able to deal with the terminally ill patient and his/her needs; 44%, however, admitted that patients' anxiety is sometimes unbearable. For the vast majority of the doctors polled (91%), providing a comfortable environment for an incurable patient was more important than pursuing aggressive treatment, but only 44% were convinced of the uselessness of aggressive care. To the question on whether to disclose information about imminent death to allow patients to prepare spiritually, 37% answered No, 38% Yes, and 25% were uncertain. Almost all responders (95%), however, believed in the beneficial effect of hope on the terminally ill. Ourresults suggest that doctors' professional and, most of all, sociodemographic and cultural factors determine the relationship with the patient on both the emotional and the clinical decision-making levels. 相似文献
64.
65.
Diego Serraino Silvia Franceschi Renato Talamini Sergio Frustaci Carlo La Vecchia 《Cancer causes & control : CCC》1991,2(3):157-164
The role of socioeconomic and anthropometric indicators, tobacco, alcohol consumption, dietary habits, and medical history in the etiology of soft-tissue sarcoma (STS) was examined in a hospital-based case-control study, conducted in the Friuli-Venezia Giulia region of northeast Italy, between 1985 and 1990. A total of 88 STS cases (53 males and 35 females; median age: 52 years) and of 610 controls (306 males and 304 females; median age: 54 years) were interviewed. There were significant excess risks associated with a history of herpes zoster infection (odds ratio [OR]=2.4,95 percent confidence interval [CI]=1.1–5.3), chicken pox (OR=2.2, CI=1.2–4.3) and mumps in childhood (OR=2.0, CI=1.1–3.9). History of diabetes was also linked to a nonsignificant increase in STS risk (OR=1.8, CI=0.6–5.4), whereas exposure to radiation for diagnostic or therapeutic purposes was not related to the probability of developing STS. None of the investigated socioeconomic and anthropometric indicators seemed to affect STS risk; neither did tobacco smoking, nor consumption of alcohol, coffee, and tea beverages. Conversely, among the dietary habits investigated, a significant positive association emerged with an increasing frequency of consumption of dairy products (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiiYdd9qrFfea0dXdf9vqai-hEir8Ve% ea0de9qq-hbrpepeea0db9q8as0-LqLs-Jirpepeea0-as0Fb9pgea% 0lrP0xe9Fve9Fve9qapdbaqaaeGacaGaaiaabeqaamaabaabcaGcba% Gaae4XdmaaCaaaleqabaGaaGOmaaaaaaa!3DA2!\[{\rm{\chi }}^2\]for trend=6.8, P<0.01) and oil (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiiYdd9qrFfea0dXdf9vqai-hEir8Ve% ea0de9qq-hbrpepeea0db9q8as0-LqLs-Jirpepeea0-as0Fb9pgea% 0lrP0xe9Fve9Fve9qapdbaqaaeGacaGaaiaabeqaamaabaabcaGcba% Gaae4XdmaaCaaaleqabaGaaGOmaaaaaaa!3DA2!\[{\rm{\chi }}^2\]for trend=4.3, P<0.05), while a negative association was seen for intake of whole grain bread and pasta (OR for highest cf lowest tertile=0.4, CI=0.2–0.9).Support for this project was contributed by the Italian Association for Cancer Research, Milan, and the Italian National Research Council (CNR Applied Project Oncology, Contract 87.01544.44). 相似文献
66.
Pietra N Sarli L Maccarini PU Sabadini G Costi R Gobbi S 《World journal of surgery》2000,24(3):345-352
Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in
patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest
in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this
audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography
(IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy
(LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy,
or a risk of contrast-associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based
on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic
retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast-associated
acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out
in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup
permitted the sequential endoscopic-laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow-up
period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population
to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem
helpful in reducing the incidence of CBD injuries during LC. 相似文献
67.
Marina Kartachova Rick L M Haas Renato A Valdés Olmos Frank J P Hoebers Nico van Zandwijk Marcel Verheij 《Radiotherapy and oncology》2004,72(3):333-339
BACKGROUND AND PURPOSE: Anticancer therapy induces apoptosis in a dose- and time-dependent fashion. (99m)Tc-Hynic-rh-Annexin V scintigraphy (TAVS) enables non-invasive in vivo imaging of treatment-induced apoptosis. We identified the visual patterns of (99m)Tc-Hynic-rh-Annexin V tumour uptake and related these to treatment response. PATIENTS AND METHODS: Thirty-three patients with malignant lymphoma (n=26), leukaemia (n=1) NSCLC (n=5), H&NSCC (n=1), scheduled for radiotherapy (n=27), platinum-based chemotherapy (n=5) or concurrent chemoradiation (n=1), underwent TAVS before and early after the start of treatment. Planar and SPECT images were visually examined to assess changes in tumour (99m)Tc-Hynic-rh-Annexin V uptake. Twenty-nine patients were eligible for further analysis. Annexin V uptake before (U(baseline)) and early after (U(post)) the start of treatment was graded using a four-step scale: 0, absent; 1, weak; 2, moderate and 3, intense. The difference between these values (Delta U) was calculated and correlated to tumour response after therapy (Spearman rank correlation test). RESULTS: Weak to moderate U(baseline) was detected in 13/15 patients with a complete response and U(post) was markedly increased in all these cases (Delta U range 1-3). Partial response (n=7) was associated with weak to moderate U(baseline) and a moderately increased U(post) (Delta U range 1-2). In patients with stable disease (n=5), U(baseline) was predominantly weak, without considerable changes in uptake after the start of treatment (Delta U range 0-1). Finally, in case of progressive disease (n=2), either no tumour uptake or a decrease in U(post) was detected (Delta U=-1). A statistically significant correlation was found between changes in (99m)Tc-Hynic-rh-Annexin V tumour uptake and clinical response (correlation coefficient=0.62; P<0.001). CONCLUSIONS: Complete or partial tumour response was associated with a marked increase of (99m)Tc Hynic-rh-Annexin V accumulation early during treatment compared to baseline values. In case of stable or progressive disease, pretreatment scans demonstrated predominantly low (99m)Tc Hynic-rh-Annexin V tumour uptake and no significant increase early after treatment. These results indicate that TAVS might be useful as a predictive test for treatment response. 相似文献
68.
G Bacci A Briccoli M Rocca S Ferrari D Donati A Longhi F Bertoni P Bacchini S Giacomini C Forni M Manfrini S Galletti 《Annals of oncology》2003,14(7):1126-1134
BACKGROUND: Effective adjuvant or neoadjuvant regimens of chemotherapy have dramatically improved the prognosis of patients with high-grade osteosarcoma of the extremity, localized at diagnosis. Currently, little is known about patients with metastatic disease at presentation. PATIENTS AND METHODS: From May 1995 to May 2000, 57 patients with osteosarcoma of the extremity, metastatic at presentation, were treated according to the following scheme: primary chemotherapy, restaging, simultaneous resection of primary tumor and metastatic lesions, and maintenance chemotherapy. RESULTS: Thirty-five patients achieved remission. At a follow-up ranging from 2 to 7 years, seven remained continuously free of disease, one died of chemotherapy-related toxicity and 27 patients relapsed. Twenty-one of the 22 patients who never achieved remission died as a result of the tumor, as well as 20 of the 27 who achieved remission but then relapsed. Of the remaining seven relapsing patients, six are alive with uncontrolled disease, while one is alive and free of disease 24 months after the last post-relapse treatment. Two-year event-free survival (EFS) and overall survival (OS) were 21% and 55%, respectively. These results are significantly poorer than those achieved in 128 contemporary patients with non-metastatic disease at presentation, treated with the same chemotherapy protocol (2-year EFS and OS of 75% and 94%, respectively). CONCLUSIONS: The results of our study confirm that the prognosis of patients with osteosarcoma of the extremity, metastatic at presentation, remains poor, despite the use of aggressive treatments. 相似文献
69.
Guglielmo Nasti Renato Talamini Andrea Antinori Ferdinando Martellotta Gaia Jacchetti Francesco Chiodo Giuseppe Ballardini Laura Stoppini Giovanni Di Perri Maurizio Mena Marcello Tavio Emanuela Vaccher Antonella D'Arminio Monforte Umberto Tirelli 《Journal of clinical oncology》2003,21(15):2876-2882
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1). 相似文献
70.
Renato Roithmann Jerry Chapnik Philip Cole John Szalai Noe Zamel 《The Laryngoscope》1998,108(5):712-715
The aim of this study is to evaluate the effect of an external nasal dilator in patients with nasal obstruction secondary to mucosal congestion (n = 33) or to septal deviation in the nasal valve area (n = 28). A group of subjects with healthy nasal cavities was tested also (n = 51). Acoustic rhinometric and rhinomanometric nasal measurements were performed with and without the dilator and before and after topical decongestion of the nasal mucosa. A visual analog scale was employed to evaluate the subjective sensation of nasal obstruction. Objective measurements showed that the external dilator increased the minimum cross-sectional area and decreased the nasal resistance significantly in all three groups (P < 0.01). The effect was more impressive in patients with septal deviation (P < 0.001). Subjective assessments reflected patency in all subjects except those in the mucosal swelling group (P = 0.06). From this study the authors conclude that the external nasal dilator offers an effective, nonsurgical therapeutic approach in the management of septal deviation that obstructs the nasal valve area. Although patients with nasal obstruction secondary to mucosal congestion showed objective improvement with the nasal dilator, these changes were not accompanied by a sensation of enhanced patency. 相似文献