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21.
Pleural mesotheliomas are rare, and their diagnosis and treatment not clear. The case observed in our Department leads us to an analysis of the literature. This showed that differential diagnosis with pulmonary carcinoma is very difficult, even in cases of parietal mesothelioma; however local treatment may be performed even in malignant mesothelioma.  相似文献   
22.
OBJECTIVES: The sinuses of Valsalva are known to contribute to the normal function of the aortic valve. Little is known about their role in promoting coronary artery blood flow. The aim of this study was to compare coronary artery flow characteristics among patients undergoing a Bentall operation by means of a conventional cylindrical Dacron conduit or with a new conduit with pseudosinuses of Valsalva or in patients retaining their natural sinuses of Valsalva after aortic valve and supracoronary ascending aorta replacement. METHODS: One year after a Bentall procedure with a standard cylindrical Dacron conduit (7 patients, group A) or with the new conduit (7 patients, group B), or after aortic valve and ascending aortic replacement (control group, 7 patients, group C) coronary flow velocity reserve and diastolic to systolic time integral ratio at baseline and after maximal hyperemia (with 40 microg of adenosine) were assessed by using a 0.014-in. Doppler guidewire positioned in the middle portion of the left anterior descending coronary artery. All patients were in NYHA class I, sinus rhythm and free of coronary disease. RESULTS: Arterial blood pressures and heart rate were comparable among groups. Intracoronary Doppler measurements did not show any significant difference in coronary vascular reserve between the three groups (3.6+/-0.4 vs 3.1+/-0.7 vs 3.7+/-0.5, P = 0.2). A greater diastolic component at baseline was present in group B patients (5.5+/-1.9 vs 3.5+/-0.9 in group A and 3.7+/-0.9 in group C, P = 0.024). After maximal hyperemia the diastolic component increased slightly in group A patients (8%) while both in groups B and C significantly decreased (-15 and -20%, respectively) (P = 0.017). CONCLUSIONS: The presence of pseudosinuses of Valsalva does not influence coronary flow reserve. After maximal coronary vasodilation the increase in the systolic component of coronary flow is more evident in the presence of sinuses or pseudosinuses of Valsalva, thus suggesting that coronary flow pattern may be affected by the presence of sinuses.  相似文献   
23.
The aim of this study was to evaluate the occurrence of deep venous thrombosis (DVT) and superficial vein thrombosis (SVT) and its prophylaxis with an oral anti-edema and antithrombotic agent (Pycnogenol, Horphag, Research Management SA, Geneva, Switzerland) in long-haul flights, in subjects at moderate to high-risk of DVT and SVT. The study pre-included 244 pre-selected subjects; 211 were included (33 were excluded for several reasons due to logistic problems) and 198 completed the study; 13 subjects were lost for follow-up at the end of the flight, all for non-medical problems (i.e., for difficult connections). All subjects were scanned within 90 minutes before the flight and within 2 hours after disembarking. Subjects were supplemented with 100 mg Pycnogenol per capsule. Treatment subjects received two capsules between 2 and 3 hours before flights with 250 mL of water; two capsules were taken 6 hours later with 250 mL of water and one capsule the next day. The control group received comparable placebo at the same intervals. The flight duration was on average 8 hours and 15 minutes (SD 55 min) (range, 7.45-12.33). In the control group there were five thrombotic events (one DVT and four superficial thromboses) while only nonthrombotic, localized phlebitis was observed in the Pycnogenol group (5.15% vs. no events; p<0.025). The ITT (intention to treat) analysis detects 13 failures in the control group (eight lost to follow up + five thrombotic events) of 105 subjects (12.4%) vs. five failures (4.7%; all lost, no thrombotic events) in the treatment group (p<0.025). No unwanted effects were observed. In conclusion, this study indicates that Pycnogenol treatment was effective in decreasing the number of thrombotic events (DVT and SVT) in moderate-to-high risk subjects, during long-haul flights.  相似文献   
24.
With improvements in the safety of Whipple resection in recent decades, surgeons have continued to explore the role of more extensive lymphadenectomy in hope of improving long-term survival. A systematic literature search of level I evidence addressing the role of the extent of lymphadenectomy was undertaken. Only reports of prospective, randomized controlled trials comparing pancreaticoduodenectomy with standard lymphadenectomy to pancreaticoduodenectomy with extended lymphadenectomy where information regarding survival, morbidity, mortality, the number of resected lymph nodes in each group and detailed operative technique were included. Four prospective, randomized trials comprising some 424 patients and one meta-analysis were identified. In aggregate, these studies confirmed that the number of resected lymph nodes was significantly higher in the pancreaticoduodenectomy with extended lymphadenectomy group. Morbidity and mortality rates were comparable. Postoperative diarrhea in the early months after operation was problematic in patients undergoing extended lymphadenectomy. In none of the studies was a benefit in long-term survival demonstrated. Standard pancreaticoduodenectomy continues to be the operation of choice for adenocarcinoma of the head of the pancreas. Presented at The Society for Surgery of the Alimentary Tract Postgraduate Course “Systematic Reviews of Pancreaticobiliary Disease Customized for the Gastroenterologist and Gastrointestinal Surgeon” on May 20, 2007, Washington, D.C.  相似文献   
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26.
BACKGROUND: Risperidone has been shown to be clinically effective for the treatment of aggressive behavior in children, yet no information is available regarding whether risperidone exhibits aggression-specific suppression in preclinical studies that use validated developmentally immature animal models of escalated aggression. Previously, we have shown that exposure to low doses of the psychostimulant cocaine-hydrochloride (.5 mg/kg intraperitoneally) during the majority of pubertal development (postnatal days [P]27-57) generates animals that exhibit a high level of offensive aggression. This study examined whether risperidone exerts selective aggression-suppressing effects by using this pharmacologic animal model of highly escalated offensive aggression. METHODS: Experimental hamsters were tested for offensive aggression after the acute administration of risperidone (.05-1.0 mg/kg, intraperitoneally). RESULTS: Risperidone dose-dependently reduced the highly aggressive phenotype, with a significant reduction observed at .1-.2 mg/kg for most aggressive responses measured. Experimental animals treated with higher doses of risperidone (.3-1.0 mg/kg) showed significant reductions in aggression and social interest toward intruders, indicating more general behavioral inhibition. CONCLUSIONS: These studies provide evidence that risperidone exerts specific aggression-suppressing effects in a developmentally immature animal model of escalated aggression.  相似文献   
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28.
Epitope Context and Reshaping of Activated T Helper Cell Repertoire   总被引:1,自引:0,他引:1  
In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells.  相似文献   
29.
Summary Human fibrin glue (Tissucol) is a plasma-derived compound endowed with adhesive and hemostatic properties and possessing a specific local anti-infection function mediated through activation of nonspecific immunity elements. The aim of this study is to show that in patients who have undergone prolonged reconstructive plastic surgery following cancer resection, Tissucol decreases infectious complications as compared to a control group. Between June 1985 and February 1988, 51 subjects were treated with fibrin glue during reconstruction operations. Analysis of the results showed that Tissucol produced a statistically significant reduction both of immediate complications, such as inflammation and partial separation of the surgical wound, and of delayed complications, such as scar hypertrophy and cutaneous fistulae. In conclusion, patients treated with Tissucol showed a better quality of surgical wound, a more rapid postoperative functional recovery and consequently a decrease in the duration of hospitalization.  相似文献   
30.
The aim of the present work was to evaluate whether low day 3 luteinizing hormone (LH) values in the presence of normal follicle stimulating hormone (FSH) are predictive of poor response to ovarian stimulation. Two groups of women undergoing ovarian stimulation and differing only in the day 3 LH concentration (<3 mIU/ml, study group, n=30; >3 mIU/ml, control group, n=45) were retrospectively analysed. Study group patients developed a lower oestradiol peak (703+/-388 versus 955+/-400 ng/ml; P = 0.005) and a lower number of follicles >15 mm diameter at the time of human chorionic gonadotrophin (HCG) administration (2.6+/-1.3 versus 3.6+/-1.8; P=0.004) than the control group. Conversely, a similar ratio of oestradiol: follicles >15 mm diameter was observed (256+/-118 versus 269+/-93; P=0.563). The number of follicles >10 mm at the time of HCG administration appeared to be lower in the study group, but this difference was not statistically significant (6+/-3.9 versus 7.8+/-4.3). Our data indicate that day 3 LH values <3 mIU/ml are predictive of poor response to ovarian stimulation.   相似文献   
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