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991.
CD2 physically associates with CD5 in rat T lymphocytes with the involvement of both extracellular and intracellular domains 总被引:1,自引:0,他引:1
Castro MA Tavares PA Almeida MS Nunes RJ Wright MD Mason D Moreira A Carmo AM 《European journal of immunology》2002,32(5):1509-1518
T lymphocytes can be activated and induced to proliferate through stimulation of the CD2 glycoprotein with functional combinations of CD2 antibodies. However, this mechanism of signal transduction via CD2 is still not fully understood. We have investigated which molecules on the T cell surface preferentially associate in Cis with CD2 and may regulate its signaling properties. Though a quantification method we found that CD5 represents the antigen capable of co-precipitating a larger proportion of CD2. Using co-capping assays and immunoprecipitations from cell lysates, we show that an association between CD2 and CD5 can be found in rat thymocytes, T lymphocytes and in a thymoma cell line. Possibly, this interaction is a direct one, since CD2 and CD5 transiently expressed in Cos7 cells co-precipitate each other. Furthermore, using CD2 chimeric proteins containing different domains of CD2, expressed in Cos7 cells as well as in stably transfected Jurkat cells, we show that the interaction between CD2 and CD5 is held at both the intra- and extracellular levels, but does not involve the transmembrane domain. The fact that both the extracellular and the cytoplasmic domains of CD2 interact with CD5 suggests a specific and tight association between the two molecules, possibly relevant for the fine-tuning of signal transduction in T lymphocytes. 相似文献
992.
Salamanca F 《Gaceta médica de México》2002,138(4):379-380
993.
Leptin and liver fibrosis: a matter of fat 总被引:11,自引:0,他引:11
Marra F 《Gastroenterology》2002,122(5):1529-1532
994.
OBJECTIVE: To propose and apply a protocol for assessing the outcome of surgery for carpal tunnel syndrome. METHODS: The protocol included a patient questionnaire that was self-administered before and 1 and 6 months after the operation to assess severity of symptoms (Boston questionnaire) and staging according to clinical (Giannini) and electrophysiological (Padua) severity scales. RESULTS: The results of a prospective series of 323 hands undergoing surgery for carpal tunnel syndrome by the mini-incision of the palm technique are reported. CONCLUSION: The method was found to be valid, precise, reliable, and straightforward, enabling a comparison of the results from different patient series and different operating techniques. 相似文献
995.
A new method for lower lip reconstruction is proposed. It is based on a double cutaneous and mucous V-Y advancement flap and is suggested for the surgical treatment of lip cancer confined between the skin and the vermilion with a horizontal spread. Sixteen patients were treated from 1996 to 2001 with this technique and the results were satisfactory both from the functional and the aesthetic standpoints. 相似文献
996.
Da Gama AD Nunes JS S DC Pedro LM Carmo GX Romero M 《Revista portuguesa de cirurgia cardio-toracica e vascular : orgao oficial da Sociedade Portuguesa de Cirurgia Cardio-Toracica e Vascular》2003,10(4):193-197
In this paper two patients with penetrating ulcers of the descending thoracic aorta are presented, a clinical condition recognized only recently, that may have a severe or even fatal outcome, due to rupture of the aorta. It is a peculiar form of the atherosclerotic disease, and its clinical and imagiologic presentation may mimics the classic aortic dissection of the distal type type. Computed tomography, nuclear magnetic resonance and transesophageal ecocardiography are the most apropriate methods for studying and diagnosis and the surgical management, aimed at the prevention or treatment of the aortic rupture, and based on the prosthetic aortic replacement, is the only alternative allowing the definite cure of the disease. The main features of pathology, clinical manifestations, diferential diagnosis and surgical management of this entity are described and discussed, according to the most recently articles published in the literature, on the subject. 相似文献
997.
Prifti E Bonacchi M Giunti G Frati G Leacche M Bartolozzi F 《Journal of cardiac surgery》2003,18(5):375-383
OBJECTIVE: The aim of this study is to evaluate in a cohort of patients with impaired left ventricular (LV) function and ischemic mitral valve regurgitation (MVR), the effects of on-pump/beating heart versus conventional surgery in terms of postoperative mortality and morbidity and LV function improvement. MATERIALS AND METHODS: Between January 1993 and February 2001, 91 patients with LVEF between 17% and 35% and chronic ischemic MVR (grade III-IV), underwent MV repair in concomitance with coronary artery bypass grafting (CABG) Sixty-one patients (Group I) underwent cardiac surgery with cardioplegic arrest, and 30 patients (Group II) underwent beating heart combined surgery. Aortic valve insufficiency was considered a contraindication for the on-pump/beating heart procedure. Mean age in Group I was 64.4 +/- 7 years and in Group II, 65 +/- 6 years (p = 0.69). RESULTS: The in-hospital mortality in Group I was 8 (13%) patients versus 2 (7%) patients in Group II (p > 0.1). The cardiopulmonary bypass (CPB) time was significantly higher in Group I (p < 0.001). In Groups I and II, respectively (p > 0.1), 2.5 +/- 1 and 2.7 +/- 0.8 grafts per patient were employed. Perioperative complications were identified in 37 (60.7%) patients in Group I versus 10 (33%) patients in Group II (p = 0.025). Prolonged inotropic support of greater than 24 hours was needed in 48 (78.7%) patients (Group I) versus 15 (50%) patients (Group II) (p = 0.008). Postoperative IABP and low cardiac output incidence were significantly higher in Group I, p = 0.03 and p = 0.027, respectively. Postoperative bleeding greater than 1000 mL was identified in 24 patients (39.4%) in Group I versus 5 (16.7%) in Group II (p = 0.033). Renal dysfunction incidence was 65.6% (40 patients) in Group I versus 36.7% (11 patients) in Group II (p = 0.013). The echocardiographic examination within six postoperative months revealed a significant improvement of MV regurgitation fraction, LV function, and reduced dimensions in both groups. The postoperative RF was significantly lower in Group II patients 12 +/- 6 (%) versus 16 +/- 5.6 (%) in Group I (p = 0.001). The 1, 2, and 3 years actuarial survival including all deaths was 91.3%, 84.2%, and 70% in Group I and 93.3%, 87.1%, and 75% in Group II (p = ns). NYHA FC improved significantly in all patients from both groups. CONCLUSION: We conclude that patients with impaired LV function and ischemic MVR may undergo combined surgery with acceptable mortality and morbidity. The on/pump beating heart MV repair simultaneous to CABG offers an acceptable postoperative outcome in selected patients. 相似文献
998.
Ferreira MA Nunes Odel R Leal LK Pessoa OD Lemos TL Viana GS 《Biological & pharmaceutical bulletin》2003,26(5):595-599
In previous studies in vitro we showed that the quinone fraction (QF) from the heartwood of Auxemma oncocalyx TAUB. presented antiplatelet and antioxidant activities. In the present work, the QF antioxidant property was evaluated in models of CCl(4)-induced hepatotoxicity in rats, and prolongation of pentobarbital-induced sleeping time in mice. Our results showed that levels of plasma glutamate-pyruvate-transaminase (GPT), as well as glutamate-oxalate-transaminase (GOT), were increased by the administration of CCl(4). On the other hand, only GPT levels were reduced by the QF treatment. Pentobarbital sleeping time was prolonged by the administration of CCl(4) and reduced by the QF treatment. Moreover, QF did not alter the pentobarbital-induced sleeping time. In conclusion, we showed that QF, represented mainly by oncocalyxone A, has hepatoprotective activity, and this effect is at least in part due to the antioxidant activity of this quinone. 相似文献
999.
Barbaro SP Petrigni G Giovannelli F Cerroni F Caroselli A De Rosa R Caroselli C 《European review for medical and pharmacological sciences》2003,7(6):171-173
BACKGROUND: To understand if relapse, following antimicrobial treatment was due to re-infection or to recrudescence. METHODS: Fifty patients with dyspepsia were studied prospectively. They were followed up by endoscopy and biopsy of antral mucosa before and after treatment with anti-microbial therapy. Gel isoelectrofocusing was used to characterize protein profile of Hp. RESULTS: At baseline 40 patients were affected by chronic gastritis associated with Hp. At the end of treatment 75% patients given omeprazole, amoxicillin and clarithromycin were Hp infected: 43% showed the same protein profile and 57% different. CONCLUSIONS: Our data suggest that the relapse is due to recrudescence or to reinfection. 相似文献
1000.
Ptychopetalum olacoides,a traditional Amazonian "nerve tonic", possesses anticholinesterase activity
Siqueira IR Fochesatto C da Silva AL Nunes DS Battastini AM Netto CA Elisabetsky E 《Pharmacology, biochemistry, and behavior》2003,75(3):645-650
The cholinergic hypothesis of Alzheimer disease (AD) has provided the rationale for the current pharmacotherapy of this disease, in an attempt to downgrade the cognitive decline caused by cholinergic deficits. Nevertheless, the search for potent and long-acting acetylcholinesterase (AChE) inhibitors that exert minimal side effects to AD patients is still an ongoing effort. Amazonian communities use traditional remedies prepared with Ptychopetalum olacoides (PO, Olacaceae) roots for treating various central nervous system conditions, including those associated with aging. The fact that PO ethanol extract (POEE) has been found to facilitate memory retrieval in the step down procedure in young and aged mice prompt us to evaluate its effects on AChE activity in memory relevant brain areas. POEE significantly inhibited AChE activity in vitro in a dose- and time-dependent manner in rat frontal cortex, hippocampus and striatum; a significant inhibition was also found in these same brain areas of aged (14 months) mice after acute administration of POEE (100 mg/kg ip). We propose that such AChE inhibitory activity is a neurochemical correlate of a number of therapeutic properties traditionally claimed for P. olacoides, particularly those associated with cognition. 相似文献