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51.
Giordano Stabellini Chiara Balducci Cinzia Lilli Lorella Marinucci Ennio Becchetti Francesco Carinci Carla Calastrini Claudia Dolci Eleonora Lumare Paola Locci 《Biomedicine & Pharmacotherapy》2008,62(7):436-442
Tissue infiltration is different in desmoid and fibroma tumours. Both produce high levels of transforming growth factor beta1 (TGFbeta1), which is related to extracellular matrix (ECM) accumulation which in turn regulates cell function and cell migration. Interactions between collagen, proteoglycans and cell surface fibronectin are involved in the assembly and functions of the ECM. As toremifene inhibits collagen and TGFbeta1 synthesis, we tested it in normal, desmoid and fibroma fibroblasts. We will report the changes in glycosaminoglycan (GAG) and collagen synthesis, TGFbeta1 activity, fibronectin mRNA expression and TGFbeta1 receptors after toremifene treatment in normal, fibroma and desmoid fibroblasts. We evaluated GAG and collagen synthesis with (3)H-glucosamine and (3)H-proline incorporation, TGFbeta1 activity with the ELISA method, TGFbeta1 receptor affinity with (125)I-TGFbeta1 binding and total RNA with Northern blot analysis. GAG and collagen synthesis, TGFbeta1 activity and fibronectin levels were higher in fibroma and desmoid than normal fibroblasts. The increase was greater in desmoid than fibroma tumour cells. Toremifene treatment reduced GAG and collagen synthesis, TGFbeta1 activity and fibronectin levels in all cell cultures. The percentage reduction in GAG was similar in all cultures; the reduction in collagen synthesis and TGFbeta1 activity was the highest in desmoid fibroblasts. TGFbeta1 receptors were higher in fibroma and desmoid cells than controls. Toremifene reduced TGFbeta1 receptors only in desmoid fibroblasts, with no effect on the changes in type I, II, and III receptors. Our data show that toremifene modifies the ECM components that regulate cytokine activity and cell migration. The reduction in receptor number only in desmoid cells suggests that toremifene may reduce TGFbeta1's affinity for its receptors. Synthesis of a substance regulating protein kinase activity, which is directly involved in the link between TGFbeta1 and its receptors, cannot be excluded. 相似文献
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In five patients, aged 4 days to 20 months, the left pulmonary artery was inadvertently ligated at the time of attempted closure of the patent ductus arteriosus. The complication was recognized in these patients between 1 day and 5 years later from findings of chest radiography, two-dimensional echocardiography with spectral analysis of Doppler shifted echoes, and angiography. In three patients, the presence of asymmetric pulmonary blood flow on chest radiographs obtained after surgery initially suggested the diagnosis. In the other two patients with bronchopulmonary dysplasia, the diagnosis was made by means of two-dimensional echocardiography and Doppler spectra in one and angiography in the other. On angiograms, the left pulmonary artery distal to the ligation was visualized by delayed opacification from aortic collaterals in three patients and by means of pulmonary venous wedge injection in one. Radiographic and echocardiographic examination with Doppler spectra may permit prompt diagnosis and early correction of this complication. 相似文献
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Osmolar stimulation of vasopressin secretion in man: comparison of various protocols 总被引:1,自引:0,他引:1
The osmolar stimulation of vasopressin (AVP) release has been studied in 5 healthy subjects using two comparative protocols (infusion of 5% NaCl over 2 h vs 2.5% NaCl over 3 h). As AVP may be secreted by episodic bursts, AVP plasma concentrations were determined both in discrete plasma samples and in integrated samples drawn continuously by a pump over periods of 30 min. There was an earlier rise of plasma osmolality and AVP during the 5% NaCl infusion, but the final maximal value of plasma AVP did not differ in the two protocols. Plasma AVP rose from 1.3 +/- 0.7 to 3.8 +/- 1.5 during the 2.5% NaCl infusion and from 1.1 +/- 0.1 to 3.9 +/- 0.6 pg/ml during the 5% NaCl infusion. In both protocols a significant correlation obtained between the discrete and the integrated values of plasma AVP (r = 0.77 and r = 0.84 respectively, P less than 0.05). These results demonstrate that the two protocols of osmolar stimulation are equipotent in releasing AVP and do not induce episodic secretion. 相似文献
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磷酸二酯酶5(PDE5)影响环磷酸鸟苷(cGMP)维持血管平滑肌紧张性的生理学效应,在阴茎海绵体的静脉系统和肺血管系统中尤为明显。 相似文献
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Hospital evaluation is a fundamental process to identify medical units' objective compliance, to analyze efficiency of resource use and allocation, institutional values and mission alignment, patient safety and quality standards, contributions to research and medical education, and the degree of coordination among medical units and the health system as a whole. We propose an evaluation system for highly specialized regional hospitals through the monitoring of performance indicators. The following are established as base thematic elements in the construction of indicators: safe facilities and equipment, financial situation, human resources management, policy management, organizational climate, clinical activity, quality and patient safety, continuity of care, patients' and providers' rights and obligations, teaching, research, social responsibility, coordination mechanisms. Monitoring refers to the planned and systematic evaluation of valid and reliable indicators, aimed at identifying problems and opportunity areas. Moreover, evaluation is a powerful tool to strengthen decision-making and accountability in medical units. 相似文献
60.
Zaglia E De Leo D Lanzara G Urbani U Dolci M 《Journal of Forensic and Legal Medicine》2007,14(4):231-234
The installation of airbags in motor vehicles, in association with the use of seat belts, has reduced the incidence of head injuries, as well as significantly decreasing morbidity and mortality in motor vehicle accidents. Nevertheless, the literature on the subject increasingly refers to lesions related to airbag deployment. These are usually minor, but in certain circumstances, severe and fatal injuries can result. This is a case report of serious injury due to airbag deployment, involving a restrained driver who suffered occipital condylar injury when his airbag deployed in a frontal collision. The range of airbag associated injuries is reported and predisposing factors, such as the probable proximity to the airbag housing, is discussed. 相似文献