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51.
The purpose of this study was to evaluate the effect of radial artery reconstruction after radial forearm flap elevation and to study whether a vein graft can stay patent in this position. Ten consecutive oral cancer patients were included in the study. Pre-operative Allen's test was performed, and the flow velocity of both radial and ulnar arteries was recorded using colour Doppler ultrasonography. After flap elevation, the radial artery was reconstructed using the cephalic vein of the donor forearm as a free vein graft. The reconstructed artery was completely covered with surrounding skin, while the actual donor defect was covered with a split thickness skin graft. Colour Doppler ultrasonography was performed at 1–2 weeks and at 6–12 months post-operatively to record long-term patency. Radial artery reconstruction did not prolong the operations. All donor sites healed uneventfully. All of the reconstructed arteries were patent at the post-operative controls. In one patient, graft flow was missing on the first post-operative day but normal in the follow-up. A vein graft can remain patent with a very high success rate after radial artery reconstruction. A negative Allen’s test is not an absolute contraindication of a radial forearm flap as radial artery reconstruction can be performed.  相似文献   
52.
Population ageing and improved healthcare may lead to an increase in the prevalence of stroke. The aim of this study is to investigate the prevalence of stroke and stroke-related disability in a population sample resident in Aosta, Italy. The information was collect using a simple questionnaire for first ever stroke in the past combined with the analysis of the patients’ medical records and integrated with the information reported by six general practitioners. 102 cases of stroke were identified in the study population of 6,930 subjects, for an overall prevalence per 1,000 inhabitants of 1.4 (95% CI 0.81–1.99), which increased to 4.79 (95% CI 3.29–6.29) in subjects aged ≥65 years. Fifty-nine percent of the cases were completely or partially dependent (Rankin scores of 2–5). At the time of interview, 72% were living at home. Our data do not reveal any increase in the prevalence of stroke, possibly because of a reduced incidence of the disease.  相似文献   
53.
Neurological Sciences - Few epidemiological studies have assessed the risk of parkinsonisms after prolonged use of neuroleptics. We aimed to examine the long-term risk of degenerative parkinsonisms...  相似文献   
54.
BACKGROUND AND OBJECTIVES: Neuroblastoma is one of the most frequent childhood cancers and a major cause of death from neoplasias of infancy. Although a wealth of studies on its molecular bases have been carried out, little conclusive information about its origin and evolution is available. EVIDENCE AND INFORMATION SOURCES: Some intriguing findings have correlated neuroblastoma development with aberrations of two pivotal cellular processes generally altered in human cancers, namely cell division cycle and apoptosis. Indeed, it has been reported that neuroblastoma cell lines show accumulation of Id2 protein, a factor which is able to hamper the pRb protein antiproliferative activity. STATE OF THE ART: The increased Id2 is due to N-myc gene amplification and overexpression, a phenomenon frequently observed in neuroblastoma and an important independent negative marker. Moreover, neuroblastoma cells are frequently characterized by increased levels of survivin, an inhibitor of the apoptotic response, and by a deficiency of procaspase 8, a key intermediate of the programmed cell death cascade. These two events, probably, make neuroblastomas more resistant to programmed cell death. These recent findings might suggest that neuroblastoma cells have acquired the capability to proliferate easily and die difficultly. PERSPECTIVES: The mechanistic meaning of these data will be discussed in the present review. Moreover, we will suggest new therapeutic scenarios opened up by the described alterations of cell cycle and apoptosis engines.  相似文献   
55.
Aim of this study was the literature review regarding esophageal perforations and fistulas. We examined the most common causes, clinical findings (symptoms and signs), laboratory and imaging studies for differential diagnosis and complications. Finally, we examined the surgical or endoscopic treatment and the prognosis.  相似文献   
56.
It has been widely demonstrated that neo-angiogenesis and its mediators (i.e. vascular endothelial growth factor), represent useful indicators of poor prognosis in non small cell lung carcinoma. In order to verify whether neovascularization and vascular endothelial growth factor may be considered useful markers of clinical outcome also in the small cell lung cancer subgroup, we retrospectively investigated a series of 75 patients with small cell lung carcinoma treated by surgery between 1980 and 1990. Immunohistochemically-detected microvessels and vascular endothelial growth factor expressing cells were significantly associated with poor prognosis, as well as with nodal status and pathological stage. In fact, patients whose tumours had vascular count and vascular endothelial growth factor expression higher than median value of the entire series (59 vessels per 0.74 mm(2) and 50% of positive cells, respectively), showed a shorter overall and disease-free survival (P=0.001, P=0.001; P=0.008, P=0.03). Moreover, the presence of hilar and/or mediastinal nodal metastasis and advanced stage significantly affected overall and disease-free interval (P=0.00009, P=0.00001; P=0.0001, P=0.00001). At multivariate analysis, only vascular endothelial growth factor expression retained its influence on overall survival (P=0.001), suggesting that angiogenic phenomenon may have an important role in the clinical behaviour of this lung cancer subgroup.  相似文献   
57.
A dysfunctional relationship between parents and children can influence cognitive and emotional development and contribute to the development of psychiatric disorders, particularly panic disorder (PD). With the aim of exploring childhood experiences of parenting in PD patients, we compared subjectively perceived climate and objective recall by administering the Parental Bonding Instrument and 10 adjunctive items to 22 out-patients and 22 matched controls. Our analysis showed that DSM-III-R-diagnosed PD patients reported their parents to be significantly less caring than did the control group, while there was no significant difference in objective recall of parenting experiences.  相似文献   
58.
The acute hemodynamic effects of nifedipine were assessed In 12 patients with severe isolated aortic Insufficiency during control conditions and 30 minutes after administration of nifedipine (20 mg sublingually). Left ventricular end-diastollc pressure decreased from 19 ± 8 (mean ± standard deviation) to 9 ± 5 mm Hg (probability [p] < 0.0001), mean aortic pressure from 98 ± 12 to 80 ± 9 mm Hg (p < 0.0001), systemic vascular resistance from 1,135 ± 280 to 794 ± 176 dynes·s·cm?5 (p < 0.0002) and rate-pressure product from 11,732 ± 1,727 to 10,022 ± 1,103 mm Hg+ beats/min (p < 0.01). Forward cardiac index increased by 24 percent, from 3.8 ± 1.1 to 4.4 ± 0.8 liters/min per m2 (p < 0.04). Left ventricular end-diastolic volume, ejection fraction and total stroke work index did not change significantly. Regurgitant fraction, measured in five patients, changed parallel with systemic vascular resistance. Left ventricular function was maintained while both preload and afterload were decreased. Regurgitant flow was moderated and myocardial oxygen demand decreased. This hemodynamically favorable condition, due to nifedlpine, is clinically important and suggests the need for further therapeutic trials.  相似文献   
59.
Magnetic Resonance Imaging is gaining a prominent role in the routine clinical investigation. To further improve this technique it is crucial that contrast agents are developed with more optimal organ specificity. This will not only result in a better diagnostic efficiency but also in a reduction of the amount of the agent administered. A combination of techniques has been employed to increase the target selectivity of the contrast agent and thereby the feasibility to visualize different organs. The organ targeting is based on the understanding of the mechanisms involved in the interaction of the agent with plasma proteins (albumin in particular) as well as the different membrane transporters involved in the uptake and in the excretion of the agent from the organ. The physicochemical properties of the contrast agents play a major role in the interaction with these various proteins. In this review we address the relationship between the structure of the contrast agents and their binding to different plasma proteins and membrane transporters in different organs, with special reference to the liver and kidney. The present and potentially future applications of these concepts in the clinical setting are also discussed.  相似文献   
60.
BACKGROUND: It is generally acknowledged that calcium excretion is a determinant of bone mineral density. Since data confirming this hypothesis are not conclusive, the present study evaluates the relationship between calcium excretion and volumetric bone mineral density (vBMD) in a sample of general population mostly composed of elderly subjects. METHODS: This relationship was studied in 595 subjects in good health (M/F 302/293), selected from the InCHIANTI population, an epidemiologic survey on aging in Tuscany (Italy). Of these subjects, 432 (72.6%) were 65 years old or older. Trabecular and cortical apparent vBMDs were measured by peripheral quantitative computed tomography at right tibia and standardized to age and body mass index (BMI) in each gender (z-score). RESULTS: Men in the highest tertile of calcium excretion had significantly lower trabecular vBMD, and were more likely to have a trabecular z-score of -1 or less. These results were confirmed in men older than 64 years, but not in women and younger men. Sodium excretion and 25-hydroxycolecalciferol (25(OH)D) were greater in men and women in the highest tertile. No differences among tertiles were observed for cortical vBMD, circulating levels of interleukin-1beta and interleukin-6, and intake of principal nutrients and calcium. The lower levels of vBMD z-score were confirmed in men in the highest tertile of calcium excretion, standardized to creatinine clearance, sodium excretion, plasma calcium, and logarithm of circulating 25(OH)D, and resulted to be associated with calcium excretion at multiple regression analysis in men. CONCLUSION: High calcium excretion is associated with a decreased trabecular BMD in elderly men and may predispose men to trabecular bone loss.  相似文献   
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