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41.
The mucosa of the gastric stump is considered at greater risk of dysplastic and neoplastic changes than that of the intact stomach. The combination of enteric reflux and Helicobacter pylori infection may have a synergistic damaging effect on the mucosa of the gastric remnant, both producing and increasing mucosal proliferation. The aim of this study was to assess whether the occurrence of H. pylori infection in the remnant mucosa of partially gastrectomized subjects for peptic ulcer disease is associated with an increase of the mucosal precursor lesions of malignancy. A series of 151 subjects who underwent partial gastrectomy for peptic ulcer disease were submitted to upper digestive endoscopy for long-term surveillance. Biopsy specimens of the gastric stump were tested for the occurrence of H. pylori infection and for the presence of precancerous mucosal lesions. The prevalence of H. pylori colonization in the remnant stomach was less than 30% and similar in subjects with different time intervals between gastrectomy and endoscopy. Age at surgery (χ2: p = 0.03) and H. pylori infection (χ2: p = 0.002) were significantly associated with the grading of mucosal lesions. The prevalence of normal mucosa was 10 times higher in H. pylori-negative patients as in H. pylori-positive ones (22.0% vs. 2.4%), and the prevalence of intestinal metaplasia was four times higher in H. pylori-positive patients than in H. pylori-negative ones (19.6% vs. 4.6%). We concluded that H. pylori infection may play a causal role in the development of gastric lesions in the operated stomach.  相似文献   
42.
Osteoporosis is a silent disease without any evidence of disease until a fracture occurs. Approximately 200 million people in the world are affected by osteoporosis and 8.9 million fractures occur each year worldwide. Fractures of the hip are a major public health burden, by means of both social cost and health condition of the elderly because these fractures are one of the main causes of morbidity, impairment, decreased quality of life and mortality in women and men. The aim of this review is to analyze the most important factors related to the enormous impact of osteoporotic fractures on population. Among the most common risk factors, low body mass index; history of fragility fracture, environmental risk, early menopause, smoking, lack of vitamin D, endocrine disorders(for example insulin-dependent diabetes mellitus), use of glucocorticoids, excessive alcohol intake, immobility and others represented the main clinical risk factors associated with augmented risk of fragility fracture. The increasing trend of osteoporosis is accompanied by an underutilization of the available preventive strategies and only a small number of patients at high fracture risk are recognized and successively referred for therapy. This report provides analytic evidences to assess the best practices in osteoporosis management and indications for the adoption of a correct healthcare strategy to significantly reduce the osteoporosis burden. Early diagnosis is the key to resize the impact of osteoporosis on healthcare system. In this context, attention must be focused on the identification of high fracture risk among osteoporotic patients. It is necessary to increase national awareness campaigns across countries in order to reduce the osteoporotic fractures incidence.  相似文献   
43.
The concept of ideal tumor surgery is to remove the neoplastic tissue without damaging adjacent normal structures. High-intensity focused ultrasound (HIFU) was developed in the 1940s as a viable thermal tissue ablation approach. In clinical practice, HIFU has been applied to treat a variety of solid benign and malignant lesions, including pancreas, liver, prostate, and breast carcinomas, soft tissue sarcomas, and uterine fibroids. More recently, magnetic resonance guidance has been applied for treatment monitoring during focused ultrasound procedures (magnetic resonance–guided focused ultrasound, MRgFUS). Intraoperative magnetic resonance imaging provides the best possible tumor extension and dynamic control of energy deposition using real-time magnetic resonance imaging thermometry. We introduce the fundamental principles and clinical indications of the MRgFUS technique; we also report different treatment options and personal outcomes.  相似文献   
44.

Purpose

The aim of this study was to analyse factors predicting the diagnostic accuracy of computed tomography (CT)-guided transthoracic fine-needle aspiration (TTFNA) for solid noncalcified, subsolid and mixed pulmonary nodules, with particular attention to those responsible for false negative results with a view to suggesting a method for their correction.

Materials and methods

From January 2007 to March 2010, we retrospectively reviewed the CT images of 198 patients of both sexes (124 males and 74 females; mean age, 70 years; range age, 44–90) used for the guidance of TTFNA of pulmonary nodules. Aspects considered were: lesion size and density, distance from the pleura, and lesion site. Multiplanar reformatted images (MPR) were retrospectively obtained in the sagittal and axial oblique planes relative to needle orientation.

Results

The overall diagnostic accuracy of TTFNA CTguided biopsy was 86% for nodules between 0.7 and 3 cm, 83.3% for those between 0.7 and 1.5 cm, and 92% for those between 2 and 3 cm. Accuracy was 95.1% for solid pulmonary nodules, 84.6% for mixed nodules, and 66.6% for subsolid nodules. The diagnostic accuracy of CT-guided TTFNA in relation to the distance between the nodule and the pleural plane was 95.6% for lesions adhering to the pleura and 83.5% for central ones. The diagnostic accuracy was 84.2% for the pulmonary upper lobe nodules, 85.3% for the lower lobe and 90.9% for those in the lingula and middle lobe. In 75% of false negative and inadequate/insufficient cases the needle was found to lie outside the lesion, after reconstruction of the needle path by MPR.

Conclusions

The positive predictive factors of CT-guided TTFNA are related to the nodule size, density and distance from the pleural plane. The most common negative predictive factor of CT-guided TTFNA is the wrong position of the needle tip, as observed in the sagittal and axial oblique sections of the MPR reconstructions. The diagnostic accuracy of CT-guided TTFNA can therefore be improved by using the MPR technique to plan the needle path during the FNA procedure.  相似文献   
45.
The presence of cirrhosis is the only risk factor that is advocated for recurrence of hepatocellular carcinoma (HCC) 2 years after hepatic resection compared with noncirrhotic control subjects; however, data for cohorts of exclusively patients with cirrhosis are lacking. This study was designed to assess risk factors and annual incidence of early (<2 years) and late (>2 years) recurrence after resection of cirrhosis and to compare these findings with those of patients with cirrhosis enrolled in HCC surveillance programs (HCC occurrence). Data from 204 patients with cirrhosis resected for HCC and 150 surveilled for cirrhosis were retrospectively collected and compared using propensity score matching to overcome biases of nonrandomized study. Risk factors for early recurrence (incidence = 21.8%/year) were higher serum alpha-fetoprotein (AFP) levels, poorly differentiated tumor, and presence of microvascular invasion (P < 0.05). Risk factors for both late recurrence (18.4%/year) and HCC occurrence (3.3%/year) were male gender, older age, and higher serum transaminase levels; multiple primary tumors and higher AFP were additional risk factors for late recurrence and HCC occurrence respectively (P < 0.05). After propensity adjustment, resected patients with less than two risk factors for late recurrence showed an annual incidence of HCC (6.2%/year) similar to that of surveilled patients with ≥2 risk factors (5.8%/year; P = 0.898). Early and late recurrence of HCC for patients with cirrhosis after resection have distinct risk factors. Annual incidence of HCC 2 years or more after resection may be similar to that of general patients because the same risk factors are involved; assessment of these characteristics could be useful in tailoring clinical management.  相似文献   
46.
Peri-anastomotic graft stenosis is a possible complication of coronary artery bypass graft operations. Early failure of myocardial revascularization may result from graft stenosis with inherent difficulties in perioperative diagnosis and subsequent management. We report the case of a 58-year-old man who experienced early preanastomotic left internal thoracic artery bypass stenosis that progressively resolved during a 2-year period without reoperation or interventional angioplasty. Although the mechanisms underlying graft stenosis remain unclear, this case emphasizes the role of repeated coronary angiography in the choice of treatment.  相似文献   
47.
Chemotaxis, mitogenesis, motogenesis and cytoprotection are common cellular events involved in both tumourigenesis and tissue repair, which appear amplified upon growth factors exposure. Epidermal growth factor (EGF) promotes these events in epithelial and mesenchymal cells through the binding to a specific tyrosine kinase receptor. In experimental oncology settings, EGF does not initiate malignant transformation but exhibits ‘tumour promotion’. These observations have raised doubts on the clinical use of EGF despite solid demonstrations of efficacy in experimental conditions and clinical trials. The results of a Pubmed and Bioline investigation on EGF clinical uses and preclinical safety data are presented here. EGF topical administration has been used since 1989 to enhance the healing process of a variety of peripheral tissues wounds (16 clinical reports), as well as its intravenous, oral and rectal administration for gastrointestinal damages (11 clinical reports). EGF therapeutic efficacy and excellent tolerability seem demonstrated. Lack of long‐term adverse effects is highlighted in those studies with 6, 12 and 24 months of patients follow‐up. Although post‐treatment follow‐up may fall short for malignant growth, there are no reports on evidences linking EGF clinical use with cancer. A multicentre, nationwide survey in Cuba, 15 years after randomly using silver sulphadiazine with EGF or not in burn victims yielded that cancer incidence was comparable between EGF‐treated and control subjects and that such incidence rate does not differ from the age‐matched national incidence for those 15‐year period. All the animal species subjected to long‐term EGF systemic administration exhibit dose‐dependent and reversible epithelial organs hyperplasia with no changes in cells phenotypic differentiation. Histotypic pre‐malignant markers were not identified. The results emerged from co‐carcinogenesis studies and from transgenic mice over‐expressing EGF are conflicting and indicate that EGF overexposure, either innate or postnatal, may not be sufficient to transform cells. The ability of EGF to heal injured tissues in life‐threatening scenarios or to assist in preventing physical and social disability advocates for its clinical use under a rational medical risk/benefit balance.  相似文献   
48.
Objective: Increased dimension of the aortic root and proximal aorta is considered a significant risk factor for catastrophic events that involve the ascending aorta. The objective of this study was to determine the possible correlation between pre-dissection aortic diameter and the occurrence of Stanford type A aortic dissection. Methods: Samples of dissected ascending aortas were obtained from 220 patients at the time of their operation. Two groups were identified: patients with connective tissue disorders (Group 1, n = 94) and those without (Group 2, n = 126). Measurements of the true (intimal) lumen were conducted and extrapolated as reliable approximation of pre-dissection aortic diameter. The possible association of intimal diameter with anthropometric and demographic data was analyzed. Results: Median aortic diameter was, respectively, 41.8 and 41.3 mm for patients with and without connective tissue disorders (41.4 mm for the entire cohort). Data analysis indicated that 57% of patients had aortic diameter above 40 mm, while patients with frank aneurysm accounted only for 10%; this proportion was higher in Group 1 compared to Group 2 (17.2% vs 4.7%). Poor or no correlation was demonstrated between aortic size and any of the anthropometric or demographic variables essayed. Significant subgroup differences were found among patients with a history of cigarette smoking, hypertension, diabetes, chronic renal insufficiency, and bicuspid aortic valve. Conclusion: Although aortic diameter remains a strong indication for preventive surgery in patients with inherited connective tissue disorders, acute aortic dissection occurs rarely in the setting of true ascending aortic aneurysms, and despite normal or near-normal aortic size in more than one-third of subjects. Dissection superimposing on small aortic diameters can be regarded as an expression of substantial functional tissue susceptibility to aortic catastrophic events.  相似文献   
49.
Background  Viscosupplementation, with hyaluronan derivates injected into the intra-space of osteoarthritic joints, is now widely used for the treatment of knee osteoarthritis. This study evaluates the results in terms of pain and disability of intra-articular injections of hyaluronan derivates into the ankle joint in patients suffering from grade II primary or secondary osteoarthritis of the ankle. Methods  Twenty-one patients with a painful ankle and radiographic evidence of grade II osteoarthritis had three weekly intra-articular injections of 2 ml of hylan G-F 20 (10 mg/ml) into the ankle joint. The primary clinical outcome measurement was the ankle osteoarthritis score (AOS) at the baseline, and at 6, 12 and 18 months. Results  Significant improvement of the AOS from baseline was seen after 6 months (p=0.0001). This improvement was maintained over time with no further changes at 12- and 18-month follow-ups. Regarding pain, the AOS improved over time from the baseline to the 18-month follow up and became statistically significant at the 12- and 18-month follow-ups (p<0.05).  相似文献   
50.
Stem cell populations have been shown to be extremely versatile: they can generate differentiated cells specific to the tissue in which they reside and descendents that are of different germ layer origin. This raises the possibility of obtaining neuronal cells from new biological source of the same adult human subjects. In this study, we found that epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) cooperated to induce the proliferation, self-renewal, and expansion of neural stem cell-like population isolated from several newborn and adult mouse tissues: muscle and hematopoietic tissues. This population, in both primary culture and secondary expanded clones, formed spheres of undifferentiated cells that were induced to differentiate into neurons, astrocytes, and oligodendrocytes. Brain engraftment of the somatic-derived neural stem cells generated neuronal phenotypes, demonstrating the great plasticity of these cells with potential clinical application.  相似文献   
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