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BACKGROUND: Epidermal growth factor receptor (EGFR) is overexpressed in many types of cancers, especially colorectal cancer (CRC), and seems to reflect more aggressive histological and clinical behaviors. The aim of this study was to evaluate EGFR immunohistochemical reactivity in CRC biopsies, and to analyze its relationship with various histological and clinical characteristics and survival. PATIENTS AND METHODS: A composite EGFR score, obtained by multiplying the grade (% positive cells) by the intensity of labeling (0-9) was used to define patients with low or high EGFR expression whose clinicopathological features were then compared. Univariate tests and multivariate Cox proportional hazards model were applied for data analysis. RESULTS: Tissue sections from 150 CRC patients with a median follow-up of 40 months were examined. Median patient age at diagnosis was 70 years (range 38-89 years). EGFR reactivity was positive for 143 patients (97%) and high for 118 (80%). According to multivariate analysis, EGFR overexpression was significantly associated with tumor stage, with a higher percentage of EGFR overexpression in T3 than T4 (P=0.003) and not with overall survival. CONCLUSIONS: EGFR was overexpressed in this CRC patient population and was significantly associated with TNM (tumor-node-metastasis) stage T3. In the context of a new therapeutic strategy using EGFR-targeted therapies, although EGFR remains a controversial prognostic factor, this expression-stage association may play a crucial role in a decision to initiate an adjuvant treatment.  相似文献   
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In recent years, there has been increasing interest in the relationship between dental occlusion and body posture both among people and in scientific literature. The aim of the present longitudinal study is to investigate the effects of an experimental occlusal interference on body posture by means of a force platform and an optoelectronic stereophotogrammetric analysis. An occlusal interference of a 0‐ to 2‐mm‐thick glass composite was prepared to disturb the intercuspal position while not creating interference during lateral or protrusive mandibular excursions. Frontal and sagittal kinematic parameters, dynamic gait measurements and superficial electromyographic (SEMG) activity of head and neck muscles were performed on 12 healthy subjects. Measurements were taken 10 days before the application of the occlusal interference, and then immediately before the application, the day after it, and at a distance of 7 and 14 days under four different exteroceptive conditions. The outcomes of this study show that an occlusal interference does not modify significantly over time static and dynamic parameters of body posture under different exteroceptive conditions. It has a minimal influence only on the frontal kinematic parameters related to mandibular position, and it induces a transient increase of the activity of masticatory muscles. In this study, the experimental occlusal interference did not significantly influence the body posture during a 14‐day follow‐up period.  相似文献   
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Haematemesis is a worrying sign, generally related to acute upper gastrointestinal bleeding and potentially life-threatening condition. We present a case of a 15-year-old Caucasian girl who was belatedly diagnosed with oral bleeding because it was not related to the most common aetiologic factors. In fact, she was undergoing orthodontic treatment with a Nance palatal arch, an appliance used to reinforce anchorage during teeth movements. In her case haematemesis was a sign of inflammation and necrosis occurring in the palatal mucosa, under the acrylic button of palatal arch. The appliance was removed; antibiotic and Chlorhexidine 0.12% were recommended. After a 6-week follow-up, no pathological signs were present and the orthodontic treatment was resumed. Both physicians and dentists should be aware of the possible side effect of the Nance palatal arch use; this could help in achieving a diagnosis and providing a correct treatment. Orthodontists should avoid excessive compression over the palatal mucosa and check the appliance condition during every follow-up in order to avoid necrosis of the palatal mucosa.  相似文献   
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OBJECTIVE: Health consumption and health status in SLE in three countries with different health funding structures were compared. METHODS: Seven hundred and fifteen SLE patients (Canada 231, USA 269, UK 215) were surveyed semi-annually over 4 yr for health resource utilization and health status. Cross-country comparisons of (i) cumulative health expenditure (calculated by applying 2002 Canadian prices to resources in all countries) and (ii) disease damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index, SLICC/ACR DI) at study conclusion were performed after adjustment. Missing expenditure and damage data were managed through multiple imputation using best predictive regressions with all available data from all patients as potential covariates. RESULTS: Four hundred and eighty-five patients provided data at study entry and conclusion and at least four resource questionnaires (Canada 162, USA 157, UK 166); 41 died (Canada 13, USA 18, UK 10); 189 withdrew, were lost to follow-up or provided data at entry and conclusion but fewer than four resource questionnaires (Canada 56, USA 94, UK 39). At conclusion, after imputation, in Canada, the USA and the UK respectively, mean cumulative costs per patient over 4 yr [95% confidence interval (CI)] were $15,845 (13,509, 18,182), $20,244 (17,764, 22,724) and $17,647 (15,557, 19,737) and mean changes in SLICC/ACR DI were 0.49 (0.39, 0.60), 0.63 (0.52, 0.74) and 0.48 (0.39, 0.57). After adjustment for baseline differences, on average (95% CI), Canadian and British patients utilized 20% (8%, 32%) and 13% (1%, 24%) less resources than patients in the USA respectively, but experienced similar health outcomes. CONCLUSION: Despite patients in the USA incurring higher health expenditures, they did not experience superior health outcomes.  相似文献   
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We have investigated the possible effect of substance P (SP), a main mediator of neurogenic inflammation, on the growth of capillary vessels in vivo, and on the proliferation of cultured endothelial cells in vitro. Slow release preparations of SP were implanted into the avascular cornea of New Zealand White rabbits and vessel growth was monitored daily through a slit lamp stereomicroscope. SP (1-5 micrograms/pellet) induced a marked neovascularization. A selective NK-1 receptor agonist [beta-Ala4, Sar9, Met(O2)11]-SP(4-11) also induced neovascularization. The addition of SP to serum-free cultured endothelial cells, isolated from bovine adrenals (BACE) and from human umbilical cord veins (HUVE), increased proliferation of both cell lines in a concentration-dependent manner with maximal activity at 10(-8) M (BACE) and 10(-10) M (HUVE). The selective NK-1 receptor agonist induced a similar proliferative action on both cell lines, while the selective NK-2 receptor agonist [beta-Ala8]-NKA(4-10) and the selective NK-3 receptor agonist [MePhe7]-NKB had no significant effect. Two different SP antagonists [D-Pro2, D-Trp7,9]-SP and [D-Pro4, D-Trp7,9,Phe11]-SP (4-11) blocked the response to SP. These findings indicate that SP can directly stimulate the process of neovascularization, probably through induction of endothelial cell proliferation. This hitherto unraveled activity of SP could play a key role in the trophic action produced by activation of the efferent function of peripheral endings of primary sensory neurons.  相似文献   
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BACKGROUND/AIMS: A delay in recognizing and treating an inflamed gallbladder may increase the risk of a necrotic evolution and represent a critical factor affecting the progression of the inflammatory process. Aim of the study is to assess the therapeutic attitude in patients with histologically proved gangrenous cholecystitis, to find out whether it could play a role in the progression of the inflammatory condition. METHODOLOGY: Twenty-seven patients with gangrenous cholecystitis at histology were compared with a matched-control group with phlegmonous cholecystitis. RESULTS: Age, gender, ASA score, and concomitant diseases did not differ significantly in both groups. WBC was significantly higher (P = 0.026) in patients with gangrene. Ultrasounds were unhelpful in identifying the severity of the disease. Patients with gangrenous gallbladder showed a significantly increased (P = 0.0006) admission delay compared with controls (104.3+/-15.3 hours vs. 59.7+/-7.7 hours). Surgeon's delay, morbidity and mortality were not different in both groups. CONCLUSION: Patient's delay before hospitalization may represent a crucial factor in the progression toward a more severe disease in acute cholecystitis. The time between symptoms onset and hospital admission (and consequently surgery) was significantly longer in patients with gangrenous cholecystitis, further emphasizing the need for an early (if not urgent) surgical treatment in acute cholecystitis, even with mild symptoms.  相似文献   
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