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81.
Survival after invasive bladder cancer has improved less than that of other common non-skin cancers. In many types of malignancy, treatment failure has been attributed to therapy-resistant stem-like cancer cells. Our aim was therefore to determine identities of stem cell marker-positive cells in bladder cancer tissue and to investigate possible associations between these cells and different forms of bladder neoplasia. We investigated tissue from 52 patients with bladder neoplasia and 18 patients with benign bladder conditions, from a cohort that had been previously described with regard to diagnosis and outcome. The samples were analysed immunohistologically for the stem cell markers aldehyde dehydrogenase 1 A1 (ALDH1) and CD44, and markers of cell differentiation. The majority of stem cell marker-positive cells were located in connective tissue, and a smaller fraction in epithelial tissue. Stem cell marker-positive cells exhibiting possible stem cell characteristics included cells in deeper locations of benign and malignant epithelium, and sub-endothelial cells in patients with or without neoplasia. Stem cell marker-positive cells with non-stem cell character included stellate cells, mast cells, endothelial cells, foamy histiocytes, and neurons. Significantly, ALDH1+ stellate cells and ALDH1+ mast cells were reduced in number in stroma of benign-appearing mucosa of bladder cancer patients. The stem cell markers ALDH1 and CD44 label several types of differentiated cells in bladder tissue. ALDH1+ stellate cells and mast cells appear to be reduced in stroma of normal-appearing mucosa of bladder cancer patients, and may be part of a “field effect” in cancer-near areas.  相似文献   
82.
Mantle cell lymphoma (MCL) is an aggressive B cell lymphoma, where survival has been remarkably improved by use of protocols including high dose cytarabine, rituximab and autologous stem cell transplantation, such as the Nordic MCL2/3 protocols. In 2008, a MCL international prognostic index (MIPI) was created to enable stratification of the clinical diverse MCL patients into three risk groups. So far, use of the MIPI in clinical routine has been limited, as it has been shown that it inadequately separates low and intermediate risk group patients. To improve outcome and minimize treatment‐related morbidity, additional parameters need to be evaluated to enable risk‐adapted treatment selection. We have investigated the individual prognostic role of the MIPI and molecular markers including SOX11, TP53 (p53), MKI67 (Ki‐67) and CCND1 (cyclin D1). Furthermore, we explored the possibility of creating an improved prognostic tool by combining the MIPI with information on molecular markers. SOX11 was shown to significantly add prognostic information to the MIPI, but in multivariate analysis TP53 was the only significant independent molecular marker. Based on these findings, we propose that TP53 and SOX11 should routinely be assessed and that a combined TP53/MIPI score may be used to guide treatment decisions.  相似文献   
83.
Abstract – Aims: The aim of this study was to retrospectively evaluate iatrogenic dental root damage, caused by two different techniques that utilized bone anchor screws, for intermaxillary fixation (IMF) in orofacial trauma. Materials and methods: The techniques used included either predrilled or drill‐free bone anchor screws. A total of 123 patients who required IMF were evaluated (97 men and 26 women). Sixty‐four patients were treated in the predrilled group, and 59 patients were treated in the drill‐free group. The data were collected over an 8‐year period and were analyzed using crosstabs and Fisher’s exact test. Results: Injuries to dental roots were found only in the predrilled group. Twenty‐nine patients (45.3%) were injured at the time of surgery. One year after surgery, 10 patients (15.6%) had permanently injured dental roots. There was a significant difference in injury rates between the predrilled and drill‐free groups 1 year after surgery (P < 0.001). Conclusion: There is an increased potential risk of iatrogenic injury and permanent damage to the dental roots when a technique that involves predrilled holes for bone anchor screws is used.  相似文献   
84.
The prognostic value of grading follicular lymphoma has been debated since the 1980s. There is consensus that World Health Organization (WHO) grades 1 and 2 are indolent, but not whether grades 3A or 3B are aggressive. We retrospectively reviewed the follicular lymphoma diagnoses according to the 2008 WHO classification in all diagnostic specimens from a population-based cohort of 505 patients with a median follow-up time of 10·0years (range, 4·6-16·0). After excluding 43 patients with concomitant diffuse large B-cell lymphoma, 345 remained with grade 1-2, 94 with grade 3A, and 23 with grade 3B follicular lymphoma. Grades 1-2 and 3A seemed equally indolent, with indistinguishable clinical courses, even in patients receiving anthracyclines. Compared with grades 1-3A and independently of clinical factors, grade 3B correlated with higher mortality (P=0·008), but outcome was improved after upfront anthracycline-containing therapy (P=0·015). In contrast to grade 1-3A patients, grade 3B patients experienced no relapses or deaths beyond 5years of follow-up. Furthermore, patients with grade 3B were predominantly male and seldom presented with bone-marrow involvement. We conclude that follicular lymphoma grade 1-3A is indolent and incurable with conventional therapy. Grade 3B appears to be an aggressive but curable disease.  相似文献   
85.
Aluminum (Al) concentration was assessed in deciduous teeth in relation to sex, year of birth, tooth type, and the presence of caries and roots. Three hundred and twenty-three deciduous teeth from children born during the period 1952-93 in a county in southeast Sweden were sampled, and the Al content determined by graphite furnace atomic absorption spectrophotometry. The arithmetic mean of the Al concentration was 0.58 &#45 0.64 ppm dry weight (mean &#45 standard deviation) and differed significantly between incisors (1.05 &#45 1.04 ppm) and canines (0.48 &#45 0.50 ppm) and between incisors and molars (0.53 &#45 0.55 ppm). A significant difference was found between teeth with and without caries. No significant differences were found between sexes. The Al concentration correlated significantly with tooth weight for incisors (r =-0.47)and canines (r =-0.45) but not for molars (r = 0.03). No significant change in Al concentration was found over time. Caries-free deciduous molars are suggested as the most useful teeth for biological monitoring of aluminum.  相似文献   
86.
The aim of the present study was to compare concentrations of cytokines, matrix metalloproteinases (MMPs) and a metalloproteinase inhibitor (TIMP‐1) in gingival crevicular fluids (GCF) from sites with gingival inflammation in 28 young patients with Papillon‐Lefèvre syndrome (PLS), and in age‐ and gender‐matched controls. Each group consisted of 17 females and 11 males with a mean age of 11.0 years (range 4–22 years). In both groups, anterior upper sites with a clinical diagnosis of gingival inflammation and with pockets ≤3?mm were selected for sampling of GCF, which was carried out with filter disks inserted into the gingival crevice until saturated. The concentrations of cytokines (IL‐1α, IL‐1β, TNF‐α, and IL‐8), matrix metalloproteinases (MMP‐1, MMP‐3, MMP‐8, and MMP‐9), and their tissue inhibitor (TIMP‐1) were analysed using commercial ELISA kits. Significantly higher levels of IL‐1β (P?P?P?P?P?相似文献   
87.
88.
Aims This study aimed to examine the associations between cannabis use and work commitment Design We used a 25‐year panel survey initiated in 1985 with follow‐ups in 1987, 1989, 1993, 2003 and 2010. Registered data from a range of public registers were matched with individual responses for the entire period. Setting The panel survey was a nation‐wide study set in Norway. Participants A total of 1997 respondents born between 1965 and 1968 were included in the panel. Measurements Work involvement scale (WIS) was used to assess work commitment. Involvement with cannabis was based on self‐reported smoking of cannabis within the last 12 months and exposure to cannabis through friends. This information was categorized into ‘abstaining’, ‘exposed’, ‘experimented’ and ‘involved’. Control measures included socio‐economic background, mental health (HSCL‐10), education, work satisfaction, unemployment, receipt of social assistance, consumption of alcohol, alcohol‐related problems and use of other illicit drugs. Findings The level of work commitment was associated with involvement with cannabis. In 1993, when the respondents were in their mid‐20s, those who were involved or had experimented with cannabis displayed lower levels of work commitment than those who were abstaining or merely exposed to cannabis through friends (P < 0.05). Work commitment among those who experimented with cannabis converged towards the levels reported by abstainers and the exposed as they grew older, whereas those involved reported decreasing work commitment into adulthood (P < 0.001). Using linear regression models for panel data, an association with continued use of cannabis across the life‐course and a lowering of work commitment was established. Results remained significant even when controlling for a range of other factors known to be related to work commitment, such as socio‐economic background, education, labour market experiences, mental health and family characteristics (P < 0.05). Conclusions In Norway the use of cannabis is associated with a reduction in work commitment among adults.  相似文献   
89.
AIM: To investigate the prognostic value of CD44 variant 6 (CD44v6), a membranous adhesion molecule, in rectal cancer.METHODS: Altogether, 210 rectal cancer samples from 214 patients treated with short-course radiotherapy (RT, n = 90), long-course (chemo) RT (n = 53) or surgery alone (n = 71) were studied with immunohistochemistry for CD44v6. The extent and intensity of membranous and cytoplasmic CD44v6 staining, and the intratumoral membranous staining pattern, were analyzed.RESULTS: Membranous CD44v6 expression was seen in 84% and cytoplasmic expression in 81% of the cases. In 59% of the tumors with membranous CD44v6 expression, the staining pattern in the invasive front was determined as “front-positive” and in 41% as “front-negative”. The latter pattern was associated with narrower circumferential margin (P = 0.01), infiltrative growth pattern (P < 0.001), and shorter disease-free survival in univariate survival analysis (P = 0.022) when compared to the “front-positive” tumors.CONCLUSION: The lack of membranous CD44v6 in the rectal cancer invasive front could be used as a method to identify patients at increased risk for recurrent disease.  相似文献   
90.
Background: Bovine bone mineral (BBM) is extensively used as a filler material in periodontal reconstructive surgery of intrabony defects. Data are mostly available on the combined use of BBM with other biomaterials. The aim of this study is to evaluate healing after open‐flap debridement (OF) of intrabony periodontal defects alone or with adjunct treatment with BBM. Methods: After initial treatment, 32 patients with 32 intrabony periodontal defects participated in the study. Full‐thickness flaps were raised and root surfaces and defects were debrided. Patients were then randomly assigned to treatment groups, either OF alone or combined with defect fill with BBM, and followed in a strict postoperative maintenance care program for 12 months. Results: At 12 months, a mean ± SE gingival recession of 1.1 ± 0.3 mm in OF and 0.9 ± 0.4 mm in BBM occurred. Probing depth reduction was 4.0 ± 0.5 mm in OF and 3.2 ± 0.7 mm in BBM. Gain in clinical attachment level was 2.8 ± 0.6 mm in OF and 2.3 ± 0.8 mm in BBM. Probing bone level was reduced by 2.7 ± 0.7 mm in OF and 1.8 ± 1.1 mm in BBM. None of the above parameters showed significant intergroup differences. In contrast, radiographic defect depth change was significantly greater in BBM (3.4 ± 2.3 mm) than in OF (1.9 ± 1.7 mm). Conclusions: Both treatments resulted in improved periodontal conditions. The adjunctive use of BBM in this study did not enhance the clinical result compared to OF alone.  相似文献   
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