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排序方式: 共有2085条查询结果,搜索用时 31 毫秒
31.
Rijbroek A Vermeulen EG Wisselink W Rauwerda JA 《The Journal of cardiovascular surgery》2000,41(5):753-758
BACKGROUND: The aim of this study was to analyse the results of infragenual arterial revascularisation using semiclosed endarterectomy of the superficial femoral artery combined with a short venous bypass in patients with critical leg ischemia and insufficient venous material for a straightforward femorocrural reconstruction. METHODS: From December 1990 through December 1998 thirty patients were studied (22 males and 8 females; mean age 65 years, range 31-92 years). The mean follow-up was 26 months (range 1-96 months). Cumulative primary patency and limb salvage rates were calculated according to life-table analysis. RESULTS: The cumulative primary patency was 60.3% at 1 year and 48.4% at 3 years. The limb salvage rate was 68.6% at 1 and at 3 years. CONCLUSIONS: In patients with limb-threatening ischemia and lack of venous material for a straightforward venous femorocrural bypass, semi-closed endarterectomy of the superficial femoral artery combined with a short popliteo-crural bypass provides a good alternative. 相似文献
32.
Tumor lymphangiogenesis in inflammatory breast carcinoma: a histomorphometric study. 总被引:11,自引:0,他引:11
Ilse Van der Auwera Gert G Van den Eynden Cecile G Colpaert Steven J Van Laere Peter van Dam Eric A Van Marck Luc Y Dirix Peter B Vermeulen 《Clinical cancer research》2005,11(21):7637-7642
PURPOSE: At the time of diagnosis, metastatic dissemination of tumor cells via the lymphatic system has occurred in nearly all patients with inflammatory breast cancer (IBC). The objective of this study was twofold: (a) to determine which is the most suitable marker of lymph vessels in primary breast tumors and (b) to compare histomorphometric lymph vessel variables in IBC and non-IBC. EXPERIMENTAL DESIGN: Serial sections of 10 IBCs and 10 non-IBCs were immunostained for D2-40, LYVE-1, podoplanin, and PROX-1. Relative lymph vessel area, lymph vessel perimeters, and counts and lymphatic endothelial cell proliferation (LECP) were then measured in D2-40/Ki-67 double-immunostained sections of 10 normal breast tissues, 29 IBCs, and 56 non-IBCs. RESULTS: D2-40 was the most suitable antibody for staining peritumoral and intratumoral lymph vessels. D2-40-stained intratumoral lymph vessels were present in 80% of non-IBCs and 82.8% of IBCs (P = 0.76). In non-IBC, lymph vessels located in the tumor parenchyma were smaller and less numerous than those at the tumor periphery (P < 0.0001) whereas in IBC, intratumoral and peritumoral variables were not significantly different. The mean relative tumor area occupied by lymph vessels was larger in IBC than in non-IBC (P = 0.01). LECP at the tumor periphery was higher in IBC than in non-IBC: median LECP was 5.74% in IBC versus 1.83% in non-IBC (P = 0.005). CONCLUSIONS: The high LECP in IBC suggests that lymphangiogenesis contributes to the extensive lymphatic spread of IBC. 相似文献
33.
James M Hoffman Sylvia Thomley Lee Vermeulen Kelly M Smith 《American journal of health-system pharmacy》2004,61(23):2528-2533
PURPOSE: A survey of U.S. academic medical centers (AMCs) was conducted to identify the most important and challenging issues in pharmacy residency training. METHODS: A questionnaire addressing program characteristics and residency training concerns was sent electronically to pharmacy directors at 130 AMCs that are members or associate members of the University HealthSystem Consortium (UHC). Residency coordinators for both pharmacy practice and specialized programs were asked to complete the questionnaire, with input from other pharmacists involved in the residency program. Respondents were asked to rate the importance and degree of challenge for all issues on a 5-point Likert scale, where 1 = least important or least challenging and 5 = most important or most challenging. RESULTS: Responses were received from hospitals representing over 60% of all residency positions offered by UHC member hospitals. Recruitment was rated the most important issue (mean importance score, 4.8) facing residency programs in AMCs, but with over 85% of budgeted positions filled, programs appear to be successful in overcoming this concern. The most challenging issue (mean challenge score, 4.2) was compliance with the evaluation and documentation elements of the ASHP Residency Learning System (RLS), a system often used to meet requirements for pharmacy practice residency accreditation. The completion of resident research requirements was ranked as both an important and a challenging issue (mean importance score, 4.5; mean challenge score, 3.9). CONCLUSION: A survey of AMCs showed that they offered a wide variety of pharmacy residency programs and filled most budgeted resident positions. Resident recruitment, the RLS, and research requirements are the most important and challenging residency concerns facing the respondents. 相似文献
34.
Yufei Dai Dianzhi Ren Bryan A. Bassig Roel Vermeulen Wei Hu Yong Niu Huawei Duan Meng Ye Tao Meng Jun Xu Ping Bin Meili Shen Jufang Yang Wei Fu Kees Meliefste Debra Silverman Nathaniel Rothman Qing Lan Yuxin Zheng 《Environmental and molecular mutagenesis》2018,59(2):144-150
The International Agency for Research on Cancer has classified diesel engine exhaust (DEE) as a human lung carcinogen. Given that inflammation is suspected to be an important underlying mechanism of lung carcinogenesis, we evaluated the relationship between DEE exposure and the inflammatory response using data from a cross‐sectional molecular epidemiology study of 41 diesel engine testing workers and 46 unexposed controls. Repeated personal exposure measurements of PM2.5 and other DEE constituents were taken for the diesel engine testing workers before blood collection. Serum levels of six inflammatory biomarkers including interleukin (IL)‐1, IL‐6, IL‐8, tumor necrosis factor (TNF)‐α, macrophage inflammatory protein (MIP)‐1β, and monocyte chemotactic protein (MCP)‐1 were analyzed in all subjects. Compared to unexposed controls, concentrations of MIP‐1β were significantly reduced by ~37% in DEE exposed workers (P < 0.001) and showed a strong decreasing trend with increasing PM2.5 concentrations in all subjects (Ptrend < 0.001) as well as in exposed subjects only (Ptrend = 0.001). Levels of IL‐8 and MIP‐1β were significantly lower in workers in the highest exposure tertile of PM2.5 (>397 µg/m3) compared to unexposed controls. Further, significant inverse exposure‐response relationships for IL‐8 and MCP‐1 were also found in relation to increasing PM2.5 levels among the DEE exposed workers. Given that IL‐8, MIP‐1β, and MCP‐1 are chemokines that play important roles in recruitment of immunocompetent cells for immune defense and tumor cell clearance, the observed lower levels of these markers with increasing PM2.5 exposure may provide insight into the mechanism by which DEE promotes lung cancer. Environ. Mol. Mutagen. 59:144–150, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
35.
The potential role of lung microbiota in lung cancer attributed to household coal burning exposures 下载免费PDF全文
Nathaniel Rothman Thomas Rohan Wei Hu Jun Xu Roel Vermeulen Xingzhou He James Robert White Guoping Wu Fusheng Wei Qing Lan 《Environmental and molecular mutagenesis》2014,55(8):643-651
Bacteria influence site‐specific disease etiology and the host's ability to metabolize xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs). Lung cancer in Xuanwei, China has been attributed to PAH‐rich household air pollution from burning coal. This study seeks to explore the role of lung microbiota in lung cancer among never smoking Xuanwei women and how coal burning may influence these associations. DNA from sputum and buccal samples of never smoking lung cancer cases (n = 8, in duplicate) and controls (n = 8, in duplicate) in two Xuanwei villages was extracted using a multi‐step enzymatic and physical lysis, followed by a standardized clean‐up. V1‐V2 regions of 16S rRNA genes were PCR‐amplified. Purified amplicons were sequenced by 454 FLX Titanium pyrosequencing and high‐quality sequences were evaluated for diversity and taxonomic membership. Bacterial diversity among cases and controls was similar in buccal samples (P = 0.46), but significantly different in sputum samples (P = 0.038). In sputum, Granulicatella (6.1 vs. 2.0%; P = 0.0016), Abiotrophia (1.5 vs. 0.085%; P = 0.0036), and Streptococcus (40.1 vs. 19.8%; P = 0.0142) were enriched in cases compared with controls. Sputum samples had on average 488.25 species‐level OTUs in the flora of cases who used smoky coal (PAH‐rich) compared with 352.5 OTUs among cases who used smokeless coal (PAH‐poor; P = 0.047). These differences were explained by the Bacilli species (Streptococcus infantis and Streptococcus anginosus). Our small study suggests that never smoking lung cancer cases have differing sputum microbiota than controls. Further, bacteria found in sputum may be influenced by environmental exposures associated with the type of coal burned in the home. Environ. Mol. Mutagen. 55:643–651, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
36.
37.
DM Lyaruu L Vermeulen N Stienen TJ Bervoets PK Denbesten AL Bronckers 《Caries research》2012,46(6):575-580
Excessive intake of fluoride (F) by young children results in the formation of enamel subsurface porosities and pits, called enamel fluorosis. In this study, we used a single high dose of F administered to hamster pups to determine the stage of ameloblasts most affected by F and whether pit formation was related to F-related sub-ameloblastic cyst formation. Hamster pups received a single subcutaneous injection of either 20 mg or 40 mg NaF/kg body weight, were sacrificed 24 h later, and the number of cysts formed in the first molars were counted. Other pups were sacrificed 8 days after F injection, when the first molars had just erupted, to score for enamel defects. All F-injected pups formed enamel defects in the upper half of the cusps in a dose-dependent way. After injection of 20 mg NaF/kg, an average of 2.5 white spots per molar was found but no pits. At 40 mg NaF/kg, almost 4.5 spots per molar were counted as well as 2 pits per molar. The defects in erupted enamel were located in the upper half of the cusps, sites where cysts had formed at the transition stage of ameloblast differentiation. These results suggest that transitional ameloblasts, located between secretory- and maturation-stage ameloblasts, are most sensitive to the effects of a single high dose of F. F-induced cysts formed earlier at the pre-secretory stage were not correlated to either white spots or enamel pits, suggesting that damaged ameloblasts overlying a F-induced cyst regenerate and continue to form enamel. 相似文献
38.
Venkatesh Pilla Reddy Magdalena Kozielska Rik de Greef An Vermeulen Johannes H. Proost 《Journal of pharmacokinetics and pharmacodynamics》2013,40(3):377-388
High and variable placebo effect (PE) within and among clinical trials can substantially affect conclusions about the efficacy of new drugs in the treatment of schizophrenia and other neuropsychiatric disorders. In recent years, it has become increasingly difficult to prove drug efficacy against placebo, and one of the reasons is that the placebo response has increased over recent years. The increased placebo response over the years is partly explained by unidentified parallel interventions, patient factors, issues with trial designs, and regional variability or demographic differences. In addition, a nocebo effect, which is undesirable effects a subject manifests after receiving placebo, e.g. extrapyramidal side effects, in placebo arms of antipsychotic trials could also influence the PE and clinical trial outcomes. Placebo effects (PEs) are a natural phenomenon and cannot be avoided completely in clinical trials. However, accounting for the PE via mixed effects modelling approaches could reduce bias in quantifying the overall effect size of the drug treatment. This review article focuses on the PE and its impact on schizophrenia clinical trial outcomes. The authors briefly describe the factors that lead to high and variable PE. Next, pharmacometric approaches to account for the PE and dropouts in schizophrenia clinical trials are described. Finally, some points are provided that could be considered while designing and optimizing antipsychotic trials via simulation approaches. 相似文献
39.
Amina Amadou Heinz Freisling Mazda Jenab Konstantinos K. Tsilidis Antonia Trichopoulou Paolo Boffetta Bethany Van Guelpen Olatz Mokoroa Tom Wilsgaard Frank Kee Ben Schttker Jos M. Ordez-Mena Satu Mnnist Stefan Sderberg Roel C. H. Vermeulen J. Ramn Quirs Linda M. Liao Rashmi Sinha Kari Kuulasmaa Hermann Brenner Isabelle Romieu 《British journal of cancer》2021,124(11):1882
Background We investigated whether associations between prevalent diabetes and cancer risk are pertinent to older adults and whether associations differ across subgroups of age, body weight status or levels of physical activity.Methods We harmonised data from seven prospective cohort studies of older individuals in Europe and the United States participating in the CHANCES consortium. Cox proportional hazard regression was used to estimate the associations of prevalent diabetes with cancer risk (all cancers combined, and for colorectum, prostate and breast). We calculated summary risk estimates across cohorts using pooled analysis and random-effects meta-analysis.Results A total of 667,916 individuals were included with an overall median (P25–P75) age at recruitment of 62.3 (57–67) years. During a median follow-up time of 10.5 years, 114,404 total cancer cases were ascertained. Diabetes was not associated with the risk of all cancers combined (hazard ratio (HR) = 0.94; 95% confidence interval (CI): 0.86–1.04; I2 = 63.3%). Diabetes was positively associated with colorectal cancer risk in men (HR = 1.17; 95% CI: 1.08–1.26; I2 = 0%) and a similar HR in women (1.13; 95% CI: 0.82–1.56; I2 = 46%), but with a confidence interval including the null. Diabetes was inversely associated with prostate cancer risk (HR = 0.81; 95% CI: 0.77–0.85; I2 = 0%), but not with postmenopausal breast cancer (HR = 0.96; 95% CI: 0.89–1.03; I2 = 0%). In exploratory subgroup analyses, diabetes was inversely associated with prostate cancer risk only in men with overweight or obesity.Conclusions Prevalent diabetes was positively associated with colorectal cancer risk and inversely associated with prostate cancer risk in older Europeans and Americans.Subject terms: Risk factors, Cancer epidemiology 相似文献
40.