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排序方式: 共有1162条查询结果,搜索用时 17 毫秒
1.
Screening colonoscopy for early detection and prevention of colorectal cancer (CRC) is mostly used inefficiently. Here, we assessed the potential of an innovative approach to colonoscopy-based screening, by use of a single, low threshold fecal immunochemical test (FIT) as a “gateopener” for screening colonoscopy. Using COSIMO, a validated simulation model, we modeled scenarios including either direct invitation to screening colonoscopy or an alternative approach involving mailing a single (“gateopener”) FIT along with an invitation to colonoscopy contingent on a FIT value above a low threshold yielding a 50% positivity rate (ie, every other pretest will be positive). Under plausible assumptions on screening offer adherence, we found that such “gateopener screening” (use of screening colonoscopy contingent on a positive, low threshold gateopener FIT) approximately doubled cancer detection rates vs conventional screening. In those spared from screening colonoscopy due to a negative gateopener FIT pretest, numbers needed to screen were 10-times higher vs those for individuals with a positive FIT, peaking in >2000 and >3800 (hypothetically) needed colonoscopies to detect one case of cancer in men and women, respectively. Gateopener screening resulted in 42%-51% and 59%-65% more prevented CRC cases and deaths, respectively. In summary, by directing colonoscopy capacities to those most likely to benefit, offering screening colonoscopy contingent on a “gateopener” low-threshold FIT would substantially enhance efficiency of colonoscopy screening.  相似文献   
2.
Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie - Beim Zahnwechsel gibt es nicht nur eine Trias, sondern eine Vielfalt von pathologischen Abläufen. Den letztlich...  相似文献   
3.
BACKGROUND: This report describes a novel technique for fabricating retrievable implant-supported titanium (Ti) prostheses in patients requiring a comprehensive treatment plan involving the combined efforts of maxillofacial surgery and implant prosthodontics. METHODS: Following bone graft reconstructive surgery and implant placement prosthetic treatment was initiated by inserting ITI-Octa abutments. An impression was made, and a framework was fabricated by fusing Ti-cast frameworks to prefabricated titanium copings by laser-welding. This was followed by veneering or fabrication of a removable denture with Ti metal re-enforcement. RESULTS: Favourable clinical results have been achieved using these screw-retained Ti implant-supported restorations for patients treated with reconstructive bone graft-surgery, with clinical observation periods ranging from three to four years. CONCLUSIONS: The present observations suggest that these screw-retained implant-supported Ti prostheses may be a meaningful contribution to implant prosthodontics, facilitating retrievable restorations of optimum biocompatibility, good marginal precision and with a good esthetic result. However, controlled clinical studies are needed to establish the long-term serviceability of these Ti restorations.  相似文献   
4.
目的:观察视神经损伤动物模型在损伤后和不同时期视神经管减压后视觉诱发电位的变化,了解创伤性视神经损伤的手术时机与疗效的关系。方法:实验于2005-03/05在解放军南京军区南京总医院动物实验中心完成。①实验分组:30只新西兰白兔随机分为正常对照组、术后2d减压组、术后7d减压组、术后14d减压组、术后不减压组,每组6只。②造模:除正常对照组外,其余各组在视神经孔中塞入一细端为2mm直径的圆锥软硅胶,阻塞视神经孔,造成视神经的挤压伤。③指标检测:采用图形翻转视觉诱发电位检测损伤前、损伤后1h、减压前1h、减压后2周视功能变化,记录NPN曲线主波(P波)的绝对潜伏期、绝对波幅。正常对照组仅采集一组数据作为对照。结果:30只实验动物均进入结果分析。①正常对照组家兔图形翻转视觉诱发电位检查均引出典型NPN波型曲线,视神经挤压伤后1hNPN波形低阔扁平,P波潜伏期延长,波幅降低。②P波潜伏期:术后2d减压组减压后短于减压前[(71.25±8.51),(86.47±14.28)ms,P<0.05];术后7d减压组减压前后比较差异无显著性(P>0.05);术后14d减压组减压后明显长于减压前[(158.73±15.16),(116.35±17.13)ms,P<0.05]。术后2d减压组和术后7d减压组短于术后不减压组(P<0.01)。术后7,14d减压组和术后不减压组明显长于正常对照组(P<0.01)。③P波波幅:术后2d减压组减压后高于减压前[(5.25±0.78),(4.42±0.42)μV,P<0.05]。术后2d减压组减压后低于术后7d减压组、术后14d减压组(P<0.01),术后14d减压组低于术后7d减压组(P<0.05);术后7d减压组、术后14d减压组、术后不减压组低于正常对照组(P<0.01)。结论:神经元继发性损伤是视功能进行性下降的重要原因,视神经减压术有利于减轻视神经间接损伤,较早期(损伤后48h以内)减压可阻止轴突继发性损伤,避免视功能进一步下降,并在一定程度上逆转视功能的损害。  相似文献   
5.
Current evidence on the association between smoking and colorectal cancer (CRC) prognosis after diagnosis is heterogeneous and few have investigated dose‐response effects or outcomes other than overall survival. Therefore, the association of smoking status and intensity with several prognostic outcomes was evaluated in a large population‐based cohort of CRC patients; 3,130 patients with incident CRC, diagnosed between 2003 and 2010, were interviewed on sociodemographic factors, smoking behavior, medication and comorbidities. Tumor characteristics were collected from medical records. Vital status, recurrence and cause of death were documented for a median follow‐up time of 4.9 years. Using Cox proportional hazards regression, associations between smoking characteristics and overall, CRC‐specific, non‐CRC related, recurrence‐free and disease‐free survival were evaluated. Among stage I–III patients, being a smoker at diagnosis and smoking ≥15 cigarettes/day were associated with lower recurrence‐free (adjusted hazard ratios (aHR): 1.29; 95% confidence interval (CI): 0.93–1.79 and aHR: 1.31; 95%‐CI: 0.92–1.87) and disease‐free survival (aHR: 1.26; 95%‐CI: 0.95–1.67 and aHR: 1.29; 95%‐CI: 0.94–1.77). Smoking was associated with decreased survival in stage I–III smokers with pack years ≥20 (Overall survival: aHR: 1.40; 95%‐CI: 1.01–1.95), in colon cancer cases (Overall survival: aHR: 1.51; 95%‐CI: 1.05–2.17) and men (Recurrence‐free survival: aHR: 1.51; 95%‐CI: 1.09–2.10; disease‐free survival: aHR: 1.49; 95%‐CI: 1.12–1.97), whereas no associations were seen among women, stage IV or rectal cancer patients. The observed patterns support the existence of adverse effects of smoking on CRC prognosis among nonmetastatic CRC patients. The potential to enhance prognosis of CRC patients by promotion of smoking cessation, embedded in tertiary prevention programs warrants careful evaluation in future investigations.  相似文献   
6.
Colorectal cancer guidelines recommend adjuvant chemotherapy in stage II disease when less than 12 lymph nodes are assessed. The recommendation bases on previous studies showing an association of a low lymph node count and adverse outcome. Compared to current standards, however, the quality of lymph node examination in the studies was low. We, therefore, investigated the prognostic role of <12 lymph nodes in cancers diagnosed adherent to current quality measures. Stage I–IV colorectal cancers from 1,899 patients enrolled into a population‐based cohort study were investigated for the prognostic impact of a lymph node count <12. The stage specific share of patients diagnosed with ≥12 nodes (stage I–IV: 62, 85, 85, 78%, respectively) was used to compare lymph node examination quality to other studies. We found no impact of a lymph node count <12 on overall, cancer‐specific or recurrence‐free survival for any tumour stage. Compared to studies reporting an adverse prognostic impact of a low lymph node count in stages II and III the stage‐specific shares of patients with ≥12 nodes were markedly higher in this study (85% vs. 24–58% in previous analyses) and this correlated with increased rates of stage III compared to stage II cancers. In conclusion our data indicate, that the previously reported effect of a low lymph node count on the patients' outcomes is eliminated by improved lymph node examination quality and thus question the general applicability of a 12 lymph node cut off for adjuvant chemotherapy decision making in stage II disease.  相似文献   
7.
Blood coagulation and fibrinolysis in arteriosclerosis]   总被引:3,自引:0,他引:3  
Thrombus formation at the site of atherosclerotic lesions, especially on a ruptured plaque, plays a central role in the "atherothrombosis" hypothesis. An activation of the hemostasis and a disturbed fibrinolysis are known. These alterations are especially marked in patients with acute coronary syndromes. In stable coronary artery disease, fibrinogen is elevated. Furthermore, minor alterations of the contact phase factor VII and consecutively of the thrombin system are detectable depending on the study population. Thrombin generation and activation become marked in patients with unstable angina pectoris or acute myocardial infarction. Possible reasons for this activation are an activation of the contact phase factor XII system and the release of tissue factor both from the ruptured plaque and from stimulated monocytes. The fibrinolytic system is markedly altered already in patients with stable coronary heart disease. Increased levels of tissue-type plasminogen activator and of urokinase-type plasminogen activator/receptor are measurable in atheromas. Tissue-type plasminogen activator mass concentration is systemically elevated already at early stages of atherosclerosis. Especially in patients with increased risk for acute coronary syndromes, the plasminogen activator inhibitor activity is significantly increased. Furthermore, a hypercoagulative state with increased d-dimer levels and plasmin-antiplasmin complexes can be measured. The alterations of hemostasis and especially of fibrinolysis are detectable for prolonged time period and persist much longer than the clinical symptoms of the patients. The increased plasminogen activator inhibitor activity is associated with the metabolic syndrome and constitutes an (in part genetically determined) disturbance in patients with stable or unstable coronary heart disease. However, the large intra- und interobserver as well as diurnal variability of this marker limits its use as a routine measure for risk stratification in patients. Alterations of the hemostasis and disturbances of fibrinolysis are detectable during the chronic as well as the acute phase of atherosclerosis. These changes are best documented for coronary heart disease, whereas less data are available for other manifestations of atherosclerosis. The use of newly developed molecular markers for single reaction steps of pathways instead of global functional tests and of new molecular biological methods did considerably improve the detailed knowledge on the pathomechanisms of the development of atherosclerosis, making the development of targeted therapies, e.g., against receptors possible. Future studies will investigate the quantitative impact of the various activated pathways (cause or reaction) and the effects of interventions on these pathomechanisms in patients with acute coronary syndromes. Studies will have to focus especially on the meaning of polymorphisms, early changes in the development of atherosclerosis and interactions with inflammatory processes.  相似文献   
8.
The optimal reperfusion strategy in elderly patients with ST-segment elevation myocardial infarction (STEMI) remains a topic of debate. Therefore, we investigated in the MITRA PLUS registry clinical outcome variables in 5455 patients aged>70 years and STEMI on admission at hospitals without the facilities of coronary catheterization and PCI. Outcome was compared after thrombolysis, transfer to PCI and after no reperfusion therapy. Data of this registry in STEMI patients older than 70 years, who were transferred to another hospital for PCI, showed a strong trend for lower in-hospital mortality rates compared with a strategy with sole fibrinolysis and significantly lower in hospital death rates compared with a conservative treatment without (medical or mechanical) reperfusion. Additionally, the PCI group also had a reduced incidence of the combined events: death, myocardial reinfarction, stroke in comparison with both other infarct groups. Data of the presented MITRA PLUS registry in STEMI patients older than 70 years support data of several other studies, that patients with STEMI benefit from a transfer to primary PCI even after a time delay of symptom onset to hospital admission of more than 2 h compared with a strategy using sole fibrinolytic therapy.  相似文献   
9.
10.
The oculoauriculofrontonasal syndrome (OAFNS) is a rare craniofacial malformation which causes massive disturbance of physiological craniofacial development and can be associated with other malformations; however, cognitive development can be unaffected. It is characterized by vertical median facial clefting in combination with bilateral otomandibular dysplasia. Hypertelorism, orbital dystopia, mandibular and hearing deficiency are key features. The etiology remains uncertain and sporadic occurrence is likely. Interindividual variance in expression must be expected requiring highly individualized age and growth-related treatment concepts in order to achieve a less obtrusive appearance.  相似文献   
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