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排序方式: 共有755条查询结果,搜索用时 15 毫秒
1.
Rian M. Hasson Kayla A. Fay Joseph D. Phillips Timothy M. Millington David J. Finley 《American journal of surgery》2021,221(4):725-730
BackgroundRural populations face many health disadvantages compared to urban areas. There is a critical need to better understand the current lung cancer screening landscape in these communities to identify targeted areas to improve the impact of this proven tool.MethodsData from the County Health Rankings of New Hampshire and Vermont was reviewed for population density, distribution of adult smokers, and level of education compared to the distribution of Lung Cancer Screening Facilities throughout these two states.ResultsScreening programs in southern counties of Vermont with lower levels of education have decreased access. In New Hampshire, there are no programs within 30 miles of the areas with the largest distribution of smokers, and decreased access in some areas with the lowest levels of education.ConclusionsImproving equitable access to high-quality screening services in rural regions and the creation of targeted interventions to address decreased access in areas of high tobacco use and low education is vital to decreasing the incidence of latestage presentations of lung cancer within these populations. 相似文献
2.
3.
目的 探索大动物低剂量全身照射的适宜剂量 ,以便评价低剂量全身照射应用于临床的可能性。方法 食蟹猴 32只随机分为 4组 ,用γ射线 (吸收剂量率为 0 175mGy min)分别照射0、30、5 0和 75mGy。分别在环磷酰胺处理前、后 ,亦即照射前和照射后 1、2、8、33和 5 0周检测淋巴细胞亚群、免疫球蛋白及自然肿瘤红细胞花环试验 (NTERT)。结果 结果显示白细胞释放细胞因子尤其是CD1 6 参与免疫调控 ,出现时间 剂量的反应 ;体液免疫中以IgA升高为特征 ,照射后第 8周 5 0和75mGy 2个剂量组与对照组相比差异有显著性 (P <0 0 5 ) ;NTERT结果显示 ,在照射后第 2周 ,第 1、2、3组分别与第 4组相比差异有显著性 (P <0 0 5 ) ,但第 1组分别与第 2、3组相比差异无显著性。结论 γ射线单次低剂量全身照射对免疫功能低下模型的食蟹猴红、白细胞免疫功能有增强其免疫功能的作用。 相似文献
4.
The use of 3D surface fitting for robust polyp detection and classification in CT colonography 总被引:3,自引:0,他引:3
In this paper we describe the development of a computationally efficient computer-aided detection (CAD) algorithm based on the evaluation of the surface morphology that is employed for the detection of colonic polyps in computed tomography (CT) colonography. Initial polyp candidate voxels were detected using the surface normal intersection values. These candidate voxels were clustered using the normal direction, convexity test, region growing and Gaussian distribution. The local colonic surface was classified as polyp or fold using a feature normalized nearest neighborhood classifier. The main merit of this paper is the methodology applied to select the robust features derived from the colon surface that have a high discriminative power for polyp/fold classification. The devised polyp detection scheme entails a low computational overhead (typically takes 2.20 min per dataset) and shows 100% sensitivity for phantom polyps greater than 5 mm. It also shows 100% sensitivity for real polyps larger than 10 mm and 91.67% sensitivity for polyps between 5 to 10 mm with an average of 4.5 false positives per dataset. The experimental data indicates that the proposed CAD polyp detection scheme outperforms other techniques that identify the polyps using features that sample the colon surface curvature especially when applied to low-dose datasets. 相似文献
5.
Prof. Dr. F. A. Spengel G. Küffer H. Stiegler 《Journal of molecular medicine (Berlin, Germany)》1993,71(4):323-326
Summary The efficacy and safety of recombinant tissue-type plasminogen activator (rt-PA) was evaluated in 46 patients with thrombembolic arterial occlusions in leg arteries. rt-PA was given over 1–4 h with a maximum dose of 18 mg. The effect of rt-PA treatment was determined as patency of the occluded arteries in 44 different patients 14 days after treatment. In 41 patients at least one artery was recanalized (93%) by rt-PA, and in almost half of these patients (48%) no residual stenosis were detected after the lytic treatment. A slight residual stenosis was detected in 29% of the patients and a severe residual stenosis in 21%. An additional treatment with percutaneous transluminal angioplasty was performed in 23 of the 44 patients and successful in 21 (91%). In 8 patients an addition catheter-embolectomy was performed. No difference in patency rate was detected between patients with thrombotic and those with embolic occlusions. The age of the occlusion influenced the patency rate; occlusions under the age of 5 weeks showed a patency rate of 96% compared to 82% in older occlusions. The length of the occlusion did not have any influence on the outcome of the rt-PA treatment. From the results of this open study we conclude that a dose of up to 18 mg of rt-PA is both safe and effective in the treatment of thromboembolic occlusions in leg arteries.Abbreviations rt-PA
recombinant tissue-type plasminogen activator
- GGT
gamma-glutamyltransferase
- SGOT
aspartate aminotransferase
- SGPT
alanine aminotransferase
- LDH
lactate dehydrogenase
- PTA
percutaneous transluminal angioplasty
Dedicated to Prof. Dr. N. Zöllner on the occasion of his 70th birthday 相似文献
6.
Objective and design: The present study examined effectiveness of low-dose doxycycline (LDD) in combination with nonsurgical therapy on gingival
crevicular fluid (GCF) tissue plasminogen activator (t-PA) levels and clinical parameters in chronic periodontitis (CP) a
over 12-month period.
Methods: GCF samples were collected, probing depth (PD), clinical attachment level (CAL), gingival index (GI) and plaque index were
recorded at baseline, 3, 6, 9 and 12 months. CP patients (n = 65) were randomized to LDD or placebo groups. LDD group received
LDD (20 mg) b.i.d for 3-months plus and root planing (SRP), while placebo group was given placebo capsules b.i.d for 3-months
plus SRP. GCF t-PA levels were determined by ELISA. Friedman, Wilcoxon and Mann-Whitney test was used for statistical analysis.
Results: Significant improvement was observed in all clinical parameters in both groups over 12-month period (p < 0.01). LDD group
had lower PD, CAL and GI scores than placebo group at 6, 9 and 12-months (p < 0.05). GCF t-PA levels reduced in both groups
over 12-month period (p < 0.01). LDD group had lower GCF t-PA levels than placebo group at 6 and 9-months (p < 0.05).
Conclusions: These results provide additional information about usefulness of LDD therapy as an adjunct to nonsurgical therapy in long-term
management of periodontitis.
Received 8 May 2006; returned for revision 13 June 2006; accepted by J. Di Battista 12 July 2006 相似文献
7.
Friedrich Gönner Ralf Baumgartner Daniel Schüpbach M. C. G. Merlo 《Psychopharmacology》1999,144(4):416-418
Neuroleptic malignant syndrome (NMS) is a rare but potentially fatal side-effect of antipsychotic drug therapy, especially
of dopamine receptor antagonists. As a dose relationship has been postulated, low dose neuroleptization would be expected
to help to avoid this side-effect. In contrast, we report on a 21-year-old female following low dose fluphenazine treatment
with 2.5 mg/day. The patient recovered from NMS after 3 days of dantrolene administration. Eventually, remission from psychotic
symptoms was achieved with clozapine. At 8-month follow-up, psychopathology remained stable and there were no more signs of
NMS.
Received: 8 July 1998 / Final version: 6 November 1998 相似文献
8.
Reduction of epileptiform activity in response to low-dose clonazepam in children with epilepsy: a randomized double-blind study 总被引:4,自引:0,他引:4
PURPOSE: To evaluate the effect of low-dose clonazepam (CZP) on the amount of epileptiform activity in children with focal and generalized epilepsy. METHODS: In a single-blind pilot study, followed by a double-blind, placebo-controlled, randomized, crossover study, 15 children with epilepsy were evaluated by using 24-h long-term EEG recordings during baseline days and days after injections of placebo and CZP. The drug was given as a single i.m. injection of 0.02 mg/kg BW. Blood samples were obtained regularly for analysis of plasma concentrations of CZP. The number of epileptiform discharges was determined during corresponding periods with the individual child in the same state of alertness, the same real time of day, and with concomitant antiepileptic drugs (AEDs) unchanged. RESULTS: In the double-blind study, low-dose CZP produced a highly significant (p = 0.0015) decrease in the amount of epileptiform activity (mean, -69% vs. placebo, -2%) obtained during periods when median plasma concentrations ranged from 18 to <14 nM. The maximal plasma level (median, 24 nM) was reached before the start of the analysis periods. The pilot study showed reductions of epileptiform discharges within the same range as the double-blind study. In the children with daily seizures, a parallel decrease in seizures and the number of epileptiform discharges was seen after the administration of CZP. CONCLUSIONS: Our data demonstrate a significant reduction of epileptiform discharges on long-term EEGs after a single low dose of CZP with concomitant low plasma levels, which were considerably lower than the doses and plasma levels usually recommended. A concomitant reduction of seizures also was seen. 相似文献
9.
目的观察低浓度罗哌卡因颈丛麻醉在锁骨骨折手术中的应用.方法选颈丛阻滞麻醉,在c4横突处穿刺,给予0.25%罗哌卡因,分别在深丛7mL、浅丛15mL,共22mL注入.并与同样方法注入0.15%地卡因和1.00%利多卡因混合液22mL(加1200000肾上腺素)作比较.结果麻醉效果,观察组有效率95.6%,对照组有效率95.4%,二组无明显差异.副作用,观察组明显少于对照组,有显著差异(P<0.05).结论低浓度罗哌卡因进行颈丛麻醉效果好,副作用轻,与其他方法相比,该方法较好. 相似文献
10.
《European journal of radiology》2014,83(12):2268-2276
PurposeTo evaluate the effects of adaptive iterative dose reduction using 3D processing (AIDR 3D) for quantification of two measures of emphysema: percentage of low-attenuation volume (LAV%) and size distribution of low-attenuation lung regions.Method and materials: Fifty-two patients who underwent standard-dose (SDCT) and low-dose CT (LDCT) were included. SDCT without AIDR 3D, LDCT without AIDR 3D, and LDCT with AIDR 3D were used for emphysema quantification. First, LAV% was computed at 10 thresholds from −990 to −900 HU. Next, at the same thresholds, linear regression on a log–log plot was used to compute the power law exponent (D) for the cumulative frequency-size distribution of low-attenuation lung regions. Bland–Altman analysis was used to assess whether AIDR 3D improved agreement between LDCT and SDCT for emphysema quantification of LAV% and D.ResultsThe mean relative differences in LAV% between LDCT without AIDR 3D and SDCT were 3.73%–88.18% and between LDCT with AIDR 3D and SDCT were −6.61% to 0.406%. The mean relative differences in D between LDCT without AIDR 3D and SDCT were 8.22%–19.11% and between LDCT with AIDR 3D and SDCT were 1.82%–4.79%. AIDR 3D improved agreement between LDCT and SDCT at thresholds from −930 to −990 HU for LAV% and at all thresholds for D.ConclusionAIDR 3D improved the consistency between LDCT and SDCT for emphysema quantification of LAV% and D. 相似文献