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1.
ObjectivesTo test the applicability, accuracy, precision, and reproducibility of various 3D superimposition techniques for radiographic data, transformed to triangulated surface data.MethodsFive superimposition techniques (3P: three-point registration; AC: anterior cranial base; AC + F: anterior cranial base + foramen magnum; BZ: both zygomatic arches; 1Z: one zygomatic arch) were tested using eight pairs of pre-existing CT data (pre- and post-treatment). These were obtained from non-growing orthodontic patients treated with rapid maxillary expansion. All datasets were superimposed by three operators independently, who repeated the whole procedure one month later. Accuracy was assessed by the distance (D) between superimposed datasets on three form-stable anatomical areas, located on the anterior cranial base and the foramen magnum. Precision and reproducibility were assessed using the distances between models at four specific landmarks. Non parametric multivariate models and Bland-Altman difference plots were used for analyses.ResultsThere was no difference among operators or between time points on the accuracy of each superimposition technique (p>0.05). The AC + F technique was the most accurate (D<0.17 mm), as expected, followed by AC and BZ superimpositions that presented similar level of accuracy (D<0.5 mm). 3P and 1Z were the least accurate superimpositions (0.79<D<1.76 mm, p<0.005). Although there was no difference among operators or between time points on the precision of each superimposition technique (p>0.05), the detected structural changes differed significantly between different techniques (p<0.05). Bland-Altman difference plots showed that BZ superimposition was comparable to AC, though it presented slightly higher random error.ConclusionsSuperimposition of 3D datasets using surface models created from voxel data can provide accurate, precise, and reproducible results, offering also high efficiency and increased post-processing capabilities. In the present study population, the BZ superimposition was comparable to AC, with the added advantage of being applicable to scans with a smaller field of view.  相似文献   

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ObjectivesTo identify which children with acute otitis media are at risk of poor outcome and to assess benefit from antibiotics in these children.DesignSecondary analysis of randomised controlled trial cohort.SettingPrimary care.Participants315 children aged 6 months to 10 years.InterventionImmediate or delayed (taken after 72 hours if necessary) antibiotics.ResultsDistress by day three was more likely in children with high temperature (adjusted odds ratio 4.5, 95% confidence interval 2.3 to 9.0), vomiting (2.6,1.3 to 5.0), and cough (2.0, 1.1 to 3.8) on day one. Night disturbance by day three was more likely with high temperature 2.4 (1.2 to 4.8), vomiting (2.1,1.1 to 4.0), cough (2.3,1.3 to 4.2), and ear discharge (2.1, 1.2 to 3.9). Among the children with high temperature or vomiting, distress by day three was less likely with immediate antibiotics (32% for immediate v 53% for delayed, χ2=4.0; P=0.045, number needed to treat 5) as was night disturbance (26% v 59%, χ2=9.3; P=0.002; number needed to treat 3). In children without higher temperature or vomiting, immediate antibiotics made little difference to distress by day three (15% v 19%, χ2=0.74; P=0.39) or night disturbance (20% v 27%, χ2=1.6; P=0.20). Addition of cough did not significantly improve prediction of benefit.ConclusionIn children with otitis media but without fever and vomiting antibiotic treatment has little benefit and a poor outcome is unlikely.

What is already known on this topic

Most children with otitis media will not benefit symptomatically from immediate use of antibioticsIt is unclear which children are more likely to benefit from antibiotics and which features predict poor outcome

What this study adds

Children with high temperature or vomiting were more likely to be distressed or have night disturbance three days after seeing the doctorChildren with high temperature or vomiting were more likely to benefit from antibiotics, although it is still reasonable to wait 24-48 hours as many children will settle anywayChildren without high temperature or vomiting were unlikely to have poor outcome and unlikely to benefit from immediate antibiotics  相似文献   

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ObjectiveTo improve the efficacy of closed reduction and wire guiding during intramedullary nail internal fixation in femoral shaft fractures.MethodsA novel instrument was designed and manufactured. Sixty-eight patients were enrolled from February 2011 to December 2013. The instrument designed was used during the operation in the experimental group, but not in the control group.ResultsAll patients exhibited fracture union, excluding 1 patient in the experimental group and 2 in the control group who had non-union; all of whom achieved fracture union with reoperation. There were no statistically significant differences in operative blood loss or duration of hospital stay between the groups (P > 0.05). The operative time, frequency of wire drilling, and number of open reduction cases, were significantly smaller in the experimental group than in the control group (P < 0.05).ConclusionFemoral shaft fractures are difficult to reduce using general methods; the novel instrument showed high clinical value and proved effective and safe in assisting with closed reduction and intramedullary nail fixation for femoral shaft fractures.

Trial Registration

ChiCTR ChiCTR-ICR-15007335  相似文献   

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目的:探讨空心钉张力带钢丝联合应用内固定在髌骨骨折患者中的临床疗效及安全性。方法:收集于我院就诊的150例髌骨骨折患者,随机分为实验组和对照组,各75例。对照组患者行钢丝环扎内固定术,实验组患者给予空心钉张力带钢丝内固定术。观察并比较两组患者骨折愈合时间、手术时间、临床治疗优良率以及患者的并发症的发生情况。结果:与对照组相比,实验组患者的骨折愈合时间显著缩短,但手术时间较长,治疗优良率较高,并发症发生率较低,差异均具有统计学意义(P0.05)。结论:与钢丝环扎内固定术比较,空心钉张力带钢丝联合应用治疗髌骨骨折的临床疗效较好,安全性更高。  相似文献   

6.

Background

A recent study of obesity in Swedish men found that polymorphisms in the type 3 adenylyl cyclase (AC3) are associated with obesity, suggesting the interesting possibility that AC3 may play a role in weight control. Therefore, we examined the weight of AC3 mice over an extended period of time.

Methodology/Principal Findings

We discovered that AC3−/− mice become obese as they age. Adult male AC3−/− mice are about 40% heavier than wild type male mice while female AC3−/− are 70% heavier. The additional weight of AC3−/− mice is due to increased fat mass and larger adipocytes. Before the onset of obesity, young AC3−/− mice exhibit reduced physical activity, increased food consumption, and leptin insensitivity. Surprisingly, the obesity of AC3−/− mice is not due to a loss of AC3 from white adipose and a decrease in lipolysis.

Conclusions/Significance

We conclude that mice lacking AC3 exhibit obesity that is apparently caused by low locomotor activity, hyperphagia, and leptin insensitivity. The presence of AC3 in primary cilia of neurons of the hypothalamus suggests that cAMP signals generated by AC3 in the hypothalamus may play a critical role in regulation of body weight.  相似文献   

7.
The Legionella colonization frequency at 385 Greek hotel hot and cold water distribution systems was 20.8%. Legionella contamination was associated with the presence of an oil heater (odds ratio [OR] = 2.04, 95% confidence interval [CI] = 1.12 to 3.70), with the sample temperature (OR = 0.26, 95% CI = 0.1 to 0.5), with seasonal operation (OR = 3.23, 95% CI = 1.52 to 6.87), and with the presence of an independent disinfection system (OR = 0.30, 95% CI = 0.15 to 0.62). The same water temperatures, free-chlorine levels, and pHs differently affect the survival of various Legionella spp.  相似文献   

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IntroductionImmune checkpoint inhibition has shifted treatment paradigms in non-small cell lung cancer (NSCLC). Conflicting results have been reported regarding the immune infiltrate and programmed death-ligand 1 (PD-L1) as a prognostic marker. We correlated the immune infiltrate and PD-L1 expression with clinicopathologic characteristics in a cohort of resected NSCLC.MethodsA tissue microarray was constructed using triplicate cores from consecutive resected NSCLC. Immunohistochemistry was performed for CD8, FOXP3 and PD-L1. Strong PD-L1 expression was predefined as greater than 50% tumor cell positivity. Matched nodal samples were assessed for concordance of PD-L1 expression.ResultsOf 522 patients, 346 were node-negative (N0), 72 N1 and 109 N2; 265 were adenocarcinomas (AC), 182 squamous cell cancers (SCC) and 75 other. Strong PD-L1 expression was found in 24% cases. In the overall cohort, PD-L1 expression was not associated with survival. In patients with N2 disease, strong PD-L1 expression was associated with significantly improved disease-free (DFS) and overall survival (OS) in multivariate analysis (HR 0.49, 95%CI 0.36–0.94, p = 0.031; HR 0.46, 95%CI 0.26–0.80, p = 0.006). In this resected cohort only 5% harboured EGFR mutations, whereas 19% harboured KRAS and 23% other. KRAS mutated tumors were more likely to highly express PD-L1 compared to EGFR (22% vs 3%). A stromal CD8 infiltrate was associated with significantly improved DFS in SCC (HR 0.70, 95%CI 0.50–0.97, p = 0.034), but not AC, whereas FOXP3 was not prognostic. Matched nodal specimens (N = 53) were highly concordant for PD-L1 expression (89%).ConclusionPD-L1 expression was not prognostic in the overall cohort. PD-L1 expression in primary tumor and matched nodal specimens were highly concordant. The observed survival benefit in N2 disease requires confirmation.  相似文献   

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Mammalian KIF3AC contains two distinct motor polypeptides and is best known for its role in organelle transport in neurons. Our recent studies showed that KIF3AC is as processive as conventional kinesin-1, suggesting that their ATPase mechanochemistry may be similar. However, the presence of two different motor polypeptides in KIF3AC implies that there must be a cellular advantage for the KIF3AC heterodimer. The hypothesis tested was whether there is an intrinsic bias within KIF3AC such that either KIF3A or KIF3C initiates the processive run. To pursue these experiments, a mechanistic approach was used to compare the pre-steady-state kinetics of KIF3AC to the kinetics of homodimeric KIF3AA and KIF3CC. The results indicate that microtubule collision at 11.4 μm−1 s−1 coupled with ADP release at 78 s−1 are fast steps for homodimeric KIF3AA. In contrast, KIF3CC exhibits much slower microtubule association at 2.1 μm−1 s−1 and ADP release at 8 s−1. For KIF3AC, microtubule association at 6.6 μm−1 s−1 and ADP release at 51 s−1 are intermediate between the constants for KIF3AA and KIF3CC. These results indicate that either KIF3A or KIF3C can initiate the processive run. Surprisingly, the kinetics of the initial event of microtubule collision followed by ADP release for KIF3AC is not equivalent to 1:1 mixtures of KIF3AA plus KIF3CC homodimers at the same motor concentration. These results reveal that the intermolecular communication within the KIF3AC heterodimer modulates entry into the processive run regardless of whether the run is initiated by the KIF3A or KIF3C motor domain.  相似文献   

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Summary

The effect of 1-methyladenine (1-MeA) on adenylate cyclase (AC) basal activity and on preliminary stimulated AC activity was investigated in oocyte membrane preparations of the starfish Aphelasterias japonica. 1-MeA inhibited the membrane-bound AC activity both after its addition to intact oocytes and in cell-free experiments. GTP did not affect AC activity but it intensified the inhibitory effect of 1-MeA on AC activity. Sodium fluoride (F″) stimulated the oocyte AC (8 fold), while 1-MeA significantly reduced F″-stimulated activity. Manganese (MnCl2, 5mM) stimulated AC (150 fold), but 1-MeA did not reduce Mn2+-stimulated activity. However, Mn2+-stimulated AC activity was inhibited by 1-MeA in the presence of MgCl2. Forskolin stimulated AC activity (7 fold) and 1-MeA had no effect on AC. Thus, the inhibitory effect of 1-MeA on stimulated AC activity is displayed only after stimulation of the regulatory AC subunit. We suggest that 1-MeA inhibits the oocyte AC acting via inhibitory regulatory Gi protein of AC.  相似文献   

13.
In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO2) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO2 enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms-1 average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO2 had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO2. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming for much of the time.  相似文献   

14.

Background

Fetal heart rate (FHR) variability is an indirect index of fetal autonomic nervous system (ANS) integrity. FHR variability analysis in labor fails to detect early hypoxia and acidemia. Phase-rectified signal averaging (PRSA) is a new method of complex biological signals analysis that is more resistant to non-stationarities, signal loss and artifacts. It quantifies the average cardiac acceleration and deceleration (AC/DC) capacity.

Objective

The aims of the study were: (1) to investigate AC/DC in ovine fetuses exposed to acute hypoxic-acidemic insult; (2) to explore the relation between AC/DC and acid-base balance; and (3) to evaluate the influence of FHR decelerations and specific PRSA parameters on AC/DC computation.

Methods

Repetitive umbilical cord occlusions (UCOs) were applied in 9 pregnant near-term sheep to obtain three phases of MILD, MODERATE, and SEVERE hypoxic-acidemic insult. Acid-base balance was sampled and fetal ECGs continuously recorded. AC/DC were calculated: (1) for a spectrum of T values (T = 1÷50 beats; the parameter limits the range of oscillations detected by PRSA); (2) on entire series of fetal RR intervals or on “stable” series that excluded FHR decelerations caused by UCOs.

Results

AC and DC progressively increased with UCOs phases (MILD vs. MODERATE and MODERATE vs. SEVERE, p<0.05 for DC  = 2–5, and AC  = 1–3). The time evolution of AC/DC correlated to acid-base balance (0.4<<0.9, p<0.05) with the highest for . PRSA was not independent from FHR decelerations caused by UCOs.

Conclusions

This is the first in-vivo evaluation of PRSA on FHR analysis. In the presence of acute hypoxic-acidemia we found increasing values of AC/DC suggesting an activation of ANS. This correlation was strongest on time scale dominated by parasympathetic modulations. We identified the best performing parameters (), and found that AC/DC computation is not independent from FHR decelerations. These findings establish the basis for future clinical studies.  相似文献   

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目的:探讨两种不同的手术方式(钛制空心钉结合张力带内固定手术)对髌骨骨折患者的临床疗效和安全性比较。方法:选择2016年6月-2017年10月治疗的髌骨骨折患者72例作为对象,使用随机数字表,随机分为对照组(n=36)和观察组(n=36)。对照组给予常规的克氏针张力带内固定进行手术,观察组则使用空心钉张力带进行固定。治疗后对患者效果进行统计和评估,比较两组患者的术后骨折的愈合时间,功能恢复(最大屈曲角度),髌骨评分以及并发症等指标。结果:根据不同的治疗方式后,观察组(空心钉张力带固定组)在骨折的愈合时间,功能恢复,髌骨评分以及并发症等比较指标中较对照组均有显著优势,其结果具备统计学意义(P<0.05)。结论:将钛制空心钉结合张力带内固定手术用于髌骨骨折与传统的克氏针张力带固定方法相比较,具有操作简便,骨折愈合率高,功能恢复确实,并发症发生率低等诸多优点,值得在临床中进一步推广应用。  相似文献   

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BackgroundActivated carbon (AC) is a carbonaceous material derived from carbonization and activation of carbon-containing compounds at high temperature and has a large surface area, providing it with excellent adsorption properties. Human exposure to ACs via ingestion is increasing and, unfortunately, there is little to no evidence related to its level of toxicityMaterials and methodsActivated carbon of powdered date kernels from Al-Baha city in Saudi Arabia were used to treat rats and cell lines (HepG2 and HCT-116). Toxicity, microbiological tests and biochemical analyses were carried out to investigate biological activity of both commercially available AC (CAC), pharmaceutical AC (PAC) and AC from date palm kernels (AAC)ResultsNone of the ACs showed activity on Staphylococcus aureus, Bacillus subtilis, Protius mirabilis and Escherichia coli. AAC showed the most cytotoxic effect on both HCT-116 and HepG2 cell lines after 24 h, with IC50 of 48.7 ± 17.2 µg/ml and 51 ± 6.24 µg/ml respectively. Rats treated with AAC for 48 h showed no impairment of hepatic and renal functions, unlike those exposed to CAC and PAC. Similarly, AAC-exposed rats did not show oxidative stress in both the liver and kidneys while CAC and PAC exposure resulted in depletion of CAT, GPx, SOD and GSH in both organs. L-arginase and α-fucosidase expression were also induced by both PAC and CAC while α-fucosidase levels were unaffected in AAC-exposed ratsConclusionAAC appears to be biologically safe compared with PAC and CAC due to its antioxidant activities and non-effect on both hepatic and renal functions.  相似文献   

18.
BackgroundClimate change may significantly affect human health. The possible effects of high ambient temperature must be better understood, particularly in terms of certain diseases’ sensitivity to heat (as reflected in relative risks [RR]) and the consequent disease burden (number or fraction of cases attributable to high temperatures), in order to manage the threat.PurposeThis study investigated the number of deaths attributable to abnormally high ambient temperatures in Seoul, South Korea, for a wide range of diseases.MethodThe relationship between mortality and daily maximum temperature using a generalized linear model was analyzed. The threshold temperature was defined as the 90th percentile of maximum daily temperatures. Deaths were classified according to ICD-10 codes, and for each disease, the RR and attributable fractions were determined. Using these fractions, the total number of deaths attributable to daily maximum temperatures above the threshold value, from 1992 to 2009, was calculated. Data analyses were conducted in 2012–2013.ResultsHeat-attributable deaths accounted for 3,177 of the 271,633 deaths from all causes. Neurological (RR 1.07; 95% CI, 1.04–1.11) and mental and behavioral disorders (RR 1.04; 95% CI, 1.01–1.07) had relatively high increases in the RR of mortality. The most heat-sensitive diseases (those with the highest RRs) were not the diseases that caused the largest number of deaths attributable to high temperatures.ConclusionThis study estimated RRs and deaths attributable to high ambient temperature for a wide variety of diseases. Prevention-related policies must account for both particular vulnerabilities (heat-sensitive diseases with high RRs) and the major causes of the heat mortality burden (common conditions less sensitive to high temperatures).  相似文献   

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目的:比较克氏针内固定术与钢板内固定术在锁骨骨折患者中的临床疗效和安全性。方法:收集我院收治的的70例锁骨骨折患者,随机分为克氏针内固定组和钢板内固定组,每组35例。克氏针内固定组患者给予克氏针内固定术,钢板内固定组患者采用钢板内固定术,观察并比较两组患者手术时间、住院时间,术中出血量,畸形愈合、延迟愈合、肩关节疼痛、切口感染、钢板断裂等并发症的发生率以及临床疗效。结果:与钢板内固定组相比,克氏针内固定组患者的手术时间以及住院时间较短,术中出血量较少,但并发症发生率较高,临床治疗优良率较低,差异具有统计学意义(P0.05)。结论:钢板内固定组患者的临床效果较好,并发症发生率较低,但克氏针内固定方法在手术时间、住院时间,术中出血量方面具有一定的优势。  相似文献   

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摘要 目的:对支气管哮喘(BA)患者和慢性阻塞性肺疾病(COPD)患者诱导痰黏蛋白5AC(MUC5AC)、炎症细胞和炎症因子水平进行比较以及相关性分析,评估MUC5AC鉴别BA和COPD的价值。方法:选取2018年9月至2019年9月来海南医学院第一附属医院就诊的BA稳定期患者(BA组)60例,同期COPD稳定期(COPD组)患者60例。诱导痰法采样并处理痰液,检测诱导痰MUC5AC、炎症细胞中性粒细胞(Neu)、巨噬细胞(Mac)、嗜酸性粒细胞(Eos)、淋巴细胞(Lym)、炎症因子血管内皮生长因子(VEGF)、细胞间黏附分子-1(ICAM-1)、白介素13(IL-13)和白介素17(IL-17)水平,通过Pearson相关分析对MUC5AC水平与Neu、Mac、Eos、Lym、VEGF、ICAM-1、IL-13、IL-17的关系进行分析。此外,采用受试者工作特征(ROC)曲线分析MUC5AC、炎症细胞及炎症因子鉴别诊断BA及COPD的效能。结果:COPD组诱导痰MUC5AC水平高于BA组,差异有统计学意义(P<0.05);COPD组诱导痰Mac和Eos水平均低于BA组,COPD组诱导痰Neu水平高于BA组,差异均有统计学意义(P<0.05);COPD组诱导痰VEGF、ICAM-1、IL-13和IL-17水平均低于BA组,差异均有统计学意义(P<0.05);Pearson相关分析结果显示,诱导痰MUC5AC与炎症细胞Mac、Eos和炎症因子VEGF、ICAM-1、IL-13和IL-17呈负相关(P<0.05),与炎症细胞Neu呈正相关(P<0.05)。经ROC曲线分析可得:诱导痰MUC5AC鉴别BA和COPD的曲线下面积、灵敏度、特异度以及约登指数均高于炎症细胞Neu、Mac、Eos以及炎症因子VEGF、ICAM-1、IL-13、IL-17。结论:COPD患者诱导痰MUC5AC水平高于BA患者,MUC5AC与炎症细胞和炎症因子有关,MUC5AC的检测有助于鉴别BA或COPD,其有望作为临床BA或COPD的监测指标和治疗靶点。  相似文献   

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