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21.
Andrew X. Li Benjamin J. Resio Maureen E. Canavan Marianna Papageorge Daniel J. Boffa Justin D. Blasberg 《Journal of thoracic disease》2021,13(6):3409
BackgroundPrimary lung sarcoma (PLS) represents a rare form of lung cancer with outcomes that are poorly defined by small datasets. We sought to characterize clinical and pathological characteristics and associated survival within the surgically managed subgroup of these unusual pulmonary malignancies.MethodsWe performed a retrospective analysis of the National Cancer Database (NCDB), which was queried for cases of surgically managed PLS diagnosed between 2004–2014. Adjusted mortality was evaluated in a multivariable Cox proportional hazards model and compared to surgically manage non-small cell lung cancer (NSCLC) patients from the same time period.ResultsA total of 695 patients with surgically managed PLS were identified with 37 different histologic subtypes. The mean age of diagnosis was 57.7 years (range, 18–90 years). A majority of patients underwent surgical resection alone (64.3%) with an estimated 5-year overall survival (OS) of 51%. The multivariable Cox model identified increasing age, Charlson-Deyo score ≥2, high tumor grade, tumor size >5 cm, positive margins, and positive lymph nodes to be associated with higher risk for mortality (P<0.05). Compared to 101,428 surgically managed patients with adenocarcinoma, PLS patients were younger with fewer comorbidities but had larger tumors, higher grade tumors, and were more likely node negative (P<0.001). Surgery with adjuvant chemotherapy was associated with worse survival than surgery alone (HR 1.41, 95% CI: 1.05–1.88). The extent of parenchymal resection (lobar vs. sublobar) was not predictive for survival. Five-year OS was lower for patients with PLS (44%) than adenocarcinoma (53.6%, P<0.001).ConclusionsThe survival of surgically managed PLS is reasonable and impacted by tumor attributes and the completeness of surgical resection. Further study to define the role of multimodal therapy is indicated. 相似文献
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Grazyna Debska‐Vielhaber PhD Judith Machts MSc Verena Dannhardt‐Stieger MD Helmut Feistner MD Andreas Oldag MD Michael Goertler MD Susanne Petri MD Katja Kollewe MD Siegfried Kropf PhD Frank Schreiber MSc Hans‐Jochen Heinze MD Reinhard Dengler MD Peter J. Nestor MD Stefan Vielhaber MD 《Muscle & nerve》2015,51(5):669-675
Introduction: In this study we sought to determine the cross‐sectional area (CSA) of peripheral nerves in patients with distinct subtypes of amyotrophic lateral sclerosis (ALS). Methods: Ulnar and median nerve ultrasound was performed in 78 ALS patients [classic, n = 21; upper motor neuron dominant (UMND), n = 14; lower motor neuron dominant (LMND), n = 20; bulbar, n = 15; primary lateral sclerosis (PLS), n = 8] and 18 matched healthy controls. Results: Compared with controls, ALS patients had significant, distally pronounced reductions of ulnar CSA (forearm/wrist level) across all disease groups, except for PLS. Median nerve CSA (forearm/wrist level) did not differ between controls and ALS. Conclusion: Ulnar nerve ultrasound in ALS subgroups revealed significant differences in distal CSA values, which suggests it has value as a marker of LMN involvement. Its potential was particularly evident in the UMND and PLS groups, which can be hard to separate clinically, yet their accurate separation has major prognostic implications. Muscle Nerve 51 :669–675, 2015 相似文献
23.
该文建立了同步测定延胡索中盐酸黄连碱、海罂粟碱、脱氢紫堇碱、延胡索乙素和延胡索甲素5种生物碱成分的近红外光谱定量模型。首先采用高效液相色谱结合紫外检测法测定延胡索中上述5种成分的化学值,然后采用傅里叶变换近红外光谱技术并结合偏最小二乘法(PLS) 建立、优化模型,采用校正模型的相关系数(r) 、校正均方根误差(RMSEC)、内部交叉验证均方根误差(RMSECV)和预测模型的相关系数(r)和预测均方根误差(RMSEP)对校正模型进行评价。所建立的定量校正模型中盐酸黄连碱、海罂粟碱、脱氢紫堇碱、延胡索乙素和延胡索甲素的r分别为0.941 0,0.972 7,0.964 3, 0.978 1,0.979 9; RMSEC分别为0.006 7,0.003 5,0.005 9,0.002 8,0.005 9; RMSECV 分别为0.015,0.011,0.020,0.010,0.022。预测模型中上述5种成分的相关系数r分别为0.916 6, 0.942 9,0.943 6,0.916 7,0.914 5; RMSEP 分别为0.009,0.006 6,0.007 5,0.006 9,0.011。该研究所建立的近红外定量模型稳定性较好,预测结果较准确,可望用于延胡索药材中5种主要生物碱成分的同步快速测定。 相似文献
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25.
SVEN HELLBERG LENNART ERIKSSON J
RGEN JONSSON FREDRIK LINDGREN MICHAEL SJ
STR
M BERT SKAGERBERG SVANTE WOLD PETER ANDREWS 《Chemical biology & drug design》1991,37(5):414-424
The information contents in previously published peptide sets was compared with smaller sets of peptides selected according to statistical designs. It was found that minimum analogue peptide sets (MAPS) constructed by factorial or fractional factorial designs in physicochemical properties contained substantial structure-activity information. Although five to six times smaller than the originally published peptide sets the MAPS resulted in QSAR models able to predict biological activity. The QSARs derived from a MAPS of nine dipeptides, and from a set of 58 dipeptides inhibiting angiotensin converting enzyme were compared and found to be of equal strength. Furthermore, for a set of bitter tasting dipeptides it was found that an incomplete MAPS of 10 dipeptides gave just as good a model as the model based on a set of 48 dipeptides. By comparison other non-designed sets of peptides gave QSARs with poor predictive power. It was also demonstrated how MAPS centered on a lead peptide can be constructed as to specifically explore the physicochemical and biological properties in the vicinity of the lead. It was concluded that small information-rich peptide sets MAPS can be constructed on the basis of statistical designs with principal properties of amino acids as design variables. 相似文献
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27.
介绍了偏最小二乘法在分光光度法中同时测定复方药物的原理。用该法对克感敏片中三种成分非那西汀、氨基比林和咖啡因的含量进行了同时测定,所得平均回收率为100.2±0.4%,99.6±0.6%和100.3±0.7%(置信度为95%)。 相似文献
28.
结合统计回归与神经网络的优点,使用基于神经网络的非线性部分最小二乘回归法,建立了醋酸乙烯生产装置催化剂活性的非参数模型,模型的精度高且计算量较小。实际应用证明了方法的有效性。 相似文献
29.
The activity of single neurons in the mesencephalic locomotor region (MLR) was recorded extracellularly in cats during spontaneous locomotion on a treadmill. Although stimulation of the MLR is required to induce locomotion on a treadmill after a precollicular-postmamillary brain stem transection in the cat, spontaneous locomotion may occur after a precollicular-premamillary transection. The activity of flexor and extensor muscles of each limb also was recorded by EMG. Nearly 50% of the MLR neurons exhibited rhythmic firing patterns during locomotion. In about one-half of those cells, unit firing patterns could be correlated with the EMG activity in one or more muscles by using spike-triggered averaging. Single MLR neurons were found to be correlated to EMG activity in a single limb, and others were related to the EMG from muscles in two limbs or in all four limbs. Passive movement or stoppage of the limb(s) did not abolish rhythmicity in these neurons. In addition, somatosensory stimulation did not appear to affect the firing patterns of MLR neurons. Averaged EMGs of correlated forelimb muscles revealed a postspike mean latency of 7.1 ms. These measurements agreed well with reports of a 1- to 1.5-ms delay in MLR projections to reticulospinal neurons and a 5- to 6-ms delay (postspike) in reticulospinal activity correlated to EMGs during locomotion. These findings suggest that (a) MLR neurons are rhythmically active during locomotion, (b) the activity of MLR neurons can be correlated with that of EMGs in one or more limbs, (c) rhythmicity in MLR neurons may be independent of phasic sensory input, and (d) the downstream influence of the MLR may be relayed, at least in part, via reticulospinal neurons. 相似文献
30.