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61.
嗜神经侵袭是肿瘤通过神经扩散与转移的一种独特的生物学行为,与复发、转移、预后密切相关。随着研究的不断深入,人们普遍认识到嗜神经侵袭的临床意义。但由于头颈部肿瘤发病率相对较低,不同解剖部位、不同病理类型嗜神经发生率各不相同,故缺乏高级别的循证医学证据。目前嗜神经侵袭的病理学机制尚未完全阐明,也无针对神经侵犯的特异性治疗手段,因此头颈部肿瘤嗜神经侵袭的治疗对于临床医师是一个巨大的挑战。本文就头颈部恶性肿瘤中嗜神经侵袭的临床诊治现状做一综述。 相似文献
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目的 利用MRI技术连续采集头颈部肿瘤患者吞咽时图像,观察并测量软腭、舌、喉的运动规律及最大活动度。方法 随机选取2018年7月-10月在中国医学科学院肿瘤医院接受调强放疗的原发头颈部恶性肿瘤20例患者,其中男17例、女3例,中位年龄58.5岁(28~78岁)。20例患者中鼻咽癌7例,口腔癌3例,口咽癌5例,下咽癌3例,鼻腔鼻旁窦2例。根据AJCC第八版分期Ⅰ-Ⅱ期患者2例,Ⅲ期8例,Ⅳ期10例。结果 吞咽时软腭向上移动移动距离为(1.06±0.31) cm且服从正态分布,向后移动距离为(0.83±0.24) cm且近似正态分布。舌体向后移动距离为(0.77±0.22) cm,且服从正态分布。含压舌板行图像采集患者舌上移位移为0,无压舌板患者舌体中位上移距离为1.23 cm (0.59~1.41 cm)。喉向上移动距离为(1.14±0.22) cm且服从正态分布,向前移动的中位距离为0.4 cm (0.27~0.90 cm)。结论 吞咽运动有可能发生于头颈部肿瘤患者放疗过程中,并引起大体肿瘤体积(GTV)及周围正常组织移动;因此在制定放疗计划时应注意GTV至PGTV的个体化外放距离,以保证肿瘤处方剂量。 相似文献
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IntroductionMuch remains to be learned regarding the epistemology and utility of guidelines and clinical prediction rules (CPR), as well as the extent to which knowledge about risk at a population level might be pertinent to any given patient in terms of case finding accuracy. In the current paper, we offer an empirical examination that juxtaposes population-based guidelines and CPR for sexual health decision-making.Materials and methodsWe analyzed electronic medical records from asymptomatic patient visits involving tests for chlamydia or gonorrhea between 2000 and 2012 at nine publicly funded STI clinics in British Columbia to compare the case-finding accuracy for infection risk under two scenarios: (1) if the population had been screened using the Public Health Agency of Canada (PHAC) screening guidelines for chlamydia and gonorrhea; or (2) if the population has been screened using a CPR. Performance metrics evaluated included the area under the ROC curve (AUC).ResultsIn total, 35,818 individuals met the study inclusion criteria. The overall infection rate was 3.0%. Using the PHAC guidelines, the discriminatory performance of using any versus no risk factors and counts of risk factors were: AUC = 0.55, 95% CI: 0.54–0.56 and AUC = 0.64, 95% CI: 0.63–0.66, respectively. The model used to derive the CPR demonstrated good discrimination (AUC = 0.73, 95% CI: 0.71–0.74).ConclusionsThe current paper provides empirical evidence that demonstrates that population-based guidelines may not necessarily be a perfect fit for application at the individual level. Thus, we recommend risk estimation algorithms for use in sexual health services and programs. 相似文献
66.
《Biomaterials》2015
Podophyllotoxin (PPT) exhibited significant activity against P-glycoprotein mediated multidrug resistant (MDR) tumor cell lines; however, due to its poor solubility and high toxicity, PPT cannot be dosed systemically, preventing its clinical use for MDR cancer. We developed a nanoparticle dosage form of PPT by covalently conjugating PPT and polyethylene glycol (PEG) with acetylated carboxymethyl cellulose (CMC-Ac) using one-pot esterification chemistry. The polymer conjugates self-assembled into nanoparticles (NPs) of variable sizes (20–120 nm) depending on the PPT-to-PEG molar ratio (2–20). The conjugate with a low PPT/PEG molar ratio of 2 yielded NPs with a mean diameter of 20 nm and released PPT at ∼5%/day in serum, while conjugates with increased PPT/PEG ratios (5 and 20) produced bigger particles (30 nm and 120 nm respectively) that displayed slower drug release (∼2.5%/day and ∼1%/day respectively). The 20 nm particles exhibited 2- to 5-fold enhanced cell killing potency and 5- to 20-fold increased tumor delivery compared to the larger NPs. The biodistribution of the 20 nm PPT-NPs was highly selective to the tumor with 8-fold higher accumulation than all other examined tissues, while the larger PPT-NPs (30 and 120 nm) exhibited increased liver uptake. Within the tumor, >90% of the 20 nm PPT-NPs penetrated to the hypovascular core, while the larger particles were largely restricted in the hypervascular periphery. The 20 nm PPT-NPs displayed significantly improved efficacy against MDR tumors in mice compared to the larger PPT-NPs, native PPT and the standard taxane chemotherapies, with minimal toxicity. 相似文献
67.
骨碎补是历代临床常用中药,具有疗伤止痛、补肾强骨、消风祛斑等功效。其主要含黄酮、苯丙素、三萜、酚酸及其苷等类化学成分,现代研究表明骨碎补具有抗骨质疏松、促进骨折愈合、促软骨再生、护牙健齿、保护肾功能、抗炎、防治中毒性耳聋、降血脂等多种生物活性,开发前景广阔。本文对近年来骨碎补的化学成分、药理作用及临床应用研究进行综述,以期为骨碎补的进一步深入系统的研究和开发利用提供依据。 相似文献
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ObjectiveThis study used a prospective cohort study to observe the effect of triple-negative breast cancer on the 2-year disease-free survival rate with or without “TCM formula”.MethodsFrom November 1 st, 2016, the first patient was enrolled in the cohort study. A total of 356 patients were enrolled on January 30, 2019. Among them, 154 cases were followed up for 2 years. During the follow-up, there were 6 cases of shedding, so 6 cases were affected. A total of 148 cases were included in the analysis, including 73 in the exposed group and 75 in the non-exposed group. The exposed group was given “TCM formula” on the basis of standardized treatment, and the non-exposed group was treated with simple triple-negative breast cancer. The two groups visited each of the three months. The interview included safety examination (hematology and imaging). The endpoint was the difference in 2-year invasive disease-free survival between the exposed and non-exposed groups and the safety of the “TCM formula”.ResultsThere were 6 cases of shedding during the experiment and the shedding rate was 3.9 %. The 2-year rate of invasive disease-free survival in the exposed team was 88.7 % and the non-exposed group was 82.5 %. Logistic multivariate regression analysis predicted that “TCM formula” could reduce the disease-related recurrence and metastasis rate by 11 % (OR = 0.89, 95 % CI 0.37−0.956, P<0.05). Through K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node stage N1 may be the benefit group of “TCM formula”(P<0.05). During the study, the incidence of total adverse events was 8.2 % in the exposed group, mainly manifested as stomach discomfort, diarrhea, and hepatocyte damage.Conclusion1. In the exposed group, the two-year rate of invasive disease-free survival increased by 6.2 % compared with the non-exposed group(P>0.05). 2. According to K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node metastasis to N1 may be potential beneficiaries of “TCM formula”. 3. “TCM Formula” is safe and tolerable to most patients. 相似文献
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Normal aging is associated with cognitive decline and underlying brain dysfunction. Previous studies concentrated less on brain network changes at a systems level. Our goal was to examine these age-related changes of fMRI-derived activation with a common network parcellation of the human brain function, offering a systems-neuroscience perspective of healthy aging. We conducted a series of meta-analyses on a total of 114 studies that included 2035 older adults and 1845 young adults. Voxels showing significant age-related changes in activation were then overlaid onto seven commonly referenced neuronal networks. Older adults present moderate cognitive decline in behavioral performance during fMRI scanning, and hypo-activate the visual network and hyper-activate both the frontoparietal control and default mode networks. The degree of increased activation in frontoparietal network was associated with behavioral performance in older adults. Age-related changes in activation present different network patterns across cognitive domains. The systems neuroscience approach used here may be useful for elucidating the underlying network mechanisms of various brain plasticity processes during healthy aging. 相似文献