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1.
近年来肿瘤免疫治疗迅速发展,极大地改善了许多实体瘤患者的预后。但并非所有实体瘤患者都能产生持久的反 应,且其疗效也受到免疫治疗相关不良反应的限制。目前,实体瘤内免疫治疗作为一种局部免疫治疗手段越来越受到关注。本 文首先介绍当前实体瘤的免疫治疗研究现状,分析了实体瘤内免疫治疗这一新兴治疗手段在减少药物的系统性暴露及其不良反 应、增强肿瘤免疫原性、克服肿瘤异质性等方面的显著优势,然后就目前可用于实体瘤内免疫治疗的药物及其应用进展进行了简 要地归纳,最后从疗效评价、具体实施等方面总结了实体瘤内免疫治疗所面临的挑战与对策,以期达到对实体瘤内免疫治疗理念 的推广和普及作用。  相似文献   
2.
目的 探讨基于人工智能学习CT密度定量对肺内孤立性亚实性及实性结节的良恶性诊断价值。 方法 回顾性分析延安大学附属医院2017年6月至2021年6月经手术后病理学检查证实的73例肺内孤立性亚实性及实性肺结节患者,利用人工智能肺结节辅助诊断分析软件对肺结节患者胸部CT进行定量分析。采用独立样本t检验或非参数检验比较两组患者CT密度定量参数的差异,进行单因素与多因素的二元logistic回归分析,绘制ROC曲线并计算曲线下面积(AUC),鉴别肺腺癌的独立危险因素。P<0.05为差异有统计学意义。 结果 肺亚实性及实性结节的大小(长、短径)及CT最大值差异均无统计学意义。CT平均值、CT最小值与CT值方差有统计学意义(P<0.05)。回归分析显示CT值方差是肺腺癌组患者独立影响因素(OR值=1.020,95%CI: 1.003~1.037),预测准确率80.4%。ROC曲线下面积AUC=0.812(95%CI: 0.680~0.943),临界值60.13,灵敏度78.6%,特异度78.6%。 结论 人工智能肺结节CT密度定量参数能够鉴别肺腺癌与肺内良性结节,CT值方差是敏感、客观的影像学定量指标。  相似文献   
3.
ObjectiveTo study the clinical features and identify unique renal neoplasia subtypes and their prognostic implications in individuals with tuberous sclerosis complex (TSC).Patients and MethodsThe Mayo Clinic nephrectomy registry included 37 patients with TSC diagnosed between 1970 and 2018. Four additional patients were identified from the pathology consultation and autopsy files. All available renal tumors were further characterized using immunohistochemistry and fluorescence in situ hybridization. Clinicopathologic features and follow-up were obtained from the medical record. The American Association for Cancer Research Project GENIE registry was accessed using cBioPortal for molecular profiling of angiomyolipoma (AML).ResultsA total of 276 renal tumors from 41 patients were analyzed. Renal tumors were classified into 9 distinct morphological subtypes, with AML predominating (238 [86%]). Interestingly, all these tumors acted in a benign fashion except one renal cell carcinoma with clear cells and fibromyomatous stroma and one epithelioid AML that metastasized. Molecular profiling studies revealed that epithelioid AMLs were enriched for alterations of TP53, RB1, and ATRX. Eight patients died of direct complications of TSC, including 3 of end-stage renal disease. To date, none have died of a renal epithelial neoplasm.ConclusionThe identification of unique renal neoplasia subtypes may provide important clues to establish a diagnosis of TSC, and in the somatic setting, this finding has important implications for accurate prognostication. These tumors tend to be indolent, and only 2 of 276 tumors in our study exhibited metastatic behavior. Our results support multidisciplinary management with a focus on preservation of renal function.  相似文献   
4.
Severe postnatal systemic infection is highly associated with persistent disturbances in brain development and neurobehavioral outcomes in survivors of preterm birth. However, the contribution of less severe but prolonged postnatal infection and inflammation to such disturbances is unclear. Further, the ability of modern imaging techniques to detect the underlying changes in cellular microstructure of the brain in these infants remains to be validated. We used high-field ex-vivo MRI, neurohistopathology, and behavioral tests in newborn rats to demonstrate that prolonged postnatal systemic inflammation causes subtle, persisting disturbances in brain development, with neurodevelopmental delays and mild motor impairments. Diffusion-tensor MRI and neurite orientation dispersion and density imaging (NODDI) revealed delayed maturation of neocortical and subcortical white matter microstructure. Analysis of pyramidal neurons showed that the cortical deficits involved impaired dendritic arborization and spine formation. Analysis of oligodendrocytes showed that the white matter deficits involved impaired oligodendrocyte maturation and axonal myelination. These findings indicate that prolonged postnatal inflammation, without severe infection, may critically contribute to the diffuse spectrum of brain pathology and subtle long-term disability in preterm infants, with a cellular mechanism involving oligodendrocyte and neuronal dysmaturation. NODDI may be useful for clinical detection of these microstructural deficits.  相似文献   
5.
张艳慧  丁玉  李淑荣 《中成药》2021,(2):302-307
目的制备熊果酸磷脂复合物纳米结构脂质载体,并考察其体内药动学。方法乳化?超声分散法制备熊果酸磷脂复合物纳米结构脂质载体,测定粒径、Zeta电位、包封率、载药量、体外释药。大鼠灌胃给药(12.5 mg/mL)后,于0.25、0.75、1、1.5、2、2.5、3、4、6、8、12 h采血,HPLC法测定熊果酸血药浓度,计算主要药动学参数。结果所得制剂呈类球形或球形,平均粒径、Zeta电位、包封率、载药量分别为(209.32±4.47)nm、-(10.82±0.42)mV、80.54%、3.57%;36 h内累积释放度低于70%,释药符合Weibull模型(R2=0.9906)。与原料药、磷脂复合物比较,纳米结构脂质载体tmax延长(P<0.05,P<0.01),Cmax、AUC0~t、AUC0~∞升高(P<0.01);与原料药比较,磷脂复合物、纳米结构脂质载体相对生物利用度分别增加至2.73、3.95倍。结论磷脂复合物纳米结构脂质载体可促进熊果酸体内吸收,提高其口服生物利用度。  相似文献   
6.
There could be two carcinogenetic pathways for lung adenocarcinoma (LADC): the nonsmokers’ pathway and the smokers’ pathway. This review article describes the two pathways with special reference to potential relationships between histological subtypes, malignant grades, and driver mutations. The lung is composed of two different tissue units, the terminal respiratory unit (TRU) and the central airway compartment (CAC). In the nonsmokers’ pathway, LADCs develop from the TRU, and their histological appearances change from lepidic to micropapillary during the progression process. In the smokers’ pathway, LADCs develop from either the TRU or the CAC, and their histological appearances vary among cases in the middle of the progression process, but they are likely converged to acinar/solid at the end. On a molecular genetic level, the nonsmokers’ pathway is mostly driven by EGFR mutations, whereas in the smokers’ pathway, approximately one-quarter of LADCs have KRAS mutations, but the other three-quarters have no known driver mutations. p53 mutations are an important factor triggering the progression of both pathways, with unique molecular alterations associated with each, such as MUC21 expression and chromosome 12p13-21 amplification in the nonsmokers’ pathway, and HNF4α expression and TTF1 mutations in the smokers’ pathway. However, investigation into the relationship between histological progression and genetic alterations is in its infancy. Tight cooperation between traditional histopathological examinations and recent molecular genetics can provide valuable insight to better understand the nature of LADCs.  相似文献   
7.
目的制备欧前胡素固体分散体,并考察其体内药动学。方法溶剂挥发法制备固体分散体后,检测欧前胡素存在状态,并测定溶解度、溶出率、累积溶出度。大鼠随机分为2组,分别灌胃给予欧前胡素及其固体分散体0??3%CMC?Na混悬液(25 mg/kg),于0.25、0.5、1、1.5、2、3、4、6、8、12 h采血,HPLC法测定欧前胡素血药浓度,计算主要药动学参数。结果欧前胡素以结晶型状态存在,制成固体分散体后转变为无定型状态,溶解度、溶出率、累积溶出度明显升高。与原料药比较,固体分散体tmax缩短(P<0.05),Cmax、AUC0-t、AUC0-∞升高(P<0.01),相对生物利用度增加至2??03倍。结论固体分散体可改善欧前胡素溶解度、溶出率、累积溶出度,促进其体内吸收。  相似文献   
8.
Background/ObjectivesWe aimed to examine therapeutic efficacy and prognosis prediction of autoimmune pancreatitis (AIP) using shear wave elastography (SWE) and shear wave dispersion (SWD) in transabdominal ultrasound (US).MethodsThe subjects were 23 patients with diffuse type 1 AIP who underwent SWE and SWD, and 34 controls with a normal pancreas. Elasticity and dispersion were defined as the pancreatic elastic modulus (PEM) and dispersion slope, respectively. PEM and dispersion slope were compared between AIP and control cases, and the short-term therapeutic effect and long-term prognosis were examined.ResultsPEM (30.9 vs. 6.6 kPa, P < 0.001) and dispersion slope (15.3 vs. 13.0 (m/sec)/kHz, P = 0.011) were significantly higher in AIP cases than in controls. Among the 17 AIP patients followed-up in two weeks after treatment, these parameters were 12.7 kPa and 10.5 (m/sec)/kHz with median decrease rate of 37.2% and 32.8%, respectively, which were significantly higher than the change in the size of pancreatic parenchyma (14.4%, P = 0.026). Fourteen of these subjects were followed up for >12 months, during which 2 had relapse; diabetes improved in 5 and worsened in 2; in 60% of cases, the pancreatic parenchyma was atrophied. The % change in PEM after two weeks was tended to be higher in non-atrophy cases.ConclusionSWE and SWD measurement in US may be useful for quantitative assessment of AIP and evaluation of short-term treatment efficacy.  相似文献   
9.
目的:观察稳心颗粒联合尼可地尔治疗缺血性心肌病合并房性心律失常患者的效果。方法:选取103例缺血性心肌病合并房性心律失常患者作为研究对象,以电脑随机数字表法将其分为研究组51例和对照组52例。两组均开展常规基础治疗,在此基础上,对照组采用尼可地尔治疗,研究组在对照组基础上联合稳心颗粒治疗,比较两组治疗前后心功能指标[左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)、左室射血分数(LVEF)]水平、P波最大时限、P波离散度、6 min步行试验(6MWT)距离和不良反应发生率。结果:治疗后,研究组LVEDD和LVESD水平均低于对照组,LVEF水平高于对照组,6MWT距离长于对照组,差异有统计学意义(P<0.05);治疗后,研究组P波最大时限和P波离散度均小于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:稳心颗粒联合尼可地尔治疗缺血性心肌病合并房性心律失常患者可改善心功能指标水平,延长6MWT距离,减小P波最大时限和P波离散度,效果优于单纯尼可地尔治疗。  相似文献   
10.
In this paper, we consider the numerics of the dispersion-managed Korteweg-de Vries (DM-KdV) equation for describing wave propagations in inhomogeneous media. The DM-KdV equation contains a variable dispersion map with discontinuity, which makes the solution non-smooth in time. We formally analyze the convergence order reduction problems of some popular numerical methods including finite difference and time-splitting for solving the DM-KdV equation, where a necessary constraint on the time step has been identified. Then, two exponential-type dispersion-map integrators up to second order accuracy are derived, which are efficiently incorporated with the Fourier pseudospectral discretization in space, and they can converge regardless of the discontinuity and the step size. Numerical comparisons show the advantage of the proposed methods with the application to solitary wave dynamics and extension to the fast & strong dispersion-management regime.  相似文献   
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