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1.
美国食品药品管理局(FDA)于2022年7月发布了"治疗等效性评价供企业用指导原则"(草案)。该指导原则阐明了FDA治疗等效性的标准以及治疗等效性编码系统,目的是准确评价仿制药与参比制剂的治疗等效性并通过治疗等效性代码,在"橙皮书"中迅速检索到治疗等效的仿制药。而中国目前尚无类似的指导原则,详细介绍FDA该指导原则主要内容,期望对中国加强仿制药的治疗等效性评价和加速完善和实施符合国情的治疗等效性编码系统有所帮助。  相似文献   
2.
BackgroundSinonasal mucosal melanoma (SNMM) is a rare tumour with a poor prognosis. The purpose of this study was to identify independent predictors of outcome in SNMM and to examine the expression of PD-L1 and the relationship between expression and clinicopathological characteristics.MethodsA total of 117 patients with SNMM were reviewed in the Department of Pathology of Beijing Tongren Hospital (115 cases) and Beijing Chuiyangliu Hospital (2 cases) from June 2007 to June 2018. We evaluated the expression of PD-L1 in SNMM and investigated whether there was an association between the expression of the marker and clinicopathological characteristics.ResultsSex, age, side, location, size, histological type, melanin particles, nuclear fission and tumour infiltrating lymphocytes (TILs) were not significantly related to survival. The median survival times at the T3, T4a, and T4b stages were 23, 19, and 6 months, respectively. The difference between overall survival (OS) and AJCC stages was statistically significant. The tumour cells (TCs) were PD-L1 positive in 14/117 (12.0%) cases, and tumour-associated immune cells (ICs) were PD-L1 positive in 23/117 (19.7%) cases. A statistically significant correlation was observed between the positive expression rate of PD-L1 in ICs and TILs grading; however, there was no significant correlation between the positive expression rate of PD-L1 in TCs and TILs grading.ConclusionThe AJCC stages were the only independent predictors of survival. There was no correlation between the positive expression rate of PD-L1 and OS. A statistically significant correlation was observed between the positive expression rate of PD-L1 in ICs and TILs grading.  相似文献   
3.
Nodular hyperplasia of the thyroid is a process whereby the gland experiences growth by nodular expansion of thyroid parenchyma. We have encountered 45 patients in whom the process was caused by the growth of well-defined and sharply circumscribed but unencapsulated nodules composed of oncocytic thyroid follicular cells. The lesions arose in 39 women and 6 men, aged 25–69 years (mean = 50.3 years). The surrounding thyroid parenchyma showed features of chronic lymphocytic thyroiditis. The nodules varied from microscopic to 5 cm and appeared to compress the surrounding thyroid parenchyma. Most of the lesions lacked a well-defined capsule. In 26 tumors, the nodules displayed a predominantly follicular pattern of growth; in 8 cases there were admixtures of follicular and trabecular patterns with focal solid areas devoid of follicles. Clinical follow-up in 39 patients ranging from 7 to 22 years (median = 16 years) showed no evidence of recurrence, metastasis, or malignant transformation. One patient died of unknown causes 15 years after the diagnosis, and another patient died 4 years after diagnosis from metastatic colonic adenocarcinoma. Oncocytic nodular hyperplasia is a benign process associated with chronic lymphocytic thyroiditis that should be distinguished from benign and malignant oncocytic (Hurthle cell) tumors of the thyroid.  相似文献   
4.
目的 以2017年某省食品安全监测大米中砷含量数据为例,探讨空间统计学方法在食品污染物分析中的应用价值。方法 采用空间点模式估计、核密度分析,全局以及局部自相关性分析等空间统计学方法,在县级空间尺度下,对某省大米中砷含量进行探索性空间数据分析。结果 空间点模式分布图显示,该省大米砷污染的空间分布比较分散,核密度分析结果显示污染热点区域主要在该省中东部地区。全局自相关Moran''s I指数值为0.11,有统计学意义,大米样品中砷污染呈现出低度空间聚集性。有1个"高-高"聚集区,2个典型的"低-低"聚集区。结论 空间统计学运用于食物污染物分布研究上,可以很好地可视化展示、识别污染分布规律、热点地区和聚集区,为基于问题的监测工作的开展提供技术支持。  相似文献   
5.
目的探讨益气活血通络方对蛛网膜下腔出血大鼠TGF-β/ERK信号通路的影响及神经保护作用。方法 SD大鼠随机分为假手术组,模型组,益气活血通络方5、10、15 g/kg组和尼莫地平组,除假手术组外,其余各组建立蛛网膜下腔出血模型大鼠,分组处理后,各组大鼠进行神经功能缺损评分;以伊文思蓝染料外渗实验检测大鼠血脑屏障通透性;以TUNEL染色检测大鼠脑皮质神经细胞凋亡情况;以酶联免疫吸附法(ELISA)检测大鼠血清肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)水平;以蛋白免疫印迹法检测大鼠脑皮质组织TGF-β/ERK通路相关蛋白TGF-β1、p-ERK/ERK表达情况。结果与假手术组相比,模型组大鼠神经功能缺损评分、伊文思蓝渗出量、TUNEL阳性细胞比例、血清IL-6、TNF-α水平、TGF-β1表达、p-ERK/ERK明显升高(P0.05)。与模型组相比,益气活血通络方5、10、15 g/kg组和尼莫地平组大鼠神经功能缺损评分、伊文思蓝渗出量、TUNEL阳性细胞比例、血清IL-6、TNF-α水平、TGF-β1表达和p-ERK/ERK水平明显降低(P0.05),且益气活血通络方各组呈剂量相关性,益气活血通络方15 g/kg组与尼莫地平组相比,各指标比较差异无统计学意义。结论益气活血通络方可下调TGF-β/ERK信号,保护蛛网膜下腔出血大鼠神经功能。  相似文献   
6.
赵胜楠  侯鹏 《中国药事》2020,34(7):759-765
异常毒性最初是一种确保复杂成分制剂生产工艺一致性及安全性的辅助检测手段,后来成为针对外源性毒性污染物的通用安全性检测项,曾在世界范围内被各国药典收载。由于该检测与药品质量、安全性之间的关联性受到质疑,各国药典逐渐在各论及通则中删除该检测项,目前仅《中国药典》保留异常毒性。由于该检测存在设定限值难以统一、给药体积及给药剂量不合理、结果易受干扰且缺乏明确的判定标准等试验原理及设计上的缺陷,导致其试验结果没有实际参考意义。基于对历史数据的回顾分析,国际监管机构及卫生组织对异常毒性有了更为科学的认知,并已逐渐形成统一的监管共识:严格的生产控制措施和有效的质量检测手段,比异常毒性检测更为重要;异常毒性检测结果或与产品质量及污染不具相关性;在异常毒性检查中使用大量动物不符合动物福利和“3R”原则。本文从科学角度试论异常毒性作为药品质量控制指标的合理性,并总结异常毒性修订的科学原则,希望能为我国监管机构、制药行业修订异常毒性相关内容提供思考角度。  相似文献   
7.
目的探究右美托咪定不同给药方式在子宫肌瘤微创手术患者中的应用效果对比。方法选取于本院诊治的子宫肌瘤并进行微创手术的患者,分为两组,每组30例。第一组,单次注射组(SI组);第二组,持续注射组(CI组)。SI组和CI组患者在一般资料上差异无统计学意义。通过分析SI组和CI组患者心率、平均动脉压、应激反应相关指标、继发效应的差异性来探究右美托咪定不同给药方式在子宫肌瘤微创手术患者中的应用效果对比。结果在T0时间点,SI组和CI组患者心率、平均动脉压指标数据相近(P>0.05),在T1、T2时间点,SI组患者平均动脉压、心率等指标比CI组优良(P<0.05)。麻醉前,SI组和CI组患者应激反应相关指标数值相差较小(P>0.05),术后,SI组患者应激反应相关指标比CI组优良(P<0.05)。两组患者继发效应发生情况差异无统计学意义(P>0.05)。结论右美托咪定在手术过程中麻醉效果显著,但单次注射的方法对患者的麻醉效果更佳,继发效应更少。  相似文献   
8.
萧惠来 《现代药物与临床》2020,43(12):2398-2403
介绍欧盟和美国有关药品说明书[适应症]项目撰写的法规和指导原则,特别是最近欧洲药品管理局(EMA)发布的"治疗适应症的用语"。从这些管理文件得到的启示是相关法规规定不宜太粗糙,应具体、精准,应包括内容和格式的规定;而且要有指导原则伴随,以保证法规落到实处。熟悉掌握药品说明书[适应症]项目的撰写要求对规范撰写其他项目有普遍指导意义,对于药品说明书的监管也有裨益。  相似文献   
9.
ObjectiveThe aim of this study was to assess the clinicopathological features of florid cemento-osseous dysplasia (FCOD)-related osteonecrosis highlighting their histopathological aspects and bone structure.MethodsTwenty-two FCOD-related osteonecrosis cases were evaluated retrospectively. Osteonecrosis, osteomyelitis, bacterial colonization, bone resorption, reactive bone, osteon-like structure, lamellar bone, and basophilic lines were analyzed. Specific staining and fluorescence and polarized light microscopy analyses were also performed.Results: The mandible was more affected by FCOD-related osteonecrosis. There was a predominance of African-Brazilian women in the fifth and seventh decades of life. Osteomyelitis was present in 82 % of cases whereas bone resorption and bacterial colonization were present in 100 % of FCOD-related osteonecrosis cases. Thick basophilic lines were seen in all cases (100 %). Actinomycosis and osteoclasts were not often.ConclusionsThis study showed female adult preference, mandibular location, and some findings such as osteomyelitis, bone resorption, and bacterial colonization were histopathological features more frequent in FCOD-related osteonecrosis. In the absence of a close clinical and radiographic correlation, the morphology of the necrotized bone similar to cementum could help to recognize FCOD.  相似文献   
10.
AimGenomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear.Methods and resultsWe evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity.ConclusionsMTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available.  相似文献   
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