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41.
Cancer stem cells (CSCs) are a relatively rare subpopulation of tumor cell with self-renewal and tumorigenesis capabilities. CSCs are associated with cancer recurrence, progression, and chemoradiotherapy resistance. Establishing a reliable platform for CSC enrichment and study is a prerequisite for understanding the characteristics of CSCs and discovering CSC-related therapeutic strategies. Certain strategies for CSC enrichment have been used in laboratory, particularly fluorescence-activated cell sorting (FACS) and mammosphere culture. However, these methods fail to recapitulate the in vivo chemical and physical conditions in tumors, thus potentially decreasing the malignancy of CSCs in culture and yielding unreliable research results. Accumulating research suggests the promise of a biomaterial-based three-dimensional (3D) strategy for CSC enrichment and study. This strategy has an advantage over conventional methods in simulating the tumor microenvironment, thus providing a more effective and predictive model for CSC laboratory research. In this review, we first briefly discuss the conventional methods for CSC enrichment and study. We then summarize the latest advances and challenges in biomaterial-based 3D CSC platforms. Design strategies for materials, morphology, and chemical and physical cues are highlighted to provide direction for the future construction of platforms for CSC enrichment and study.  相似文献   
42.
目的:探讨经尿道射精管切开术(transurethral resection of ejaculatory duct, TURED)治疗射精管梗阻(ejaculatory duct obstruction, EDO)的效果。方法:2004年10月至2010年10月期间收治60例EDO患者,常规采用精液分析、精浆果糖和经直肠超声检查对其进行诊断,必要时行输精管造影检查。60例EDO患者均行TURED治疗,术后随访其疗效。结果:60例EDO患者的精液量为0.2~3.5 mL,平均(1.10±0.76) mL,pH值5.8~7.6,平均6.5±1.4;精浆果糖为一次射精0~51.4 μmol,平均为(5.86±2.19) μmol。经直肠超声检查结果为:单纯射精管扩张者15例,前列腺囊肿6例,单纯双侧精囊扩张10例,单侧精囊扩张4例,精囊扩张并射精管扩张10例,精囊扩张合并前列腺囊肿5例,单侧精囊扩张并对侧精囊发育不良或缺乏2例,精囊扩张并射精管扩张和钙化3例,单侧精囊扩张并射精管扩张和对侧精囊发育不良或缺乏5例。所有患者均完成手术,术后随访6~78个月。60例EDO患者行TURED术后,51例(85.0%)精液检查有不同程度的改善,16例(26.7%)妻子妊娠。结论:TURED是治疗EDO的一种简单、微创和有效的方法。  相似文献   
43.
黄芩甙大鼠小肠吸收的研究   总被引:4,自引:0,他引:4  
本文作者对文献介绍的大鼠在体小肠回流实验装置进行了改进,并用来研究黄芩甙的吸收情况和胆管结扎与不结扎对黄芩甙吸收的影响。胆管结扎与不结扎的药动学参数为:平均吸收半衰期分别是15.45h~(-1)、11.42h~(-1)。最终吸收程度依次是24.44%,31.58%。经方差分析两者无显著差异(F<5.3)。  相似文献   
44.
Macro fiber composite (MFC), which are new ultrathin piezoelectric smart materials, are mostly applied in the fields of shell structure deformation and vibration control. Among others, the application of embedded MFCs in sandwich structures has received wide attention. Currently, its actuating force formula is primarily acquired based on the Bernoulli–Euler Model, which does not consider the shear lag effect and actuating force of MFC ends. To study the actuating performance of an MFC in a sandwich structure, according to its action characteristics, the MFC is divided into upper and lower actuating units without any interaction between to two under the condition of plane strain, and the shear lag effect is considered between the units and the top and bottom of the sandwich structure. The actuating force of the MFC ends is obtained by considering its influence on the bending deformation of the sandwich structure, which deduces the actuating force formula of the embedded MFC. In contrast to ANSYS piezoelectric simulation, the distribution of the MFC interior normal stress is similar to the result from ANSYS piezoelectric simulation, and there is a very small deviation between the MFC end and central normal stress and the result from ANSYS piezoelectric simulation. Taking the end deflection of the sandwich structure with an embedded MFC as an example, the actuating force simulation of the MFC considering the shear lag effect is compared with the ANSYS piezoelectric simulation and actuating force simulation based on the Bernoulli–Euler model. The result indicates that the actuating force simulation of the MFC considering the shear lag effect is closer to the ANSYS piezoelectric simulation, which proves the rationality and necessity of considering the shear lag effect and end actuating force of the MFC.  相似文献   
45.
Primary glomerular disease was the leading cause of chronic kidney disease (CKD) in China; however, changes in the economy and environment introduce variations in the spectrum of kidney diseases. This study aimed to analyze renal biopsy data to inform disease prevention and public health interventions. In this retrospective cohort study, data from 2,803 consecutive renal biopsies conducted at our center between January 2010 and December 2018 were analyzed. The sample was disaggregated by age and the date of biopsy to facilitate analysis. Primary glomerulonephritis (PGN) is the most frequent (81.84%) finding, followed by secondary glomerulonephritis (SGN; 15.38%), tubulointerstitial nephritis (15.38%), and others (1.57%). IgA nephropathy (IgAN), idiopathic membranous nephropathy (iMN), and minimal change disease were the primary causes of PGN. Among PGN cases, the incidence of iMN arose, especially among those aged ≥ 60 years old, during the observation period. Contrary to the case of iMN, the proportion of IgAN in PGN trended downward, continuously, and at length. Moreover, IgAN mainly affected those aged 25–44 years old and less so those aged ≥ 60 years old. Lupus nephritis, Henoch–Schönlein purpura nephritis, and diabetic nephropathy (DN) were key causes of SGN. A ratio reversal between infectious disease and chronic disease dramatically changed SGN patterns. In the past year, the incidence of hepatitis B–related nephritis has constantly declined; however, the proportion of DN among SGN had steadily increased. The incidence of iMN significantly increased during these years. Among SGN cases, the proportion of DN has increased.  相似文献   
46.
There are an estimated 5.4 million snakebite cases every year. People with snakebite envenoming suffer from severe complications, or even death. Although some review articles cover several topics of snakebite envenoming, a review of the cases regarding cerebral complications, especially rare syndromes, is lacking. Here, we overview 35 cases of snakebite by front-fanged snakes, including Bothrops, Daboia, Cerastes, DeinagkistrodonTrimeresurus, and Crotalus in the Viperidae family; Bungarus and Naja in the Elapidae family, and Homoroselaps (rare cases) in the Lamprophiidae family. We also review three rare cases of snakebite by rear-fanged snakes, including Oxybelis and Leptodeira in the Colubridae family. In the cases of viper bites, most patients (17/24) were diagnosed with ischemic stroke and intracranial hemorrhage, leading to six deaths. We then discuss the potential underlying molecular mechanisms that cause these complications. In cases of elapid bites, neural, cardiac, and ophthalmic disorders are the main complications. Due to the small amount of venom injection and the inability to deep bite, all the rear-fanged snakebites did not develop any severe complications. To date, antivenom (AV) is the most effective therapy for snakebite envenoming. In the six cases of viper and elapid bites that did not receive AV, three cases (two by viper and one by elapid) resulted in death. This indicates that AV treatment is the key to survival after a venomous snakebite. Lastly, we also discuss several studies of therapeutic agents against snakebite-envenoming-induced complications, which could be potential adjuvants along with AV treatment. This article organizes the diagnosis of hemotoxic and neurotoxic envenoming, which may help ER doctors determine the treatment for unidentified snakebite.  相似文献   
47.
目的:探讨胎儿咽、食管肌层中α-平滑肌肌动蛋白(α-smouth muscle actin,α-SMA)、肌球蛋白重链Ⅱ(myosin heary chain-Ⅱ、MHC-Ⅱ)、MHC-Ⅰ表达及其空间分布。方法:采用免疫组织化学SABC法及蛋白印迹法对20例胎儿咽、食管的α-SMA、MHC-Ⅰ、MHC-Ⅱ表达进行观察。结果:MHC-Ⅱ和MHC-Ⅰ共定位食管上、中段肌层,并主要表达在外部纵行肌,由上至下逐渐减少,至食管下段消失。而α-SMA则在食管上端内层肌开始表达,呈环行排列,由上至下逐渐增加,并由内肌层扩展到外肌层。结论:α-SMA、MHC-Ⅰ、MHC-Ⅱ共存于胎儿食管上中段,骨骼肌和平滑肌的移行呈渐进性,无明确界线。  相似文献   
48.
用所制备的复制型M13mp18和寡核苷酸(GACA)_4探针,分别与近交系AKR小鼠的9个个体及NOD小鼠的5个个体进行DNA杂交,结果提示,一种探针和近交系内各个体杂交的DNA指纹图完全一致;同一探针与不同近交系小鼠杂交的指纹图完全不同;不同探针与同一近交系小鼠杂交的指纹图也完全不同。说明用DNA指纹图分析,对建立各种实验动物标准的DNA指纹图,用于遗传监测、杂交育种、基因制图以及寻找遗传标记等均有实用价值和参考作用。  相似文献   
49.
 目的 探讨自噬在张力诱导终板软骨细胞退变过程中的变化及作用。方法 取10只清洁级SD大鼠腰椎终板软骨进行细胞培养。对P1代终板软骨细胞分别加载间歇循环张力(10%伸长率,0.5 Hz)0 h、3 h、12 h、24 h、48 h。以倒置相差显微镜观察细胞形态学变化,实时PCR与蛋白印迹法检测软骨标志基因Ⅱ型胶原、转录因子SOX-9及蛋白多糖转录因子、Beclin-1和LC3基因表达的变化,以单丹磺酰戊二胺染色观察自噬小体。MTT(3-2,5-二苯基四氮唑溴盐染色)法检测3-甲基腺嘌呤(自噬抑制剂)刺激前后的细胞存活率。结果 间歇循环张力诱导后0 h组与3 h组为正常终板软骨细胞形态,呈多角形;12 h组略呈不规则形;24 h组和48 h组呈梭形改变。实时PCR显示24 h组和48 h组中Ⅱ型胶原、转录因子SOX-9及蛋白多糖的表达量降低;自噬相关基因LC3和Beclin-1表达量呈时间依赖性增加。单丹磺酰戊二胺染色显示24 h组和48 h组自噬发生率呈时间依赖性增加。MTT结果显示细胞存活率呈降低趋势;添加3-甲基腺嘌呤刺激后细胞活性减弱、存活率降低。结论 间歇循环张力刺激下终板软骨细胞表型逐渐丧失;自噬相关基因LC3与Beclin-1表达明显上调,但细胞活性降低;抑制自噬水平可降低细胞存活率,提示自噬参与了间歇循环张力诱导的终板软骨细胞退变过程。  相似文献   
50.
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