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Bilateral eyestalk ablation in the freshwater prawn Macrobrachium lanchesteri results in high mortality, while unilateral eyestalk ablated prawns exhibited a high survival rate. There was marked increase in the growth of bilateral eyestalk-ablated prawns (47.70 mg/prawn) as compared to those that were unilaterally ablated (19.19 mg/prawn).  相似文献   
3.
The androgenic glands (AG) of male decapod crustaceans produce insulin-like androgenic gland (IAG) hormone that controls male sex differentiation, growth and behavior. Functions of the AG are inhibited by gonad-inhibiting hormone originating from X-organ-sinus gland complex in the eyestalk. The AG, and its interaction with the eyestalk, had not been studied in the blue swimmer crab, Portunus pelagicus, so we investigated the AG structure, and then changes of the AG and IAG-producing cells following eyestalk ablation. The AG of P. pelagicus is a small endrocrine organ ensheathed in a connective tissue and attached to the distal part of spermatic duct and ejaculatory bulb. The gland is composed of several lobules, each containing two major cell types. Type I cells are located near the periphery of each lobule, and distinguished as small globular cells of 5-7 μm in diameter, with nuclei containing mostly heterochromatin. Type II cells are 13-15 μm in diameter, with nuclei containing mostly euchromatin and prominent nucleoli. Both cell types were immunoreactive with anti-IAG. Following bilateral eyestalk ablation, the AG underwent hypertrophy, and at day 8 had increased approximately 3-fold in size. The percentage of type I cells had increased more than twice compared with controls, while type II cells showed a corresponding decrease.  相似文献   
4.
The androgen receptor (AR) regulates growth and progression of androgen-dependent as well as androgen-independent prostate cancer cells. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists have been reported to reduce AR activation in androgen-dependent LNCaP prostate cancer cells. To determine whether PPARγ ligands are equally effective at inhibiting AR activity in androgen-independent prostate cancer, we examined the effect of the PPARγ ligands ciglitazone and rosiglitazone on C4-2 cells, an androgen- independent derivative of the LNCaP cell line. Luciferase-based reporter assays and Western blot analysis demonstrated that PPARγ ligand reduced dihydrotestosterone (DHT)-induced increases in AR activity in LNCaP cells. However, in C4-2 cells, these compounds increased DHT-induced AR driven luciferase activity. In addition, ciglitazone did not significantly alter DHT-mediated increases in prostate specific antigen (PSA) protein or mRNA levels within C4-2 cells. siRNA-based experiments demonstrated that the ciglitazone-induced regulation of AR activity observed in C4-2 cells was dependent on the presence of PPARγ. Furthermore, overexpression of the AR corepressor cyclin D1 inhibited the ability of ciglitazone to induce AR luciferase activity in C4-2 cells. Thus, our data suggest that both PPARγ and cyclin D1 levels influence the ability of ciglitazone to differentially regulate AR signaling in androgen-independent C4-2 prostate cancer cells.  相似文献   
5.
目的:评估胃癌根治术同时性射频消融治疗在治疗胃癌肝转移的临床意义。方法:收集2008年1月至2010年12月19例胃癌肝转移患者,合计转移灶33个,转移灶小于4厘米,且合计不超过4个转移灶。射频消融治疗在术中超声引导下完成。Kap-lan—Meier法分析无病生存期,无肝转移生存期及总生存期。对临床病理学因子及肝转移相关因子采用Log-rank法Cox风险比例模型解析。结果:中位无病生存、无肝转移生存及总生存期为355,394及488天。有3例患者获得长期的无复发生存。单因素分析显示,较早的T分期、N分期,较少的转移灶数量,较小的转移灶直径与良好的预后相关。多因素分析提示,病灶数量与病灶直径为独立预后因子。结论:肝转移射频消融治疗安全性好,对单发的小于4cm转移灶,以及多发病灶合计直径小于4cm者射频消融治疗较为适用,可有显著生存获益。部分患者可迭临床治愈。对于胃癌肝转移的合适病例,射频消融治疗值得推广。  相似文献   
6.
Acute kidney injury (AKI) is characterized by high mortality rates from deterioration of renal function over a period of hours or days that culminates in renal failure1. AKI can be caused by a number of factors including ischemia, drug-based toxicity, or obstructive injury1. This results in an inability to maintain fluid and electrolyte homeostasis. While AKI has been observed for decades, effective clinical therapies have yet to be developed. Intriguingly, some patients with AKI recover renal functions over time, a mysterious phenomenon that has been only rudimentally characterized1,2. Research using mammalian models of AKI has shown that ischemic or nephrotoxin-injured kidneys experience epithelial cell death in nephron tubules1,2, the functional units of the kidney that are made up of a series of specialized regions (segments) of epithelial cell types3. Within nephrons, epithelial cell death is highest in proximal tubule cells. There is evidence that suggests cell destruction is followed by dedifferentiation, proliferation, and migration of surrounding epithelial cells, which can regenerate the nephron entirely1,2. However, there are many unanswered questions about the mechanisms of renal epithelial regeneration, ranging from the signals that modulate these events to reasons for the wide variation of abilities among humans to regenerate injured kidneys.The larval zebrafish provides an excellent model to study kidney epithelial regeneration as its pronephric kidney is comprised of nephrons that are conserved with higher vertebrates including mammals4,5. The nephrons of zebrafish larvae can be visualized with fluorescence techniques because of the relative transparency of the young zebrafish6. This provides a unique opportunity to image cell and molecular changes in real-time, in contrast to mammalian models where nephrons are inaccessible because the kidneys are structurally complex systems internalized within the animal. Recent studies have employed the aminoglycoside gentamicin as a toxic causative agent for study of AKI and subsequent renal failure: gentamicin and other antibiotics have been shown to cause AKI in humans, and researchers have formulated methods to use this agent to trigger kidney damage in zebrafish7,8. However, the effects of aminoglycoside toxicity in zebrafish larvae are catastrophic and lethal, which presents a difficulty when studying epithelial regeneration and function over time. Our method presents the use of targeted cell ablation as a novel tool for the study of epithelial injury in zebrafish. Laser ablation gives researchers the ability to induce cell death in a limited population of cells. Varying areas of cells can be targeted based on morphological location, function, or even expression of a particular cellular phenotype. Thus, laser ablation will increase the specificity of what researchers can study, and can be a powerful new approach to shed light on the mechanisms of renal epithelial regeneration. This protocol can be broadly applied to target cell populations in other organs in the zebrafish embryo to study injury and regeneration in any number of contexts of interest.  相似文献   
7.
目的:探讨颅咽部数字X线指数对阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者行低温射频消融手术治疗效果的评价作用。方法:选择2013年10月-2015年10月在我院接受低温射频消融术的OSAHS患者74例作为研究组,另选择同期在我院接受体检的健康志愿者44例作为对照组。分别于手术前后采用X线测量两组研究对象的上齿槽座角(SNA)、下齿槽座角(SNB)、上下齿槽座角(ANB)、颌上角(NA/PA);舌根后方气道前后径(PAS)、软腭后方气道横径(U-MPW)、会厌层气道前后径(V-LPW)、后鼻棘-咽顶点距(PNS-R)、舌骨最上缘至下颌骨垂直距离(H-MP)、软腭长度(SPL)、软腭厚度(SPT)以及舌骨至颈椎前平面距(H-CVP)。结果:研究组患者ANB,NA/PA,PAS,U-MPW,PNS-R及H-CVP均大于对照组,差异具有统计学意义(P0.05);两组SNA、SNB、V-LPW、H-MP、SPL及SPT比较,差异无统计学意义(P0.05);与术前相比,研究组患者术后ANB、PAS、U-MPW及H-CVP均明显改善,差异具有统计学意义(P0.05)。结论:颅咽部数字X线测量指数能够较好的评价OSAHS患者行射频消融术的治疗效果,值得临床参考。  相似文献   
8.
摘要 目的:探讨二陈汤加减联合微波消融术(MWA)对晚期非小细胞肺癌(NSCLC)患者辅助性T细胞17(Th17)/调节性T细胞(Treg)失衡和血管生成因子的影响。方法:选择2020年9月~2022年9月期间我院收治的120例不可或不愿手术切除或体部立体定向放疗的ⅢB-Ⅳ期并同意MWA治疗的NSCLC患者。采用随机对照的方法将所有患者分为观察组(二陈汤加减联合MWA治疗,60例)及对照组(MWA治疗,60例)。对比两组中医主要证候总评分、EORTC生命质量测定量表(EORTC QLQ-C30)评分、Th17/Treg失衡、血清肿瘤标志物、血管生成因子和不良反应发生率。结果:治疗后,观察组中医主要证候总评分、EORTC QLQ- C30评分低于对照组(P<0.05)。治疗后,观察组Th17细胞比例、Treg细胞比例低于对照组,Th17/Treg比值高于对照组(P<0.05)。治疗后,观察组癌胚抗原(CEA)、鳞状细胞癌相关抗原(SCC-Ag)和角化素蛋白片段19(Cyfra21-1)低于对照组(P<0.05)。治疗后,观察组血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)低于对照组(P<0.05)。两组不良反应发生率组间对比未见差异(P>0.05)。结论:二陈汤加减联合MWA对晚期NSCLC患者,可有效降低血清肿瘤标志物水平,促进临床症状改善,调节Th17/Treg比例失衡和血管生成因子。  相似文献   
9.
文章对眼组织细胞内的激光等离子体诱导蚀除的发展现状、物理机理及未来趋势做了综合评述,并从理论上解释了眼组织内等离子体的屏蔽机制,同时提出了更有效蚀除即把副作用降低到最低限度的解决办法。  相似文献   
10.
摘要 目的:探讨实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓患者的疗效及对血清BCL-2同源的水溶性相关蛋白(Bax)、细胞角蛋白19片段(Cyfra21-1)的影响。方法:选择本院2017年1月到2021年4月收治的原发性肝癌合并门静脉癌栓患者82例作为研究对象,根据1:1随机数字表法将患者分为虚拟导航组与对照组各41例,虚拟导航组给予实时影像融合的超声虚拟导航技术联合射频消融术治疗,对照组给予单纯超声引导联合射频消融术治疗。结果:虚拟导航组的进针次数、融合时间、布针时间少于对照组(P<0.05);虚拟导航组治疗后3个月的胆汁瘤、肝脓肿、膈肌损伤、肺部感染等并发症发生率为4.9 %,低于对照组的29.3 %(P<0.05)。虚拟导航组治疗后3个月的总有效率为82.9 %,高于对照组的51.2 %(P<0.05)。两组治疗后3个月的血清谷丙转氨酶(ALT)、谷草转氨酶(AST)水平低于治疗前,虚拟导航组低于对照组(P<0.05)。两组治疗后的血清Bax、Cyfra21-1含量低于治疗前,虚拟导航组低于对照组(P<0.05)。结论:实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓能降低血清Bax、Cyfra21-1含量,改善患者的肝功能,提高消融效率,还可减少并发症的发生,最终提高患者的总体治疗效果。  相似文献   
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