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991.
目的 :验证从牛皮质骨中提取的骨形态发生蛋白 (bBMP)的异位诱导成骨能力 ,探讨煅桡骨 (SB)作为其载体对骨缺损的治疗作用。方法 :①将bBMP植入 1 6只balb/c小鼠肌袋内 ,每周宰杀 4只行细胞学检查 ,连续 4周。② 1 6只新西兰大白兔手术造成双侧桡骨 1cm缺损 ,分别植入bBMP -SB和SB进行自身对照 ,分批宰杀后行X -线照片和组织学检查。结果 :植入肌袋内的bBMP术后一周即可诱导软骨细胞形成 ,2周时可见编织骨 ,4周时可见小梁骨及骨髓成形。而骨缺损实验中 ,bBMP -SB组在软骨诱导、小梁骨的形成数量、骨折愈合等方面均明显优于单纯SB组。结论 :①bBMP有强大的异位诱导成骨能力 ;②bBMP -SB复合骨可促进骨缺损愈合  相似文献   
992.
用双-2-乙基己基酚酞酸酯(DEHP)诱导大鼠肝过氧化物酶体增殖,然后用蔗糖密度梯度离心法分离大鼠肝微粒体,用毛细管气相色谱法测定肝微粒体中的脂肪酸含量.结果不饱和脂肪酸占所测14种脂肪酸总量的比例,青年诱导组小于青年正常组(P<0.01),老年诱导组大于老年正常组(P<0.05).青年正常组大于老年正常组(P<0.01).所测14种脂肪酸的总量及长链脂肪酸占总量的比例,各实验组之间均无明显差异.说明DEHP对大鼠肝微粒体脂肪酸的组成,进而对微粒体膜结构的影响,青年鼠与老年鼠不同.结论青年鼠与老年鼠对药物代谢的能力不同.  相似文献   
993.
Zhao  Peng  Li  Xiaqiu  Li  Yang  Zhu  Jiaying  Sun  Yu  Hong  Jianli 《International urology and nephrology》2021,53(10):2177-2187
Purpose

Diabetic nephropathy (DN) is one of the most serious complications of diabetes that leads to decline of renal function. Although numerous studies have revealed that microRNAs (miRNAs) play essential roles in the progression of DN, whether miR-365 is involved remains elusive.

Methods

The successful construction of DN model was confirmed by ELSIA, hematoxylin–eosin (HE) and Masson staining assay. The expression of miR-365 was detected through RT-qPCR. The levels of BDNF, p-TrkB, α-smooth muscle actin (SMA), collagen IV (Col.IV), transforming growth factor-β1 (TGF-β1), tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6) were evaluated by western blot, IF or ELISA assays. Luciferase reporter assay was used to detect the interaction between miR-365 and BDNF.

Results

The DN mice model was induced by streptozotocin (STZ). Then miR-365 expression was found to upregulate in tissues of DN rat. Furthermore, elevated expression of miR-365 was found in high glucose (HG)-treated HK-2 cells. Silencing of miR-365 suppressed the accumulation of ECM components and secretion of inflammatory cytokines in HK-2 cells. In addition, it was demonstrated that miR-365 could target BDNF. The protein levels of BDNF and p-TrkB were negatively regulated by miR-365 in HK-2 cells. Moreover, inhibition of miR-365 suppressed the levels of SMA, Col.IV, TGF-β1, TNF-α, and IL-6, indicating the renal fibrosis was inhibited by miR-365 knockdown.

Conclusion

MiR-365 could regulate BDNF-TrkB signal axis in STZ induced DN fibrosis and renal function. The results of the current study might provide a promising biomarker for the treatment of DN in the future.

  相似文献   
994.
Xiao  Bihuan  Jiang  Yuan  Wang  Bin  Hu  Yang  Sun  Yan  Wu  Yan  Qiao  Shuai 《Lasers in medical science》2021,36(6):1261-1266
Lasers in Medical Science - Large-scale long-term retrospective study of noninsulated microneedle radiofrequency treatment on neck rejuvenation is lacking. We conducted a 3-year retrospective...  相似文献   
995.
Wang  Jue  Wu  Jiang  Xu  Minghuo  Gao  Quanwen  Chen  Baoguo  Wang  Fang  Niu  Hao  Song  Huifeng 《Lasers in medical science》2021,36(6):1275-1282

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients’ satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P?<?0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

  相似文献   
996.
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm.  相似文献   
997.
Limited evidence has indicated that brain-derived neurotrophic factor (BDNF) may be involved in the neurobiology of premature ejaculation (PE). This study aimed to investigate BDNF levels in the central and peripheral nervous systems of a rapid ejaculation model. Eighteen male rats were selected and classified as ‘sluggish’, ‘normal’ and ‘rapid’ ejaculators on the basis of ejaculation frequency during copulatory behavioural tests. BDNF levels in specific brain regions, spinal cord and serum were determined by enzyme-linked immunosorbent assay (ELISA). Consistent with the results in PE patients, the concentration of serum BDNF decreased significantly from the sluggish rats to normal and rapid rats. Besides, in both brain regions and spinal cord, the sluggish group had the highest BDNF levels, while the rapid group had the lowest BDNF levels. Regression analyses of the expression of BDNF presented positive correlations between serum and brain (r = 0.958, p < .001), and between serum and spinal cord (r = 0.967, p < .001) respectively. Our findings suggested insufficient BDNF in the nervous system and serum may lead to rapid ejaculation. The current study adds to the evidence that BDNF is involved in the regulation of ejaculation.  相似文献   
998.
Wang  Jingjing  Yan  Lvjun  Ai  Ping  He  Yan  Guan  Hui  Wei  Zhigong  He  Ling  Mu  Xiaoli  Liu  Yanhui  Peng  Xingchen 《Neurosurgical review》2021,44(3):1447-1455

The optimal adjuvant treatment of high-risk low-grade glioma (LGG) is controversial. We performed this retrospective cohort study to compare three treatments including observation, radiotherapy (RT) alone, and radiotherapy combined with concomitant and adjuvant temozolomide (TMZ) chemotherapy (STUPP regimen) in patients with high-risk LGG. Patients with high-risk (age > 40 or undergoing subtotal resection or biopsy) LGG treated with observation or radiotherapy alone or STUPP regimen after operation were retrospectively analyzed. Survival rates were evaluated by the Kaplan-Meier method; the log-rank test was applied to compare differences between groups. A total of 250 patients met the inclusion criteria. Median follow-up for living people was 70 months. Overall, patients who received radiotherapy with or without temozolomide had better progression-free survival (PFS) and overall survival (OS) when compared with observation (median PFS: observation, 59 months; RT, 82 months; STUPP, not reached; median OS: observation, 96 months; RT, not reached; STUPP, not reached), whereas STUPP regimen did not further prolong PFS or OS than RT alone (PFS, P = 0.203; OS, P = 0.146). In oligodendroglioma (IDH mutant and 1p/19q codeleted) subtype, only STUPP regimen brought longer PFS when compared with observation (P = 0.008). The incidence of grade 3 or 4 neutropenia (P < 0.001) and nausea or vomiting (P = 0.004) was higher in the STUPP group than the figure for the RT alone group. PFS and OS were similarly improved in patients with high-risk LGG receiving RT alone or STUPP regimen. However, only STUPP regimen was able to bring better PFS for oligodendroglioma (IDH mutant and 1p/19q codeleted) subgroup. Longer follow-up time is needed to determine an association with treatment effect in different histological and molecular subgroups.

  相似文献   
999.
Lei  Cao  Chuzhong  Li  Chunhui  Liu  Peng  Zhao  Jiwei  Bai  Xinsheng  Wang  Yazhuo  Zhang  Songbai  Gui 《Neurosurgical review》2021,44(3):1737-1746
Neurosurgical Review - Since there are many approaches for successful craniopharyngioma resection, how to choose a suitable approach remains problematic. The aim of this study was to summarize...  相似文献   
1000.
目的探讨原发性中枢神经系统淋巴瘤(PCNSL)患者的预后因素及不同治疗方法的临床效果。方法回顾性分析1975年1月至2016年12月美国SEER数据库中4812例PCNSL患者的临床资料。其中男性2831例,女性1981例,男女比例为1.4∶1.0;发病年龄<60岁者2236例(46.47%),60~<75岁者1718例(35.70%),≥75岁者858例(17.83%);幕上肿瘤2417例(50.23%),幕下肿瘤299例(6.21%),脑内多发肿瘤554例(11.51%),其他或未指明部位的脑部肿瘤1542例(32.04%);弥漫大B细胞淋巴瘤(DLBCL)3513例(73.00%),非DLBCL 234例(4.86%),其他或未指明类型的淋巴瘤1065例(22.13%);治疗方式为单独活检的2010例(41.77%),单独部分切除61例(1.27%),单独完全切除54例(1.12%),活检+化疗2384例(49.54%),部分切除+化疗159例(3.30%),完全切除+化疗144例(2.99%)。采用单因素及多因素Cox回归模型分析影响患者总体生存的预后因素;采用Fine-Gray检验与竞争风险模型研究影响患者肿瘤特异性生存的预后因素;生存分析采用Kaplan-Meier法,并通过Log-rank进行比较。结果单因素及多因素Cox风险回归模型分析结果显示,影响PCNSL患者总体生存的独立预后因素包括年龄、种族、婚姻状态、肿瘤部位、病理学亚型、手术、化疗、合并其他恶性肿瘤、合并HIV感染等。Fine-Gray检验与竞争风险模型分析结果显示,影响患者肿瘤特异生存的独立预后因素包括年龄、种族、婚姻状态、肿瘤部位、病理学亚型、手术方式、化疗、合并其他恶性肿瘤、合并HIV感染,而性别与放疗均与肿瘤特异生存无明显相关性。与活检相比,PCNSL患者可能从手术切除中获益(部分切除:HR=0.805,95%CI:0.656~0.989,P=0.04;完全切除:HR=0.521,95%CI:0.414~0.656,P<0.01)。Kaplan-Meier生存分析结果显示,活检+化疗组中位生存时间为28个月(95%CI:24.497~31.503),单独活检组为2个月(95%CI:1.756~2.244),单独部分切除组为2个月(95%CI:1.410~2.590),单独完全切除组为19个月(95%CI:0~39.311),部分切除+化疗组为67个月(95%CI:46.187~87.813),完全切除+化疗组为84个月(95%CI:57.448~110.552),使用不同治疗方法的患者的中位生存时间的差异有统计学意义(P<0.01)。结论手术切除可能改善部分PCNSL患者的预后。化疗可能使肿瘤完全切除或部分切除患者的肿瘤特异生存时间延长。  相似文献   
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