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长江中下游部分湖泊沉积物碱性磷酸酶分布及其作用研究   总被引:5,自引:0,他引:5  
沉积物磷负荷在湖泊富营养化的发生与恢复过程中具有关键作用,其释放受物理、化学与生物机制调节,而碱性磷酸酶催化有机磷的矿化,故当为促进沉积物磷循环的重要因素。本文讨论了长江中下游部分湖泊沉积物碱性磷酸酶分布及其在磷释放过程中的作用。五里湖疏浚与未疏浚区以及太湖、巢湖、龙感湖、东湖、月湖、龙阳湖、莲花湖等不同湖泊的不同区域表层沉积物碱性磷酸酶活性(APA)明显不同,这种空间异质性与湖泊富营养化程度相联系。此外,APA随沉积物的深度递减,或在中间与较深层次出现峰值,且具明显的季节性。上述事实以及APA对抑制剂的不同响应方式暗示酶存在形态的多样性(同工酶)。苯丙氨酸(Phe)明显提高月湖与五里湖沉积物APA,沉积物与Phe相互作用并静置一天之后,生物可利用性磷(SRP)的释放量明显增加。再者,Phe可抑制月湖沉积物APA,沉积物与Phe相互作用并静置一天之后,SRP释放量无明显变化,溶解有机磷(DOP)的释放量则明显增加。因此,释放的SRP部分来自某些活跃的有机磷的酶促水解,沉积物碱性磷酸酶在内源磷的释放以及富营养化过程中具有重要作用。  相似文献   
2.
Tao  Zhuo-Ying  Qiu  Xin-Yi  Wei  Si-Qi  Bai  Guang  Li  Jin-Feng  Cao  Dong-Yuan 《Neurochemical research》2022,47(5):1405-1418
Neurochemical Research - Epigenetic regulation of gene expression has been implicated in the development of chronic pain. However, little is known about whether this regulation is involved in the...  相似文献   
3.

Background

Lymph node metastasis has a significant impact on laryngeal cancer prognosis. The role of lymph node ratio (LNR, ratio of metastatic to examined nodes) in the staging of laryngeal cancer was not reported.

Patients and Methods

Records of laryngeal cancer patients with lymph node involvement from Surveillance, Epidemiology, and End Results database (SEER, training set, N = 1963) and Fudan University Shanghai Cancer Center (FDSCC, validating set, N = 27) were analyzed for the prognostic value of LNR. Kaplan–Meier survival estimates, the Log-rank χ2 test and Cox proportional hazards model were used for univariate and multivariate analysis. Optimal LNR cutoff points were identified by X-tile.

Results

Optimal LNR cutoff points classified patients into three risk groups R1 (≤0.09), R2 (0.09–0.20) and R3 (>0.20), corresponding to 5-year cause-specific survival and overall survival in SEER patients of 55.1%, 40.2%, 28.8% and 43.1%, 31.5%, 21.8%, 2-year disease free survival and disease specific survival in FDSCC patients of 74.1%, 62.5%, 50.0%, and 67.7%, 43.2%, 25.0%, respectively. R3 stratified more high risk patients than N3 with the same survival rate, and R classification clearly separated N2 patients to 3 risk groups and N1 patients to 2 risk groups (R1–2 and R3).

Conclusions

R classification is a significant prognostic factor of laryngeal cancer and should be used as a complementary staging system of N classification.  相似文献   
4.
湖北省若干浅水湖泊沉积物有机质与富营养化的关系   总被引:11,自引:3,他引:8  
分析了湖北省月湖、龙阳湖、后官湖、梁子湖、牛山湖、保安湖、鲁湖等7个湖泊表层沉积物有机质、总氮与总磷的含量,并考察了其在月湖、龙阳湖沉积物中的垂直分布及月湖、龙阳湖与保安湖表层沉积物的颗粒组成,结果表明:位于城市与城郊的月湖与龙阳湖表层沉积物有机质含量较高,且表现出沿岸带较丰富的空间分布特征。在垂直及水平方向上,有机质与总氮和总磷含量均显著相关,颗粒组成与有机质和总氮含量亦显著相关。有机质富集应是促进城市湖泊富营养化的重要因素。  相似文献   
5.
鸟苷酸-四联体DNA (G4 DNA)是由富含串联重复鸟苷酸(G)的DNA或RNA序列形成的G4片层,并堆叠而成一类独特的核酸二级结构。G4 DNA结合多种特异性配体可形成具有催化过氧化氢活性的G4 DNA模拟酶(G4 DNAzyme)。由于G4 DNAzyme存在着序列构成简便灵活、适合多样传感平台检测等特点,其在新型生物传感方法研发、医学检测新技术研究等领域中应用前景广阔。本文主要依据G4 DNA结合配体的不同,对近年来新发展出的G4 DNAzyme进行分类与回顾,归纳为含氯化血红素(hemin)的G4-Hemin DNAzyme与非G4-Hemin DNAzyme。前者是目前G4 DNA模拟酶的研究主流——本文主要归纳了G4-Hemin DNAzyme在金属阳离子、生物小分子及生物大分子的检测分析方向上所取得的重要研究进展,并阐述其在生物传感领域的影响和优势;后者中的配体则主要包括金属阳离子N-甲基吗啡啉(4-methylmorpholine, NMM)、硫磺素T(thioflavin T,ThT)及新型金属配体(Cu2+Ce3+)等。...  相似文献   
6.
Notch通路是与细胞增殖、分化、凋亡等密切相关的通路,其相关蛋白表达异常参与多种疾病的发生,但其在宫腔粘连中的作用尚不清楚.为探讨jagged1/notch1在宫腔粘连(IUAs)发病中的作用,本实验选择经宫腔镜诊断为宫腔粘连患者40例为IUAs组,非宫腔粘连患者25例为对照组,宫腔镜直视下取子宫内膜组织,采用实时荧光定量PCR法检测jagged1、notch1 mRNA表达,发现IUAs组jagged1、notch1的表达显著高于对照组.免疫荧光染色、免疫组织化学和Western印迹技术检测jagged1、notch1蛋白表达. 结果显示,与对照组相比,IUAs组jagged1、notch1蛋白表达水平均明显升高.以上结果表明, Notch通路相关因子jagged1、notch1的高表达可能与宫腔粘连的发生发展有关.  相似文献   
7.
番石榴挥发物对桔小实蝇成虫的引诱作用   总被引:4,自引:0,他引:4  
利用Y型嗅觉仪测试了性成熟与性未成熟不同生理状态下桔小实蝇Bactrocera dorsalis雌雄成虫对番石榴叶、果肉及番石榴叶主要挥发成分石竹烯的反应.结果显示,测试剂量为1g和10g的番石榴叶和果肉对性成熟与性未成熟的两性成虫均能产生显著的引诱效果,且反应均在10min时达到显著水平.测试剂量为5mg和10mg的石竹烯对性成熟雌虫、性成熟雄虫和性未成熟雄虫均无引诱作用,但对性未成熟雌虫在60 min时产生显著引诱效果.  相似文献   
8.

Background

Rs2910164, a Single nucleotide polymorphism (SNP) located in the precursor microRNA sequence of miR-146a, is the only MicroRNA sequence SNP studied in papillary thyroid cancer (PTC). Association studies had been performed in US and UK-Northern European populations, but results were inconsistence. This study evaluated the association between rs2910164 and the risk of PTC as well as benign thyroid tumor (BN), and examined the clinicopathological characteristics of PTC and BN for different genotypes.

Methods

This case-control study genotyped rs2910164 in 753 PTCs, 484 BNs and 760 controls in a Chinese Han population. Clinicopathological and genetic data were collected and compared. Multivariate logistic regression was performed to calculate adjusted odds ratios (ORs).

Results

There were no differences in rs2910164 genotype distributions between the three groups. PTC cases with three genotypes (CC, CG, GG) had similar clinicopathological characteristics except the existence of “para-cancer” BN (PTC/BN, P = 0.006). PTC/BN patients were older (P = 0.009), and had smaller cancer lesions (P<0.001), lower serum thyrotropin levels (1.82±1.42 vs. 2.21±1.74, P = 0.04), and lower rates of level VI lymph node metastasis (20.8% vs. 52.7%, P<0.001) and lateral neck lymph node metastasis (11.5% vs. 23.0%, P = 0.011) compared with PTC only. Then we supposed a possible progression from BN to PTC which may involve rs2910164 in and performed a multivariate logistic regression analysis of PTC/BN and BN cases to determine risk factors of this progression. Results showed that the rs2910164 GG homozygote (OR = 2.25, 95% CI 1.22–4.14, P = 0.01) was the only risk factor in this study.

Conclusion

Rs2910164 was not associated with increased risk of PTC and BN in Chinese patients, but may play a latent role in the transformation from BN to PTC.  相似文献   
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