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81.
Changes in the activities of △5-3β-hydroysteroid dehydrogenase (HSD) in testis and adrenal gland, 17β-hydroxysteroid dehydrogenase in testis, acid and alkaline phosphatase in testis, prostate and seminal vesicle were observed in noise exposed mature rats at the intensity of 85 dB for 8 h/day for 45 days. The results indicated that noise exposed group showed a significant diminution in the activities of androgenic key enzymes △5-3β and 17β-HSD, acid phosphatase in testis, prostate and seminal vesicle. There was a significant elevation in the activities of adrenal △5-3β-HSD, alkaline phosphatase in testis and other accessory sex organ in noise exposed group. Gonadosomatic, prostatosomatic and seminal vesiculo-somatic indexes were decreased significantly in noise exposed group. Therefore, it is evident that noise exposure at 85dB exerts a deleterious effect on testicular and adrenocortical activities.  相似文献   
82.
Fluid from cystic hygromata can be distinguished from amniotic fluid by measurement of alkaline phosphatase (ALP) isoenzymes. The former has a serum-type ALP, made up largely of the liver/bone/kidney isoenzyme and virtually no intestinal isoenzyme. Second trimester amniotic fluid ALP contains approximately 80 per cent intestinal isoenzyme.  相似文献   
83.
以文昌鱼为研究对象,研究了在六溴环十二烷暴露下对文昌鱼造成的机体氧化损伤.通过检测相关酶活变化情况,如酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD),从而确定低剂量长期暴露HBCD对文昌鱼鱼体产生氧化损伤效应的机制.急性毒性实验结果表明,文昌鱼暴露于六溴环十二烷饱和溶液(8....  相似文献   
84.
观察了不同浓度(10、20、40和80 μg/L)重金属离子Cu~(2+)和Zn~(2+)对日本新糠虾存活、蜕皮、蛋白含量和体内磷酸酶(碱性磷酸酶和酸性磷酸酶)活性的慢性(30 d)影响.结果显示:(1)Cu~(2+)和Zn~(2+)能明显降低糠虾存活率,金属离子浓度增高,存活率降低,其中Cu~(2+)引起的存活率降低更为明显,在最高浓度(80 μg/ L)Cu~(2+)组中糠虾的存活率仅为同浓度Zn~(2+)组的1/3,两组均明显低于对照组(P<0.05);Cu~(2+)和Zn~(2+)能明显降低糠虾蜕皮次数,最高浓度(80 μg/ L)Cu~(2+)和Zn~(2+)中糠虾的蜕皮数分别为11.00±1.73(次)和11.33±0.58(次),分别约为对照组的55.92%和57.6%.(2)Cu~(2+)和Zn~(2+)均能明显影响糠虾蛋白含量,其中Cu~(2+)的影响力更强,最高浓度(80 μg/ L)Cu~(2+)组糠虾体内蛋白白含量占湿重比为9.78%,仅约为对照组的1/2.(3)Cu~(2+)和Zn~(2+)能明显抑制糠虾体内两种磷酸酶的活力,碱性磷酸酶和酸性磷酸酶活力能作为糠虾监测环境重金属污染(Cu~(2+)和Zn~(2+))的检测指标.  相似文献   
85.
Industrial pollutions are responsible for alterations in biogeochemical cycling of phosphorus (P) in freshwater systems. The objectives of the present study were to quantify the major P forms and assess the relationship between P fractions in water and surface sediments of Govind Ballabh Pant Sagar (GBPS) reservoir, India. Surface water samples (n?=?48) and surface sediment samples (n?=?48) were collected from six regions of GBPS reservoir in December 2014. The results showed that total particulate phosphorus (TPP) and total dissolved phosphorus (TDP) account for 45%–58% and 42%–55% of total phosphorus (TP) in the surface water. The authigenic-P was found to be more than 84% of the total P in surface sediments. The TPP showed a positive statistical relationship with sedimentary P fractions (authigenic-P, exch-P, and organic-P) indicated the impact of industrial pollution load on inorganic and organic P fractions in water and sediments of GBPS reservoir. The discriminant fraction analysis (DFA) revealed that the exch-P, Fe(III)-bound-P, detrital-P, organic-P, and TPP were sensitive indicators of P dynamics in the industrially polluted GBPS reservoir.  相似文献   
86.
土壤水分对稻田土壤有效砷及碱性磷酸酶活性影响   总被引:1,自引:0,他引:1  
采用室内模拟方法,在35%、65%和110%最大饱和持水量(WHC)条件下,系统地分析了稻田土壤有效砷及碱性磷酸酶活性变化规律.结果表明:砷污染稻田土壤后有效砷含量随砷污染浓度增加而增大,随培养时间延长逐渐降低,15d后趋于稳定;淹水降低了土壤有效砷含量及碱性磷酸酶活性;采用U=A/(1+B×C)模型较好拟合了不同水分下土壤碱性磷酸酶活性(U)与砷浓度(C)关系,表明碱性磷酸酶活性在一定程度上可表征不同水分下稻田土壤砷污染程度;计算得到稻田土壤砷轻度污染临界浓度(ED10)为总砷67mg/kg和有效砷11mg/kg.研究表明适当调控土壤水分含量是控制稻田土壤砷毒性的有效方法之一.  相似文献   
87.
The aim of this study was to evaluate the effect of short-term consumption of oil and frying oil extracted from falafel patties, and then to study the long-term effect of consumption of falafel patties on rat liver gross morphology and serum liver enzymes. The frying oil quality was assessed using thiobarbituric acid reaction on rat liver homogenate. Frying oil and oil extracted from falafel patties were administered to male Wistar albino rats via gavage for 5 days. Blood samples were collected and the activities of alkaline phosphatase (ALP), aspartate aminotransferase, alanine aminotransferase (ALT), and bilirubin levels were determined. Livers were weighed and gross morphology was assessed. For the long-term effect of falafel consumption, rats were fed falafel patties for 30 days, and then blood samples were collected and assayed for the above-mentioned parameters. Short-term consumption of falafel extracts and frying oil did not cause any significant difference in the liver function tests and liver gross morphology. Whereas, long-term consumption of falafel patties caused a significant increase in ALP, ALT, bilirubin level and increased liver weight/body weight ratio denoting hepatotoxicity. This indicates that consumption of large amounts of falafel on daily basis might lead to hepatotoxicity.  相似文献   
88.
Ovarian hormones affected some enzymes in reproductive tissues. Previous studies revealed Anethum graveolens (dill) seed extract elevated ovarian hormones. In this study, we compared the effects of dill seed and leaf extracts on some enzymes activities and infertility potential. Female Wistar rats were divided into three groups of control, dill seed and dill leaf aqueous extracts treated groups. Experimental groups received 1 mL of 0.5 g kg?1 of each extract orally for 25 days (five estrous cycles). Estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone concentrations were determined. Uterus and ovaries were removed and their glucose-6-phosphate dehydrogenase, lactate dehydrogenase, and alkaline phosphatase activities were measured. Female rats of three groups were mated with untreated males. Fetuses were extracted in the 20th gestational day and their weights and crown rump lengths were measured. Anti-fertility and anti-implantation activities and fertility indices were calculated. Glucose-6-phosphate activity of dill seed treated group increased 1.6 times in the endometrium and 1.7 times in the myometrium. Progesterone concentration and lactate dehydrogenase activity of serum increased in the dill seed treated group compared to the control and dill leaf treated group. A significant decrease was observed in weights and crown rump lengths of fetuses, weights of placenta, and fertility index of the dill seed treated group compared to the control and dill leaf treated group, but its anti-implantation and anti-fertility indices increased. We suggested that high level of glucose-6-phosphate could entail increased oxidative stress in uterus and ovary. High lactate dehydrogenase activity in serum may affect cell membranes. Higher secretion of progesterone caused hormonal imbalance and produced estrous cycle irregularity. It was concluded that dill seed but not dill leaf extract could induce infertility in an animal model.  相似文献   
89.
磷酸酶在磷循环中占有重要地位 ,对植物有着非常重要的意义。根据几十年的国内外资料 ,本文概述了重金属、农药、酸沉降以及其他各种外来污染物对土壤磷酸酶的影响 ,并探讨了磷酸酶作为表征土壤污染程度的指标的可行性。土壤磷酸酶与各种污染物的相互作用关系在环境中的应用方面还需进一步研究。  相似文献   
90.
In recent decades, biodegradation has been considered a promising and eco-friendly way to eliminate organophosphorus pesticides (OPs) from the environment. To enrich current biodegrading-enzyme resources, an alkaline phosphatase (AP3) from Bacillus amyloliquefaciens YP6 was characterized and utilized to test the potential for new applications in the biodegradation of five broad-spectrum OPs. Characterization of AP3 demonstrated that activity was optimal at 40?°C and pH 10.3. The activity of AP3 was enhanced by Mg2+, Ca2+, and Cu2+, and strongly inhibited by Mn2+, EDTA, and L-Cys. Compared to disodium phenyl phosphate, p-nitrophenyl phosphate (pNPP) was more suitable to AP3, and the Vm, Km, kcat, kcat/Km values of AP3 for pNPP were 4,033?U mg?1, 12.2?mmol L?1, 3.3?×?106 s?1, and 2.7?×?108 s?1mol?1L, respectively. Degradation of the five OPs, which included chlorpyrifos, dichlorvos, dipterex, phoxim, and triazophos, was 18.7%, 53.0%, 5.5%, 68.3%, and 96.3%, respectively, after treatment with AP3 for 1?h. After treatment of the OP for 8?h, AP3 activities remained more than 80%, with the exception of phoxim. It can be postulated that AP3 may have a broad OP-degradation ability and could possibly provide excellent potential for biodegradation and bioremediation in polluted ecosystems.  相似文献   
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