血浆B型脑钠肽对心力衰竭和呼吸困难的诊断价值

目的：探讨血浆脑钠肽（BNP）水平在心力衰竭（CHF）T和呼吸困难诊断中的应用。方法：采用免疫荧光快速测试法测定56例已确诊心衰患者、40例心源性呼吸困难患者、29例肺源性呼吸困难患者和30例健康人血浆BNP的含量。结果：心衰组患者血浆BNP水平明显高于对照组,差异显著（P〈0．01）;心源性呼吸困难组患者的BNP值水平（1032．2±879．8pg／ml）与肺源性呼吸困难组患者的BNP值水平（67．1±43．6pg／ml）比较有显著性差异（P〈0．01）。结论：检测BNP水平可为临床诊断CHF及心源性与肺源性呼吸困难的鉴别诊断提供重要依据。     

慢性充血性心力衰竭血浆血管活性水平及临床意义

目的:探讨慢性心力衰竭患者血浆B型利钠肽(BNP)、心钠素(ANF)、胱抑素C(CysC)的水平及临床意义。方法:选择70例CHF患者,按NA分级;20例健康者作为对照。采用放射免疫法检查BNP和ANF水平;采用免疫比浊法检查Cys C。比较不同心衰等级以及不同BNP水平的上述指标的变化。结果:CHF患者血浆BNP、ANF、CysC水平与对照比较显著升高(P<0.05),并随NYHA等级增高而升高(P<0.05)。与BNP<400pg/ml组比较,400pg/ml≤BNP<800pg/ml组和BNP≥800pg/ml组心力衰竭患者Cr、BUN水平显著增高(P<0.05);相反地,HDL水平显著降低。结论:血浆B型利钠肽(BNP)、心钠素(ANF)及胱抑素C参与了CHF的发生发展过程,联合测定其含量的变化,对CHF患者的诊断、评估及危险分层具有一定的临床意义。     

心力衰竭患者MPV的水平及其与BNP 的相关性研究

目的:探讨心力衰竭患者血小板平均体积(MPV)的水平及其与B型钠尿肽(BNP)的相关性。方法:选取2013年10月到2015年10月入住南京鼓楼医院心内科的患者294例,分为非心力衰竭组(n-HF)92例、慢性心力衰竭组(CHF)69例、急性心力衰竭组(AHF)133例,回顾性分析其MPV、血小板计数(PLT)、BNP等数据。结果:AHF组BNP(1298.43±856.25 pg/m L)、CHF组BNP(198.54±118.72 pg/m L)均明显高于n-HF组(88.91±76.93 pg/m L)(P0.05),且AHF组BNP显著高于CHF组(P0.05);AHF组MPV(11.37±0.91 f L)与CHF组MPV(11.21±1.18 f L)均明显高于n-HF组(10.70±1.05 f L)(P0.05),但AHF组与CHF组MPV相比没有统计学差异(P=0.532)。将AHF组与CHF组合并为心衰(HF)组,其BNP(922.72±920.55 pg/m L)及MPV(11.31±1.01 f L)明显高于n-HF组(P0.05)。MPV与BNP的相关系数r=0.257,相关程度极弱。结论:心力衰竭患者MPV明显高于非心衰者,提示MPV水平可能有助于心力衰竭的诊断,但MPV与BNP基本不相关,且MPV在急性心力衰竭者与慢性心力衰竭者中没有差异。     

rhBNP治疗射血分数保留急性心力衰竭的临床研究

目的:探讨重组人脑利钠肽(rh BNP)对急性射血分数保留心力衰竭的临床治疗作用。方法:选择2008年6月至2014年6月间我院收治的20例急性射血分数保留心力衰竭患者为研究对象,其中10例予以硝普钠静脉注射48小时,10例予以rh BNP静脉注射48小时。48小时后,评估和比较两组患者心力衰竭的临床改善情况;72小时后,复查和比较两组患者血浆NT-pro BNP的下降值。结果:硝普钠组患者呼吸困难缓解积分(1.4±1.35)明显低于rh BNP组(3.5±0.71),rh BNP组呼吸困难缓解时间(3.68±1.69 h)显著短于硝普钠组(21.50±18.43 h),血浆NT-pro BNP浓度下降值(864.60±585.92 pg/ml)明显高于硝普钠组(423.30±284.06 pg/ml)。结论:rh BNP治疗急性射血分数保留心力衰竭的临床疗效优于硝普钠。     

老年男性慢性心衰患者在标准化抗心衰治疗后血浆脑利钠肽水平的分布及其影响因素

目的:探讨老年男性慢性心衰患者在经过标准化抗心衰治疗后的血浆脑利钠肽水平的分布及其影响因素.方法:选取我院高干病房心内科65例老年男性慢性心衰患者,收集患者一般资料、入院后检查结果及药物治疗情况,包括:年龄、有无心衰相关性疾病(高血压、糖尿病、冠心病、肾功能不全)、入院时心率、血压,入院后血肌酐、电解质、胸片有无肺淤血、超声心动图指标(ESV,EDV,EF)、出院前血浆BNP水平以及住院期间的药物治疗情况(主要指β-受体阻滞剂,ACEI或者ARB,强心剂、利尿剂等).住院期间给予标准化抗心衰治疗并在出院前检测血浆BNP水平,按BNP水平将患者分成高BNP组(BNP＞463 pg/ml)和正常BNP组(BNP≤ 463 pg/ml),比较两组间各研究因素分布有无差异,并对BNP水平与各因素之间的相关性进行统计分析.结果:经过标准化抗心衰治疗,出院时高BNP组患者44例(67.69％),这部分患者更多的伴有血压低、心率快、高肺动脉压、肺淤血的胸片表现.同时还发现高BNP组的患者中房颤及冠心病的发病率也偏高.对BNP的影响因素进行多元线性回归分析后得出房颤、低收缩压、肺淤血、高肌酐为出院时高BNP水平的影响因素.结论:在不同BNP分组中多个研究因素的分布有显著统计学差异,提示老年男性慢性心衰患者伴有低血压、房颤、高肌酐、肺淤血是出院时高血浆BNP的危险因素,需要给予密切的医疗关注和治疗.     

慢性充血性心力衰竭血浆血管活性水平及临床意义

目的：探讨慢性心力衰竭患者血浆B型利钠肽（BNP）、心钠素（ANF）、胱抑素C（CysC）的水平及临床意义。方法：选择70例CHF患者,按NYHA分级;20例健康者作为对照。采用放射免疫法检查BNP和ANF水平;采用免疫比浊法检查CysC。比较不同心衰等级以及不同BNP水平的上述指标的变化。结果：CHF患者血浆BNP、ANF、CysC水平与对照比较显著升高（P〈0．05）,并随NYHA等级增高而升高（P〈0．05）。与BNP〈400pg／ml组比较,400pg／ml≤BNP〈800pg／ml组和BNP≥800pg／ml组心力衰竭患者Cr、BUN水平显著增高（P〈0．05）;相反地,HDL水平显著降低。结论：血浆B型利钠肽（BNP）、心钠素（ANF）及胱抑素c参与．了CHF的发生发展过程．联合测定箕合号的变化．对CHF患者的诊断、评估及詹．险分层具有一定的临床意义．     

血清标志物联合检测在急性冠状动脉综合征诊断中的应用

目的:探讨血清cTnⅠ、CK-MB、MYO及BNP联合检测在急性冠状动脉综合征诊断中的临床价值。方法:选择临床及冠状动脉造影明确诊断的ACS患者76例,稳定性心绞痛患者32例,同期选择35例健康体检者作实验对照组;应用免疫化学发光法分别检测患者血清中cTnⅠ、CK-MB、MYO及BNP水平,采用受试者工作特征曲线(ROC)评价各指标的敏感度、特异度,并分析4项指标联合检测的诊断价值。结果:ACS组血清cTnⅠ、CK-MB、MYO及BNP水平分别为(9.27±7.25)μg/L、(239.50±213.27)ng/ml、(37.06±21.60)ng/ml、(632.11±293.20)pg/ml;AS组分别为(1.32±0.57)μg/L、(63.34±31.02)ng/ml、(19.48±8.04)ng/ml、(125.20±6.57)pg/ml;对照组为(0.17±0.06)μg/L、(30.02±15.23)ng/ml、(14.06±3.19)ng/ml、(47.52±21.30)pg/ml;ACS组患者血清cTnⅠ、CK-MB、MYO及BNP水平及阳性率均高于SA组和健康对照组,组间差异有统计学意义(P0.05);cTnⅠ的ROC曲线下面积(AUC)为(0.917±0.025),高于BNP曲线下面积(0.823±0.031)(P=0.037);4项指标联合检测ACS患者的敏感度(92.3%),高于单项检测86.0%(P0.05)。结论:检测血清cTnⅠ、CK-MB、MYO及BNP对于判定心肌缺血和损伤程度有重要价值,各项指标之间有互补作用,联合检测可为ACS早期诊断提供参考依据。     

妊娠高血压外周血中促Th2 的细胞因子水平及IL-2/IL-10 平衡 的临床意义

目的:检测妊娠高血压患者外周血中促Th2的分子IL-4、IL-2与IL-10的水平,探讨IL-2/IL-10在妊高症中的临床意义。方法:选择40例未妊娠妇女为对照组,30例正常妊娠妇女为妊娠组,28例妊娠高血压患者为妊娠高血压组,ELISA检测血清中IL-4、IL-2和IL-10的水平。结果:与对照组外周血中IL-4水平(0.53±0.04)pg/ml相比:正常妊娠组IL-4水平升高至(0.91±0.03)pg/ml(P<0.05),妊娠高血压组IL-4水平(0.67±0.35)pg/ml升高但明显低于正常妊娠组(P<0.01)。与对照组外周血中IL-2水平(0.41±0.05)pg/ml相比:正常妊娠组IL-2水平升高至(0.82±0.11)pg/ml(P<0.01);妊娠高血压组IL-2水平高达1.57±0.22(pg/ml)明显高于其它两组(P<0.01)。妊娠高血压组外周血中IL-10水平明显低于正常妊娠组IL-10水平(P<0.01);妊娠高血压组外周血中IL-2/IL-10比值明显高于于对照组及正常妊娠组的比值。结论:妊娠高血压患者外周血中细胞因子IL-2和IL-10分泌异常且诱导Th2细胞产生的IL-4降低,打破Th1/Th2平衡,致使Th1型免疫反应增强,使早孕期滋养细胞受到免疫损伤以致侵入能力下降,导致妊娠期高血压疾病的发生。     

非ST段抬高急性冠脉综合征患者心衰程度与血浆IL-15水平的相关性研究

目的:分析非ST段抬高急性冠脉综合征(NSTE-ACS)患者心衰程度与血浆IL-15水平的相关性及其临床意义。方法:选择NSTE-ACS不伴心衰及NSTE-ACS伴心衰住院患者154例,对照组为冠脉造影排除冠心病诊断者20例。冠脉造影前,采用ELISA法测定和比较各组的血浆IL-15水平,通过pearson相关检验分析血浆IL-15水平与NSTE-ACS患者心衰程度的相关性;散点图及拟合曲线观察血浆IL-15水平与NSTE-ACS患者心衰程度的关系;多元线性回归对差异变量进行调整,进一步明确血浆IL-15水平与NSTE-ACS患者心衰程度的关系。结果:NSTE-ACS不伴心衰组和NSTE-ACS伴心衰组患者的血清IL-15水平均显著高于正常对照组(P0.01);且NSTE-ACS伴心衰组的患者血清IL-15水平较NSTE-ACS不伴心衰组患者显著升高,差异具有显著统计学意义(P0.01)。Pearson检验结果显示血浆IL-15水平与EF值呈负相关(r=-0.775),与血清BNP水平呈正相关(r=0.474);散点图显示IL-15能与EF值线性拟合,呈负相关;散点图显示IL-15与血清BNP水平线性拟合,呈正相关;多元线性回归调整差异变量,明确IL-15与EF值(β=-0.295)呈显著相关。结论:NSTE-ACS患者的血浆IL-15水平与其心衰严重程度呈正相关。     

血浆脑源性神经营养因子水平与酒依赖患者认知功能的研究

目的:研究酒依赖患者与正常对照者之间血浆脑源性神经营养因子(BDNF)水平的差异;研究酒依赖患者认知功能与血浆BDNF水平的关系.方法:纳入符合美国精神障碍诊断与统计手册第四版(DSM-Ⅳ)酒依赖诊断标准的酒依赖患者38例和正常对照30例,应用威斯康星卡片分类测验(WCST)和理解记忆测验评定入组对象的认知功能,并应用酶联免疫吸附试验(ELISA法)检测血浆BDNF水平,统计方法采用t检验、秩和检验和直线相关分析.结果:酒依赖患者组血浆BDNF水平低于对照组[(3138.79± 1195.38)pg/ml与(3656.03± 899.56)pg/ml,P＜0.05].酒依赖患者组威斯康星卡片分类测验(WC ST)中的正确数和完成分类数的得分低于对照组,有统计学差异(P＜0.01);而错误数、持续性错误数、随机错误数均高于对照组,差异有统计学意义(P＜0.01).患者组理解记忆得分低于对照组(P＜0.01).患者组血浆BDNF水平与以下指标呈正相关:威斯康星卡片分类测验中的正确数(r=0.90755,P＜0.0001)、完成分类数(r=0.78427,P＜0.0001);理解记忆得分(r=0.48340,P=0.0021);患者组血浆BDNF水平与以下指标呈负相关:威斯康星卡片分类测验中的错误数(r=-0.90883,P＜0.0001)、持续性错误数(r=-0.82513,P＜0.0001)、随机错误数(r=-0.75373,P＜0.0001).结论:(1)本组酒依赖患者血浆BDNF水平低于正常;(2)本研究提示酒依赖患者认知功能损害程度越重其血浆BDNF水平就越低.     

Tuning of electronic properties of one-dimensional cyano-bridged Cu-Ni, Cu-Pd, and Cu-Pt bimetallic assemblies by stereochemistry of ligands

Preparations, XPS and electronic spectroscopy, and magnetism of seven new one-dimensional cyano-bridged coordination polymers, chiral [Cu(RR-chxn)₂][Pd(CN)₄] · 2H₂O (1), [Cu(trans-chxn)₂][M(CN)₄] · 2H₂O (2, 4, and 6 for M = Pd, Ni, and Pt), and [Cu(cis-chxn)₂][M(CN)₄] · 2H₂O (3, 5, and 7 for M = Pd, Ni, and Pt) (RR-chxn = cyclohexane-(1R,2R)-diamine, trans-chxn = racemic trans-cyclohexane-(1,2)-diamine, and cis-chxn = racemic cis-cyclohexane-(1,2)-diamine) have been reported in view of tuning of their electronic properties by stereochemistry of chxn ligands and metal-substitution. Comparison of Cu 2p_1/2 and 2p_3/2 peaks of XPS and broad d-d bands around 18 000 cm⁻¹ of electronic spectra are described systematically for 1-7. Variable-temperature magnetic measurement shows that complexes 1-7 indicate weak antiferromagnetic interactions via cyano-bridges. Because of semi-coordination coupled with pseudo Jahn-Teller elongation and electrostatic interaction for 1, the axial Cu-N coordination bond distances of 2.330(7) and 3.092(8) Å are considerably longer than those of equatorial ones in the range from 2.016(6) to 2.030(6) Å. The former bond distances of 1 are intermediate values among the related Ni (2.324(6) and 3.120(8) Å) and Pt (2.34(1) and 3.09(1) Å) complexes.     

Structure and function of S-adenosylhomocysteine hydrolase

In mammals, S-adenosylhomocysteine hydrolase (AdoHcyase) is the only known enzyme to catalyze the breakdown of S-adenosylhomocysteine (AdoHcy) to homocysteine and adenosine. AdoHcy is the product of all adenosylmethionine (AdoMet)-dependent biological transmethylations. These reactions have a wide range of products, and are common in all facets of biometabolism. As a product inhibitor, elevated levels of AdoHcy suppress AdoMet-dependent transmethylations. Thus, AdoHcyase is a regulator of biological transmethylation in general. The three-dimensional structure of AdoHcyase complexed with reduced nicotinamide adenine dinucleotide phosphate (NADH) and the inhibitor (1′R, 2′S, 3′R)-9-(2′,3′-dihyroxycyclopenten-1-yl)adenine (DHCeA) was solved by a combination of the crystallographic direct methods program, SnB, to determine the selenium atom substructure and by treating the multiwavelength anomalous diffraction data as a special case of multiple isomorphous replacement. The enzyme architecture resembles that observed for NAD-dependent dehydrogenases, with the catalytic domain and the cofactor binding domain each containing a modified Rossmann fold. The two domains form a deep active site cleft containing the cofactor and bound inhibitor molecule. A comparison of the inhibitor complex of the human enzyme and the structure of the rat enzyme, solved without inhibitor, suggests that a 17° rigid body movement of the catalytic domain occurs upon inhibitor/substrate binding.     

Influence of Fluoride on Rat Kidney Antioxidant System: Effects of Methionine and Vitamin E

The aim of the study has been to determine and compare the influence upon the kidney antioxidative system, exercised by administration of vitamin E, and vitamin E in combination with methionine, under conditions of oxidative stress induced by sodium fluoride. The experiment was carried out on Wistar FL rats (adult males) that, for 35 days, were administered water, NaF, NaF with vitamin E, or vitamin E with methionine (doses: 10 mg NaF/kg of body mass/24 h, 3 mg vitamin E per 10 μl per rat for 24 h, 2 mg methionine per rat for 24 h). The influence of administered sodium fluoride and antioxidants upon the antioxidative system in kidney was examined by analyzing the concentration of malondialdehyde (MDA) and the activity of the most important antioxidative enzymes (SOD, total and both its isoenzymes, GPX, GST, GR, and CAT). The studies carried out confirmed the disadvantageous effect of the administered dose of NaF upon the antixodiative system in rats (increase in the concentration MDA, decrease activity of all antioxidative enzymes). The administration of vitamin E increased the activity of studied enzymes with the exception of glutathione reductase GR; it also reduced the procesess of lipid peroxidation. It has been found that combined doses of vitamin E and methionine were most effective in inhibiting lipid peroxidation processes. The results confirmed the antioxidative properties of methionine.     

Reorientation of Microfibrils and Microtubules at the Outer Epidermal Wall of Maize Coleoptiles During Auxin-Mediated Growth

Auxin-mediated elongation growth of isolated subapical coleoptile segments of maize (Zea mays L.) is controlled by the extensibility of the outer cell wall of the outer epidermis (Kutschera et al., 1987). Here we investigate the hypothesis that auxin controls the extensibility of this wall by changing the orientation of newly deposited microfibrils through a corresponding change in the orientation of cortical microtubules. On the basis of electron micrographs it is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface. Conversely, reinduction of growth by exogenous auxin is correlated with a relative increase of transversely orientated microfibrils and microtubules at the inner wall surface. These changes can be detected 30–60 min after the removal and addition of auxin, respectively. The functional significance of directional changes of newly desposited wall microfibrils for the control of elongation growth is discussed.     

Land,livestock, and livelihoods: Changing dynamics of gender,caste, and ethnicity in a Nepalese Village

Over the past 10 years, Ghusel VDC, Lalitpur District has moved from primarily subsistence agriculture into the wider cash economy aided by the Small Farmers' Development Program (SFDP), which provides credit to farmers mainly for the purchase of buffalo for milk production, and by the National Dairy Corporation, which supports local dairy cooperatives. Analysis reveals that buffalo-keeping and milk sales are increasing the well-being of many households, while at the same time creating new inequalities in gender roles and responsibilities, greater inequities between Brahmin and Tamang residents in Ghusel, and placing pressures on the ecosystem for increased supplies of fodder and fuelwood. Evidence suggests that there is critical, need for attention to the social, and particularly gender-based, implications of maintaining livestock for milk sales and to the ecological underpinnings of this livelihood system.     

Chiral Separation of G‐type Chemical Warfare Nerve Agents via Analytical Supercritical Fluid Chromatography

Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G‐type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical‐scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(–) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(–) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. Chirality 26:817–824, 2014. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc.     

In vitro studies of the rabbit immune system. IV. Differential mitogen responses of isolated T and B cells.

The mitogenic responses of separated rabbit lymphocyte populations functionally analogous to mouse T and B cells have been tested in vitro. Purified T cells were prepared by passage over nylon wool (NW) and purified B cells prepared by treatment with antithymocyte serum and complement (ATS + C). ATS + C kills 70% of peripheral blood lymphocytes (PBL's) and 50% of the spleen cells while passage over NW yields 40% of the applied PBL's and 5–23% of the applied spleen cells. NW-purified T cells from the spleen or PBL's respond fully to concanavalin A (Con A) but have a reduced response to phytohemaglutinin (PHA) and little or no response to goat anti-rabbit immunoglobulin (anti-Ig). PBL's that survive ATS + C (B cells) are stimulated by anti-Ig but not by Con A or PHA. B cells purified from spleen do not respond to Con A or PHA but will respond to anti-Ig under appropriate conditions. A full spleen B-cell response to anti-Ig required removal of Ig produced by the cultures that blocked anti-Ig stimulation. It is concluded that, for rabbit lymphocytes, Con A and PHA are primarily T-cell mitogens and that anti-Ig is primarily a B-cell mitogen. However, the mitogen response of unfractionated PBL or spleen cell populations indicates an overlap in reactivity. This could be due to cells sharing T and B properties, alteration of cell populations by the fractionation procedures used, or recruitment of one population in the presence of a mitogenic response of the other population.     

邻苯二甲酸二丁酯对翡翠贻贝抗氧化酶及脂质过氧化水平的影响

实验室条件下,研究了不同浓度邻苯二甲酸二丁酯(DBP)长期胁迫(15 d)对翡翠贻贝内脏团和外套膜抗氧化酶(超氧化物歧化酶SOD、过氧化氢酶CAT)及脂质过氧化(LPO)水平(以MDA含量表示)的影响,以及受胁迫翡翠贻贝在清洁海水中恢复阶段上述生化指标的变化特征.结果表明:胁迫阶段,0.5和2.5 mg.L-1DBP下翡翠贻贝内脏团SOD活性表现为先抑制后逐渐恢复,12.5和62.5 mg.L-1下则持续受到显著抑制;不同浓度组CAT活性均明显被抑制.LPO水平明显升高.外套膜中,2.5 mg.L-1下SOD活性受到持续诱导,其他浓度组则先被抑制,后随曝露时间延长逐渐被诱导;各浓度组CAT的变化波动较大,没有明显规律;而LPO水平明显升高.净化恢复阶段,12.5和62.5 mg.L-1DBP胁迫下的内脏团SOD和CAT活性恢复较慢,其LPO水平随时间延长逐渐恢复至对照组水平;外套膜中SOD活性呈持续升高趋势,CAT活性和LPO水平则随时间延长恢复到对照组水平.     

多马胺能药物对鲇鱼促性腺激素（GtH）分泌活动的影响

以珠江流域鲇鱼（silurus asotus)为实验材料,研究了多巴胺（DA）能药物（DA及其D－2型受体拮抗物 ,DOM）对鲇鱼促性腺激素（GtH)释放的影响,结果表明,在性腺发育的各个时期,单独注射DOM（5ug/g)均不能显著提高鲇鱼血液基础GtH水平,当DOM与LHRH－A联合注射时能显著增强LHRH－A刺激GtH释放的作用;DA只能抑制GnRH诱导的GtH释放,对基础GtH释放无抑制作用,这种生殖内分泌调节方式与鲇形目的革胡子鲇（Clarias gariepinus)和大鳍Hu（Mystus macropterus)相似,而与鲤形目的鲁科（Cyrpindiae)鱼类不同。     

X-ray induction of dominant lethals in late spermatids and mature spermatozoa of Drosophila melanogaster: the role of oxygenation

The role of oxygenation in determining the sensitivity to the induction of dominant lethals was examined in late spermatids and mature spermatozoa of Drosophila melanogaster. 0–2-h-old or 7-day-old Oregon-K males were irradiated with different X-ray exposures in nitrogen, air or in oxygen and the frequencies of dominant lethals induced in these stages were studied. The results obtained confirm and extend Sobels' earlier observations and the interpretation derived therefrom namely, that under normal conditions in air, mature spermatozoa are characterised by a higher degree of oxygenation than late spermatids and this difference is sufficient to explain the differential response of these stages. Similar Oxygen-Enhancement-Ratios(OERs) (of about 2) were obtained for both the cell stages. The present data also revealed that late spermatids are significantly less sensitive than mature spermatozoa to the X-ray-induction of dominant lethals in a nitrogen atmosphere. A plausible mechanism is suggested to explain this observation.