褪黑素对中国绒山羊在非生绒期促绒生长与绒产量的影响

用简易的外科手术对阿白羊,盖县红山羊及二者杂交改良型绒山羊在梳绒后于其颈部皮下埋植一种含褪黑素的胶囊,经５周后受试羊群开始长绒,而对照群羊则未见绒生长。在９月中旬天然生绒开始时,受试群羊绒已分别长至３－５ｃｍ,,而对照群则刚开始生长至２ｃｍ。表明上述各受试群当年被成功地诱发二次生绒。     

褪黑素对绒山羊皮肤FGF5等绒毛生长相关基因的影响

目的:旨在分析埋植褪黑素后对绒山羊皮肤绒毛生长相关基因表达的影响,进而探讨褪黑素促绒毛生长的机理。方法:以内蒙古白绒山羊为研究对象,选取体况相近的4月龄母羔羊10只,按试验要求随机分为2组,处理组按照2mg/kg BW(体重)的剂量每两个月耳后皮下埋植褪黑素,对照组不埋植,试验时间为1年。实验开始后每月采集绒山羊体侧皮肤和毛样,利用荧光定量PCR技术检测9个绒毛生长相关基因的表达变化。结果:(1)埋植褪黑素后各个基因的平均表达水平都有所上调,其中显著上调FGF5(P<0.0001),而对β-catenin、MSX-2、Wnt10b、BMP2、BMPRIB、NTRK3、Delta1、hairless等无显著影响(P>0.05);(2)埋植褪黑素明显提高了FGF5与hairless的相关性,并且使FGF5与β-catenin、NTRK3的相关性由负相关变成正相关,与Wnt10b的相关性降低,FGF5与其余4个基因的相关性变化不大。结论:结果提示,褪黑素上调绒山羊皮肤FGF的表达,影响FGF5与hairless、β-catenin、NTRK3之间的相关性;山羊中FGF5基因对被毛表型的作用与其他动物不同;褪黑素对复杂组织和单个细胞的作用不同;MAPK信号通路是受褪黑素影响最大的一个信号途径。推测褪黑素可能通过调节绒山羊皮肤中RORα来发挥作用,影响FGF5与hairless、β-catenin、NTRK3和Wnt10b等的相关性,同时抑制MSX2和BMP2的功能,进而促进绒毛的生长。     

长期低浓度SO2对大豆生长和产量的影响

随着化石燃料消耗量不断增加,由此产生的主要大气污染物之一SO_2的浓度和影响范围也日趋增大。SO_2对植物,特别是对农作物的影响已受到普遍重视。本研究选择我国北方种植面积大、分布广的大豆为供试作物,在野外开顶式熏气装置中进行低浓度SO_2长期暴露试验,观察SO_2对大豆生长发育及产量的影响,以期为制订农田大气环境质量标准提供有一定参考价值的生态学基准。     

半干旱黄土高原地区地膜覆盖和底墒对春小麦生长及产量的影响

在年均降水量为415mm的半干旱地区黄绵土旱地上,以春小麦为供试作物进行大田实验,研究不同底墒(包括低底墒、中底墒和高底墒)下．地膜覆盖(包括不覆膜、播种后覆膜30d、覆膜60d和覆膜120d即全程覆膜)进程对作物生产的影响。结果表明．增加底墒和合理的覆膜进程均会显著增加作物的生长和产量,但底墒不同,其最佳覆膜进程不同：在低底墒时,覆膜处理反而使产量低于不覆膜处理;在中底墒时．覆膜30d产量最高,随着覆膜时间延长．产量呈下降趋势,甚至全程覆膜产量低于不覆膜处理;高底墒以覆膜60d产量最高。综合作物生长和产量,全程覆膜并没有多少实际意义。在同种覆膜处理下,随着底墒的增加,根生物量、地上干物质、叶面积及产量也增加显著,高底墒覆膜60d处理的产量在所有处理中为最高。     

叶面喷施褪黑素对低温胁迫下南瓜幼苗生长和生理特性的影响

以南瓜品种‘永安2号’幼苗为试验材料,采用室内盆栽实验,在叶面喷施不同浓度(0、50、100、150、200和300μmol·L^(-1))褪黑素(MT)后进行低温(10℃/7℃)胁迫处理,考察幼苗生长指标以及相对电导率、抗氧化酶活性、渗透调节物质含量等抗逆生理指标的变化,初步探讨外源褪黑素缓解南瓜幼苗低温冷害的生理机制。结果表明:(1)在低温胁迫条件下,南瓜幼苗出现叶片萎蔫失水、边缘失绿褪色、向内卷曲等冷害症状;幼苗株高、茎粗、鲜重、干重和壮苗指数等生长指标及叶片相对叶绿素含量均显著降低;叶片相对电导率、MDA含量和O^(-)·_(2)产生速率显著升高50%以上,超氧化物歧化酶、过氧化物酶、过氧化氢酶、抗坏血酸过氧化物酶、谷胱甘肽还原酶、脱氢抗坏血酸还原酶活性以及可溶性糖、可溶性蛋白和脯氨酸含量也大多显著升高。(2)与低温胁迫处理相比,叶面喷施不同浓度褪黑素后,南瓜幼苗叶片冷害症状均得到不同程度恢复,并以100μmol·L^(-1) MT处理生长状态最好,植株形态表型与对照已没有明显差异;幼苗生长指标以及叶片相对叶绿素含量、6种抗氧化酶活性、3种渗透调节物质含量均不同程度提高,并随着MT浓度升高均先升后降,且均在100μmol·L^(-1) MT处理最高。研究发现,外源褪黑素能通过提高叶片叶绿素含量、增强抗氧化酶活性、增加渗透调节物质积累,显著降低低温冷害造成的膜质过氧化程度,有效减轻低温胁迫对南瓜幼苗的伤害,增强其抵抗低温能力,恢复幼苗的正常生长,且喷施浓度为100μmol·L^(-1)时效果最佳。     

螯合铁肥对当归生长及产量品质的影响

目的:探讨螯合铁肥对当归生长及产量品质的影响.方法:采用单因素随机区组设计,设置螯合铁肥(乙二胺四乙酸铁钠)以4个浓度进行喷施,化肥设置常规施肥量作基肥移栽前土施,测定当归的生长指标、产量及品质.结果:螯合铁肥喷施浓度为900 ml/g时,当归生长指标及产量品质最佳.结论:多次喷施适宜浓度螯合铁肥可以促进当归生长,提高...     

不同土壤覆盖物对旱作水稻生长和产量影响

在四川盆地通过田间试验研究了不同覆盖物对旱作水稻植株生长及产量的影响。结果表明,在有效铁含量较高而有效锰含量较低的土壤上,覆盖地膜及传统淹水处理在整个生育期没有表现缺锰症,而覆盖麦秆处理前期分蘖能力差,生长缓慢,表现严重的缺锰症。在覆麦秆处理裂区灌施2‰的MnSO4溶液（每次450kg/hm^2）两次后,水稻株高、分蘖和生物量都迅速增加,说明覆麦秆处理水稻受到了锰的胁迫。其原因与地膜处理明显提高土壤温度,而覆麦秆处理却具有降温作用有关。试验还发现,灌施锰肥能够补偿温度降低所造成的不利影响,水稻产量以覆地膜处理最高,其次是覆秆灌锰处理,再是是传统淹水处理,覆麦秆未灌施锰肥处理产量最低,后与其它处理差异也达极显水平。覆地膜条件下,水稻产量随施氮量的提高而提高,但当施氮量为150kg/hm^2后产量变化不大。与传统淹水相比,覆盖旱作处理显降低总耗水量,节水率达63.1%;并在产量基本不变或有所提高的前提下,提高水分利用效率2－3倍。     

褪黑素在哺乳动物皮肤中的生物学功能及对山羊绒生长的调控作用

褪黑素(melatonin, MT)可促进山羊绒的生长,提高山羊绒的产量,增加养羊业的经济效益。本文阐述了哺乳动物皮肤中褪黑素的生物合成、代谢和功能,对褪黑素调控山羊绒生长的国内外研究进展进行了综述,对未来研究方向进行了展望,以期为绒山羊研究人员深入探索褪黑素促山羊绒生长的机理提供参考。     

温度对玉米生长和产量的影响

为了明确气温变化对玉米生长发育和产量的影响,建立玉米低温冷害监测和气象评估模式,在东北地区中部的榆树市进行了玉米分期播种试验。试验采用3个品种,设置早、中、晚3个播种期,进行玉米生长发育进程、叶面积指数、生物量、产量和温度等观测。结果表明：玉米的生长速率与温度密切相关,平均气温每升高1 ℃,出苗速率提升17%,营养生长速率提升5%;积温每增加100 ℃·d,玉米最大叶面积指数增加10%,最大生物量和产量增加8%;玉米生长发育期(日平均气温稳定>10 ℃期间)间平均气温降低0.7 ℃,或活动积温减少100 ℃·d,玉米成熟期将延迟7 d,发生一般低温冷害,玉米单产减少8%;气温下降1 ℃,或积温减少140 ℃·d,生育期延迟10 d,发生严重低温冷害,减产10%以上;在水分条件比较适宜的前提条件下,气候变暖对东北地区玉米单产提高是有利的。     

EFFECTS OF LIGHT AND MELATONIN TREATMENT ON BODY TEMPERATURE AND MELATONIN SECRETION DAILY RHYTHMS IN A DIURNAL RODENT,THE FAT SAND RAT

Many mammals display predictable daily rhythmicity in both neuroendocrine function and behavior. The basic rest-activity cycles are usually consistent for a given species and vary from night-active (nocturnal), those mostly active at dawn and dusk (i.e., crepuscular), and to day-active (diurnal) species. A number of daily rhythms are oppositely phased with respect to the light/dark (LD) cycle in diurnal compared with nocturnal mammals, whereas others are equally phased with respect to the LD cycle, regardless of diurnality/nocturnality. Pineal produced melatonin (MLT) perfectly matches this phase-locked feature in that its production and secretion always occurs during the night in both diurnal and nocturnal mammals. As most rodents studied to date in the field of chronobiology are nocturnal, the aim in this study was to evaluate the effect of light manipulations and different photoperiods on a diurnal rodent, the fat sand rat, Psammomys obesus. The authors studied its daily rhythms of body temperature (T_b) and 6-sulphatoxymelatonin (6-SMT) under various photoperiodic regimes and light manipulations (acute and chronic exposures) while maintaining a constant ambient temperature of 30°C?±?1°C. The following protocols were used: (A) Control (CON) conditions 12L:12D; (A1) exposure to one light interference (LI) of CON-acclimated individuals for 30?min, 5?h after lights-off; (A2) short photoperiod (SP) acclimation (8L:16D) for 3 wks; (A3) 3 wks of SP acclimation with chronic LI of 15?min, three times a night at 4-h intervals; (A4) chronic exposure to constant dim blue light (470nm, 30 lux) for 24?h for 3 wks (LL). (B) The response to exogenous MLT administration, provided in drinking water, was measured under the following protocols: (B1) After chronic exposure to SP with LI, MLT was provided once, starting 1?h before the end of photophase; (B2) after a continuous exposure to dim blue light, MLT was provided at 15:00?h for 2?h for 2 wks; (B3) to CON animals, MLT was given intraperitoneally (i.p.) at 14:00?h. The results demonstrate that under CON acclimation, Psammomys obesus has robust T_b and 6-SMT daily rhythms in which the acrophase (peak time) of T_b is during the photophase, whereas that of 6-SMT is during scotophase. LI resulted in an elevation of T_b and a reduction of 6-SMT levels. A significant difference in the response was noted between acute and chronic exposure to LI, particularly in 6-SMT levels, which were lower than CON after LI and higher after chronic LI, implying an acclimation process. Constant exposure to blue light abolished T_b and 6-SMT rhythms in all the animals. MLT administration resumed the T_b daily rhythm in these animals, and had a recovery effect on the chronic LI-exposed animals, resulting in a T_b decrease. Altogether, the authors show in this study the different modifications of T_b rhythms and MLT levels in response to environmental light manipulations. These series of experiments may serve as a basis for establishing P. obesus as an animal model for further studies in chronobiology. (Author correspondence: hagitsc@research.haifa.ac.il)     

内蒙古白绒山羊若干数量性状遗传参数的研究

本研究应用女母回归法、公畜内女母回归法、半同胞相关法和单元内半同胞相关法对内蒙古阿尔巴斯白绒山羊的产绒量、绒厚、毛长、体重、绒伸直长度和细度等六个性状的遗传参数进行了估测。结果表明：（1）绒量遗传力介于0.26～0.45之间;绒厚遗传力介于0.33～0.56之间;毛长遗传力介于0.23～0.32之间;体重的遗传力介于0.16～0.36之间;绒伸直长度遗传力为0.24;绒细度的遗传力为0.14。（2）产绒量与绒厚、绒厚与毛长、长度与绒厚、长度与毛长的遗传相关分别介于0.33～0.79、0.51～0.69、0.38～0.60、0.74～0.90之间,存在较强的正向遗传相关;绒量与毛长、绒量与体重、绒厚与体重、细度与绒厚、细度与绒量、细度与体重的遗传相关分别为0.11～0.38、0.06～0.17、0.15～0.36、0.02～0.11、0.24～0.35、0.13～0.32之间,存在较弱的正向遗传相关;毛长与体重、长度与绒量、长度与体重、长度与细度、细度与毛长之间的遗传相关介于-0.14～-0.28、-0.09～-0.20、-0.18～-0.23、-0.27～-0.31、-0.17～-0.28之间,存在中等偏弱的负向遗传相关。（3）绒量、绒厚、毛长、体重的重复率分别为0.42、0.27、0.59、0.18。 Abstract：Daughter-dam regression, daughter-dam regression wit hin sire, half-sib correlation and intro-unit half?sib correlation were used in the study to estimate genetic parameters for several traits of Albas type of In ner Mongolia cashmere goats, Traits included in this paper were cashmere yield ( CY),cashmere thickness(CT),staple length(SL),body eight(BW),cashmere stretched length(CSL) and cashmere fineness(CF).The results showed: (1)Heritabilities for CY,CT,SL and BW ranged between 0.26 and 0.45,between 0.33 and 0.56, between 0.23 and 0.32 and between 0.16 and 0.36 respectively; Heritabilities for SL and CF were 0.24 and 0.14 respectively.(2)Genetic correlations between CY and CT,between CT and SL ,between SL and CT and between CST and SL ranged 0.33～0. 79, 0.51～0.69, 0.38～0.60, and 0.74～0.90,respectively,and they belonged to high positive one;Genetic correlations between CY and SL, between CY and betw een CY and BW,between CT and BW, between CF and CT, between CF and CY and betwe en CF and BW ranged 0.11～0.38, 0.06～0.17,0.15～0.36, 0.02～0.11, 0.24 ～0.35 and 0.13～0.32,respectively, and they belonged to low positive correla tion;Genetic correlations between SL and BW, between SL and CY,between SL ?and BW, between? SL and CF and between CF and SL ranged -0.14～-0.28, -0.09～-0 .20, -0.18～-0.23,-0.27～-0.31,and -0.17～-0.28,respectively,and they belonged to low negative correlations.(3)Repeatabilities for CY,CT,SL and BW were 0.42,0.27,0.59 and 0.18,respectively.     

EFFECT OF LIGHT WAVELENGTH ON SUPPRESSION AND PHASE DELAY OF THE MELATONIN RHYTHM

Different wavelengths of light were compared for melatonin suppression and phase shifting of the salivary melatonin rhythm. The wavelengths compared were 660 nm (red), 595 nm (amber), 525 nm (green), 497 nm (blue/green), and 470 nm (blue). They were administered with light-emitting diodes equated for irradiance of 130 μW/cm². Fifteen volunteers participated in all five wavelength conditions and a no light control condition, with each condition conducted over two consecutive evenings. Half-hourly saliva samples were collected from 19:00 to 02:00 on night 1 and until 01:00 on night 2. Light was administered for the experimental conditions on the first night only from midnight to 02:00. Percentage melatonin suppression on night 1 and dim light melatonin onset (DLMO) for each night were calculated. The shorter wavelengths of 470, 497, and 525 nm showed the greatest melatonin suppression, 65% to 81%. The shorter wavelengths also showed the greatest DLMO delay on night 2, ranging from 27 to 36 min. The results were consistent with the involvement of a scotopic mechanism in the regulation of circadian phase. (Chronobiology International, 18(5), 801-808, 2001)     

外源性褪黑激素对中缅树()适应性产热特征的影响

注射外源性褪黑激素后,中缅树Ｑｕ体温明显降低,静止代谢率和非颤拦性产热显著增加,并随蝗延长增加的赵多,注射褪黑激素不能影响肝脏的褐色脂肪组织的重量,但两者线粒体蛋白含量显著增加、线粒体呼吸和细胞色素Ｃ氧化酶活性增加;褐色脂肪组织的α磷酸甘油氧化酶和Ｔ４５’－脱碘酶活性显著增加;血清Ｔ３浓度显著上升,Ｔ４浓度显著降低。结果表明,松果体褪黑激素参与了中缅树Ｑｕ的适应性产热调节。     

褪黑激素对D-半乳糖处理小鼠学习记忆和脑组织超氧物歧化酶活力的影响

采用Ｍｏｒｒｉｓ水迷宫法和ＮＢＴ法分别检测了褪黑激素对Ｄ－半乳糖处理小鼠的空间学习记忆能力和脑组织超氧物歧化酶活力的影响。结果表明,Ｄ－半乳糖对小鼠的逃避潜伏期无显著影响,但降低小鼠的穿环系数,还促使小鼠的脑组织超氧物歧化酶活力明显升高;褪黑激素可提高小鼠的空间学习记忆能力,降低Ｄ－半乳糖所引起的超氧物歧化酶活力升高。     

褪黑素对胃癌小鼠Survivin表达的影响

目的探讨褪黑素对胃癌小鼠Survivin表达的影响。方法选用6-8周龄SPF级615近交系小鼠,接种胃癌MFC细胞,建立荷瘤小鼠模型并给予不同剂量的褪黑素处理,用Real-time PCR法和Western blot法检测肿瘤组织中Survivin mRNA和蛋白的表达。结果 Real-time PCR和Western-blot检测显示褪黑素各干预组小鼠胃癌组织中Survivin基因的表达水平下降且随褪黑素剂量增大而降低。结论褪黑素具有下调survivin的作用。褪黑素降低survivin的表达,可能是褪黑素抑制肿瘤的作用机制之一。     

CIRCADIAN CONTROL OF MIGRATORY RESTLESSNESS AND THE EFFECTS OF EXOGENOUS MELATONIN IN THE BRAMBLING,FRINGILLA MONTIFRINGILLA

Circadian pacemakers control both “daytime” activity and nocturnal restlessness of migratory birds, and the daily rhythm of melatonin release from the pineal has been suggested to be involved in the control of migratory activity. To study the phase relations between the two activity components during entrainment and when free running, locomotor activity of bramblings (Fringilla montifringilla) was recorded continuously under a 12:12 “cool light” to “warm light” cycle (CL:WL, ca. 5000 K and ca. 2500 K, respectively) or blue light to red light cycle (BL:RL, maxima at 440 and 650 nm, respectively) at different irradiance ratios. Migratory activity was expressed primarily during the WL or RL phase of the light cycles. Under free-running conditions, the circadian periods τ correlated with the phase relations between day and night (migratory) activity components during preceding entrainment. Bramblings with migratory activity had significantly longer τ at constant light intensity than the same individuals without migratory activity. Birds with migratory activity reentrained faster after a 6h phase shift of the CL:WL cycle than birds without migratory activity. When exogenous melatonin was given in the drinking water (200 μg/mL 1% ethanol or 0.86 mM) to bramblings exposed to 12:12 CL:WL cycles with constant irradiance, the amounts of activity, which were initially higher during the WL phase of the light cycle, were suppressed to similar low levels during both light phases. The systematic changes in the amounts of activity during melatonin treatment were not correlated with consistent changes in entrainment status. The data support the hypothesis that changes in the amplitude and level of the daily melatonin cycle are involved in regulating migratory restlessness, by either allowing or inhibiting nocturnal activity. (Chronobiology International, 17(4), 471–488, 2000)     

外源性褪黑激素对黄鳝性腺发育及性腺激素分泌的影响

通过注射实验研究了外源性褪黑激素对黄鲜性腺发育及性腺激素分泌的影响。结果表明,处于不同性腺发育时期的黄鲜对餐源褪黑激素的反应存在季节性差异。上述结果暗示,黑激素影响黄鲜性腺发育的关键时间可能是在性腺静止期,亦即Ⅳ期或／和Ⅳ期之前。     

内蒙古西伯利亚棘球绦虫和多房棘球绦虫泡状蚴在小白鼠发育成熟的比较

本文报道人兽共患的泡状肝包虫病原,西伯利亚棘球绦虫Echinococcus sibiricensis (Rausch andSchiller, 1954)泡状蚴和多房棘球绦虫Ech inococcusmultilocularis ( Leuckart, 1863)泡状蚴在KM株小白鼠发育成熟过程比较观察的结果.此两虫种泡状蚴的发育成熟过程仍然和它们早期发育的规律(唐崇惕等,2001)相同.虽然它们成熟的泡囊都被着生在网状结构中的许多原头节所充满,但是在多房棘球绦虫9-14个月的泡状蚴,仍然可以见到它们的原头节和网状结构都是起源于泡囊囊壁内表面的胚细胞层,并且始终保持与该层的联系.而西伯利亚棘球绦虫泡状蚴在鼠肺脏或肝脏的各泡囊中的原头节和网状结构是由可移动的胚细胞团发育生成,它们与泡囊囊壁没有如前者样的联系.西伯利亚棘球泡状蚴在各别小白鼠肝脏也能发育成熟,但不正常,宿主反应异常强烈.