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1.
磁处理种子对羊草生长及抗盐碱性的影响   总被引:16,自引:6,他引:10  
利用磁场处理羊草(Leymus chinensis)种子,观测其对羊草生长的影响,将不同磁场处理的羊草苗进行盐(NaCl)碱(Na2CO3)混合胁迫处理,观测羊草的抗盐碱性。结果表明:磁场处理不仅明显提高了羊草的长势,相对生长率提高了20%左右,而且增强了对盐碱的抗性,在高浓度盐碱胁迫下不仅羊草长势好于对照,其抗性指标脯氨酸含量及SOD酶活性也明显提高。根据试验结果确定羊草的最佳磁处理参数为300mT,其次是200mT。  相似文献   

2.
碳酸钠胁迫对星星草种子萌发的影响   总被引:6,自引:0,他引:6  
星星草种子的发芽率、发芽指数、活力指数、幼苗生长势与所胁迫的Na2CO3浓度负相关极其显著。影响星星草种子累积发芽率的Na2CO3浓度的适宜值,临界值和极限值分别为0.82%、1.30%、2.16%,清水复萌实验表明,经较高浓度Na2CO3处理的种子仍具有较高的发芽潜能。表明星星草种子具有较强的抗盐碱性。  相似文献   

3.
磷素营养对星星草幼苗抗碱性的影响   总被引:2,自引:0,他引:2  
通过以不同水平磷素营养培养星星草幼苗,研究磷素营养对星星草幼苗抗碱性的影响,试验结果表明:在2.0%Na2CO2胁迫下星星草苗磷素营养的最适浓度为2.8mmol·L^-1KH2PO4,此条件下仅对株高,干重和鲜重的增长有促进作用,而且受害程度最小,对Na2CO3胁迫的缓解作用最强,在一定程度上可提高星星草幼苗对Na2CO3胁迫的抗性。  相似文献   

4.
鲁梅克斯K—1杂交酸模耐盐性的初步研究   总被引:3,自引:0,他引:3  
对鲁梅克斯K-1杂交酸模干种子,种子萌发,苗期及成株的耐盐性进行了研究,通过测定在不同Na2SO4和Na2CO3盐浓度胁迫下其膜透性,发芽率,根冠比,游离脯氨酸,丙二醛诸生理指标,对其耐盐性作出综合评判。研究结果表明,鲁梅克斯K-1杂交酸模对Na2SO4的耐盐性为0.8% ̄1.0%,对Na2CO3为0.2% ̄0.3%,高于此浓度表现为Na2SO4、Na2CO3盐胁迫的症状。  相似文献   

5.
王萍 《草业学报》1998,7(1):24-28
对Na2Co3胁迫下羊草生理和代谢变化的研究表明,在Na2Co3胁迫下,羊草幼苗叶片细胞膜相对透性增大,体内脯氨酸积累增加,无机Na含量增多,外源脱落酸(ABA)处理可促进羊草对K吸收,抑制Na^+吸收,减轻Na^+毒害,增强膜稳定性和渗透调节能力,并提高羊草生长代谢活性。  相似文献   

6.
星星草生长在0-600mmol/LNaCl和0-200mmol/LNa2CO3的盐胁迫下,测定了其生长状况及营养液中主要矿质离子的游离度、活度等。结果表明:相同Na^+活度下,Na2CO3对星星草的生长尤其是根生长的抑制作用明显大于NaCl。  相似文献   

7.
2.0%碳酸钠胁迫明显抑制星星草种子萌发,发芽率降低67.5%。萌发后幼根、芽 生长受抑。用10^-8,10^-5,10^-2ppm萘乙酸处理,使Na2CO3胁迫下的星星草种子发芽率分别提高22.2%、43.0%、51.2%和87.0%。萘乙处理对萌发后幼根、幼芽生长影响不明显。  相似文献   

8.
对盐渍化人工草地土壤盐分离子(Cl-、SO2-4、CO2-3、HCO-3、Na+、K+、Mg2+、Ca2+)及土壤有机质、全氮、全磷等营养成分在0~30cm土层内的动态变化规律进行了连续分析测定。为进一步客观评价“生物治碱”功效提供了可靠依据。  相似文献   

9.
盐类对丝素溶解效应的研究   总被引:1,自引:0,他引:1  
用0.5%Na2CO3溶液对茧层进行不同时间的脱胶试验,结果表明:0.5%Na2CO3溶液煮沸1h对茧丝脱胶效果较好,可达27.2%;将脱胶后的丝素烘干,用CaCI2、MgCI2、ZnCI2三种不同的氯化物控制在60℃、80℃和100℃不同的恒温下,每种药品均配成30%、40%、50%、60%四种不同浓度分别处理0.5h、1h、1.5h,经分析比较得知ZnCI2对丝素溶解性能最好,其次为CaCI2  相似文献   

10.
钾素营养对星星草幼苗抗碱性的影响   总被引:5,自引:1,他引:4  
通过不同水平钾素营养培养星星草幼苗,研究钾素营养对星星草幼苗抗碱性的影响。结果表明:在2.0%Na2CO3胁迫下,星星草幼苗钾素营养的最适浓度为1.35mmolL^-1KCl,此条件不仅对株高、干重和鲜重的增长有促进作用,而且受害程度最小,对Na2CO3胁迫的缓解作用最强,在一定程度上可提高星星草幼苗对Na2CO3胁迫的抗性。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

17.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

18.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

19.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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