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11.
The influence of trehalose on European mouflon spermatozoa cryopreservation during the non-breeding season was tested. Semen was frozen in two different extenders: (a) recommended Tris-based ram extender (CTR); (b) CTR extender supplemented with trehalose 0.147 mm (TRH). Sperm viability and acrosome integrity were assessed using propidium iodide and fluorescein isothiocynate labelled Pisum Sativum agglutinin. Trehalose significantly enhanced sperm viability after thawing compared with CTR extender (62.7% vs 51.8%; p < 0.05), whereas no differences were observed on acrosome integrity (42.9% vs 42.1%). Trehalose influence was also evidenced in the in vitro fertility test performed with sheep oocytes matured in vitro. Both fertilization rates (60.9% TRH vs 43.6% CTR; p < 0.05) and cleavage rates (58% TRH vs 39.8% CTR; p < 0.001) were higher for trehalose frozen semen compared with control extender frozen semen. A higher percentage of zygotes resulting from fertilization with trehalose cryopreserved semen presented the first cleavage earlier if compared with the group fertilized with control semen (48.7% vs 31.5%, respectively; p < 0.01). This result was confirmed by embryo kinetic development. Fertilization with trehalose cryopreserved semen leaded to an higher percentage of blastocysts (40.2% vs 27.8% CTR; p < 0.05), and enhanced in particular the number of blastocysts that developed on the day 6th of culture (28.6% vs 17% CTR; p < 0.05). Our data demonstrated that, during mouflon non-breeding season, trehalose extender enhances spermatozoa viability and its in vitro fertilizing capacity, allowing the production of an higher number of blastocysts.  相似文献   
12.
Mouse 3T3 cell lines capable of constitutively synthesizing an RNA complementary to the messenger RNA encoding TIMP, tissue inhibitor of metalloproteinases, were constructed by transfection with appropriate plasmid constructs. Many of the lines were down-modulated for TIMP messenger RNA levels and secreted less TIMP into the culture medium. In comparison to noninvasive, nontumorigenic controls, these cells not only were invasive in a human amnion invasion assay, but also were tumorigenic and metastatic in athymic mice. These results indicate that TIMP suppresses oncogenicity, at least in immortal murine 3T3 cells.  相似文献   
13.
氮磷缺乏对薏苡生长及其生理特性的影响   总被引:1,自引:0,他引:1  
以贵州省黔西南州兴仁县薏苡为试材,采用沙培盆栽方式设置对照(全素营养)、缺氮、缺磷、缺氮磷4个处理,测定分析了薏苡生长前期各形态指标、叶绿素含量、抗氧化酶系统及可溶性糖的含量,探讨氮磷元素缺乏对薏苡生长及生理特性的影响,以期提高薏苡的产量及品质。结果表明:1)缺氮、缺磷、缺氮磷均显著降低薏苡株高、根长、总叶片数、比叶面积及叶绿素含量,导致总生物量较对照分别降低80.65%、77.88%、91.24%;2)缺氮、缺磷、缺氮磷显著增加丙二醛(MDA)含量及过氧化氢酶(CAT)活性,缺氮时过氧化物酶(POD)活性降低14.29%,缺磷、缺氮磷时活性升高;3)薏苡可溶性糖含量在缺磷时较对照显著增加102.00%,缺氮和缺氮磷时可溶性糖含量分别较对照显著降低54.35%、34.59%。缺素处理总体上抑制了薏苡的生长,且缺氮磷比单独缺氮、缺磷对薏苡生长及生理的抑制作用更明显。  相似文献   
14.
This study was carried out to investigate the effect of dietary supplementation with molecular or nano‐clay binders on biochemical and histopathological examination of organs of turkeys fed diets contaminated with aflatoxin B1. Two hundred and sixteen unsexed 1‐day‐old British United Turkeys were randomly allotted to nine diets in a 3 × 3 factorial arrangement of diets supplemented with no toxin binder, molecular toxin binder (MTB) and nano‐clay toxin binder, each contaminated with 0, 60 and 110 ppb aflatoxin B1 respectively. There were three replicates per treatment with eight turkeys per replicate. Biochemical analyses, organ weights and histopathological changes of some organs were examined at the end of the study which lasted for 84 days. Turkeys fed diets supplemented with molecular and nano‐binders showed higher (p < 0.001) total serum protein, reduced (p < 0.001) serum uric acid and GGT concentration values when compared with those fed aflatoxin‐contaminated diets supplemented with no binder. Turkeys fed aflatoxin‐contaminated diets supplemented with no binder had increased (p < 0.001) AST and ALT concentration when compared with other treatments. The heaviest (p < 0.001) liver and intestinal weight was noticed with turkeys fed diets supplemented with no binder and contaminated with 110 ppb aflatoxin B1. Pathologically, there was no visible morphological alteration noticed in all turkeys fed uncontaminated diets and nano‐clay‐supplemented group. Hepatic paleness, hepatomegaly and yellowish discolouration of the liver were observed with turkeys fed diets containing no binder but contaminated with 60 and 110 ppb aflatoxin B1. Intestinal histopathological changes such as goblet cell hyperplasia, villous atrophy and diffuse lymphocytic enteritis were more prominent in turkeys fed diets containing no toxin binder and MTB. In conclusion, there were improved biochemical parameters and reduced deleterious effects of aflatoxin B1 in turkeys fed diet supplemented with clay binders. However, the improvement was more conspicuous in the nano‐clay‐supplemented group than molecular clay group.  相似文献   
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16.
以适于一次性采收的辣椒新品种DU01为试验材料,设置5个种植密度,对DU01的光合特性及产量构成因素等进行研究.结果表明,盛果期后,DU01的叶面积、气孔导度(Gs)、胞间CO2浓度(Ci)和蒸腾速率(Tr)随着密度的增加而降低,叶绿素a(Chla)、叶绿素b(Chlb)、类胡萝卜(Car)和总叶绿素(Chlt)含量随...  相似文献   
17.
The effect of dietary inclusion of fermented pigeon pea meal (FPPM) on growth response, apparent nutrient digestibility, haematological indices and serum biochemistry of cockerel chicks was studied using 240-day-old cockerel chicks allotted to four dietary treatments consisting of 60 birds each. Four experimental diets were formulated to include FPPM at 0, 50, 100 and 150?g/kg inclusion levels, respectively. Each of the diets was fed to 60 birds replicated six times with ten birds per replicate. The feeding trial lasted for 56?days. Results indicated that final live weight (linear (L). quadratic (Q): P??0.05) by the inclusion of FPPM. Haemoglobin and serum uric acid concentrations were also reduced (P?相似文献   
18.
为确定丛枝菌根(arbuscular mycorrhizal,AM)真菌对石漠化地区植物及土壤养分化学计量特征的影响,本研究以石漠化地区经济树种桑树为研究对象,通过模拟石漠化地区季节性干旱,研究水分供应发生变化时,AM真菌对桑树幼苗和土壤中养分调控作用。为模拟石漠化地区季节性干旱,试验设置正常供水和自然干旱2个时期,每个时期均设未接种对照(-M)、接种摩西斗管囊霉(Fm)和接种根内根孢囊霉(Ri)3个处理。桑树收获后,测定植物、土壤中的C、N、P、K含量。结果表明:在正常供水、自然干旱2个时期,接菌处理对桑树幼苗的促生效果显著,干旱胁迫发生之后,Ri菌种与桑树的亲和性、促生效果均强于Fm菌种。接菌处理对桑树幼苗N、P营养改善作用尤为明显,无论水分供应条件如何,接菌处理都显著增加桑苗各部分N、P含量。对比土壤养分含量发现,接菌处理增加了土壤有效P含量,降低了土壤中C含量,正常供水条件下,接种Fm、Ri分别使得土壤C含量下降了7.00%和8.55%。对比土壤养分计量比发现,正常供水条件下,接菌处理显著提高了土壤中的碳磷比(C/P)和氮磷比(N/P);干旱胁迫条件下,接菌处理显著增加氮磷比(N/P)。综上所述,石漠地区发生季节性干旱时,AM真菌可以影响桑树对C、N、P养分吸收和分配,依据水分供应的变化和对养分资源需求的不同,调控土壤、植物体中C、N、P配比。  相似文献   
19.
Among the factors that affect in vitro embryo development, oxygen atmosphere is considered to be of great influence. In this study, we evaluated the influence of two different oxygen atmospheres during in vitro fertilization (IVF) of ovine oocytes on their developmental capacity and quality assessed by cryotolerance. Cumulus oocyte complexes derived from ovaries of slaughtered sheep were matured in vitro and subsequently fertilized under low (5%) or high (20%) oxygen atmospheres, and cultured in SOF + aa + 0.4% BSA in 5% CO2 and 5% O2 up to blastocyst stage. The cleavage rates obtained in the fertilization system at 20% O2 were significantly higher than those obtained in the 5% O2 fertilization system (61.2% vs 50.8%; p < 0.01). The distribution of cleaved oocytes at 22, 26 and 40 h of culture intervals was not different in the low or high O2 atmosphere (31.4%, 26.4% and 42.1% vs 28.0%, 29.3% and 42.7% respectively). Blastocysts output on the 6th day post-fertilization (dpf) was significantly higher when oocytes were fertilized under 5% O2 concentration (63.04% in 5% O2 vs 47.36% in 20% O2), while on the 7th dpf the higher number of blastocysts was obtained in the 20% O2 system (35.10%.in 20% O2 vs 26.09% in 5% O2). After vitrification no differences were observed between low or high oxygen atmosphere in the viability rates of blastocysts obtained on day 6 (93.6% vs 96.5%), on day 7 (46.3% vs 41.7%) and on day 8 (11.1% vs 6.6%). After differential staining, no significant differences were observed in the total cell number and inner cell mass and trophoblastic cells ratio of blastocysts produced on 6 dpf (189.6 +/- 51.3 and 0.260 +/- 0.07 vs 223.3 +/- 45.6 and 0.277 +/- 0.09), on 7 dpf (168.3 +/- 25.1 and 0.316 +/- 0.06 vs 172.1 +/- 33,6 and 0.320 +/- 0.06) and on 8 dpf (121.2 +/- 23,8 and 0.302 +/- 0.03 vs 117.0 +/- 35.1 and 0.313 +/- 0.04) under low or high oxygen atmosphere respectively). In conclusion, our data suggest that low oxygen atmosphere during IVF affects positively the production of high quality ovine blastocysts.  相似文献   
20.
通过研究不同浓度NaCl溶液对赤小豆和红豆种子萌发及幼苗生长的影响,探讨赤小豆和红豆的耐盐能力。结果表明:随着NaCl浓度升高,赤小豆和红豆的发芽率、发芽势、发芽指数、活力指数、耐盐指数均显著降低,等浓度NaCl处理下,红豆的发芽率、发芽势、发芽指数、活力指数、耐盐指数均较赤小豆高,且萌发抑制率相对较低。赤小豆与红豆幼苗根长、芽长和鲜重均显著降低,等浓度NaCl处理下,红豆幼苗的根长、芽长和鲜重指标均较赤小豆高。研究表明红豆比赤小豆耐盐性更强,更能在盐胁迫环境下生长。  相似文献   
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