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Tomohiro SASANAMI Mei MATSUZAKI Shusei MIZUSHIMA Gen HIYAMA 《The Journal of reproduction and development》2013,59(4):334-338
The ability to store sperm in the female genital tract is frequently observed in
vertebrates as well as in invertebrates. Because of the presence of a system that
maintains the ejaculated sperm alive in the female reproductive tract in a variety of
animals, this strategy appears to be advantageous for animal reproduction. Although the
occurrence and physiological reasons for sperm storage have been reported extensively in
many species, the mechanism of sperm storage in the female reproductive tract has been
poorly understood until recently. In avian species, the specialized simple tubular
invaginations referred to as sperm storage tubules (SSTs) are found in the oviduct as a
sperm storage organ. In this review, we summarize the current understanding of the
mechanism of sperm uptake into the SSTs, maintenance within it, and controlled release of
the sperm from the SSTs. Since sperm storage in avian species occurs at high body
temperatures (i.e., 41 C), elucidation of the mechanism for sperm storage may lead to the
development of new strategies for sperm preservation at ambient temperatures, and these
could be used in a myriad of applications in the field of reproduction. 相似文献
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试验旨在探讨稳定可靠的贮精腺上皮细胞分离及原代培养方法,为研究鸡贮精机理提供细胞模型。以鸡输卵管的子宫阴道交接部组织样为材料,采用酶消化法和组织块培养法分离培养母鸡贮精腺上皮细胞,观察母鸡贮精腺上皮细胞的培养情况,比较不同细胞培养方法获得贮精腺上皮细胞的生长情况。结果表明,用胶原酶或胰酶单独消化母鸡子宫阴道交接部组织,经100目过滤后获得的贮精腺上皮细胞24 h后可贴壁,但48～72 h后细胞死亡;用胶原酶Ⅺ(0.01 g/mL)与胰酶(0.25%)先后消化母鸡子宫阴道交接部组织后再经100目过滤获得的贮精腺上皮细胞贴壁性良好,24～48 h细胞出现明显增殖,72 h后细胞增殖速度减慢,开始死亡;用组织块培养法7 d可获得鸡贮精腺上皮原代细胞,该细胞可传2～3代;用组织块培养法获得的细胞进行免疫组化试验,发现细胞表达贮精腺差异表达基因编码的NXPH1蛋白,该蛋白在培养细胞内的表达符合其分泌蛋白特性,表明组织块培养法所获细胞可用于后续研究。综上,用组织块培养法获得的鸡贮精腺上皮细胞可为研究母鸡贮精腺机制提供细胞模型。 相似文献
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应用光镜和电镜技术,系统观察雌性中华鳖输卵管精子储存情况,显示与精子储存有关组织结构与细胞形态。结果表明,精子储存在雌性中华鳖输卵管的蛋白分泌部后部至子宫部,但各段的组织结构及精子储存量存在一定差别。蛋白分泌部后部上皮较发达,由典型的高柱状纤毛细胞和分泌细胞构成,固有膜中腺体多为泡状腺。上皮和腺体中含有大量高密度的膜性分泌颗粒,此段只有少量的精子储存。峡部较窄且固有膜内无腺体,上皮排列紧密并呈迷路样迂回分布,上皮细胞内高电子密度分泌颗粒成团集中分布在核上方。峡部管腔中分布着大量的精子,靠近管腔的精子或精子头部嵌入上皮纤毛之间或顶端凹陷的胞质中,且精子嵌入部分的细胞结构保持完整。子宫前部形成垂直于管腔的储精小管(SST),子宫上皮及此段SST上皮的分泌颗粒电子密度不均,含高密度电子致密斑,腺体中的分泌颗粒也呈现不同的内部结构。子宫部及SST的管腔中储存有大量精子。这些区段复杂的细胞结构及分泌活动,可能在精子储存中发挥重要作用。 相似文献
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为了揭示模拟放牧对天山北坡草甸草原有机碳储量的影响,在2012-2013年采用刈割模拟放牧方式设置休牧、轻牧、中牧、重牧4个处理,研究了不同放牧强度下地上活体植物、凋落物、根系和土壤的有机碳储量的变化。研究表明,随着放牧强度的增大,地上植被生物量碳储量、凋落物碳储量和总碳储量均表现为休牧轻牧中牧重牧;根系碳储量呈轻牧休牧中牧重牧,与轻牧相比,中牧和重牧分别下降了42.25%和72.41%;土壤碳储量表现为休牧中牧轻牧重牧。随着土壤深度的增加,根系碳储量逐渐减小;土壤有机碳密度随土壤深度增加则呈现不同的变化,总体呈现下降趋势;根系和土壤碳储量表层化趋势显著,0-20cm土层约占总碳密度的40%。碳储量的含量表现为土壤根系地上生物量,土壤有机碳密度最多,占85%以上;凋落物碳储量最少。 相似文献
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Wardrop KJ Young J Wilson E 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):83-88
The effect of four different red blood cell storage media on in vitro parameters of stored canine red blood cells was studied. The storage media included citrate-phosphate-dextrose-adenine (CPDA-1), two additive solutions, and an additive solution modified by the addition of plasma. Biochemical and hematologic parameters, including red cell adenosine triphosphate (ATP); 2,3-diphosphoglycerate (2,3-DPG); pH; percent hemolysis; and supernatant sodium, potassium, and glucose were assessed immediately following preparation of the red cell concentrate and after 35 and 42 days of storage at 4 degrees C. All parameters changed significantly (p < 0.05) during storage. Significant differences due to effect of the storage media were also seen at each time period. After 35 days and 42 days of storage, CPDA-1 maintained the highest pH, potassium, and sodium values, and had the lowest 2,3-DPG, ATP (p=0.052), and glucose values. No differences were seen in hemolysis after 35 days of storage. No additional benefit was noted from the addition of plasma to the additive solution. The additive solutions compared favorably with CPDA-1. 相似文献
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为研究糠氨酸与蜂王浆新鲜度的关系,本文采用HPLC测定蜂王浆在不同储藏、加工条件下的糠氨酸含量,确定相互之间的变化规律。糠氨酸是蜂王浆在加工和储存过程中的蛋白质和糖类发生美拉德反应而生成的主要产物,它的含量随着存贮条件、加工条件、存放时间的不同而不同。研究蜂王浆中糠氨酸含量及其测定方法,用酸水解蜂王浆,固相萃取糠氨酸,反相离子对高效液相色谱紫外检测器检测,依据糠氨酸标准物质定量。发现随着存放时间和温度的变化,不同蜂新鲜度的蜂王浆中糠氨酸含量发生明显的变化。因此,糠氨酸含量可以作为评价蜂王浆新鲜度的一个重要指标。 相似文献
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为了研究种蛋储存期对孵化性能的影响,试验以散养东北当地土鸡种蛋为研究对象,研究不同保存期(1～3 d、4～7 d、8～15 d和16～30 d)种蛋孵化性能的变化。结果表明:东北当地散养土鸡种蛋的最佳保存时间为7 d,种蛋保存时间在1～3 d和4～7 d之间的受精蛋孵化率变化不明显,保存超过7 d的种蛋受精蛋孵化率显著降低(P<0.05),且保存时间越长受精蛋孵化率越低;随着保存时间的延长,胚胎死亡率增高,保存1～15 d对胚胎早期死亡率影响不大,保存时间超过15 d会导致中后期死胚率增高。说明保存时间对种蛋孵化性能起关键性作用。 相似文献
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为阐明草地盐碱化过程中草地植物群落结构及碳储量的变化,以辉河保护区内的天然草地、草地-盐碱地过渡带和盐碱地为研究对象,采用野外调查采样结合室内分析的方法进行测试研究。结果表明随着草地盐碱化加剧,植被群落结构组成趋于简单化;植被碳储量和生态系统碳储量均逐渐下降,表层土壤有机碳储量表现为过渡带>盐碱地>天然草地。植被碳储量的变化主要与地上植被类型、植被生长特性和土壤理化性质有关;表层土壤有机碳储量的变化主要是地上植被和土壤水分与不同盐碱化草地相互响应的结果,其中,pH会显著影响表层土壤有机碳储量(P<0.05);生态系统碳储量的变化受到植被更迭和土壤pH的影响。因此,温性草甸草原植被群落结构和碳储量均会受到草地盐碱化的影响。 相似文献
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Thoroughbred racehorses perform exercise at maximal intensities and typically display a hyperthermic exercise response, which can drive core body temperature to critical levels. Despite extremely efficient thermoregulatory mechanisms, certain weather conditions may affect the horse’s ability to cool and result in a syndrome referred to as exertional heat illness (EHI). This is characterised by central nervous system dysfunction, as well as cytotoxic effects of heat on cells, which can produce deleterious consequences. Early detection of exertional heat illness (EHI) in Thoroughbred racehorses can be difficult because signs are often vague and the measurement of rectal temperature as an indicator of hyperthermia is not practical. Best practice in the treatment of EHI in horses, as in human subjects, centres on early detection, rapid assessment and aggressive cooling. Research in human subjects has shown that EHI is manageable when recognised early and appropriate treatment provided. The aim of this study was to investigate the measurement of skin surface temperature (SST) by an infrared thermometer as an aid in the early detection of EHI. A skin surface temperature ≥39°C in the immediate postrace period is considered to be hot. It reflects the interaction of exercise-related metabolic heat production, physiological adjustments to the skin surface such as vasodilation and sweating, together with the effect of high ambient temperature. Most importantly, high SST is associated with a reduced core-to-skin temperature difference, which retards heat transfer from the deep body tissues to the skin and can hinder heat dissipation. Identification of horses with high SSTs can prioritise them for rapid cooling and curtail possible progression to EHI. 相似文献
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H M Müller 《DTW. Deutsche tier?rztliche Wochenschrift》1989,96(7):363-368
Procedures for lowering the production of mycotoxins in cereals before harvest are not available. Breeding of cereal varieties which are resistant to fusaria is a promising approach. Development of storage fungi and fusaria after harvest can be inhibited by drying with warm or ambient air, refrigerated storage, chemical preservation (e.g. by propionic acid, urea), and airtight storage. For the quantitative determination of fungal growth in feedstuffs a chemical indicator such as ergosterol must be determined. A preservation procedure can be regarded as effective only if it is able to inhibit mold growth completely. This is concluded from the observation that an initial toxin-free phase of growth which has been found in mold cultures with liquid medium could not be detected during refrigerated storage of wheat. Under these conditions the production of ochratoxin A and other mycotoxins by Penicillium strains started simultaneously with the production of ergosterol. For an effective ambient air drying of cereals the depth of the whole bulk and the velocity of air must afford complete drying within 8-10 days. During refrigerated storage of cereals maximal storage periods which depend on moisture content and temperature should not be exceeded. Maximal storage periods based on ergosterol determinations are described for wheat with an initial moisture content between 18 and 26% and storage temperatures of 4 and 10 degrees C. The effect of propionic acid concentration on the development of molds is described, recommendations for selecting optimal acid dosages are given.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Goicoa A Espino L Rodriguez I Puigdemont A Brazis P Rejas J 《Acta veterinaria Hungarica》2008,56(2):163-171
Sensitisation to mites is frequent in atopic dogs. The main mite genus involved in canine atopic dermatitis is Dermatophagoides. The importance of storage mite allergens in dogs has been controversial. The aim of this study was to evaluate the sensitisation rates against storage mites (Lepidoglyphus destructor and Tyrophagus putrescentiae) and house dust mites (Dermatophagoides farinae and D. pteronyssinus) in atopic dogs from Galicia, a highly humid and temperate region of Spain, using a FcepsilonRIalpha-based immunoglobulin E (IgE) in vitro test. The study was performed on 95 dogs suffering from atopic dermatitis and presenting detectable specific serum IgE levels: 91.6% of the dogs tested positive for storage mites, whereas sensitisation to house dust mites was detected in 87.4%. These results indicate the importance of storage mites in this specific geographic area. 相似文献
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为明晰不同放牧方式对祁连山高寒草甸有机碳、氮库的影响,本试验以祁连山东缘全年连续放牧（Continuous grazing,CG）、冷季重度放牧（Heavily grazing in cold season,HG）、冷季轻度放牧（Lightly grazing in cold season,LG）、划区轮牧（Rotational grazing,RG）和全年禁牧（Non-grazing,NG）的高寒草甸为研究对象,系统研究地上植物层、凋落物层、土壤层和根系层有机碳、氮库的变化。试验结果表明：HG,LG,RG和NG较CG均能显著（P<0.05）提高地上植物层、凋落物层、根系层和土壤层有机碳、氮储量,但土-草系统总有机碳、氮储量均在RG样地最高,其次是NG样地,再次是LG样地,在CG样地最低。RG较CG样地土-草系统有机碳储量提高了8 748 g C·m-2,氮储量提高了785 g N·m-2。可见,通过改变放牧方式能够有效提高高寒草甸土-草系统有机碳、氮储量,实现碳、氮增汇的目的。综合考虑草地土-草系统有机碳、氮储量及草地资源的有效利用,高寒草甸的最佳放牧方式为划区轮牧。 相似文献
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1. Sperm storage tubules in the ostrich start to develop at an early stage of oviductal growth. Concurrently, membrane-bound carbonic anhydrase was found in the cells of the storage tubules. 2. In mature ostriches the utero-vaginal junction averaged 11.5+/-2.1 cm in length and primary mucosal folds were extremely long and slender. Membrane-bound carbonic anhydrase was present in the cells of the sperm storage tubules. In the non-ciliated cells of the surface epithelium both membrane-bound and cytoplasmic activity was detected. 3. The possible role of carbonic anhydrase in the stimulation/inhibition of sperm motility by altering the pH was discussed. 相似文献
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[目的]对比自制酸奶与市售酸奶在贮藏期间的品质变化。[方法]通过乳酸菌活菌数、酸度、pH值等指标,先探究自制酸奶在发酵过程中的品质变化,后与市售酸奶进行对比研究。[结果]自制酸奶过程中,发酵开始3 h后,随着乳酸菌发酵产物乳酸的累积,酸度上升、pH值下降,乳酸菌活菌数大幅度上升。发酵开始7 h后,乳酸菌总数开始下降,酸度的增加趋势和pH的降低趋势都有所减缓。在贮藏阶段,随着贮藏时间的增长,各种酸奶品质变化基本相同,乳酸菌含量先升后降,pH值下降,酸度上升。在4℃贮藏条件下,品质变化小于25℃。[结论]冷藏处理下酸奶的品质下降更慢,在自制或者购买酸奶时应该尽可能选择冷藏处理,开盖后尽快饮用完。两种酸奶具有不同的特点,消费者可以根据需求进行选择。总之,本研究为酸奶的安全贮藏提供参考依据。 相似文献
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乙烯是参与果实成熟、软化和衰老的重要激素,果实成熟时的乙烯释放量水平是决定果实货架期的关键因素。本研究以涵盖不同成熟期的28个砂梨品种为对象,通过测定其果实成熟采后常温贮藏过程中的乙烯释放量和硬度变化,判断其呼吸跃变类型。结果显示,多数早熟砂梨品种成熟后乙烯释放量较高,并且迅速上升于采后常温贮藏10~15d抵达峰值,表现为呼吸跃变型果实;而多数中晚熟乙烯释放量较低且采后乙烯释放量增加极为缓慢,显示为非呼吸跃变型特征。发掘出特异种质两份,即早熟非呼吸跃变型品种‘鄂梨2号’和晚熟呼吸跃变型品种‘金水1号’。本研究鉴定结果可为这些砂梨品种的生产和育种利用提供依据。 相似文献