共查询到20条相似文献，搜索用时 31 毫秒
1.
单克隆抗体在水产无脊椎动物血淋巴细胞研究中的应用 总被引：1，自引：0，他引：1
近年来,单克隆抗体在水产无脊椎动物血淋巴细胞研究中的应用越来越广泛,迄今报道的研究种类主要是对虾和贝类,另外还包括一些其他水产无脊椎动物,如海参等。主要应用于血淋巴细胞的识别和鉴定,并对其个体的发生和分化方面也进行了初步的研究。对单克隆抗体在水产无脊椎动物血淋巴细胞的分类、分布、发生和功能研究等方面的应用进行了综述。 相似文献
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犀角金线鲃的局部解剖 总被引：1，自引：1，他引：1
对犀角金线鲃残存眼球作了组织学切片观察,发现视网膜中只有视杆细胞,没有视锥细胞。另外对犀角金线鲃头上的角状突作了补充解剖,发现其内之骨为3块近似直角三角形的骨片组成,并非骨质管。 相似文献
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Villa P Bouville C Courtin J Helmer D Mahieu E Shipman P Belluomini G Branca M 《Science (New York, N.Y.)》1986,233(4762):431-437
Cannibalism is a provocative interpretation put forth repeatedly for practices at various prehistoric sites, yet it has been so poorly supported by objective evidence that later, more critical reviews almost invariably reject the proposal. The basic data essential to a rigorous assessment of a cannibalism hypothesis include precise contextual information, analysis of postcranial and cranial remains of humans and animals, and detailed bone modification studies. Such data are available from the Neolithic levels of the Fontbrégoua Cave (southeastern France) where several clusters of human and animal bones have been excavated. The analysis of these bones strongly suggests that humans were butchered, processed, and probably eaten in a manner that closely parallels the treatment of wild and domestic animals at Fontbrbégoua. 相似文献
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Frison GC 《Science (New York, N.Y.)》1976,194(4266):728-730
Stacked mammoth bones at the Colby site in northern Wyoming reflect human cultural activity that is believed to have been peripheral to the butchering and processing of the animals. A projectile point found beneath the first bones placed in the pile leaves no doubt of human involvement in the stacking of the bones, but the significance of this kind of cultural activity is open to several interpretations. 相似文献
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羊喉骨中硫酸软骨素提取工艺研究 总被引：1，自引：0，他引：1
以羊喉骨为原料,采用中性盐—弱碱方法提取硫酸软骨素,通过对浸提温度、盐解温度,乙醇沉淀浓度等因素对产品质量的影响研究,确定了羊喉骨中硫酸软骨素提取的适宜工艺条件,即浸提温度40℃,盐解温度90℃,乙醇沉淀浓度70%时,产品得率为7.6%,含量为84.9%,澄清度0.018,氮含量2.97%,产品合格。 相似文献
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针对高炉煤气供应系统用户端用气量急剧变化而影响高炉煤气管网运行安全的问题。依据某高炉煤气管网的实际运行工况,建立了模拟煤气管网系统发生事故状况下管内压力和流量变化的实验系统。整个实验模拟过程由实验台和数据采集系统完成,实验气源为空压机压缩储存的压缩空气,管网由一根主干管段和一个环管组成。在实验工况下,采用流量计、差压计对处于主管道及环管道上的关键点进行实时测量,通过数据采集系统得到管路系统上的关键量变化值,从而确定管道内气体的流量变化。研究结果表明：该实验系统产生的瞬时稳态流动可以很好地模拟因非管元件状态改变而产生的事故工况,对指导实际管道的安全运行有较大帮助。（图8,参10） 相似文献
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Analytical techniques more usually applied in mineralogy have revealed consistent structural differences between the bones of wild and domestic animals from archeological deposits. 相似文献
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利用精原干细胞建立转基因动物的研究进展 总被引：2，自引：0，他引：2
精原干细胞(spermatogonial stem cells,SSCs)是雄性哺乳动物体内的一种成体干细胞,在睾丸微环境中既具有自我更新潜能,又具有定向分化潜能,是自然状态下出生后,动物体内在整个生命期间进行自我更新并能将基因传递至子代的唯一成体干细胞。精原干细胞在建立转基因动物中具有重要的应用价值,现已成为转基因研究领域的热点之一。介绍了精原干细胞的来源、形成、类型及分化,同时对其在转基因动物研究中的应用做一综述。 相似文献
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Diving mosasaurs, plesiosaurs, and humans develop dysbaric osteonecrosis from end-artery nitrogen embolism ("the bends") in certain bones. Sixteen sperm whales from calves to large adults showed a size-related development of osteonecrosis in chevron and rib bone articulations, deltoid crests, and nasal bones. Occurrence in animals from the Pacific and Atlantic oceans over 111 years made a pathophysiological diagnosis of dysbarism most likely. Decompression avoidance therefore may constrain diving behavior. This suggests why some deep-diving mammals show periodic shallow-depth activity and why gas emboli are found in animals driven to surface precipitously by acoustic stressors such as mid-frequency sonar systems. 相似文献
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氟致小鼠肾脏组织形态结构损伤的观察 总被引：1，自引：0，他引：1
为研究氟致非骨相组织的损伤作用,选用20只20日龄的昆明小鼠,随机分为4组,每组5只,分别饲喂含0 mg/L、50 mg/L1、00 mg/L和150 mg/L氟化钠的饮水120 d,并通过石蜡组织切片观察氟对肾脏的损伤作用。研究结果表明:50 mg/L氟中毒组小鼠肾脏肾小管排列结构无异常变化,肾小球细胞出现空泡样病变。100 mg/L氟中毒组小鼠肾脏肾小管排列结构没有明显的异常,肾小球内皮细胞和肾小管上皮细胞出现空泡样变,并出现微核现象和凋亡样细胞,且近曲小管上皮细胞有脱落现象。150 mg/L氟中毒组小鼠肾脏肾小管排列结构轻微紊乱,肾小球内皮细胞和肾小管上皮细胞发生变性、坏死,肾小管内脱落的上皮细胞增多。 相似文献
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Biomechanics of mammalian terrestrial locomotion 总被引：9，自引：0，他引：9
A A Biewener 《Science (New York, N.Y.)》1990,250(4984):1097-1103
Mammalian skeletons experience peak locomotor stresses (force per area) that are 25 to 50% of their failure strength, indicating a safety factor of between two and four. The mechanism by which animals achieve a constant safety factor varies depending on the size of the animal. Over much of their size (0.1 to 300 kilograms), larger mammals maintain uniform skeletal stress primarily by having a more upright posture, which decreases mass-specific muscle force by increasing muscle mechanical advantage. At greater sizes, increased skeletal allometry and decreased locomotor performance likely maintain stresses constant. At smaller sizes, skeletal stiffness may be more critical than strength. The decrease in mass-specific muscle force in mammals weighing 0.1 to 300 kilogram indicates that peak muscle stresses are also constant and correlates with a decrease in mass-specific energy cost of locomotion. The consistent pattern of locomotor stresses developed in long bones at different speeds and gaits within a species may have important implications for how bones adaptively remodel to changes in stress. 相似文献
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唇鱼骨肌间小骨的骨化过程 总被引：2，自引：1，他引：1
利用整体骨骼染色的方法,对唇(Hemibarbuslabeo)早期发育阶段肌间小骨的形态发生进行观察,结果表明:在受精后35 d(dpf)之前,除了肌间小骨,唇所有其它骨骼均已骨化完成。肌间小骨在35 dpf(相应的体长为23.67 cm)开始在尾部区域骨化,髓弓小骨首先出现在尾部的第37～41肌节之间,脉弓小骨首先出现在尾部的39～40肌节之间,然后依次往前;到62 dpf(相应的体长为30.03cm)肌间小骨骨化全部完成。骨化过程中,唇肌间小骨是从简单的I型,到卜型,再到Y型,再分化为各种复杂形态。唇肌间小骨出现的时机和形态形成规律与其它鲤科鱼类相似,提示鲤科各亚科鱼类肌间小骨的骨化过程可能受同样的遗传机制控制。研究亮点:目前关于鲤科鱼类肌间小骨骨化模式的研究仅限于鲢亚科的鲢和模式动物斑马鱼,通过比较其它亚科鱼类肌间小骨的骨化模式,有助于探讨鲤科鱼类肌间小骨骨化模式的保守性。本文发现亚科唇的肌间小骨骨化模式与鲢非常相似,提示鲤科肌间小骨的骨化过程可能受同样的遗传机制控制。 相似文献
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An ossified Meckel's cartilage has been recovered from two early Cretaceous mammals from China. This element is similar to Meckel's cartilage in prenatal and some postnatal extant mammals and indicates the relationship of Meckel's cartilage with the middle ear in early mammals. The evidence shows that brain expansion may not be the initial factor that caused the separation of postdentary bones from the dentary as middle ear ossicles during mammalian evolution. The failure of the dentary to seize reduced postdentary elements during ontogeny of early mammals is postulated as an alternative mechanism for the separation. Modifications of both feeding and hearing apparatuses in early mammals may have led to the development of the definitive mammalian middle ear. 相似文献
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Scaling body support in mammals: limb posture and muscle mechanics 总被引：12，自引：0，他引：12
A A Biewener 《Science (New York, N.Y.)》1989,245(4913):45-48
The scaling of bone and muscle geometry in mammals suggests that peak stresses (ratio of force to cross-sectional area) acting in these two support elements increase with increasing body size. Observations of stresses acting in the limb bones of different sized mammals during strenuous activity, however, indicate that peak bone stress is independent of size (maintaining a safety factor of between 2 and 4). It appears that similar peak bone stresses and muscle stresses in large and small mammals are achieved primarily by a size-dependent change in locomotor limb posture: small animals run with crouched postures, whereas larger species run more upright. By adopting an upright posture, large animals align their limbs more closely with the ground reaction force, substantially reducing the forces that their muscles must exert (proportional to body mass) and hence, the forces that their bones must resist, to counteract joint moments. This change in limb posture to maintain locomotor stresses within safe limits, however, likely limits the maneuverability and accelerative capability of large animals. 相似文献
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粘菌是真核生物中一个特殊的重要类群，在系统演化，形态建成，发育分化等许多生物学方面具有重要的理论意义，但是，对于粘菌与其它生物间的系统关系以及粘菌内部的系统发育，一直存在着较大的争议，这正是许多生物学者从事粘菌培养，研究个体发育的原因，他们希望以此来获得可靠的系统发育证据。本文对粘菌的培养和个体发育研究进行了综述。 相似文献
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黄河鲤肌间骨发育的形态学观察 总被引：1，自引：1，他引：0
采用整体骨骼染色、形态学解剖的方法,对黄河鲤(Cyprinus carpio haematopterus)仔稚鱼肌间骨的形态发生及成鱼肌间骨数目、形态、分布进行研究。结果显示,黄河鲤14 dpf(day post fertilization,体长11.29mm)肌间骨首先在尾部出现,此时其他骨骼包括主轴骨及附肢骨均已骨化完全。伴随鱼体生长,肌间骨由尾向头依次骨化,26 dpf(体长15.60 mm)肌间骨骨化全部完成。黄河鲤肌间骨数在93~104之间,平均为98根;鱼体一侧髓弓小骨平均为34枚,脉弓小骨平均为15枚。黄河鲤肌间骨存在7种形态:"I"形、"卜"形、"Y"形、一端多叉形、两端两分叉形、两端多叉形和树枝形,越靠近鱼体前端肌间骨形态越复杂。研究结果为今后揭示黄河鲤肌间骨骨化的分子机制,培育少肌间骨甚至无肌间骨的黄河鲤提供了形态学基础。 相似文献
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目的观察大鼠膝关节前交叉韧带离断术后关节软骨形态学变化。方法 56只SD大鼠随机分为7组,每组8例,前交叉韧带离断术后当天及术后2、4、8、12、16、20周处死大鼠,用Pelletier评分及HE染色观察膝关节软骨损2伤情况。结果 Pelletier评分显示软骨损伤随造模时间延长而加重（χ=45.861,P〈0.05）,二者呈线性相关（F=178.836,P〈0.05）;髁上部软骨损伤比下部明显（P=0.000）,而内髁与外髁软骨损伤差异无统计学意义（P=0.736）。HE染色发现造模后软骨面裂隙形成、软骨细胞排列紊乱、潮线部分破坏。结论前交叉韧带离断后关节软骨损伤随时间推移而加重,其中髁上部软骨损伤程度较重。 相似文献