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排序方式: 共有203条查询结果,搜索用时 15 毫秒
1.
目的对实验动物皮肤病原真菌2种培养方法进行了比较。方法将采集到的3只皮肤真菌感染病兔样品经由沙氏平皿法和沙氏试管斜面培养法分别进行培养。结果在3只真菌感染病兔中应用试管斜面法我们只检测到1例皮肤病原真菌阳性,而采用沙氏平皿法3例阳性全部检出。结论结合临床检测经验,我们认为本研究的沙氏平皿法优于沙氏试管斜面法,在实验动物皮肤病原真菌常规检测中具有推广应用价值。  相似文献   
2.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium.  相似文献   
3.
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX).  相似文献   
4.
蒙古高原岩黄芪属植物的分支分类学研究   总被引:6,自引:0,他引:6  
萨仁  赵一之 《植物研究》2001,21(1):18-23
以蒙古高原岩黄芪属植物为对象, 应用徐克学的最大同步法, 探讨了蒙古高原岩黄芪属(豆科)植物的系统演化, 并根据分支分类结果对蒙古高原岩黄芪属进行了系统学处理。作者首次将蒙古高原岩黄芪属分为岩黄芪亚属、半灌木岩黄芪亚属(新拟)和无刺岩黄芪组、丛枝岩黄芪组、无茎岩黄芪组、半灌木岩黄芪组等4 个组。本文对蒙古高原岩黄芪组的划分符合苏联植物志(1945)中的观点。  相似文献   
5.
Betchen  SA; Doty  RL 《Chemical senses》1998,23(4):453-457
Several fundamental questions remain enigmatic concerning human olfactorysensitivity, including (i) whether detection threshold differences existbetween the two sides of the nose (and, if so, whether such differences areinfluenced by handedness) and (ii) whether bilateral (i.e. binasal)stimulation leads to lower thresholds than unilateral stimulation (and, ifso, whether the degree of facilitation is inversely related to generalolfactory ability). In this study, and well-validated single staircaseprocedure was used to establish bilateral and unilateral detectionthresholds for the cranial nerve I stimulant phenyl ethyl alcohol in 130right- and 33 left-handed subjects. No differences in sensitivity betweenthe left and right sides of the nose were observed in either group.Bilateral thresholds were lower, on average, than unilateral thresholdswhen the latter were categorized in terms of left and right nares. However,the bilateral thresholds did not differ significantly from those of theside of the nose with the lower threshold. Overall smell ability, asmeasured by the University of Pennsylvania Smell Identification Test, didnot interact with any of the test measures. These data imply that (i) theleft and right sides of the nose do not systematically differ in detectionthreshold sensitivity for either dextrals or sinistrals and (ii) if centralintegration of left:right olfactory threshold sensitivity occurs, itseffects do not exceed the function of the better side of the nose.  相似文献   
6.
裂叶蒿(Artemisia tanacetifolia)、大籽蒿(Artemisia sieversiana)和艾(Artemisia argyi)是我国常见的蒿属(Artemisia)植物,其分布区域遍布全国.本文利用MaxEnt模型预测3种蒿属植物在当前气候条件以及未来两种气候情景下的潜在分布区.采用受试者工作特征...  相似文献   
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8.
The distribution of Na+ pump sites (Na+-K+-ATPase) in the secretory epithelium of the avian salt gland was demonstrated by freeze-dry autoradiographic analysis of [(3)H] ouabain binding sites. Kinetic studies indicated that near saturation of tissue binding sites occurred when slices of salt glands from salt-stressed ducks were exposed to 2.2 μM ouabain (containing 5 μCi/ml [(3)H]ouabain) for 90 min. Washing with label-free Ringer's solution for 90 min extracted only 10% of the inhibitor, an amount which corresponded to ouabain present in the tissue spaces labeled by [(14)C]insulin. Increasing the KCl concentration of the incubation medium reduced the rate of ouabain binding but not the maximal amount bound. In contrast to the low level of ouabain binding to salt glands of ducks maintained on a freshwater regimen, exposure to a salt water diet led to a more than threefold increase in binding within 9-11 days. This increase paralleled the similar increment in Na+-K+-ATPase activity described previously. [(3)H]ouabain binding sites were localized autoradiographically to the folded basolateral plasma membrane of the principal secretory cells. The luminal surfaces of these cells were unlabeled. Mitotically active peripheral cells were also unlabeled. The cell-specific pattern of [(3)H]ouabain binding to principal secretory cells and the membrane-specific localization of binding sites to the nonluminal surfaces of these cells were identical to the distribution of Na+-K+-ATPase as reflected by the cytochemical localization of ouabain-sensitive and K+-dependent nitrophenyl phosphatase activity. The relationship between the nonluminal localization of Na+-K+-ATPase and the possible role of the enzyme n NaCl secretion is considered in the light of physiological data on electrolyte transport in salt glands and other secretory epithelia.  相似文献   
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10.
Responses of cultured rat trigeminal ganglion neurons to bitter tastants   总被引:1,自引:2,他引:1  
Liu  L; Simon  SA 《Chemical senses》1998,23(2):125-130
The initial steps in taste and olfaction result from the activation by chemical stimuli of taste receptor cells (TRCs) and olfactory receptor neurons (ORNs). In parallel with these two pathways is the chemosensitive trigeminal pathway whose neurons terminate in the oral and nasal cavities and which are activated by many of the same chemical stimuli that activate TRCs and ORNs. In a recent single unit study we investigated the responses of rat chorda tympani and glossopharnygeal neurons to a variety of bitter-tasting alkaloids, including nicotine, yohimbine, quinine, strychnine and caffeine, as well as capsaicin, the pungent ingredient in hot pepper. Here we apply many of these same compounds to cultured rat trigeminal ganglion (TG) neurons and measure changes in intracellular calcium [Ca2+]i to determine whether TG neurons will respond to these same compounds. Of the 89 neurons tested, 34% responded to 1 mM nicotine, 7% to 1 mM caffeine, 5% to 1 mM denatonium benzoate, 22% to 1 mM quinine hydrochloride, 18% to 1 mM strychnine and 55% to 1 microM capsaicin. These data suggest that neurons from the TG respond to the same bitter-tasting chemical stimuli as do TRCs and are likely to contribute information sent to the higher CNS regarding the perception of bitter/irritating chemical stimuli.   相似文献   
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