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1.
中国大鲵视网膜的光镜和扫描电镜研究   总被引:7,自引:0,他引:7  
用光镜和扫描电镜观察了大鲵视网膜各类细胞的形态及分布, 对视细胞和节细胞进行计数。视网腊中三个核层及两个网状层分布均匀,无中央凹。每张视网膜的视细胞总数约130000,节细胞约8000,视杆与视锥之比为8.5:1。扫描电镜下,视杆外节表面的小叶间沟清晰;视杆视锥外节均有从内节伸出的20-30条萼状突起;核周体表面亦有20-30条细胞质突起。文中还报道了幼体视细胞的形态及密度。讨论了上述结构的机能。  相似文献   
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Arthur P.Jacot(1923)报道过山东内陆的两栖动物,此后,王兴春等(1997)和陆宇燕等(1999)进行过报道.而山东省两栖动物的区系和地理区划尚无系统研究.本文在对山东省胶东半岛最大的山系--昆嵛山进行初步考察的基础上,仅就该地区的两栖动物组成和区系特征进行分析讨论,为研究山东省两栖爬行动物地理区划提供参考.  相似文献   
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蛇胸腺肌样细胞呈CRF和Mot免疫反应阳性陆宇燕李丕鹏(烟台师范学院生物系烟台264025)关键词蛇胸腺CRFMot胸腺微环境在T细胞发育分化过程中起着重要的作用,因此研究胸腺基质细胞的生物学特性已成为免疫生物学的又一热点。胸腺微环境结构复杂,基质...  相似文献   
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Paclobutrazol is a well-known plant growth regulator. However, the application of paclobutrazol in fragrant rice production has not been reported. The present study conducted a field experiment with two cropping seasons and three fragrant rice cultivars to investigate the effects of paclobutrazol application on yield formation, grain quality, 2-acetyl-1-pyrroline (2-AP, key component of fragrant rice aroma) biosynthesis, and photosynthesis of fragrant rice. At the initial heading stage, paclobutrazol solutions at 0 (control), 30, 60, 100, and 120 mg L?1 were foliar applied to fragrant rice plants, respectively. Compared with control, paclobutrazol treatments significantly (P?<?0.05) increased grain yield and seed-setting rate of fragrant rice cultivars by 6.77–22.82% and 5.09–25.66%, respectively. Increased contents of photosynthetic pigments (chlorophyll a, chlorophyll b, and carotenoid) and the improved net photosynthetic rate at the grain-filling stage were observed due to paclobutrazol treatments. The paclobutrazol application increased head rice rate and grain 2-AP content by 3.94–8.94% and 6.47–18.80%, respectively. Lower chalky rice rate and chalkiness were recorded in paclobutrazol treatment than in control. Moreover, foliar application of paclobutrazol increased proline and Δ1-pyrroline contents in fragrant rice by 7.90–32.12% and 13.21–34.90%. Overall, foliar application of paclobutrazol could enhance productivity, improve grain quality, and increase the 2-AP content of fragrant rice, and 100–120 mg L?1 was considered the suggested concentration of paclobutrazol application in fragrant rice production.

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采用石蜡切片与苏木精-伊红染色及扫描电镜,对雄性峨眉髭蟾Leptobrachium boringii的角质刺及其周边皮肤进行了显微结构和亚显微结构的观察。显微结构观察发现,峨眉髭蟾的角质刺属于皮肤衍生物,突起呈倒"V"形。角质刺由表皮和真皮构成,表皮为复层扁平上皮,可分成4层;最外层细胞角质化,细胞轮廓不清,被染成深红色。真皮由疏松结缔组织构成,分辨不出致密层与疏松层,其内未见皮肤腺,但有少量色素细胞与毛细血管分布。表皮嵴伸入到真皮层,在以往的无尾两栖类研究中未见报道。角质刺基部可见皮肤褶翻起将其包裹在内,皮肤褶向上延伸形成角质刺。扫描电镜观察表明,角质刺顶端呈锥形的"小山丘"状,表面可分辨出表皮细胞轮廓,细胞为呈覆瓦状排列的角质化细胞。角质刺与皮肤交界处为多边形的角质化细胞。角质化上皮细胞的上表面与下表面均具有凹凸不平的花纹结构,细胞之间以镶嵌的方式连接。  相似文献   
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Electroporation has been recently adapted for the transfer of macromolecules into cells of tissues in vivo. Although mature adipocytes constitute <20% of cells residing in adipose tissue, we hypothesized that fat cells might be susceptible to selective electrotransfer of plasmid DNA owing to their large size relative to other cells in the tissue. Results demonstrate the feasibility of electroporating DNA into mature fat cells with >99% selectivity over other cells in the tissue. Further experiments used the "adiporation" technique to image the subcellular targeting of fluorescent bioreporter molecules to the nucleus, mitochondria, and lipid droplets of adipocytes within intact adipose tissue. Finally, we utilized fluorescent bioreporters to examine the effects of constitutive activation of the beta-adrenergic signaling pathway in adipocytes. These results demonstrate that overexpression of rat beta1-adrenergic receptors alters the cellular morphology of white adipocytes in a fashion that mimics the effects of systemic infusion of beta3-adrenergic receptor agonists. Hallmarks of the altered morphology include pronounced fragmentation of the single lipid droplet, repositioning of the nucleus, and induction of mitochondrial biogenesis. These results indicate that activation of beta-adrenergic signaling within adipocytes is sufficient to induce a phenotype that resembles typical brown adipocytes and suggest that in vivo electroporation will allow molecular dissection of the mechanisms involved.  相似文献   
9.
2017年12月对南海永兴岛的爬行动物进行了短期调查,发现3种壁虎科Gekkonidae动物,分别是截趾虎Gehyra mutilata、原尾蜥虎Hemidactylus bowringii和疣尾蜥虎H.frenatus。其中,截趾虎和原尾蜥虎为中国南海岛屿的新记录。  相似文献   
10.
我国毒蛇的生物多样性   总被引:1,自引:0,他引:1  
陆宇燕  李丕鹏 《四川动物》2000,19(3):143-145
中国产蛇类9科65属约207种,其中有毒蛇63(或71)种,分隶4科28属,以管牙类蝰科为最多,计24种。其中陆栖毒蛇有10种亚种分化,以山烙铁头蛇为最多,达4个亚种。有海水型、淡水型、岛屿岩栖型、山地林区型、灌丛型、草原型和荒漠型等生态类型。中国毒蛇的物种、遗传和生态方面表现出复杂的多样性。  相似文献   
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