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1.
为研究油茶(Camellia oleifera A)嫁接时穗条和砧木创伤后内源激素动态变化规律,解析影响砧穗嫁接面愈合的生理机制,为油茶砧穗愈合生长机理提供理论支持。以树龄6年的长林18号和53号的穗条和实生砧木为材料,按照芽苗砧嫁接方法切割穗条S0(0 min)、S10(10 min)、S40(40 min)和砧木茎段Z0(0 min)、Z10(10 min)后,利用液质联用法(HPLC-MS)测定吲哚乙酸(IAA)、脱落酸(ABA)、反式玉米素(TZR)、玉米素(Zeatin)、水杨酸(SA)和茉莉酸(JA)含量,分析不同时间段内源激素变化及品种间差异的关系。结果显示:创伤后18号的TZR、Zeatin和SA含量总体高于53号;18号IAA、SA和JA逐渐下降;TZR和Zeatin分别在S10和S0达最高值后下降;ABA在S10达最高值。53号IAA和JA爱S10达最高值后下降;TZR、Zeatin和SA在S10达低值后逐渐上升;ABA在S0达高值后逐渐下降。砧木茎段创伤前后激素含量除JA外18号高于53号;两品种Z0时激素含量下降,Z10后上升,仅53号ABA和SA含量在Z0达高值后下降。砧木茎段和根部激素含量在品种间除JA外18号高于53号,茎段的IAA、ABA高于根部,其他激素为根部高于茎段。激素比值在品种间和部位间差异明显;IAA/ABA、IAA/TZR、IAA/Zeatin和IAA/JA、ABA/TZR、ABA/Zeatin和ABA/JA比值为53号高于18号;穗条内SA/IAA为18号高于53号,SA/JA和SA/ABA为53号高于18号;砧木茎段均为18号高于53号;TZR/SA、TZR/JA比值在穗条和砧木茎段为18号高于53号。两品种创伤后IAA与JA极显著正相关,而IAA与SA,SA与JA在18号极显著正相关,53号极显著或显著负相关;53号TZR、Zeatin、SA间极显著或显著正相关,JA与TZR、Zeatin和SA极显著负相关。砧木茎段创伤后18号激素间为极显著或显著正相关;53号TZR和Zeatin与IAA、JA极显著正相关,与SA存在显著负相关,SA与JA有显著负相关。砧木茎段和根部间品种间仅在SA与各激素间相关性存在差异,其他激素间存在极显著正相关或负相关。综上所述,砧穗创伤后激素水平上18号在创伤面易于愈伤组织发育,而53号抗逆激素水平较高且与细胞分裂增殖类激素负相关,可能影响53号嫁接后愈合生长;嫁接应在创伤后10 min内较为适宜;砧穗间激素含量及比值的差异可能会影响后期嫁接部位形态重建以及穗条生长。  相似文献   

2.
P Ernfors  C Wetmore  L Olson  H Persson 《Neuron》1990,5(4):511-526
Cells expressing mRNA for hippocampus-derived neurotrophic factor (HDNF/NT-3) or brain-derived neurotrophic factor (BDNF) were identified by in situ hybridization. In the rat brain, HDNF mRNA was predominantly found in pyramidal neurons in CA1 and CA2 of the hippocampus. Lower levels of HDNF mRNA were found in granular neurons of the dentate gyrus and in neurons of the taenia tecta and induseum griseum. BDNF mRNA-expressing cells were more widely distributed in the rat brain, with high levels in neurons of CA2, CA3, and the hilar region of the dentate gyrus, in the external and internal pyramidal layers of the cerebral cortex, in the claustrum, and in one brainstem structure. Lower levels were seen in CA1 and in the granular layer of the hippocampus, in the taenia tecta, and in the mammillary complex. In peripheral tissues, HDNF mRNA was found in glomerular cells in the kidney, secretory cells in the male rat submandibular gland, and epithelial cells in secondary and tertiary follicles in the ovary. Cells expressing BDNF mRNA were found in the dorsal root ganglia, where neurons of various sizes were labeled.  相似文献   

3.
Skakun VN  Aseev MV  Shawi A  Baranov VS 《Genetika》1999,35(9):1280-1288
The allele polymorphism of the AGC short tandem repeat (STR) of exon 1 of the androgen receptor (AR) gene located in Xq11-12, ATCT STR of intron 40 of the von Willebrand factor (vWF) gene located in chromosome 12p12, and AGAT STR of an anonymous DNA sequence (STRX1) from the short arm of the X chromosome was analyzed in the Georgian, Uzbek, and Russian populations. Polymerase chain reaction (PCR) with DNA of unrelated persons revealed 14 AR, 7 vWF, and 7 STRX1 alleles in Georgians; 14, 8, and 6 alleles, respectively, in Uzbeks; and 16, 8, and 9 alleles, respectively, in Russians. The heterozygosity at these STR was 0.61, 0.78, and 0.46 in Georgians; 0.60, 0.83, and 0.44 in Uzbeks; and 0.80, 0.70, and 0.58 in Russians. The correspondence of genotype frequencies to the Hardy-Weinberg equilibrium was observed with AR STR in Russians and Uzbeks, STRX1 STR in Georgians, and vWF in all three populations. A significant deviation from the equilibrium was found for STRX1 in Russians and Uzbeks and AR in Georgians. The potential of individualization was 0.05 for AR, 0.13 for vWF, and 0.18 for STRX1 in Georgians; 0.04, 0.09, and 0.13, respectively in Uzbeks; and 0.05, 0.14, and 0.07, respectively, in Russians. The allele and genotype frequency distributions of each STR were analyzed in all three populations. Allele frequencies in the populations were compared by the Kolmogorov-Smirnov test. The Russian population significantly differed in allele frequencies of the three STR from Uzbeks and in those of STRX1 and AR from Georgians. Georgians and Uzbeks significantly differed in vWF and STRX1 frequencies. The possibility of using the three STR in molecular diagnosis of the corresponding monogenic diseases, population genetic studies, and personal identification is discussed.  相似文献   

4.
Densities of pressure, pain and temperature spots in the back of the hand in 551 students and two-point discrimination thresholds in the hand, the face and the mouth in 684 students were measured. The mean numbers of pressure, pain, warm and cold spots in the back of the hand were 24.7/cm2, 130.5/cm2, 3.4/cm2 and 9.1/cm2, respectively. The mean thresholds of two-point discrimination were 1.7 mm in the tip of the tongue, 2.4 mm in the upper lip, 5.5 mm in the lower jaw, 7.5 mm in the palm, 8.8 mm in the forehead, and 11.8 mm in the back of the hand. There were mostly no differences between males and females in the values of sensory spots and two-point discrimination thresholds.  相似文献   

5.
The present paper describes the effect of exogenous oestradiol and progesterone on the AChE activity in nerves of the ovary, oviduct, uterus, and vagina, and on morphological features of the AChE-positive nerves of these organs in sexually immature pigs. Studies were carried out on 30 sexually immature pigs, 37 to 43 kg in weight, at the age of 115 to 125 d, of the BWP (Big White Polish) race. The animals were divided into 4 groups. Group I (n = 6) constituted the control. Animals in group II (n = 8) received oestradiolum benzoicum. Those in group III (n = 8) were given progesterone, and in group IV (n = 8) oestradiol and progesterone. Oestradiol injections resulted in a 1.2-fold increase of AChE activity in the ovary, 1.3-fold in the oviduct, 1.7-fold in the uterine horn, and a 1.2-fold decrease of this activity in the cervix, while no differences were noted in the vagina. Progesterone injections did not affect AChE activity in the ovary, while a 1.1-fold increase was observed in the oviduct, 1.2-fold in the uterine horn and 1.1-fold in the cervix compared to the control. A 1.1-fold decrease of this activity was observed in the vagina. Joint injections of oestradiol and progesterone resulted in about a 1.4-fold increase of AChE activity in the ovary, 1.3-fold in the oviduct, 1.4-fold in the uterine horn, 1.6-fold in the vagina, while no changes were observed in the cervix. The results suggest the effect of the administered hormones upon AChE activity in the organs under study, mainly in the oviduct, uterine horn, and vagina. They also point to the possibility of a synergic effect of oestradiol and progesterone as regards to an increase of the activity.  相似文献   

6.
黄土丘陵区不同植被根际土壤微量元素含量特征   总被引:4,自引:0,他引:4  
为了解黄土高原不同植被土壤微量元素的根际效应,分析了该地区柠条、沙棘、沙打旺、柳枝稷、阿尔泰狗娃花和茵陈蒿6种植被根际与非根际土壤中有机碳、全氮、Mn、Cu、Fe、Zn含量.结果表明: 6种植被中,柠条、阿尔泰狗娃花和茵陈蒿根际土壤的有机碳、全氮含量高于非根际土壤;除柠条和沙棘外,其余4种植被非根际土壤pH值均显著高于根际土壤.6种植被根际土壤有效Mn含量均低于非根际;柠条、沙打旺和柳枝稷根际有效Cu含量显著高于非根际,表现出强烈根际富集现象.除沙打旺外,其他5种植被根际有效Fe含量均略高于非根际.沙打旺、柳枝稷、茵陈蒿和阿尔泰狗娃花表现出强烈的有效Zn根际富集现象.根际与非根际土壤有机碳、全氮与有效Mn、有效Zn,以及有效Mn与有效Zn呈极显著正相关.根际土壤pH值与有效Mn和有效Zn呈显著负相关.由于不同植物根系的生长特征、根际pH值及微生物种类等的差异,不同植被根际的微量元素含量不同,茵陈蒿根际4种微量元素含量高于其他植被.  相似文献   

7.
湖北后河国家级自然保护区位于湖北、湖南交界处的五峰县境内,属武陵山东段余脉山地,为我国地势的第二阶梯向第三阶梯的过渡地带,是我国三大物种特有中心之一的川东-鄂西特有中心和第三纪古植物的孑遗中心的重要组成成分之一。该区拥有丰富的生物多样性,尤以第三纪孑遗珍稀濒危植物集中分布群落为典型特征。该区地貌复杂,海拔落差大,微生境复杂多变,拥有从低山河谷常绿阔叶林到亚高山灌丛或草甸等多种生态系统和多种植被类型。目前已知该区有陆生脊椎动物25目74科306种,占湖北省总种数的63.5%和全国总种数的13.0%,其中有51种国家重点保护野生动物和70种湖北省级重点保护动物;已知该区维管植物有194科819属2088种,占湖北省总种数的34.4%和全国总数的7.5%,属国家特有、珍稀濒危或重点保护的植物约有70余种;已知藓类植物33科90属192种和叶附生苔类植物3科7属7种,分别占全国总种数的9.8%和4.2%。该区不仅拥有丰富的动植物区系成分多样性,而且具有高度的群落物种多样性和经济类型多样性。尽管该区的生物多样性研究得到长足发展,但主要集中在物种种类的调查与区系成分研究和少数群落格局物种多样性研究,而遗传多样性方面的研究十分欠缺。物种多样性研究也不平衡,昆虫类和苔藓植物的调查刚起步,真菌资源、淡水鱼类等尚未开展研究。  相似文献   

8.
By Falck's method monoaminocytes of the arteries in the encephalon base were studied in Teleostei (Anarhichas lupus, Eleginus navaga, Leuciscus brandti Liza soiuy in amphibians (Rana temporaria, Rana semiplicata, Bufo bufo), in reptiles (Testudo horsfiedli, Trionyx chinensis) and in birds (blue rock pigeon, hen). Specific and individual peculiarities in chromaffinocyte, labrocyte and melanophore distribution were revealed in the vertebrate cranial arteries. In all the animals studied chromaffin cells are more frequent in the lateral olfactory artery. Their concentration decreases towards cranial, caudal branches of the internal carotid artery, the main and internal carotid arteries. The greatest amount of chromaffinocytes was found in the cranial arteries of Anarhichas lupus, then comes Eleginus navaga, Leuciscus brandti and Liza soiny Concentration of melanophores in fishes increases with enlargement of the vascular diameter; these cells are more abundant in the arteries of Anarhichas lupus and in less amount in Eleginus navaga, Leuciscus brandti and Liza. Pigmented cells are more abundant in the internal carotid artery and its cranial and caudal branches than in lateral, olfactory and main arteries of fishes. On the contrary, in amphibians, the main artery contains a maximal concentration of melanophores. In the tortoise cranial arteries, there are only single cells of this type, and birds have no such cells. Labrocytes occur in the greatest concentration in the tortoise cranial arteries and in other vertebrates they are scarce or absent. As a whole, the role of the local endocrine link in regulation of the brain arteries mobility decreases in the following way: fishes--amphibians--reptiles--birds.  相似文献   

9.
To elucidate whether the extent of element accumulation in the arteries and cardiac valves with aging was different between different races, the authors investigated the accumulation of elements in the arteries and cardiac valves of the Thai with aging and the relationships among elements in the cardiac valves. After ordinary dissection at Chiang Mai University was finished, 16 arteries and 4 cardiac valves were resected and element contents were determined by inductively coupled plasma-atomic emission spectrometry. In the 16 arteries, the average content of calcium was the highest in the site of the abdominal aorta ramifying into the common iliac arteries, and it decreased in the order internal iliac, coronary, abdominal aorta, common iliac, external iliac, superior mesenteric, inferior mesenteric, thoracic aorta, brachial, radial, common carotid, subclavian, ulnar, axillary, renal, and internal thoracic arteries. The average contents of phosphorus and magnesium in respective arteries were parallel with the average contents of calcium, except for the coronary artery. In comparison with the arteries of the Japanese, the trend of calcium accumulation in the arteries of the Thai was almost similar to that in the arteries of the Japanese, except for the coronary artery and thoracic aorta. The calcium accumulation in the coronary artery was much higher in the Thai than in the Japanese, whereas that in the thoracic aorta was lower in the Thai than in the Japanese. Regarding elements in the cardiac valves, the calcium content increased remarkably in the seventies in the aortic valve and in the nineties in the pulmonary valve, but it hardly increased in both the mitral and tricuspid valves with aging. The average content of calcium was the highest in the aortic valve, and it decreased in the order pulmonary, tricuspid, and mitral valves. Regarding the relationship among elements in the aortic valves, it was found that there were extremely significant direct correlations among the contents of calcium, phosphorus, and magnesium, whereas there were significant direct correlations between zinc and either calcium or phosphorus contents. Although significant correlations were found between sulfur and the other element contents in the aortic valves of the Japanese, no significant correlations were found between them in the aortic valves of the Thai. In the mitral valves, extremely or very significant direct correlations were found among the contents of calcium, phosphorus, magnesium, and sulfur, with some exceptions that there were no significant correlations between phosphorus and either magnesium or sulfur contents. In addition, no significant correlation was found in the calcium content between the aortic valve and coronary artery in the same individuals.  相似文献   

10.
Yang XG  Li Y  Dai SW  Liu ZJ  Wang WF 《应用生态学报》2011,22(12):3177-3188
Based on the 1961-2007 ground surface meteorological data from 558 meteorological stations in China, this paper analyzed the differences of agricultural climate resources in China different regions, and compared the change characteristics of the agricultural climate resources in 1961-1980 (period I) and 1981-2007 (period II), taking the year 1981 as the time node. As compared with period I, the mean annual temperature in China in period II increased by 0.6 degrees C, and the > or = 0 degrees C active accumulated temperature in the growth periods of chimonophilous crops and the > or = 10 degrees C active accumulated temperature in the growth periods of thermophilic crops increased averagely by 123.3 degrees C x d and 125.9 degrees C x d, respectively. In 1961-2007, the mean annual temperature increased most in Northeast China, and the > or = 10 degrees C active accumulated temperature in the growth periods of thermophilic crops increased most in South China. The whole year sunshine hours and the sunshine hours in the growth periods of chimonophilous crops and of thermophilic crops in period II decreased by 125.7 h, 32.2 h, and 53.6 h, respectively, compared with those in period I. In 1961-2007, the annual sunshine hours decreased most in the middle and lower reaches of Yangtze River, while the sunshine hours in the growth periods of chimonophilous crops and of thermophilic crops decreased most in North China and South China, respectively. In the whole year and in the growth periods of chimonophilous and thermophilic crops, both the precipitation and the reference crop evapotranspiration in this country all showed a decreasing trend, with the largest decrement in the precipitation in the whole year and in the growth periods of chimonophilous and thermophilic crops in North China, the largest decrement in the reference crop evapotranspiration in the whole year and in the growth periods of thermophilic crops in the middle and lower reaches of Yangtze River, and the largest decrement in the reference crop evapotranspiration in the growth periods of chimonophilous crops in Northwest China. In 1961-2007, the climate in China in the whole year and in the growth periods of thermophilic crops showed an overall tendency of warm and dry, and the climate in the growth periods of thermophilic crops became warm and dry in Southwest China, North China, and Northeast China, but warm and wet in the middle and lower reaches of Yangtze River, Northwest China, and South China, whereas the climate in the growth periods of chimonophilous crops became warm and dry in North China, but became warm and wet in Northwest China.  相似文献   

11.
为探讨季节性环境对长爪沙鼠肠道5-羟色胺(5-hydroxytryptamine,5-HT)细胞密度动态的影响,于2003
年11 月(冬季)和2004 年7 月(夏季),采用卵白素-生物素-过氧化物酶复合物(avidin-biotin-peroxidase complex,
ABC)免疫组织化学法,对其肠道5-HT 细胞进行了定位研究。结果显示:5-HT 细胞主要分布于肠上皮基
底部和肠腺上皮中,多呈圆形或椭圆形,少数呈长棒状、锥体形或不规则形,其形态学特征无季节性差异。冬
季在小肠密度最高,十二指肠、盲肠和直肠其次,结肠最低;夏季在小肠和十二指肠密度最高,其它各段密度
相似,这可能与其食物质量的季节性变化有关。除十二指肠和结肠外,冬季肠道各段的密度都高于夏季,这有
利于提高处理和消化食物的能力,是对冬季食物质量和摄食量增加的适应。5-HT 细胞的形态学特征和季节动态
说明,长爪沙鼠肠道在细胞水平上可对环境条件的变化产生反应,具有适应性调节的能力。  相似文献   

12.
Insulin has been extensively studied since it was discovered by Banting and Best in 1921. Early in 1934, Dorothy Crowfoot and John Desmond Bernal obtained the first X-ray diffraction photograph of an enzyme protein: pepsin. In 1935, they took another photograph of a protein hormone: insulin. The chemical structure of protein was unknown until the amino acid sequence of bovine insulin was solved by Fred Sanger and colleagues in 1955. In 1958, the chemical synthesis of bovine insulin started in China through a nationwide collaboration of three institutions: the Institute of Biochemistry in Shanghai, the Institute of Organic Chemistry in Shanghai and Beijing University. The total synthesis of bovine insulin in crystalline form was accomplished in 1965. The success of the synthesis of the first protein in vitro greatly encouraged young researchers in China. Not long afterwards, the project of structural analysis of insulin crystal was carried out in China through the collaboration of the Institute of Biophysics, the Institute of Physics and Beijing University, and succeeded in 1971. In Dorothy Hodgkin's laboratory in Oxford, X-ray diffraction studies of insulin crystals were resumed after about 30 years, and the structure of rhombohedral insulin crystal was solved in 1969. Through insulin research, the Institute of Biophysics in Beijing and the Institute of Biochemistry in Shanghai established scientific collaboration and personal friendship with Dorothy Hodgkin's laboratory in Oxford, and later Guy Dodson's laboratory in York and Tom Blundell's laboratory in London. In 1975, Dorothy Hodgkin wrote a short note, 'Chinese work on insulin' in Nature, anticipating closer scientific exchange between the East and the West. In 1982, a bilateral meeting between the Biochemical Societies in the U.K. and China was held in Oxford. Now, the second bilateral meeting held in Shanghai will further promote the collaboration between our two countries.  相似文献   

13.
利用中国558个气象台站1961-2007年地面气象观测资料,分析了不同区域农业气候资源变化的差异,并分析和比较了1961-1980年(时段Ⅰ)和1981-2007年(时段Ⅱ)的农业气候资源变化特征.结果表明: 与时段Ⅰ相比,时段Ⅱ中国年均气温增加了0.6 ℃,喜凉作物生长期内≥0 ℃积温和喜温作物生长期内≥10 ℃积温分别平均增加123.3和125.9℃·d;1961-2007年,年均气温增幅最大的区域是东北地区,喜温作物生长期内≥10 ℃积温增幅最大的是华南地区.对全国而言,与时段Ⅰ相比,时段Ⅱ在全年、喜凉和喜温作物生长期内日照时数分别减少了125.7、32.2和53.6 h;1961-2007年,长江中下游地区年日照时数的减幅最多,喜凉和喜温作物生长期内日照时数减少量最大的地区分别是华北和华南地区;在全年、喜凉和喜温作物生长期内,中国的降水量和参考作物蒸散量总体均表现为减少趋势,其中,华北地区在全年、喜凉和喜温作物生长期内降水量的减幅均最大,长江中下游地区参考作物蒸散量在全年和喜温作物生长期内的减幅最大,西北地区参考作物蒸散量在喜凉作物生长期内的减幅最大.研究期间,中国气候在全年和喜温作物生长期内总体表现为暖干趋势,其中,喜温作物生长期内西南、华北和东北地区为暖干趋势,长江中下游、西北和华南地区为暖湿趋势,喜凉作物生长期内华北地区为暖干趋势,西北地区为暖湿趋势.  相似文献   

14.
陈淳 《人类学学报》1983,2(4):331-408
通过中国十个重要细石器遗址中细石核的观察,对中国细石核的类型和工艺技术作一初步的区分和综合的比较,以探讨中国细石器传统在时间和空间上的分布特点。同时与发现于东北亚、西北美的细石核进行对比,从它们之间的异同来看这一地区在文化上的传承关系。  相似文献   

15.
A. Islam 《Plant and Soil》1970,33(1-3):533-544
Summary The concentrations of water soluble and ammonium acetate extractable phosphorus in all the soils under investigation first increased and then decreased with time of submergence under rice cropping. The increase in soluble phosphorus in the three acid soils of Luisiana, Casiguran and Guadalupe was related to decrease in the concentration of iron, calcium and reductant soluble phosphates, while in slightly acidic Maahas clay, the increase was associated with decrease in iron and aluminium phosphates. But in the calcareous soil, the increase was due to decrease in the concentration of aluminium and reductant soluble phosphates. The decrease was due to the re-formation of insoluble aluminium, iron and calcium phosphates in Luisiana and Guadalupe clays, to the formation of aluminium and calcium phosphates in Maahas and to the formation of calcium phosphate only in Casiguran fine sand. The application of phosphorus at the rate of 100 pounds per acre produced better tillering, more penicles and higher straw and grain productions in Luisiana, Casiguran and Guadalupe only where the level of soluble phosphate was very low in pots where no phosphorus was applied. This study, thus, indicated the necessity of phosphorus fertilization in low land rice for soils which are low in phosphorus and high in active iron and aluminium.  相似文献   

16.
气候变化背景下1964-2015年秦岭植物物候变化   总被引:1,自引:0,他引:1  
以1964-2015年物候观测数据为基础,选取17种含乔木、灌木及藤本树种为研究对象,分析探讨了气候变化背景下秦岭地区植物物候变化规律及其差异性。结果表明:(1)52年来,秦岭地区物候始期普遍呈提前趋势,提前速率1.2d/10a,物候末期普遍呈推迟趋势,推迟速率3.5d/10a,物候生长期普遍延长;(2)秦岭地区物候突变发生于20世纪80年代,始期于1985年,末期于1984年。突变后,物候特征发生了显著变化,始期的提前速率较突变前显著加快,末期由突变前的提前趋势转变为极显著的推迟趋势,且变化速率和显著性均高于始期;始期与末期变化均表现出"趋同效应";物候年代际变化趋势显示,始期自2001-2005年起提前速率减缓,植物对气候变化的响应表现出适应性及滞后性。(3)秦岭物候变化存在树种差异,3大类树种始期的提前速率呈藤本、乔木、灌木依次增大,而末期的推迟速率则呈藤本、灌木、乔木依次减小。(4)秦岭物候变化存在南北差异,北坡始期的提前速率均高于南坡,而南坡末期的推迟速率均高于北坡。  相似文献   

17.
S F Amakiri 《Acta anatomica》1979,103(4):434-444
Various histochemical and histological techniques were used to study the melanin and dopa-positive cell distribution in the skin of some tropical and temperate breeds of cattle in Nigeria. Melanin pigments were concentrated in the basal and lower spinous layers of the epidermis and in the hair cortex, follicle sheaths and papillae of the various breeds. In the White Fulani and N'Dama breeds, melanin pigments were however found in all layers of the epidermis. Dopa-positive cells (melanocytes) were observed in the epidermis, dermis and hair follicles; the distribution pattern varied among breeds, being copiously disposed in the basal epidermis and papillary dermis in the White Fulani and Muturu and, except in areas of thick epidermal ridges, scanty in the epidermis and dermis of the Friesian and N'Dama. Mast cell distribution pattern in the various breeds was similar to that of the dopa-positive cells. Peroxidase-positive cells were present in the basal epidermis and upper dermis of the Muturu, widespread in the subepidermal layer of the N'Dama and very scanty in the dermis of the White Fulani and Friesian. Acid phosphatase activity was intense in the granular layer of the Muturu and N'Dama breeds and also in the papillary dermis and hair follicles, whereas alkaline phosphatase-positive dendritic cells, and 'clear' cells were also observed in the basal and upper epidermis.  相似文献   

18.
To adapt to seasonal variations in the environment, most mammalian species exhibit seasonal cycles in their physiology and behavior. Seasonal plasticity in the structure and function of the central nervous system contributes to the adaptation of this physiology in seasonal mammals. As part of these plasticity mechanisms, seasonal variations in proliferation rate and neuron production have been extensively studied in songbirds. In this report, we investigated whether this type of brain plasticity also occurs in sheep, a seasonal species, by assessing variations in cell proliferation in the sheep diencephalon. We administered the cell birth marker 5'-bromodeoxyuridine (BrdU) to adult female sheep in July and December, during long and short photoperiod, respectively. The BrdU incorporation was analyzed and quantified in the hypothalamus, a key center for neuroendocrine regulations, as well as in other structures involved in relaying neuroendocrine and sensory information, including the median eminence, the pars tuberalis of the pituitary gland, and the thalamus. In December, 2-fold and 6-fold increases in the number of BrdU+ nuclei were observed in the hypothalamus and thalamus, respectively, when compared with July. This variation is independent of the influence of peripheral gonadal estradiol variations. An inverse seasonal regulation of cell proliferation was observed in the pars tuberalis. In contrast, no seasonal variation in cell proliferation was seen in the subventricular zone of the lateral ventricle. Many of the newborn cells in the adult ovine hypothalamus and thalamus differentiate into neurons and glial cells, as assessed by the expression of neuronal (DCX, NeuN) and glial (GFAP, S100B) fate markers. In summary, we show that the estimated cell proliferation rates in the sheep hypothalamus, thalamus, and pars tuberalis are different between seasons. These variations are independent of the seasonal fluctuations of peripheral estradiol levels, unlike the results described in the brain nuclei involved in song control of avian species.  相似文献   

19.
山东省潍坊地区汉族青少年Heath-Carter法体型研究   总被引:9,自引:0,他引:9  
金利新  朱钦 《人类学学报》2004,23(3):229-232
应用HeathCarter人体测量法对山东省潍坊地区2511名(男1253名、女1258名)7—19岁的汉族学生进行了体型评定。结果是:城市汉族男生平均体型7—15岁为三胚层中间型,16—18岁为内胚层-中胚层均衡型;乡村男生平均体型7—10岁为中胚层-外胚层均衡型,11—14为偏中胚层的外胚层体型,15—17岁为三胚层中间型,18—19岁为内胚层-中胚层均衡型。城市女生平均体型7—9岁为三胚层中间型,10岁为均衡的内胚层体型,11—12岁为外胚层-中胚层均衡型,13—18岁为均衡的内胚层体型;乡村女生7—12岁为均衡的外胚层体型,13—14岁为内胚层-外胚层均衡型,15—18岁为均衡的内胚层体型。  相似文献   

20.
1. The locations of the high affinity uptakes of glutamate, aspartate and GABA were studied autoradiographically and microchemically in slices of hippocampus and septum in vitro. 2. In hippocampus the distributions of the uptake sites for glutamate and aspartate were very similar, with much higher uptake in zones containing pyramidal cell terminals than in other zones. A reciprocal distribution was found for GABA uptake, which was in agreement with that of GAD. 3. Cutting pyramidal cell axons to CAl reduced the uptake of aspartate and glutamate in the target area in CAl by 80%. 4. Autoradiographically the uptake of aspartate was very high in the dorsal part of the lateral septum, moderately high in nucleus accumbens septi and neostriatum, and very low in the medial septum. GABA uptake was lower in the medial than in the lateral septum, but very high in a narrow transitional zone and in the insula Cajella magna. 5. Transecting the axons from hippocampus and subiculum to septum, gave a 70% reduction in the uptakes of aspartate and glutamate in the lateral septum, but no reduction in the medial septum. 6. Literature data on uptake, content and release of glutamate and aspartate in nerve endings in brain are briefly reviewed.  相似文献   

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