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1.
署名     
《微生物学杂志》2006,26(6):35-35
论文的作者应在发表的作品上署名。署名者可以是个人作者、合作作者或团体作者。1署名是拥有著作权的声明。《中华人民共和国著作权法》规定:著作权属于作者。著作权包括发表权、署名权、修改权、保护作品完整权等。署名权即表明作者在作品上署名的权利;署名表明作者的劳动成果及作者本人都得到了社会的承认和尊重,即作者向社会声明,作者对该作品拥有了著作权。2署名是表示文责自负的承诺。署名即表明作者愿意承担责任。3署名便于读者与作者联系。署名即表明作者有同读者联系的意愿。  相似文献   

2.
《植物分类学报》2005,43(4):323-324
块根2。茎直市。基生叶不存在;叶片掌状深裂,一回裂片浅裂。花小;上萼片船形或船状盔形。花瓣无距或有很短的距。唇明显。种子只沿棱生翅,无横膜翅。  相似文献   

3.
《生物磁学》2013,(35):I0001-I0002
据英国媒体10月21日报道。英美两国科学家通过克隆人类皮肤细胞。创造新的毛囊。有望彻底解决脱发、谢顶难题。这一研究成果已经在美国《国家科学院院刊》上发表。  相似文献   

4.
《中国真菌学杂志》2014,(4):221-221
按GB 3358-82《统计学名词及符号》的有关规定书写,常用如下:①样本的算术平均数用英文小写互(中位数仍用M)。②标准差用英文小写s。③标准误用英文小写sx。④t检验用英文小写t。⑤F检验用英文大写F。⑥卡方检验用希文小写疋。。⑦相关系数用英文小写r。⑧自由度用希文小写口。⑨概率用英文大写P(P值前应给出具体检验值,如t值、X^2值、q值等)。以上符号均用斜体。  相似文献   

5.
《生命世界》2006,(1):34-37
沙皮犬(Shar-Pei)世界上最稀少的犬,原产我国广东。至今已有2000多年历史。因为皮肤宽松多褶、毛短而硬、酷似沙皮而得名。被毛短密、粗硬、颜色有浅黄、宗黄和米色、黑色等。体高46~51厘米。体重18~25千克。头硕大呈方形,嘴部宽长,舌头为特殊的紫蓝色,耳朵小并且向前下垂,眼睛深邃,凹藏于眼窝内。脖颈短而粗壮。躯干呈圆筒状。四肢结识,尾巴上扬。全身肌肉发达。沙皮犬从外表看似沉郁、凝重,但性格顽皮,忠实可爱。它们是原始的、充满热情的犬。在生人面前它们显得拘谨、警惕,随时做好防御的准备,但它们决不会主动发动攻击。它们还是一种讲卫生的家庭宠物犬。  相似文献   

6.
五年来,在美国先后出现了一百五十个从事生物工艺学研制的公司。这些公司生意兴隆、财政富裕。在欧洲各国成立的生物工艺学公司也是如此。毫无疑问,生物工艺学具有美好的前景。财政界已开始认识到发展生物工艺学工业的重要意义。  相似文献   

7.
潘云唐 《化石》2009,(1):43-53
杨钟健院士离开我们整整30年了。他的得意门生、亲密朋友刘东生院士也于去年离开了我们,他们间的深情厚谊令人们永远传颂。刘东生1942年毕业于西南联合大学地质地理气象系。早年曾从事抗日救亡工作。1946年2月进入重庆北碚经济部中央地质调查所。7月,他随该所迁回南京。当年年底,李春昱所长找刘东生谈话,对他说:“现在工程地质很重要。这在将来铁路、水坝等工程里是迫切需要的。……”李所长最后提出建议刘东生也从事工程地质研究。  相似文献   

8.
《植物分类学报》2005,43(4):324-335
块根2,或较多,束生。茎直立,偶尔蔓生或上部缠绕。基生叶不存在;茎下部叶在开花时枯萎;叶片掌状深裂,少有全裂。一回裂片浅裂。侧萼片长在1cm以上;上萼片盔形、高盔形,少有船形。花瓣瓣片不膨大,有距,唇明显。种子有膜质横翅。  相似文献   

9.
<正>什么是good science?Good science也许被低估了。它可能不是那么华丽炫目,但是它带来革新。它开启了新的可能性。它告知,它启发,它创造。快来加入Takara和Clontech,一次一个实验,一起传颂这些生命科学研究的故事,是它们把世界变得更美好。科学领域,每个决定都有着深远的影响…每个时刻都是一个机遇,把一个实验最深的意义挖掘出来。决定很重要,无论是实验设计还是数据分析。这是我们通过经验确认的;我们是科学家。  相似文献   

10.
《植物分类学报》2005,43(4):337-354
块根2。茎缠绕。基生叶不存在;叶片掌状深裂至全裂,一回裂片浅裂至细裂。上萼片通常盔形或高盔形。花瓣的瓣片大,上部常膨大,有短或长距。种子有横膜翅。  相似文献   

11.
Makoto Kato 《Oecologia》1988,76(3):364-370
Summary Three Japanese species of Impatiens, which secrete nectar continuously in long spurs, were visited by Bombus diversus workers consecutively throughout the day. B. diversus workers showed characteristic patterns of behavior in flower use, flower choice, and patch departure. (1) Bumblebees stayed longer on a flower which had been unvisited for a while than on a flower which had been visited recently. (2) Bumblebees preferred visiting flowers which had been unvisited for a while to visiting those which had been visited recently, and to visiting those which had been unvisited for a long period. (3) Bumblebees had a higher probability of leaving a patch after they had stayed on a flower for a short period than after they had stayed for a longer period. The bumblebees appeared to perceive both remotely and proximately chemical cues deposited by other foraging individuals, which indicated nectar rewards in a flower, and thus obtained a higher nectar intake than the mean amount of nectar left in a flower.  相似文献   

12.
High‐altitude and high‐latitude sites are expected to be very sensitive to global warming, because the biological activity of most plants is restricted by the length of the short snow‐free season, which is determined by climate. Long‐term observational studies in subalpine meadows of the Colorado Rocky Mountains have shown a strong positive correlation between snowpack and flower production by the forb Delphinium nuttallianum. If a warmer climate reduces annual snowfall in this region then global warming might reduce fitness in D. nuttallianum. In this article we report effects of experimental warming on the abundance and flower production of D. nuttallianum. Plant abundance (both flowering and vegetative plants) was slightly greater on warmed than control plots prior to initiation of the warming treatment in 1991. Since 1994 experimental warming has had a negative effect on D. nuttallianum flower production, reducing both the abundance of flowering plants and the total number of flowers per plant. Flower bud abortion was higher in the heated plots than the controls only in 1994 and 1999. Results from both the warming experiment and analyses of unmanipulated long‐term plots suggest that global warming may affect the fecundity of D. nuttallianum, which may have cascading effects on the pollinators that depend on it and on the fecundity of plants that share similar pollinators.  相似文献   

13.
Hurricane disturbance may have strong effects on plant-animal interactions important in plant reproductive success. Components of reproductive success (flowering, pollination, seed predation) in the tropical shrub Ardisia escallonioides (Myrsinaceae) were examined from 1991–1994 in four southern Florida populations. Hurricane Andrew struck three of the four populations on 24 August 1992. Hurricane Andrew delayed flowering by two months in 1992. In 1993 and 1994, the three hurricane-damaged populations had increased flowering and inflorescence production compared to 1991 and 1992, while the undamaged population had no flowering. Hurricane disturbance had different effects on generalist versus specialist plant-animal interactions. Species composition and relative abundance of the generalist pollinator community that visits A. escallonioides was similar before and after the hurricane, indicating little effect of the disturbance on this interaction. In contrast, populations of a specialist flower galling moth (Periploca sp., Cosmopterigidae) declined in 1992 following Hurricane Andrew. Although moth populations increased at two of the three sites in 1993, the relative impact of moth predation on seed production was low due to extensive flower production. One moth population suffered local population extirpation for two years, reestablishing itself in November 1994. Hurricane disturbance resulted in a window of opportunity for massive seed production of Ardisia escallonioides in south Florida. Total seed production in 1993 increased twelve to seventy-three times the 1992 levels. Total seed production declined in 1994, but remained high compared to prehurricane levels.  相似文献   

14.
Putrescine, at 0.5 mM, was found to induce flower buds in 98%of seedlings of Pharbitis nil cv. Kidachi grown hydroponicallyin non-nutrient tap water. Cadaverine and unnatural 1,6-diaminohexanealso induced flowering in 100% of seedlings at 0.5 and 1.0 mM,respectively, and they were found to increase the putrescinecontent in the treated plants concordantly with flower induction.Spermidine was detected in the plant extracts, but a changein its titer was not observed between the treated and untreatedplants. Spermine, 1,3-diaminopropane and cadaverine were notfound. Both the biogenic and non-biogenic diamines were thoughtto drive a common biochemical process to cause flowering. (Received November 16, 1993; Accepted January 27, 1994)  相似文献   

15.
To understand the factors that induce floral senescence in Hibiscus syriacus L., we have investigated the effects of various chemical agents on flower senescence at two different flowering stages, before and after full bloom, as well as the relationship between flower longevity and endogenous ethylene production before full bloom. Treatments with ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), and ethephon enhanced floral senescence, while aminoethoxyvinylglycine (AVG) promoted flower longevity regardless of treatment timing. Although ethanol slightly extended flower longevity, abscisic acid (ABA), nitric oxide, boric acid and sucrose, which have been reported to affect flower longevity or senescence, had no effect on H. syriacus floral senescence. The polyamine spermine (SPM), methylglyoxal-bis(guanylhydrazone) (MGBG), an inhibitor of SPM biosynthesis, and cycloheximide (CHI) accelerated flower senescence when applied before full bloom, but had no effect when applied after full bloom. SPM, MGBG and CHI treatments resulted in enhanced ethylene production during flower opening, and the promotion of flower senescence is mediated by ethylene production prior to full bloom. Furthermore, endogenous ethylene, spontaneously produced before blooming, was closely associated with floral senescence. These results suggest that ethylene production during flower opening plays a key role in determining the timing of Hibiscus flower senescence.  相似文献   

16.
The ability of green parts of Cox's apple flowers (sepals, receptacleand pedicel) to photosynthesise was demonstrated using 14CO,feed experiments and an infra-red gas analysis (IRGA) system.The sepals had the greatest ability, comparable with that ofleaves, followed by the receptacle. Sepals and leaves fixedthe same amount of CO2 in the dark. Photosynthesis and respirationrates in orchard flowers were measured in comparison to thoseof leaves. Flower gross photosynthesis (GP) was about a thirdof that of leaves at the balloon stage and 15 d after full bloomin 1987, but this ratio was much less at full bloom (FB) inthe same year. GP in flowers decreased rapidly with fruitletenlargement. It was estimated that flower photosynthesis significantly contributedto their carbohydrate balance (15-33%) during the floweringand fruit setting periods. The highest contributions were made at the green cluster stage(33%) and between 6 and 11 d after FB (27%), the period whenthe fruit set had been initiated. Removal of sepals, the mainphotosynthetic parts of the flower, at the pink bud stage decreasedinitial set. The results suggest that flower photosynthesismight play an important role in flower growth and fruit setting.Copyright1994, 1999 Academic Press Apple, photosynthesis, respiration, fruit setting, flower photosynthesis, sepal removal  相似文献   

17.
We studied various aspects of the fruiting biology of Cornus sanguinea (Cornaceae), a fleshy-fruit-producing deciduous shrub, in four populations in northwest Spain. One population was studied over a 5-yr period (1989-1994), and the remaining populations in 1994 only. Fruit-set level varied among years (range 11-18%) and among populations (range 8-22%), but was in all cases low. Within plants, fruit-set level did not vary significantly among inflorescences, indicating that inflorescence fruit set is independent of inflorescence position and inflorescence, phenology. To investigate the function of surplus flowers, we carried out flower removal experiments. Inflorescence fruit-set level was unaffected by removal of up to =75% of flowers. These results suggest that Cornus sanguinea regulates its fruit-set level via plasticity in the number of fruits aborted: if flower mortality has been high, fewer fruits will be aborted. Within the inflorescence, surplus flowers thus act as insurance against flower loss.  相似文献   

18.
We estimated selection on three morphological characters in the hermaphroditic, hawkmoth-pollinated orchid Platanthera bifolia and explored selection surfaces through male and female function. The work was carried out in northern Sweden during two flowering seasons (1994 and 1995) in one natural population and one season (1995) in another natural population. Fitness was estimated as number of pollinia removed (male function) and number of fruits produced (female function). We detected directional selection towards larger inflorescence size (flower number) through both sex functions in both populations in 1995. In 1994, with an unusually dry growing season, 78% of the individuals failed to set any fruit, and there was selection for larger inflorescences only through male function. In this year, there was selection towards longer flower spurs, which could be a direct or indirect effect of spurs being shortened by drought. The results demonstrate that selection patterns may vary temporally and spatially, and that the 'male function hypothesis' may be applicable as female function is more resource dependent than male function.  相似文献   

19.
利用体视显微镜、半薄切片和超薄切片法对倒地铃(Cardiospermum halicacabum Linn.)雄花和假两性花开花过程及花药发育过程进行了观察和比较研究。结果显示:(1)花蕾发育早期,倒地铃雄花和假两性花的花蕾形态没有区别;花蕾发育后期,雄花雌蕊退化,假两性花雌蕊继续发育,花蕾外部形态出现差异;开花时雄花花药开裂,假两性花花药不开裂。(2)倒地铃雄花和假两性花均具四室花药,呈蝶形;花药壁细胞从外到内依次是表皮、药室内壁、中层(2层)和绒毡层;花药壁发育为基本型,绒毡层为单核分泌型,四分体为四面体型,花粉粒两核;开花时雄花和假两性花中层都有残留;小孢子液泡化时,绒毡层开始降解,两核花粉粒时,假两性花绒毡层降解较快。(3)雄花药室内壁次生加厚完全,裂口区发育,连接同侧花粉囊的连接组织降解,花药开裂;假两性花药室内壁次生加厚不完全,具唇形细胞,药隔细胞壁未降解,同侧花粉囊未连通,花药四室,不开裂;假两性花成熟花粉粒细胞质稀少,内壁不完整。本研究结果表明,倒地铃的雄花是由两性花在发育早期雌蕊停止发育形成的,假两性花则由两性花在发育晚期雄蕊功能退化造成的。  相似文献   

20.
Development of a control strategy for thrips attacking nectarine trees depends on an understanding of their phenology, distribution, and life history as related to characteristics of nectarine orchards. To this end, we compared the overwintering behavior, distribution, and abundance of western flower thrips, Frankliniella occidentalis (Pergande), among 11 nectarine orchards located in the dry central interior of British Columbia, Canada, during 1993 and 1994. Western flower thrips emerged from areas not previously used for agriculture (wild areas) and from within orchards before trees were out of dormancy. Flight of thrips within and around orchards peaked during early bud development, with a second major peak several weeks later after husk fall as the next generation emerged. Orchards protected from wild areas by other orchards had the lowest densities of thrips in buds. Density estimates of western flower thrips on trees were not affected by location of trees within orchards or buds within trees, but most thrips were found in the most developed buds on a tree at any one time. Thrips were not found within buds until petal was first visible on the buds. Larval feeding on buds at early petal fall resulted in serious surface russetting of fruit.  相似文献   

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