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121.
A morphologically interesting hyphomycete was collected from submerged wood in a stream in Doi Suthep-Pui National Park, Thailand. It is described as Aquaticheirospora lignicola gen. and sp. nov., and is characterized by euseptate conidia with divergent arms, which are vertically inserted in different planes to a basal cell. The genus differs from other chirosporous genera in having synnematous conidioma and conidia that are produced on conidiogenous cells borne at the apices of synnemata. The morphological characterization of this new fungus is reported and compared with similar chirosporous genera. To investigate the teleomorphic and phylogenetic relationships of this new taxon, three different regions of the ribosomal gene [18S rDNA, 28S rDNA, and internal transcribed spacer (ITS) including 5.8S] were sequenced and analysed. The results of phylogenetic analyses based on 18S, 28S, and partial ITS including 5.8S rDNA, employing different tree-making methods, indicate that Aquaticheirospora lignicola is closely related to the ascomycetes family Massarinaceae (Order: Pleosporales). The Massarinaceae as currently circumscribed is monophyletic. Massarina australiensis and M. bipolaris , however, appear to belong to the Lophiostomataceae.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 283–296.  相似文献   
122.
In the 17th issue of News from the Biological Stain Commission (BSC) under the heading of Regulatory affairs, the Biological Stain Commission’s International Affairs Committee presents information from the 20th meeting of ISO/TC 212 Clinical laboratory testing and in vitro diagnostic test systems held on October 15 ? 17, 2014 in Toronto, Canada, and from the 29th meeting of CEN/TC 140 In vitro diagnostic medical devices held on February 3, 2015 in Berlin, Germany.  相似文献   
123.
The present study reports the development of 30 polymorphic microsatellite markers for zoysiagrass Zoysia japonica Steud. The 30 markers produced a total of 125 alleles with an average of 4.2 alleles per locus. Values for observed and expected heterozygosities ranged from 0.10 to 0.95 and from 0.15 to 0.81, respectively. At significance threshold (P < 0.05), 11 loci deviated from Hardy–Weinberg equilibrium, whereas significant linkage disequilibrium values were observed between 16 pairs of loci. These markers may provide information needed to select genetically diverse parents for developing breeding and mapping populations of zoysiagrass.  相似文献   
124.
The orchid genus Vanda includes more than 70 monopodial species and numerous hybrids. The aim of this study was to develop microsatellite markers for this horticultural valuable genus. Thirteen polymorphic microsatellite markers were isolated from the variety Vanda Miss Joaquim and were characterized in four Vanda species, 11 Vanda hybrids, and one Aranda intergenus hybrid. Populations from three species were also analysed. Number of alleles ranged from two to 19. For the V. sumatrana population, the expected heterozygosity ranged from 0 to 0.76 (mean 0.31) and the observed heterozygosity ranged from 0 to 1 (mean 0.36). All the varieties tested were distinct from one another (similarity index < 0.8). These microsatellites could be used for studying genetic diversity and population structure of wild populations within the orchid genus Vanda, as well as for distinguishing cultured Vanda varieties.  相似文献   
125.
在氨基甲酸乙酯-氯醛糖麻醉下,经咽部暴露下丘脑。实验在三碘季铵酚制动并人工呼吸条件下进行。用玻璃微电极在细胞外记录下丘脑前部(AH)单位电活动,观察其对颈总动脉注射高渗 NaGl 液及牵拉左心房的反应。共记录到32个单位,其自发放电频率1—13次/s。对照条件下所记录的视上核(SO)单位中,多数对高渗刺激和牵拉左心房分别表现为兴奋和抑制,少数则被前者抑制,而被后者所兴奋。11个下丘脑前核-视上核(Ha-SO)区域的单位,接受高渗刺激后5s 内放电频率增加61.6±37.0%(平均值±标准误),持续时间约1min;偏内侧近 Ha 的单位,在牵拉左心房时其放电频率减少23.5±10.5%;偏外侧近 SO 单位对高渗刺激呈特异的单相反应,此可能即为 Verney 渗透压感受器。AH 偏内侧的 Ha-SO 单位对高渗刺激和牵拉左心房呈会聚反应。对两种刺激引起 AH 单位反应的特征及其整合作用的机理作了简要的讨论。  相似文献   
126.
在采用耳蜗顶部灌流方法测定琥珀酸脱氢酶的活性时,本文提出了两点改进,实验动物为豚鼠:(1)孵育前用2%戊二醛磷酸盐缓冲液(pH7.4,4℃)将耳蜗预固定30min,再冰凉(—20——40℃)约3min,以便消除血管纹屏障,使该部位和柯蒂氏器官的琥珀酸脱氢酶活性能同时被显示出来。(2)在孵育液中加入细胞呼吸抑制剂(阿密妥),可使耳蜗背景色变淡,从而减少假阳性现象。通过对一些豚鼠的实验观察,所得结果基本一致。  相似文献   
127.
The relationships between photosynthesis, dry matter accumulationand translocation have been studied during the development ofthe first true leaf of cucumber. The leaf was grown in an irradianceof 50W m–2 photosynthetically active radiation for 10h–1 at 20 C and 2 g m–3 CO2. The maximum rate of net photosynthesis, on a leaf area basis,occured at full expansion. Photochemical efficiency, based onincident radiation, also increased up to this stage and wasrelated to the concentration of chlorophyll in the leaf. Darkrespiration and the light compensation point fell over the wholeperiod of leaf expansion. A carbon budget analysis showed that the rate of carbon accumulationin the leaf reached a peak at 70 percent expansion. The leafchanged from a net importer to a net exporter of carbon whenit was about 30 percent expanded. The rate of export increasedwith leaf expansion (and with net photosynthesis) and was twiceas high in the day an in the night at full expansion. At fullleaf expansion there was a reduction in the amount of starchlost overnight, and the carbon exported amounted to 80 per centof the daily net carbon fixed. Cucumber, Cumic satinu L., leaf development, photosynthesis, translocation, carbon budget, mineral content  相似文献   
128.
ABSTRACT. This report deals with a group of ciliated protozoa with short ciliary bands found mainly in the cecum of black rhinoceros, Diceros bicornis (Linnaeus, 1758), and white rhinoceros, Ceratotherium simum (Burchell, 1817) from southern Africa. A new genus, Rhinozeta , based on the sum total of the characteristics of seven new related species is described. The species described are R. rhinozeta n. sp., R. triciliata n. sp., R. caecalis n. sp., R. addoensis n. sp., R. cristata n. sp., R. multiplatus n. sp., and R. unilaminatus n. sp. The specific features of the new genus make it incompatible with any of the known families of the Order Entodiniomorphida containing the ciliates present in the digestive tract of herbivorous mammals. This merits the creation of a new family, the Rhinozetidae.  相似文献   
129.
An analysis of the accumulation of water and dry matter in tomato fruit   总被引:24,自引:6,他引:18  
Abstract Previously published data from tomato plants grown in nutrient solutions having one of three electrical conductivities (2, 12 and 17 mS cm?1) were analysed. The rate of water import into the fruit, and the proportion of this conducted by the xylem stream were calculated from the daily rates of transpiration and the net accumulation of water and calcium. The rate of water import decreased as the conductivity of the nutrient solution rose, the maximum daily import rates in the third week after pollination being 3.2, 3.0 and 1.8 g fruit?1 d?1 for fruit grown at 2, 12 and 17 mS cm?1, respectively. During fruit development, the proportion of water imported via the xylem fell from 8–15% to 1–2% at maturity. The principal source of water for tomato fruit growth was phloem sap. Based on the daily rates of net dry matter accumulation, respiration and phloem water import, the calculated dry matter concentration of the phloem sap declined from 7 to 3%, or from 12.5 to 7.8% during fruit development in low or high salinity, respectively. The similar dry matter accumulation of fruit grown at different salinities was due to changes in both volume and concentration of phloem sap. Potassium salts in tomato fruit were calculated lo have contributed –0.29, –0.48 and –0.58 MPa to total fruit osmotic potential in the 2, 12 and 17 mS cm?1 treatments, respectively, which accounted for 38% or 49% of the measured total osmotic potential of the 2 mS cm?1 or 17 mS cm?1 treatments. The contribution of hexoses to total fruit osmotic potential in the young fruit was from about –0.1 to –0.2 MPa at all salinities. The osmotic potential of tomato fruit is regulated more by potassium salts than by hexoses.  相似文献   
130.
The rate of carbon import by tomato fruits has been relatedto their carbon metabolism by examining the effects of fruittemperature on the metabolism of imported assimilates. 14C–sucrose,–glucose, –fructose, –malic acid and –citricacid were injected individually into young growing tomato fruitswhich were subsequently maintained at 25 or 5 °C for 48h. Fruit temperature greatly affected the proportions of 14Clost from the fruits by export and respiration. Only 40 percent of the injected 14C from 14C–sugars and 20 per centfrom 14C–acids was recovered from fruits at 25 °C.Less than 10 per cent of the injected 14C was exported, thebalance being respired. In contrast, more than 50 per cent ofthe injected 14C was recovered from cooled fruits, in whichthe import rate of carbon was presumably reduced, and 20–36per cent of injected 14C was exported. Cooling enhanced thesynthesis of 14C–sucrose from injected 14C–hexosesand inhibited the incorporation of 14C into starch and insolubleresidue. When 14C–sugars were injected, radioactivityexported from the cooled fruits was detected as sucrose in thephloem of the peduncles; radioactivity was also detected instems and roots when fruits were cooled. In almost fully–grownfruits injected 14C–compounds were metabolized less readilythan in smaller fruits. Conversion of 14C–hexoses to 14C–sucrosewas again enhanced by cooling (5 °C, but was less in fruitsmaintained at 35 °C than in controls. Lycopersicon esculentum, tomato, fruit, translocation, carbon metabolism  相似文献   
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