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121.
122.
S-a, S-b and S-c are three loci for F1 pollen sterility in cultivated rice (Oryza sativa L.). Taichung 65 (T65) is all Sj/Sj at these three loci, while its F1 pollen sterile near-isogenic lines, TISL2 (S-b), TISL4 (S-a) and TISL5 (S-c) is Sj/Sj according to their respective sterility locus. Using SSR molecular marker to detect the segregation of the allele Si and Sj in pollen calli population induced from different hybrid F1, which have different pollen sterility locus, showed that the segregation of allele Si and Sj was distorted. The distorted direction of pollen calli population in vitro was not the same as F2 population in vivo. The quantities of pollen callus carrying Sj were much more than that of carrying Siat S-a and S-c locus, the ratio of Si and Sj were 1:4.81 and 1:1.96 respectively. But the opposite tendency was observed at S-b locus, the ratio of Si and Sj being 1:0.35. At the same time, all these results were undisturbed by either culture medium or culture period.  相似文献   
123.
124.
Thyroid hormone profiles and 5-monodeiodinase activity were determined in tilapia at different stages of early development. The results showed that both T4 and T3 were present in significant amounts in fertilized eggs. There was a steady decrease in both T4 and T3 levels during embryonic development. The levels continued to decline after hatching until around 7 days later when most of the yolk had been absorbed. The T4 level started to rise then, suggesting that the larval thyroid had begun to produce T4 at this time, which coincided with the period of faster growth of the larvae. The T3 level remained fairly constant until around 20 days after which it rose significantly. In vitro determination of 5-monodeiodinase activity (5-D activity) in the whole-body homogenates of larvae showed that the enzymatic conversion of T4 to T3 was not detectable in eggs and 3-day-old larvae but detected in 5-day-old and older larvae. There was a gradual increase in the Vmax as development proceeded indicating increasing 5-D activity during larval development. The Km values did not differ significantly in the different stages of development. These results are discussed in relation to the growth and development of the larvae.  相似文献   
125.
Extract

Although this topic has traditionally been discussed in textbooks of biochemistry under this heading, an enormous volume of work in this area on the metabolic fate of drugs and insecticides over the last twenty years shows it to be a somewhat misleading title and the designation of this area of study by the newer term “xenobiochemistry” turns out to be much more justifiable than it would seem at first sight. When the biochemical mechanisms that deal with foreign, unnatural or xenobiotic compounds are investigated in detail, the enzymes concerned are usually found to be quite separate from those which handle the ordinary substrates and cycles on which normal economy of the animal body depends.  相似文献   
126.
1.?The effect of different amounts of added manganese (Mn) (0, 10, 20 and 40 mg/kg) in inorganic and organic form and phytase (0 and 300 U) was investigated on productive, reproductive and haematological traits on 480 hens and 60 cocks (Inchas breeds) divided into 12 groups: 10 and 20 Mn × 0 and 300 phytase × 2 Mn sources (8 groups), two negative controls (0 Mn × 2 levels of phytase) and two positive controls (40 Mn × 2 Mn sources).

2.?Phytase supplementation increased laying rate by 1·1% and egg weight by 0·4 g.

3.?Manganese supplementation at 10 mg/kg over dietary sources improved hatchability, at 20 mg/kg decreased death embryos and abnormality as those of hens supplemented with 40 mg/kg Mn. Inorganic Mn at 10 mg/kg significantly increased egg mass compared to the organic form. Inorganic Mn was more efficient in decreasing abnormal chicks than organic Mn. Phytase supplementation significantly increased hatchability of fertile eggs and decreased the number of abnormal chicks of groups fed on diets unsupplemented with Mn and those supplemented with 10 mg/kg Mn.

4.?Mn supplementation at 10 mg/kg over dietary sources significantly improved sperm mass motility and decreased abnormal sperm. Phytase significantly decreased lymphocyte cells and plasma AST.

5.?Mn supplementation of the control diet (containing only 16 mg/kg from raw materials) with 20 mg/kg of Mn from either organic or inorganic source is adequate to support egg production traits, egg quality, reproductive traits and economic efficiency of dual purpose cross-bred hens; however, phytase supplementation may reduce the required Mn supplementation to 10 mg/kg.  相似文献   

127.
128.
The examinations of caterpillars migrations ofLymantria monacha 1974/75 in respect of biophysical food-sources: food (RF) of zones of earth radiations (RZ) and food (NF) of normal zones (NF) in connection to certain developmental stages with cut branches of spruces and the possibility of movement in West-East direction (Jahn, 1977) were repeated 177/78 with living plants (Larix japonica) in North-South direction. It could be stated, that also the direction North-South was of certain influence on caterpillars migrations. In respect to food the results 1977 were like those from 1974/75 (RF in RZ) and of preceding mortality investigations. But 1978 the results some-what contrasted with the former ones. The behaviour 1978 might correlate with increasing solar-activity in this year, like thisBecker (1980) found for the feeding activity rhythms of termites in 1978 and 1979. The attraction of the food-sources in the ranges investigated: RZ South — NZ North and NZ South — RZ North was similar in northern and southern larch-stands, somewhat promoted or restricted, as some controls showed, from the influence of direction. It could be proved on spruces lying in fluctuating zones (sudden changes of RZ and NZ) for the attack of scolytid beetles besides volatiles attractants of bark and already breeding beetles (pheromones) and climate condition also biophysical fields are of importance. A good coincidence was given between attacked stem-regions and RZ during cool weather conditions. But when warm weather was prevailing — this only could be stated for the beginning of the flight period. Probably attractants of bark and beetles released more concentrated are responsible for an extent of invasion of the scolytids from RZ to NZ. In gradation areas ofCephalcia abietis in “Waldviertel” (Lower Austria) where this pamphyliid causes severe damages on spruces inside of RZ or fluctuating zones, in soils of fluctuating zones larvae in state of latency were more numerous in NZ than in RZ. It is assumed that strong influence of biological fields does not be favourable for larvae in these states.  相似文献   
129.
Zusammenfassung An jungen Fichten 9 verschiedener Kreuzungen wurde das Vorkommen von Gallen vonSacchiphantes abietis L. untersucht. Es traten genetisch bedingte Unterschiede in der Stärke des Gallenbefalls auf. Die Häufigkeit der Gallen war nicht vom Zeitpunkt des Knospenaustriebs abhängig. Fichten mit Gallenbesatz hatten im Durchschnitt besseren Höhenzuwachs als Bäume ohne Gallen. Gallen m Gipfeltrieb hemmten den Höhenzuwachs. Die Stärke des Gallenbefalls war positiv von dem Vorkommen von Prolepsis beeinflußt. Es bestanden Beziehungen zwischen der Häufigkeit der Gallen und der Anzahl überwinterder Läuse.
Differences in attack of the spruce gall aphid Sacchiphantes abietis L. in a Norway spruce progeny trial
The occurence of galls caused by the spruce gall aphid (Sacchiphantes abietis L.) was studied on young Norway spruce progeny from 9 different full sib families with parents from Sweden and Western Europe. The frequency of galls was found to vary significantly with genetic origin. Time for bud flushing did not influence the frequency of galls. Attacked trees had on verage better height increment than trees without galls. Galls on the leading shoot reduced height increment. The frequency of galls was positively influenced by the occurence of prolepsis. The abundance of hibernating aphids was positively correlated to the frequency of galls.


Mit 4 Abbildungen und 6 Tabellen  相似文献   
130.
本文主要论述二十世纪遗传学的兴起,及其对于人类社会的影响。它与达尔文的进化论共同形成一个完整的生物体系:进化论是宏观的,遗传学则是微观的;正如牛顿力学与卢瑟福的原子结构学说一起,形成一个完整的宏观、微观物理体系一样。但是遗传学是由一系列重大的发现与突破所形成的,不能用一个人名概括。这里包含着孟德尔的粒子遗传定律和摩根的基因论、艾弗里的脱氧核糖核酸为遗传的物质基础的发现,沃森克里克的核酸双螺旋结构的阐明,和尼伦堡与奥巧阿的遗传密码的破译。这一破译可以说是生物学中最伟大的发现,因为它揭示了遗传信息所赖以在生物体中书写的语言,即核酸中的四种碱基如何形成蛋白质中二十种氨基酸的语言。从理论上来说,遗传学挽救了进化论,奠定了物种同源的物质基础,及自然选择的实验依据,从实践方面,它提供了动植物质量和数量性状改良的理论和方法。此外,它与由之而衍生的细胞工程和基因工程在一起,为人类今后创新型的生物开拓了光明的前景,可以医治遗传疾病,产生新型的器官,育成高产优质的经济生物品种,大大丰富人类的社会生活,这些都是正在和不久可以逐一实现的。  相似文献   
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