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71.
We studied the effect of the common ascidian Styela clava on the growth of small holothurians of the species Apostichopus japonicus (Selenka, 1867). In a traditional aquaculture system, the oxygen consumption rates, ammonia excretion rates, and ingestion rates of small A. japonicus were reduced significantly, which suggested that this group was stressed by the presence of large A. japonicus, and that this stress grew stronger with time. Oxygen consumption rates, ammonia excretion rates, and ingestion rates of small A. japonicus in an integrated aquaculture (IA) system with S. clava, microalgae, and A. japonicus were higher than those observed in the traditional culture system. Metabolic and digestive enzymes were more active in small A. japonicus in the IA system than in those in the traditional aquaculture system. These results suggest that the IA model did not affect the growth of large A. japonicas, but produced a marked positive impact on the growth of small individuals. 相似文献
72.
Kazuko Hase Masakazu Shimada 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(1):236-242
In anurans, female polyandry under male harassment is distributed across taxa because of external aquatic fertilization. According to the sexual selection theory, male–male competition for access to females is affected by the operational sex ratio (OSR) and population density. The Japanese common toad, Bufo japonicus, is widespread in mainland Japan, and like the European common toad, B. bufo, it engages in explosive breeding. In this study, we observed the breeding behaviour of B. japonicus in isolated local populations for over four years in two breeding ponds with different population sizes and densities: large‐low (L‐pond) and small‐high (S‐pond). We analysed the relative polyandry ratio in egg clutches laid by females and estimated the size‐assortative mating pattern to be an indicator of male–male competition in the two ponds. Both ponds tended to exhibit a size‐assortative mating pattern; however, the frequency of polyandry was different in the two ponds (L‐pond = 20% and S‐pond = 90%). Our results showed that polyandry could occur without multiple amplexus with a high population density, i.e. eggs were often fertilized by free‐swimming sperm in the small shallow pond. We propose that high female polyandry ratios without continuous male harassment are generated because of a male‐biased OSR and a high population density in the small pond. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 236–242. 相似文献
73.
74.
日本续断中新五糖皂甙的结构及其核磁共振光谱 总被引:1,自引:0,他引:1
从日本续断(Dipsacus japonicus Miq.)根的乙醇提取物中分得一个新的三萜皂甙,其结构被鉴定为3.-O-〖β-D-吡喃葡萄糖(1→)〗〖α-吡喃鼠李糖(1→3)〗-β-D-吡喃葡萄39糖(1→3)-α-L吡喃鼠李糖(1→2)-α-吡喃阿拉伯糖-齐墩酸。采用一维SEMDY谱和转坐标NOE差谱核磁共振新技术相结合的方法,对糖体间和9糖体与甙元间的连接顺连接位置进行了研究。该方法的结果 相似文献
75.
76.
从贵州省宽阔水自然保护区采到的日本亮耳菌Lampteromycesjaponicus(Kawam.)Sing.这一中国新记录种,其菌丝体及其丙酮粗提物对线虫有毒杀作用,是一类有应用前景的食线虫真菌资源。 相似文献
77.
78.
Lotus japonicus , a model legume plant, was reviewed and compared with Medicago truncatula and soybean. Several mutant libraries are being analyzed, focusing on the nodulation mechanism. The first plant nodulation
gene nin was cloned by Ac-transposon tagging. Soybean remains as the most studied legume, especially in relation to the disease resistance genes. However,
Lotus japonicus offers several advantages for molecular genetics, and the remained lackings were recently filled up, namely 1) an appropriate
crossing partner for Gifu, accession Miyakojima, was proposed for its 4% polymorphism and smooth recombining ability; 2) a
genome library with long inserts, average of 140 kb, and 8.2 genome equivalents of library size, has been established; and
3) the rather low polymorphic rate between Gifu and Miyakojima can be overcome with the HEGS (High Efficiency Genome Scanning).
With this infrastructure, positional cloning of the causative genes of several mutant libraries will be accomplished in a
short term. Genome sizes of L. japonicus acc. Gifu and Miyakojima were determined with high accuracy, to be 494±0 MB and 512±1 MB, respectively. The feasibility of
constructing a physical map of the entire genome, for functional genomics, was discussed.
Received 5 September 2000/ Accepted in revised form 11 October 2000 相似文献
79.
Lotus japonicus possesses certain characteristics suited to molecular genetic and genomic analyses and has been adopted as a model species
in the study of legume plants. To make a catalogue of genes expressed in L. japonicus and understand biological processes specific to legume plants, large scale EST analyses have been performed. To date, more
than 26,000 EST sequences of L. japonicus have been deposited in the public databases. These sequences were developed by five laboratories using different organs.
In this review, information obtained from two EST projects carried out in Japan is presented. Some 7137 non-redundant EST
groups from young plants and 718 groups from flower buds were generated. A similarity search revealed that homologues of nodulin
genes in other legume plants, as well as genes related to secondary metabolism, seed development and the reproductive process,
were included in the EST collection, indicating the usefulness of the EST clones in the study of biological phenomena distinctive
to legume plant species.
Received 23 August 2000/ Accepted in revised form 22 September 2000 相似文献
80.
The hatching dates of Encrasicholina punctifer and Engraulis japonicus larvae collected in the coastal waters off Tanshui River Estuary during the fishing seasons of 1992 and 1993 indicated that these two anchovies had protracted spawning seasons, which resulted in multiple recruitment cohorts. Encrasicholina punctifer larvae recruited to the estuary from October to March, while the majority of E. japonicus larvae came in March-May and to a lesser extent in October and November. The E. punctifer larvae on arrival to the estuary were 17·4–35·6 mm in length, 167ndash;89 days old and had growth rates of 0·4–1·0 mm day−1 , E. japonicus larvae were 12·1–32·7 mm in length, 19–62 days old and had growth rates of 0·7–0·9 mm day−1 . Growth rates were significantly different among cohorts and positively correlated to water temperature. 相似文献