全文获取类型
收费全文 | 138篇 |
免费 | 3篇 |
国内免费 | 3篇 |
出版年
2015年 | 2篇 |
2013年 | 1篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 4篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1964年 | 1篇 |
1961年 | 2篇 |
1959年 | 4篇 |
1958年 | 9篇 |
1957年 | 5篇 |
1956年 | 3篇 |
1955年 | 5篇 |
1954年 | 4篇 |
1953年 | 1篇 |
1952年 | 1篇 |
1951年 | 5篇 |
1949年 | 4篇 |
1948年 | 5篇 |
排序方式: 共有144条查询结果,搜索用时 46 毫秒
1.
2.
Geographical variation in mandible morphologies specialised for collembolan predation depend on prey size in the ant Strumigenys lewisi
下载免费PDF全文
![点击此处可从《Ecological Entomology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
KYOHSUKE OHKAWARA KAZUKI NAKAMURA NATSUMI KADOKURA TAKAAKI TERASHITA 《Ecological Entomology》2017,42(2):156-163
1. Ants in the genus Strumigenys are predator ants that feed on tiny soil arthropods. The mandibles are modified into high‐speed traps to capture swift collembolan prey. The peculiar mandible morphologies of these ants have evolved depending on characteristics of the prey. Specifically, the evolution of mandible size and shape may be directly driven by prey size. 2. In the present study, the intraspecific variation of the morphological traits of Strumigenys lewisi populations were observed in central Japan. The relationships between the morphological variations and the prey body size were analysed. 3. In workers and queens, three morphological traits, head width, mandible length, and mandible width were significantly different among the multiple sites. Specifically, the mandible length was shorter in southwestern Japan than in other sampling locations. The ancova model revealed that the allometry of the mandible length to the head width was different among the sites. 4. As predicted, the mandible length was positively correlated with the average body size of collembolans in the Entomobryidae family. Furthermore, multiple regression analysis showed that the variation of the mandible length was affected by environmental factors represented as location information. However, the effect of collembolan body size was more effective at predicting mandible length. The study suggests that the geographical variation of mandible morphologies in S. lewisi has been selected by predator–prey interactions with collembolans. 相似文献
3.
MASAHIRO SATO SHUN-ICHIROH OGATA RYUZO UEDA REIKO NAMIKAWA TOSHITADA TAKAHASHI TAKAO NAKAMURA EIICHI SATO TAKASHI MURAMATSU 《Development, growth & differentiation》1983,25(4):333-344
C-9-1, a monoclonal IgM antibody raised against human null cell acute lymphocytic leukemia cells reacted with restricted regions of embryonic and adult tissues of the mouse. The antigen positive sites in the embryos included embryonic ectoderm, visceral endoderm, trophoblastic cells invading the maternal decidua of 5∼7-day embryos, primordial germ cells of 10∼12-day embryos, epithelium of nasal chamber, the bronchus, Mullerian duct, epididymis and bladder of 12∼17-day embryos. In the adult mice, C-9-1 antigen was detected in renal tubules, a part of stomach, bladder, endometrium and epididymal sperm. Embryonal carcinoma cells, but not endodermal cells of teratocarcinoma expressed the antigen. Thus, C-9-1 antigen showed distribution similar to SSEA-1. However, C-9-1 antigen was not detected in preimplantation embryos, nor in oviduct, both of which are positive for SSEA-1. 相似文献
4.
KATSUYUKI SATO 《The Journal of eukaryotic microbiology》1989,36(1):35-38
Two new phenomena were observed during macronuclear development in E. patella. During the formation of giant chromosomes, the number of chromosomes decreased while individual chromosomes gradually became longer and thicker. Immediately before macronuclear elongation, ring-like anlagen appeared, which did not contain chromatin at their centers. The course of macronuclear development in Euplotes is reconsidered in light of these findings. 相似文献
5.
ABSTRACT. Microsporidian spores were developed from cells which were grown in vitro from a human liver lesion which was due to larval Echinococcus multilocularis . The microsporidian spores developed in the same fashion as an Encephalitozoon cuniculi . The Encephalitozoon -like spores were completely separated on Percoll gradients. The separated spores contained DNA capable of amplification by two different primer sets designed for the polymerase chain reaction (PCR) of E. multilocularis DNA. However, the cell DNA from which microsporidium developed was thoroughly insensitive to the PCR using the E. multilocularis primer sets. The results strongly suggested that Encephalitozoon should be taken into consideration, when DNA isolated from larval E. multilocularis is analyzed. 相似文献
6.
7.
8.
Experimental studies on parasitization by Apanteles glomeratus. 总被引:1,自引:0,他引:1
YOSHIBUMI SATO 《Physiological Entomology》1979,4(1):63-70
ABSTRACT. The host-finding sequence of Apanteles glomeratus females and the factors involved in it were analysed. A female wasp is attracted by the leaf odour of the food plant of the host ( Pieris rapae crucivord ). She then walks slowly with the tips of her antennae rubbing the leaf surface. When she comes across damage produced by the host's feeding, her antennae are raised and she turns towards the damage. She often then erects her wings and/or bends her abdomen forward in response to a chemical produced from the leaf by the host's saliva. Long-lasting searching elicited by this odour normally leads to an encounter with a host caterpillar, whereupon odour from the host itself releases opposition. Host saliva, faeces and silk are also involved in these responses, but the response to fresh leaf damage has the most specific function in the overall strategy of host-finding. 相似文献
9.
Yukiko?MATSUURAEmail author Yoshihiko?SASAMOTO Kenji?SATO Yoshiyuki?TAKAHASHI Masatsugu?SUZUKI Noriyuki?OHTAISHI 《Ecological Research》2004,19(4):397-404
The ovarian cycle and conception of sika deer were studied to reveal factors responsible for delayed conception. Concentration of progesterone in feces from 12 female Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) was measured during the mating season in 2000. The cyclic pattern of fecal progesterone synchronized with estrous symptoms, which could hence be interpreted as indicating ovarian cycle. All observed females ovulated by 14 October. However, during the early mating season, females did not permit copulation at ovulation, and the length of luteal phase following ovulation without estrus was 9.8±4.6 days (5–24days). Most females conceived at the first copulation, which were confirmed by progesterone profiles that was sustained at a high level after the copulation. This indicates the presence of a functional corpus luteum, a state of pregnancy. Thus, some females had repeated ovulation without copulation several times, creating a 3–4week variation in the timing of conception. But some females conceived very late in the mating season after the repetition of ovulation and copulation. 相似文献
10.
Several indices of reproductive skew, which quantify the degree of unequal partitioning of reproductive output among members
in an animal society, have been proposed. Here we point out the drawbacks of these indices. The most serious problem is the
dependence of the indices on mean reproductive success: skew values tend to be larger, as average numbers of offspring decrease,
due to random sampling error in numbers of offspring. Thus it is difficult to compare societies with different average lifetime
reproductive success using these indices, even though we have presented methods to calculate the expected reproductive skew
caused by random sampling error, especially when average numbers of offspring are small, as is often the case with cooperatively
breeding vertebrates. As an alternative, we propose using the spatial dispersion indices of population ecology (Morisita's
index or its standardized version) for the measurement of reproductive skew. These indices are almost independent of average
fecundity and have their own method of testing for random variation in offspring numbers.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献