全文获取类型
收费全文 | 720篇 |
免费 | 19篇 |
国内免费 | 9篇 |
专业分类
林业 | 43篇 |
农学 | 28篇 |
基础科学 | 1篇 |
130篇 | |
综合类 | 45篇 |
农作物 | 23篇 |
水产渔业 | 87篇 |
畜牧兽医 | 337篇 |
园艺 | 5篇 |
植物保护 | 49篇 |
出版年
2022年 | 9篇 |
2021年 | 17篇 |
2020年 | 9篇 |
2019年 | 11篇 |
2018年 | 9篇 |
2017年 | 13篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 23篇 |
2013年 | 70篇 |
2012年 | 25篇 |
2011年 | 23篇 |
2010年 | 19篇 |
2009年 | 24篇 |
2008年 | 36篇 |
2007年 | 42篇 |
2006年 | 44篇 |
2005年 | 36篇 |
2004年 | 40篇 |
2003年 | 45篇 |
2002年 | 41篇 |
2001年 | 36篇 |
2000年 | 33篇 |
1999年 | 27篇 |
1998年 | 5篇 |
1997年 | 8篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1992年 | 3篇 |
1991年 | 8篇 |
1990年 | 8篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1983年 | 5篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1968年 | 2篇 |
1962年 | 1篇 |
1960年 | 3篇 |
1957年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有748条查询结果,搜索用时 15 毫秒
741.
Masahiro Horinouchi Prasert Tongnunui Keisuke Furumitsu Yohei Nakamura Kouki Kanou Atsuko Yamaguchi Ken Okamoto Mitsuhiko Sano 《Fisheries Science》2012,78(3):577-587
To clarify the feeding habits of seagrass fishes, we examined the gut contents from 42 fish species collected in seagrass
habitats in Trang. Thirteen species showed ontogenetic and/or seasonal changes in food-use patterns. Smaller individuals generally
preyed on small planktonic items (e.g., copepod larvae) or small benthic/epiphytic crustaceans (e.g., harpacticoid copepods),
with subsequent changes to other prey items (e.g., shrimps, crabs, detritus and filamentous algae) with growth. The most important
dietary items for the seagrass fish assemblages comprised benthic/epiphytic crustaceans, detritus, and planktonic copepods.
Cluster analysis based on dietary overlaps showed that the seagrass fishes comprised eight feeding guilds (large benthic/epiphytic
crustacean, detritus, planktonic animal, small benthic/epiphytic crustacean, mollusc, invertebrate egg, polychaete, and fish
feeders). Of these, the first three guilds were the most abundantly represented, whereas the last three were each represented
by only a single species. 相似文献
742.
Recruitment and movement of the hard clam Meretrix lusoria in a tidal river of northern Kyushu,Japan
Yasuhisa Henmi Satoshi Kobayashi Junpei Yamaguchi Masahiro Hashiguchi 《Fisheries Science》2014,80(4):705-714
Size-frequency distributions of Meretrix lusoria, a commercially important bivalve in Japan, were compared among 6 sites in tidal flats of a small river in Kafuri Bay, northern Kyushu, Japan during 2006–2008. In Kafuri Bay, the hard clam resource is strictly managed and mean biomass of this species on the fishing ground (about 1.5 km2) exceeded 1.5 kg m?2 in 2008. Small clams (<5 mm in shell length, SL) were most abundant in the border area between the river and the sea, while large clams (>40 mm SL) were rare there. In contrast, in the lower site of the marine area (site L), most clams were >30 mm SL. These results indicate that small clams move from riverine to marine areas with growth (post-settlement movement). Year-round, very small clams (<1 mm SL) were present and clams that were 2–5 mm SL were very rare, although the spawning season is thought to occur in summer. Probably, the early growth of many new recruits is very slow and most may even be <1 mm SL in the next spring, although some clams grow to >5 mm SL in a short period of time. 相似文献
743.
Yuya Shigematsu Yuichiro Ochi Shuhei Yamaguchi Kazumitsu Nakaguchi Yoichi Sakai Jun-ya Shibata Wataru Nishijima Takeshi Tomiyama 《Fisheries Science》2017,83(3):373-382
This study revealed the spatial variation in abundance and body size of larval fishes in the Seto Inland Sea, Japan, in January 2014 and 2015. Fish larvae were collected by a 1.3-m-diameter ring net towed at the surface and at 10-m depth at 21 stations. The most dominant species was the sandlance Ammodytes japonicus, constituting 82% of total larval fish caught. The body size of A. japonicus was greater [ca. 9 mm total length (TL) in 2014] in eastern areas than in western areas (ca. 5 mm TL in 2014). This trend was also observed in rockfishes (Sebastiscus marmoratus and Sebastes inermis species complex), suggesting a common phenomenon in this region. Because the water temperature was lower in eastern areas, it is likely that the longitudinal differences in larval body size are attributable to earlier spawning in eastern areas caused by different temperature conditions. 相似文献
744.
Tetsuro Shiraishi Suvarna D Ketkar Hajime Kitano Mitsuo Nyuji Akihiko Yamaguchi Michiya Matsuyama 《Fisheries Science》2008,74(4):764-769
Abstract: The question of whether the ovulation and spawning time in chub mackerel Scomber japonicus is entrained by a circadian rhythm was raised by our previous experiments. Further questions were also raised about whether the time course of human chorionic gonadotropin (hCG)-induced final oocyte maturation (FOM) and ovulation reflected the natural time course induced by endogeneous pituitary gonadotropin (GtH). To address these questions, hCG and gonadotropin-releasing hormone analog (GnRHa) were administered at two 'opposite' times, 14:00 and 02:00 hours, and the time courses of FOM and ovulation were compared. When hCG was injected, ovulation occurred 33 h post-injection in both groups, regardless of the timing of the hCG injection. The timing of ovulation in chub mackerel depends on the timing of hCG injection, but apparently not on circadian rhythms. When GnRHa was injected, ovulation began at 36 h post-injection of GnRHa, regardless of the timing of injection. These results indicate that the time course of FOM and ovulation in the chub mackerel followed a similar pattern whether stimulated by hCG injection or spontaneous luteinizing hormone (LH) surge because GnRHa induces the secretion of endogenous GtH (primarily LH) from the fish pituitary. Thus, it is concluded that the time course of hCG-induced FOM and ovulation in chub mackerel follows the natural time course induced by endogenous pituitary LH. 相似文献
745.
N. Kumakura K. Okuzawa S. Yamaguchi K. Gen B.S. Lim H. Kagawa 《Fish physiology and biochemistry》2003,28(1-4):99-100
We examined the effects of gonadotropin-releasing hormone agonist (GnRHa) and testosterone (T) on the level of gonadotropin subunit mRNAs in the pituitary of ovariectomized or intact female red seabream. Ovariectomy induced increase of seabream (sb) GnRH, glycoprotein (GP) α and luteinizing hormone (LH) β mRNA levels. GnRHa treatment also stimulated GPα and LHβ mRNA levels. T treatment reduced GPα and LHβ mRNA expression probably via negative feedback action on sbGnRH. Both GnRHa and T treatment had no effect on follicle-stimulating hormone (FSH) β mRNA levels. These results suggest that the regulatory mechanisms of GPα and LHβ gene expression differ from those of FSHβ gene. 相似文献
746.
Valentin Eckart Takuya Yamaguchi Kati Franzke Sven M. Bergmann Pierre Boudinot Edwige Quillet Motokazu Kawanobe Neila Alvarez de Haro Uwe Fischer 《Journal of fish diseases》2019,42(2):181-187
The production of piscine viruses, in particular of koi herpesvirus (KHV, CyHV‐3) and infectious salmon anaemia virus (ISAV), is still challenging due to the limited susceptibility of available cell lines to these viruses. A number of cell lines from different fish species were compared to standard diagnostic cell lines for KHV and ISAV regarding their capability to exhibit a cytopathic effect (CPE) and to accumulate virus. Two cell lines, so far undescribed, appeared to be useful for diagnostic purposes. Fr994, a cell line derived from ovaries of rainbow trout (Oncorhynchus mykiss), produced constantly high ISA virus (ISAV) titres and developed a pronounced CPE even at high cell passage numbers, while standard cell lines are reported to gradually loose these properties upon propagation. Another cell line isolated from the head kidney of common carp (Cyprinus carpio), KoK, showed a KHV induced CPE earlier than the standard cell line used for diagnostics. A third cell line, named Fin‐4, established from the fin epithelium of rainbow trout did not promote efficient replication of tested viruses, but showed antigen sampling properties and might be useful as an in vitro model for virus uptake or phagocytosis. 相似文献
747.
Otake Tsuguo Amano Yosuke Shirai Kotaro Mochioka Noritaka Takahashi Toshiro Chow Seinen Kurogi Hiroaki Dou Shouzeng Yamaguchi Asuka Tsukamoto Katsumi 《Fisheries Science》2019,85(3):483-493
Fisheries Science - The widely distributed East Asian Japanese eel Anguilla japonica constitutes a single genetically homogeneous population with a single spawning area near the West Mariana Ridge.... 相似文献
748.
C. Kiribuchi-Otobe T. Nagamine T. Yanagisawa M. Ohnishi I. Yamaguchi 《Cereal Chemistry》1997,74(1):72-74
In our wheat breeding program to introduce the low amylose character of Tanikei A6099 to elite lines, five waxy lines were unexpectedly obtained from 249 doubled haploid lines of the F1 hybrid of Saikai 168 × Tanikei A6099. The amylose content of all the waxy lines was <1% and the blue value was <0.1. Starch granule-bound proteins were extracted and subjected to modified sodium dodecyl sulfate polyacrylamide gel electrophoresis. The waxy lines lacked the Wx protein. Starch paste viscosity measurements gave pasting profiles of waxy wheat starch that were quite different from those of nonwaxy wheats but similar to those of waxy maize. However, the peak viscosity of waxy wheats was much higher than that of the waxy maize. 相似文献