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排序方式: 共有902条查询结果,搜索用时 15 毫秒
891.
Kusuda S Nagami H Kusunoki H Nishikaku T Nakagawa D Takida T Kurita D Uemichi K Fukai M Kubota H Ueda K Ooe T Okuda K Ueda K Doi O 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1093-1095
The serum and fecal testosterone (T) concentrations and testicular sizes of two male bharals (Pseudois nayaur) were determined for approximately one year. The profiles of the fecal T concentrations showed a similar tendency as the profiles of serum T concentrations, and there was a significant correlation between serum and fecal T concentrations (r=0.72). T concentrations rose drastically in October and decreased gradually until January. The maximum testicular size was observed between November and January. Semen collected between December and January was excellent in quality and comparable to domestic sheep and goats. The active periods of the testes were synchronized with the early breeding season of females. 相似文献
892.
Mortality processes of hatchery‐reared Pacific bluefin tuna Thunnus orientalis (Temminck et Schlegel) larvae in relation to their piscivory 下载免费PDF全文
Yosuke Tanaka Kazunori Kumon Yuka Ishihi Takeshi Eba Akefumi Nishi Hideki Nikaido Satoshi Shiozawa 《Aquaculture Research》2018,49(1):11-18
In mass culture of Pacific bluefin tuna Thunnus orientalis, yolk‐sac larvae of other species are fed as a major prey item to tuna larvae from 7 to 8 mm in total length. Marked growth variations in tuna larvae are frequently observed after feeding of yolk‐sac larvae, and this variation in the growth of tuna larvae is subsequently a factor leading to the prevalence of cannibalistic attacks. To elucidate details of the mortality process of hatchery‐reared tuna larvae after the initiation of yolk‐sac larvae feeding, we compared the nutritional and growth histories of the surviving (live) tuna larvae to those of the dead fish, found dead on the bottom of the tank, as direct evidence of their mortality processes. Cause of mortality of tuna larvae 3 and 5 days after the initiation of feeding of yolk‐sac larvae was assessed from nitrogen stable isotope and otolith microstructure analyses. Stable isotope analysis revealed that the live fish rapidly utilized prey fish larvae, but the dead fish had depended more on rotifers relative to the live fish 3 and 5 days after the initiation of feeding of yolk‐sac larvae. The growth histories based on otolith increments were compared between the live and dead tuna larvae and indicated that the live fish showed significantly faster growth histories than dead fish. Our results suggest that fast‐growing larvae at the onset of piscivory could survive in the mass culture tank of Pacific bluefin tuna and were characterized by growth‐selective mortality. 相似文献
893.
Kitao M Tobita H Utsugi H Komatsu M Kitaoka S Maruyama Y Koike T 《Tree physiology》2012,32(8):998-1007
To assess the effects of elevated CO(2) concentration ([CO(2)]) on the photosynthetic properties around spring budbreak, we monitored the total leaf sugar and starch content, and chlorophyll fluorescence in 1-year-old needles of Sakhalin spruce (Picea glehnii Masters) seedlings in relation to the timing of budbreak, grown in a phytotron under natural daylight at two [CO(2)] levels (ambient: 360?μmol mol(-1) and elevated: 720?μmol mol(-1)). Budbreak was accelerated by elevated [CO(2)] accompanied with earlier temporal declines in the quantum yield of PSII electron transport (Φ(PSII)) and photochemical quenching (q(L)). Plants grown under elevated [CO(2)] showed pre-budbreak leaf starch content twice as high with no significant difference in Φ(PSII) from ambient-CO(2)-grown plants when compared at the same measurement [CO(2)], i.e., 360 or 720?μmol mol(-1), suggesting that the enhanced pre-budbreak leaf starch accumulation might not cause down-regulation of photosynthesis in pre-existing needles under elevated [CO(2)]. Conversely, lower excitation pressure adjusted for the efficiency of PSII photochemistry ((1?-?q(P)) F(v)'/F(m)') was observed in plants grown under elevated [CO(2)] around budbreak when compared at their growth [CO(2)] (i.e., comparing (1?-?q(P)) F(v)'/F(m)' measured at 720?μmol mol(-1) in elevated-CO(2)-grown plants with that at 360?μmol mol(-1) in ambient-CO(2)-grown plants), which suggests lower rate of photoinactivation of PSII in the elevated-CO(2)-grown plants around spring budbreak. The degree of photoinhibition, as indicated by the overnight-dark-adapted F(v)/F(m), however, showed no difference between CO(2) treatments, thereby suggesting that photoprotection during the daytime or the repair of PSII at night was sufficient to alleviate differences in the rate of photoinactivation. 相似文献
894.
Tomoyasu Nishizawa Aihua Quan Ayaaki Kai Kanako Tago Satoshi Ishii Weishou Shen Kazuo Isobe Shigeto Otsuka Keishi Senoo 《Biology and Fertility of Soils》2014,50(6):1001-1007
Pelleted poultry manure is recommended for use with agricultural soil as a replacement for chemical fertilizers; however, application of the manure stimulates nitrous oxide (N2O) emission from the soil through denitrification. To mitigate the N2O emission caused by application of pelleted poultry manure, soil microcosms were set up; each microcosm was inoculated with one of the following N2-generating denitrifier strains previously been isolated from paddy soil: Azoarcus, Dyella, Dechloromonas, Niastella, and Burkholderia. When pelleted poultry manure was incubated on its own, N2O was produced by denitrification. In contrast, N2O emission was significantly lowered when the manure was inoculated with most of the N2-generating strains. In soil microcosms, N2O was emitted during incubation after application of the pelleted manure, while N2O flux was significantly lowered when the soil was inoculated with Azoarcus sp. KS11B, Niastella sp. KS31B, or Burkholderia sp. TSO47-3 on the 12th day of incubation. In addition, when pelleted manure was inoculated with the strains prior to application in the soil microcosms, the level of N2O emission was significantly lowered to ca. 40–60 % that from the non-inoculated control. Our study provides the prototype of a technique that uses microbial technology to mitigate N2O emission from agricultural soil fertilized with pelleted poultry manure. 相似文献
895.
Mineo?OkamotoEmail author Satoshi?Nojima Yasuo?Furushima William?C.?Phoel 《Fisheries Science》2005,71(2):263-270
Coral larvae, produced from a mass spawning event, were successfully settled on special stone settlement sticks and raised
in situ for eventual transport to other reefs. The test area, Sekisei lagoon, Okinawa Prefecture, Japan, is located close to the
warm Kuroshio current and is surmised to be the source from which major Japanese corals are derived. A total of 131 settlement
sticks, with small holes in their sides to increase protection from grazing (4 mm in diameter and approximately 5 mm deep),
were deployed in the lagoon the day before the coral’s mass spawning. After 3 months, 61 sticks were recovered containing
71 corals, mostly in the holes. After 1 year, three corals were confirmed to be growing well and extending outside the holes
of the three sticks out of 70 sticks left in the water at the lagoon site. They survived two potentially lethal conditions,
that is, high water temperatures with associated extensive coral bleaching and continuous grazing pressure from predators.
This procedure is applicable for large-scale coral transplantation, not only in Japan but also in other tropical countries. 相似文献
896.
Kobayashi S Murakami K Sasaki S Okubo H Hirota N Notsu A Fukui M Date C 《Public health nutrition》2011,14(7):1200-1211
897.
Takayuki Takebe Takeo Kurihara Nobuaki Suzuki Kentaro Ide Hideki Nikaido Yosuke Tanaka Satoshi Shiozawa Hitoshi Imaizumi Shukei Masuma Yoshitaka Sakakura 《Fisheries Science》2012,78(2):343-350
We conducted a rearing experiment on Pacific bluefin tuna (PBT) larvae, which originated from one female broodstock, and determined
the growth history of the larvae to clarify when the growth difference occurs. We investigated the otolith microstructure
of the PBT larvae to examine the individual growth history and to predict the age and body size at the onset of individual
growth difference. Since total length (TL) of fish can be back-calculated from otolith radius, we back-calculated TLs of 100
fish of 19 days post hatch (dph) divided into three size groups (small, intermediate, large). Growth difference was recognized
from 3 dph (mouth opening), and the difference became larger thereafter. Growth of large-size fish was assumed to be promoted
by the feeding conditions of PBT larvae. 相似文献
898.
Isolation of microsatellite markers by in silico screening implicated for genetic linkage mapping in Japanese pufferfish Takifugu rubripes 总被引:1,自引:0,他引:1
Satoshi FURUKAWA Hirohiko TAKESHIMA Taro OTAKA Toru MITSUBOSHI Kunio SHIRASU Daisuke IKEDA Gen KANEKO Mutsumi NISHIDA Shugo WATABE 《Fisheries Science》2004,70(4):620-628
ABSTRACT: The search for dinucleotide repeat microsatellites within scaffolds 1–25 of genome database JGI Fugu v3.0 for the pufferfish Takifugu rubripes revealed that 80% of microsatellite loci consisted of five to 13-fold repeats with locus-specific differences in density. Eleven out of 15 microsatellite loci isolated from the database with which genotyping using wild pufferfish was successfully performed showed polymorphism; that is, the means of the number of alleles and expected and observed heterozygosities at these 11 loci were 21.8, 0.915 and 0.829, respectively. It was confirmed that eight out of the 11 polymorphic loci were inherited through the Mendelian law and one pair of microsatellite loci derived from the same scaffold was linked. These results demonstrated that these loci are useful for constructing a linkage map in the pufferfish as DNA markers. 相似文献
899.
Tom ICHINOHE Nobuo KANNO Yasuji HARADA Takuya YOGO Masahiro TAGAWA Satoshi SOETA Hajime AMASAKI Yasushi HARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):761-770
Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by
degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the
progression of chondroid metaplasia and the changes in the expression of ECM components in
canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal
CCLs from 12 young beagles (control group) were examined histologically and
immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen
(COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs were
quantified using hematoxylin–eosin staining. The percentage of round cells was higher in
the CCLR group than in controls. COLI-positive areas were seen extensively in the
connecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLR
group, there were fewer COLI-positive areas, but many COLI-positive cells. The percentages
of COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls.
The number of spindle cells with perinuclear halo was high in the CCLR group, and most of
these cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments,
decreased with increased COLIII expression in degenerated CCL tissue, which shows that the
deposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased,
which may contribute to the synthesis of cartilage matrix. The expression of COLII and
SOX9 in ligamentocytes showed that these cells tend to differentiate into
chondrocytes. 相似文献