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301.
Eric Gilman Jeff Gearhart Blake Price Scott Eckert Henry Milliken John Wang Yonat Swimmer Daisuke Shiode Osamu Abe S. Hoyt Peckham Milani Chaloupka Martin Hall Jeff Mangel Joanna Alfaro-Shigueto Paul Dalzell & Asuka Ishizaki 《Fish and Fisheries》2010,11(1):57-88
There is growing evidence that small-scale, coastal, passive net fisheries may be the largest single threat to some sea turtle populations. We review assessments of turtle interactions in these fisheries, and experiments on gear-technology approaches (modifying gear designs, materials and fishing methods) to mitigate turtle by-catch, available from a small number of studies and fisheries. Additional assessments are needed to improve the limited understanding of the relative degree of risk coastal net fisheries pose to turtle populations, to prioritize limited conservation resources and identify suitable mitigation opportunities. Whether gear technology provides effective and commercially viable solutions, alone or in combination with other approaches, is not well-understood. Fishery-specific assessments and trials are needed, as differences between fisheries, including in gear designs; turtle and target species, sizes and abundance; socioeconomic context; and practicality affect efficacy and suitability of by-catch mitigation methods. Promising gear-technology approaches for gillnets and trammel nets include: increasing gear visibility to turtles but not target species, through illumination and line materials; reducing net vertical height; increasing tiedown length or eliminating tiedowns; incorporating shark-shaped silhouettes; and modifying float characteristics, the number of floats or eliminating floats. Promising gear-technology approaches for pound nets and other trap gear include: replacing mesh with ropes in the upper portion of leaders; incorporating a turtle releasing device into traps; modifying the shape of the trap roof to direct turtles towards the location of an escapement device; using an open trap; and incorporating a device to prevent sea turtle entrance into traps. 相似文献
302.
Kojima Hajime Kohgo Yuji Shimada Kiyoshi Shoda Daisuke Suzuki Hisato Saito Hirotaka 《Paddy and Water Environment》2020,18(2):431-442
Paddy and Water Environment - The 2011 Tohoku earthquake damaged many small earthen dams in Japan, causing flood damage and human casualties. Since then, the necessity for developing accurate... 相似文献
303.
Shunji Kurokawa Akito Kaga Mai Tsuda Daisuke Sekine Tomoko Shibuya 《Weed Biology and Management》2019,19(3):103-110
A canopy height‐to‐row spacing ratio (CHRSR) of 1.0 is expected to be a simple and practical onsite index for soybean growers to determine when further weed control is no longer necessary. This is decided when relative photosynthetic photon flux density (PPFD) reaches 50% under the soybean canopy. To evaluate the validity of this index, a 2‐year field experiment was conducted to compare days after sowing (DAS) to reach a relative PPFD of 50% (defined as PPFD50) and DAS to reach a CHRSR of 1.0 (defined as CHRSR1.0) in 190 accessions with different canopy architectures from a soybean core collection. A total of 104 accessions, for which final relative PPFD reached <10% in 2014, were examined for the differences between CHRSR1.0 and PPFD50. The mean and median values of the difference in 2014 were 0.02 and 2.2, respectively. Similarly, the mean and median values in 2015 were 2.8 and 2.6, respectively. Thus, CHRSR1.0 tended to be achieved slightly later than PPFD50, so a consideration was made that there would be a negligible risk of failure if growers used CHRSR1.0 to determine the termination time for weed control in the most of accessions. Although there were some accessions with a standing type of morphological characteristics or with a smaller or narrower leaf, showing negative differences between CHRSR1.0 and PPFD50 larger than 1 week, a CHRSR of 1.0 could be used to estimate PPFD50 in most of accessions without risk of failure to control weeds. 相似文献
304.
Megumi ITOH Yasuhiro NAKAJIMA Kouki KUWANO Daisuke MAEDA Yoshie SAKURAI Yoshitaka MATSUI Satoshi KAWAMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):193
We previously reported the possibility of using the electrocardiogram variable to estimate blood calcium (Ca) concentration in dairy cows based on the strong positive correlation between the blood Ca concentration and the inverse of the corrected ST peak interval (STc−1). To improve the accuracy of the estimation of blood Ca concentration, we investigated the relationship between blood Ca concentration and STc−1 for each postpartum day and available variables other than STc−1. We measured multiple variables (milk yield, calving number, age, body temperature, etc.), including serum total Ca concentration (tCa), blood ionized Ca concentration (iCa) and STc−1 in 462 Holstein cows on days 0, 1, 2, 3, 5, and 7 postpartum. A very high correlation was observed between iCa and tCa. The association between tCa and STc−1 for each postpartum day had a high coefficient of determination of 0.61–0.79 postpartum 0–2 days but decreased after the third day. In the investigation using the data from postpartum days 0–2, STc−1, heart rate interval, calving number, and age were highly correlated with tCa. In addition, a multiple regression equation was obtained with tCa as the objective variable and STc−1 and calving number as explanatory variables. The estimation accuracy was improved as compared with the simple regression equation using only STc−1 as the explanatory variable. This multiple regression equation was used for 11 cows suspected of having hypocalcemia, and it was able to correctly detect cows requiring early treatment, except for one cow. 相似文献
305.
Daisuke TAKAMATSU Masumi SATO Mikio YOSHIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):29-34
Melissococcus plutonius is an important pathogen that causes
European foulbrood (EFB) in honeybee larvae. Recently, we discovered a group of M.
plutonius strains that are phenotypically and genetically distinct from other
strains. These strains belong to clonal complex (CC) 12, as determined by multilocus
sequence typing analysis, and show atypical cultural and biochemical characteristics
in vitro compared with strains of other CCs tested. Although EFB is
considered to be a purely intestinal infection according to early studies, it is unknown
whether the recently found CC12 strains cause EFB by the same pathomechanism. In this
study, to obtain a better understanding of EFB, we infected European honeybee
(Apis mellifera) larvae per os with a
well-characterized CC12 strain, DAT561, and analyzed the larvae histopathologically.
Ingested DAT561 was mainly localized in the midgut lumen surrounded by the peritrophic
matrix (PM) in the larvae. In badly affected larvae, the PM and midgut epithelial cells
degenerated, and some bacterial cells were detected outside of the midgut. However, they
did not proliferate in the deep tissues actively. By immunohistochemical analysis, the PM
was stained with anti-M. plutonius serum in most of the DAT561-infected
larvae. In some larvae, luminal surfaces of the PM were more strongly stained than the
inside. These results suggest that infection of CC12 strain in honeybee larvae is
essentially confined to the intestine. Moreover, our results imply the presence of
M. plutonius-derived substances diffusing into the larval tissues in
the course of infection. 相似文献
306.
David Roy Jean-Philippe Auger Mariela Segura Nahuel Fittipaldi Daisuke Takamatsu Masatoshi Okura Marcelo Gottschalk 《Canadian journal of veterinary research》2015,79(2):141-146
Streptococcus suis is an important swine pathogen and a zoonotic agent causing meningitis and septicemia. Although serotype 2 is the most virulent type, serotype 14 is emerging, and understanding of its pathogenesis is limited. To study the role of the capsular polysaccharide (CPS) of serotype 14 as a virulence factor, we constructed knockout mutants devoid of either cps14B, a highly conserved regulatory gene, or neu14C, a gene coding for uridine diphospho-N-acetylglucosamine 2-epimerase, which is involved in sialic acid synthesis. The mutants showed total loss of the CPS with coagglutination assays and electron microscopy. Phagocytosis assays showed high susceptibility of mutant Δcps14B. An in vivo murine model was used to demonstrate attenuated virulence of this non-encapsulated mutant. Despite the difference in the CPS composition of different serotypes, this study has demonstrated for the first time that the CPS of a serotype other than 2 is also an important antiphagocytic factor and a critical virulence factor. 相似文献
307.
Chiyo KITAYAMA Motoki SASAKI Hajime ISHIKAWA Toshihiro MOGOE Seiji OHSUMI Yutaka FUKUI Teguh BUDIPITOJO Daisuke KONDOH Nobuo KITAMURA 《The Journal of reproduction and development》2015,61(5):415-421
The structure and functions of placentas were examined in 3 species of rorqual whales, common minke (Balaenoptera acutorostrata), Bryde’s (B. brydei) and sei (B. borealis) whales, with the aim of confirming the structural characteristics of the chorion, including the presence of the areolar part, and clarifying steroidogenic activities and fetomaternal interactions in the placentas of these whales. Placentas were collected from the second phase of the Japanese Whale Research Program under Special Permit in the North Pacific (JARPN II). Histological and ultrastructural examinations revealed that these whale placentas were epitheliochorial placentas with the interdigitation of chorionic villi lined by monolayer uninucleate cells (trophoblast cells) and endometrial crypts as well as folded placentation by fold-like chorionic villi. Moreover, well-developed pouch-like areolae were observed in the placentas, and active
absorption was suggested in the chorionic epithelial cells of the areolar part (areolar trophoblast cells). Berlin blue staining showed the presence of ferric ions (Fe3+) in the uterine glandular epithelial cells and within the stroma of chorionic villi in the areolar part. An immunohistochemical examination revealed tartrate-resistant acid phosphatase (TRAP; known as uteroferrin in uteri) in the cytoplasm of glandular cells and areolar trophoblast cells. This result suggested that, in cetaceans, uteroferrin is used to supply iron to the fetus. Furthermore, immunoreactivity for P450scc and P450arom was detected in trophoblast cells, but not in areolar trophoblast cells, suggesting that trophoblast cells synthesize estrogen in whale placentas. Therefore, we herein immunohistochemically revealed the localization of aromatase and uteroferrin in cetacean placentas during pregnancy for the first time. 相似文献
308.
Masahiko YASUDA Takashi INOUE Masami UENO Hanako MORITA Nobuhito HAYASHIMOTO Kenji KAWAI Toshio ITOH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1673-1676
The common marmoset is widely used in neuroscience and regenerative medicine research.
However, information concerning common marmoset disorders, particularly infectious
diseases, is scarce. Here, we report a case of a female common marmoset that died suddenly
due to gas gangrene. The animal presented with gaseous abdominal distention at postmortem,
and Clostridium perfringens type A was isolated from several tissues.
Vacuoles, a Gram-positive bacteremia and intravascular hemolysis were observed
microscopically in the muscles, liver and lungs. On the basis of these findings, we
diagnosed nontraumatic gas gangrene caused by Clostridium perfringens
type A in this common marmoset. 相似文献
309.
Toshiho Nishita Yuichiro Tomita Daisuke Yorifuji Kensuke Orito Hideharu Ochiai Kazuyosi Arishima 《Acta veterinaria Scandinavica》2011,53(1):63
Background
The developmental profile of chicken carbonic anhydrase-III (CA-III) blood levels has not been previously determined or reported. We isolated CA-III from chicken muscle and investigated age-related changes in the levels of CA-III in blood.Methods
CA-III was purified from chicken muscle. The levels of CA-III in plasma and erythrocytes from 278 female chickens (aged 1-93 weeks) and 68 male chickens (aged 3-59 weeks) were determined by ELISA.Results
The mean level of CA-III in female chicken erythrocytes (1 week old) was 4.6 μg/g of Hb, and the CA-III level did not change until 16 weeks of age. The level then increased until 63 weeks of age (11.8 μg/g of Hb), decreased to 4.7 μg/g of Hb at 73 weeks of age, and increased again until 93 weeks of age (8.6 μg/g of Hb). The mean level of CA-III in erythrocytes from male chickens (3 weeks old) was 2.4 μg/g of Hb, and this level remained steady until 59 weeks of age. The mean plasma level of CA-III in 1-week-old female chickens was 60 ng/mL, and this level was increased at 3 weeks of age (141 ng/mL) and then remained steady until 80 weeks of age (122 ng/mL). The mean plasma level of CA-III in 3-week-old male chickens was 58 ng/mL, and this level remained steady until 59 weeks of age.Conclusion
We observed both developmental changes and sex differences in CA-III concentrations in White Leghorn (WL) chicken erythrocytes and plasma. Simple linear regression analysis showed a significant association between the erythrocyte CA-III level and egg-laying rate in WL-chickens 16-63 weeks of age (p < 0.01). 相似文献310.
Kondoh D Nashimoto M Kanayama S Nakamuta N Taniguchi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(8):1007-1014
Although it has been commonly believed that birds are more dependent on the vision and audition than the olfaction, recent studies indicate that the olfaction of birds is related to the reproductive, homing, and predatory behaviors. In an attempt to reveal the dependence on the olfactory system in crows, we examined the olfactory system of the Japanese jungle crow (Corvus macrorhynchos) by histological, ultrastructural, and lectin histochemical methods. The olfactory epithelium (OE) of the crow occupied remarkably a small area of the nasal cavity (NC) and had the histological and ultrastructural features like other birds. The olfactory bulb (OB) of the crow was remarkably small and did not possess the olfactory ventricle. The left and right halves of the OB were fused in many cases. In the lectin histochemistry, soybean agglutinin (SBA) and Vicia villosa agglutinin (VVA) stained a small number of the receptor cells (RCs) in the OE and the olfactory nerve layer (ONL) and glomerular layer (GL) on the dorsocaudal region of the OB. Phaseolus vulgaris agglutinin-E (PHA-E) stained several RCs in the OE and the ONL and GL on the ventral region of the OB. These results suggest that 1) the crow has less-developed olfactory system than other birds, and 2) the dedicated olfactory receptor cells project their axons to the specific regions of the OB in the crow. 相似文献