全文获取类型
收费全文 | 656篇 |
免费 | 32篇 |
国内免费 | 2篇 |
专业分类
林业 | 87篇 |
农学 | 24篇 |
基础科学 | 1篇 |
62篇 | |
综合类 | 27篇 |
农作物 | 13篇 |
水产渔业 | 114篇 |
畜牧兽医 | 305篇 |
园艺 | 9篇 |
植物保护 | 48篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 19篇 |
2020年 | 10篇 |
2019年 | 11篇 |
2018年 | 20篇 |
2017年 | 18篇 |
2016年 | 12篇 |
2015年 | 31篇 |
2014年 | 21篇 |
2013年 | 37篇 |
2012年 | 35篇 |
2011年 | 53篇 |
2010年 | 26篇 |
2009年 | 29篇 |
2008年 | 47篇 |
2007年 | 47篇 |
2006年 | 54篇 |
2005年 | 48篇 |
2004年 | 28篇 |
2003年 | 32篇 |
2002年 | 26篇 |
2001年 | 17篇 |
2000年 | 14篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 7篇 |
1994年 | 1篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1972年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有690条查询结果,搜索用时 265 毫秒
1.
Mahmoud A. O. Dawood Shunsuke Koshio Manabu Ishikawa Mabrouk El-Sabagh Saichiro Yokoyama Wei-Long Wang Zhang Yukun Adissin Olivier 《Fish physiology and biochemistry》2017,43(1):179-192
Environmental stressors caused by inadequate aquaculture management strategies suppress the immune response of fish and make them more susceptible to diseases. Therefore, efforts have been made to relieve stress in fish by using various functional feed additives in the diet, including probiotics. The present work evaluates the effects of Lactobacillus rhamnosus (LR) on physiological stress response, blood chemistry and mucus secretion of red sea bream (Pagrus major) under low salinity stress. Fish were fed four diets supplemented with LR at [0 (LR0), 1 × 102 (LR1), 1 × 104 (LR2) and 1 × 106 (LR3) cells g?1] for 56 days. Before stress, blood cortisol, urea nitrogen (BUN) and total bilirubin (T-BIL) showed no significant difference (P > 0.05), whereas plasma glucose and triglyceride (TG) of fish-fed LR2 and LR3 diets were significantly lower (P < 0.05) than those of the other groups. Plasma total cholesterol (T-CHO) of fish-fed LR3 diet was significantly (P < 0.05) lower than that of the other groups. Furthermore, total plasma protein, mucus myeloperoxidase activity and the amount of mucus secretion were significantly enhanced in LR-supplemented groups when compared with the control group (P < 0.05). After the application of the low salinity stress test, plasma cortisol, glucose, T-CHO and TG contents in all groups showed an increased trend significantly (P < 0.01) compared to the fish before the stress challenge. However, plasma total protein and the amount of secreted mucus showed a decreased trend in all groups. On the other hand, BUN, T-BIL and mucus myeloperoxidase activity showed no significant difference after exposure to the low salinity stress (P > 0.05). In addition, the fish that received LR-supplemented diets showed significantly higher tolerance against low salinity stress than the fish-fed LR-free diet (P < 0.05). The physiological status and the detected immune responses, including total plasma protein and mucus myeloperoxidase activity in red sea bream, will provide a more comprehensive outlook of the effects of probiotics to relieve stress in fish. 相似文献
2.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers 下载免费PDF全文
Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献
3.
Saori MIURA Noriyuki HORIUCHI Kotaro MATSUMOTO Yoshiyasu KOBAYASHI Shin-ichiro KAWAZU Hisashi INOKUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):883-887
Monoclonal integration of bovine leukemia virus (BLV) proviral DNA into bovine genomes
was detected in peripheral blood from two clinical cases of enzootic bovine leukosis (EBL)
without enlargement of superficial lymph nodes. A BLV-specific probe hybridized with 1 to
3 EcoRI and HindIII fragments in these 2 atypical EBL
cattle by Southern blotting and hybridization, as well as in 3 typical EBL cattle. The
probe also hybridized to a large number of EcoRI and
HindIII fragments in 5 cattle with persistent leukosis. These results
suggest that the detection of monoclonal integration of BLV provirus into the host genome
may serve as a marker of monoclonal proliferation and malignancy in difficult to diagnose
EBL cattle. 相似文献
4.
Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease 下载免费PDF全文
T. Osuga K. Nakamura T. Morita S.Y. Lim K. Nisa N. Yokoyama N. Sasaki K. Morishita H. Ohta M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1518-1523
Background
In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.Objectives
To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.Animals
Forty‐three client‐owned dogs with CVHD.Methods
In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.Results
Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.Conclusions and Clinical Importance
These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD. 相似文献5.
Fumie MAGATA Yoshikazu ISHIDA Akio MIYAMOTO Hidefumi FURUOKA Hisashi INOKUMA Takashi SHIMIZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):81-84
We investigated the
concentration of the bacterial endotoxin lipopolysaccharide (LPS) in the blood, ovarian
follicular fluid and uterine fluid of a clinical case of bovine metritis. A 2-year-old
lactating Holstein cow exhibited continuous fever >39.5°C for more than 2 weeks after
normal calving. The cow produced a fetid, watery, red-brown uterine discharge from the
vagina and was diagnosed with metritis. The LPS concentrations in plasma and uterine fluid
were 0.94 and 6.34 endotoxin units (EU)/ml, respectively. One of seven
follicles showed an extremely high level of LPS (12.40 EU/ml) compared to
the other follicles (0.62–0.97 EU/ml). These results might suggest the
presence of high concentration of LPS in follicles in cows with postpartum metritis. 相似文献
6.
7.
8.
Md. Abdul Kader Shunsuke Koshio Manabu Ishikawa Saichiro Yokoyama Mahbuba Bulbul Yuki Honda Roger Edward Mamauag Asda Laining 《Fisheries Science》2011,77(1):119-128
A feeding trial was conducted to evaluate the effect of fermented soybean meal and scallop by-product blend (3:2) (FP) on
the performance of juvenile red sea bream. Five isocaloric diets were prepared by replacing 0% (FP0), 15% (FP15), 30% (FP30),
45% (FP45), and 60% (FP60) fishmeal (FM) protein with FP, respectively. Triplicate groups of fish (initial mean weight 2.83 g)
were fed the test diets for 45 days in a flowthrough seawater system. The results demonstrated that growth rates of fish fed
FP0, FP15, and FP30 were similar, and significantly higher (P < 0.05) than those of FP45 and FP60. Nutrient utilization was significantly lower in FP60, with no differences found among
the other groups. Dietary heavy-metal contents were affected by inclusion of FP, impacting on whole-body heavy-metal contents.
In terms of oxidative stress, fish fed the FP30 diet were in the best condition, since this fish group showed the least oxidative-stressed
condition as well as the highest tolerance against oxidation. In conclusion, the approach of utilizing this fermented mixture
is promising and it could replace at least 30% FM protein in red sea bream diet without negative effects on performance, body
composition or health of fish. 相似文献
9.
Zhi-Shan Lin Zhi-Fu Cui Xiang-Yan Zeng You-Zhi Ma Zeng-Yan Zhang Toshiki Nakamura Goro Ishikawa Kazuhiro Nakamura Hisashi Yoshida Zhi-Yong Xin 《Euphytica》2007,158(1-2):109-118
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that
line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452
were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was
a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain
terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably
2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. 相似文献
10.
Michito Tsuyama Hajime Kobayashi Masaru Shinya Hisashi Yahata Yoshichika Kobayashi 《Journal of Forest Research》1996,1(2):79-85
Using attached and detached leaves ofAcer palmatum Thunb. andRhaphiolepsis umbellata Makino, pulse-modulated chlorophyll fluorescence and CO2 exchange were measured. Quantum yield of photosynthesis was determined from the fluorescence parameter(Fm′−Fs)/Fm′, where (Fm′−Fs) was defined as the difference between steady state chlorophyll fluorescence (Fs) and maximum fluorescence (Fm′) elicited by a saturating light pulse. The rate of electron transport through photosystem II (total electron flow) was calculated
from the product of quantum yield andA (PFD), whereA is the rate of absorbed photons as given by leaf absorptance, and PFD is the photon flux density at the leaf surface. The
rate of electron transport dependant on CO2 uptake (assimilative electron flow) was calculated from the gross photosynthetic rate in a leaf. The difference between the
rates of total and assimilative electron transport was denoted as the rate of non-assimilative electron transport which depends
on photorespiration and oxygen reduction. Available data provided quantitative information on the rate of non-assimilative
electron flow in intact leaves. When leaf photosynthesis ofA. palmatum was measured under sunlight, the rates of total and assimilative electron transport were determined to be approximately 900
and 150 μmol equiv. e/mg Chl·h, respectively. The difference (750 μmol equiv. e/mg Chl·h) was attributed to the activity of
non-assimilative electron flow. The ratio of total to assimilative electron flow was found to increase gradually with rising
in irradiance. The results suggest that non-assimilative electron flow occurred at much higher rate than assimilative electron
flow at high irradiance. Implications of the results are briefly discussed in relation to photosynthesis limitation in tree
leaves. 相似文献