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71.
72.
Nguyen Viet LINH Kazuhiro KIKUCHI Michiko NAKAI Fuminori TANIHARA Junko NOGUCHI Hiroyuki KANEKO Thanh Quang DANG-NGUYEN Nguyen Thi MEN Nguyen VAN HANH Tamas SOMFAI Bui Xuan NGUYEN Takashi NAGAI Noboru MANABE 《The Journal of reproduction and development》2013,59(6):549-556
Mitochondria are reported to be critical in in vitro maturation of
oocytes and subsequent embryo development after fertilization, but their contribution
for fertilization has not been investigated in detail. In the present study, we
investigate the contribution of mitochondria to fertilization using reconstructed
porcine oocytes by fusion of ooplasmic fragments produced by serial centrifugations
(centri-fusion). Firstly, we evaluated the characteristics of ooplasmic fragments.
Three types of fragments were obtained by centrifugation of porcine oocytes matured
in vitro for 46 h: brownish (B), transparent (T) and large (L)
fragments containing both B and T parts in a fragment. The production efficiencies of
these types of fragments were 71.7, 91.0 and 17.8 fragments/100 oocytes,
respectively. In experiments, L fragments were excluded because they contained both
brownish and transparent components that were apparently intermediate between B and T
fragments. Observations by confocal microscopy after staining with MitoTracker Red
CMXRos® and transmission electron microscopy revealed highly condensed
active mitochondria in B fragments in contrast to T fragments that contained only
sparse organelles. We reconstructed oocytes by fusion of a karyoplast and two
cytoplasts from B and T fragments (B and T oocytes, respectively). The B oocytes
showed higher sperm penetration (95.8%) and male pronuclear formation rates (94.2%)
by in vitro fertilization than T oocytes (66.7% and 50.0%,
respectively). These results suggest that the active mitochondria in oocytes may be
related to their ability for fertilization. 相似文献
73.
Aramid fibers are mainly used for industrial applications and human body protection against ballistic threats. But they are
used mostly in forms of composites. And fabrics woven with a high yarn count offer a moderate protection performance against
the knife stabbing due to the low shear strength. This research is focused on investigating the effect of the aramid core-spun
yarns on the stab resistance of the woven fabrics. With the aramid core-spun yarns with core to sheath weight ratio of 1 to
2.5 the armor specimens having different fabric densities were prepared and the knife edge impact test was conducted. On the
impact energy of the knife at the level 1 according to the NIJ standard, the drop tower test results demonstrated that fabric
density of the armor specimens affected the stab resistance significantly. The penetration depth of the impactor through the
armor specimens was associated with the thickness and mass of the armor sample in different ways. Being the stab resistance
introduced by considering the penetration depth of the impactor via thickness and weight per surface area, the effects of
the fabric conditions on the anti-stabbing property could be systematically analyzed and turned out that there was an optimal
level of the fabric density, showing the most effective stab resistance. 相似文献
74.
From the ether extract of Porella densifolia, the first liverwort collected and chemically investigated in Vietnam, a kaurane diterpenoid, ent-kauren-15-one (1) and two sesquiterpene norpinguisone (2) and norpinguisone methyl ester (3) have been purified. Their structures were elucidated by spectroscopic analysis. In addition, an X-ray crystal structure of norpinguisone was obtained, allowing to determine its stereochemistry. Furthermore, the inhibitory activity of nitric oxide (NO) production in RAW 264.7 cells stimulated by lipopolysaccharide (LPS) of compounds 1–3 was examined with their IC50 values of 69.4, 45.5 and 1.68 μM, respectively. 相似文献
75.
T.T.T. Duong 《Soil biology & biochemistry》2009,41(7):1475-3061
In many ecosystems, residues are added frequently to soil, in the form of root turnover and litter fall. However, in most studies on residue decomposition, residues are added once and there are few studies that have investigated the effect of frequent residue addition on C mineralization and N dynamics. To close this knowledge gap, we mixed mature wheat residue (C/N 122) into soil at a total rate of 2% w/w once at the start (R1×), every 16 days (R4×), every 8 days (R8×) or every 4 days (R16×). Un-amended soil served as control. All treatments were mixed every 4 days. Soil respiration was measured continuously over the 80-day incubation. Inorganic N, K2SO4-extractable C and N, chloroform-labile C and N (as an estimate of microbial biomass C and N), soil pH and microbial community composition were assessed every 16 days. Increasing frequency of residue addition increased C mineralization per g residue. Compared to R1×, cumulative respiration per g residue at the end of the incubation (day 80) was increased by 57, 82 and 92% in R4×, R8× and R16×, respectively. The largest differences in soil respiration per g residue occurred in the first 30 days. Despite large increases in cumulative respiration, frequent residue addition did not affect inorganic N or K2SO4-extractable N concentrations, chloroform-labile C and N or soil pH. Compared to the control, all residue treatments resulted in increases in chloroform-labile C and N and soil pH but decreased inorganic and K2SO4-extractable N. Microbial community composition was affected by residue addition, however there were no consistent differences among residue treatments. It is concluded that experiments with single residue additions may underestimate residue decomposition rates in the field. The increased C mineralization caused by frequent residue additions does not appear to be due to an increased microbial biomass or changes in microbial community composition, but rather to increased C mineralization per unit biomass. 相似文献
76.
77.
A new forest policy of allocating forestland to individual households for management and development, has been applied in
Vietnam since the early 1990s. This study was designed to examine how local forest-related people have used forestland and
forest resources under the new policy, and to determine their level of dependency on forests. An upland forest-related community
in northern central Vietnam, where the policy was introduced in 2002, was chosen as a case study. It was found that local
residents in the community have not complied with the forest allocation policy well, in that they violated the policy to freely
lend forestland to and borrow from villagers for cropping purposes, regardless of whether they were rich or poor, had enough
land or not, or were legally forest recipients. Regarding forest dependency, all households studied lived on forest resources
(forestland and forest products). More than 65% of the total annual income of poorer households was derived from the forest,
compared to less than 40% for the richer households. Forest-derived income accounted for more than 75% in their total income
in some of the poorest households.
相似文献
Nguyen Vinh QuangEmail: |
78.
Kien Trung LE Norikazu ISODA Lam Thanh NGUYEN Duc-Huy CHU Long VAN NGUYEN Minh Quang PHAN Diep Thi NGUYEN Tien Ngoc NGUYEN Tien Ngoc TIEN Tung Thanh LE Takahiro HIONO Keita MATSUNO Masatoshi OKAMATSU Yoshihiro SAKODA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):860
The impact of low pathogenicity avian influenza (LPAI) has been confirmed mainly in farms. Unlike apparent losses caused by the high pathogenicity avian influenza (HPAI), the LPAI impact has been hardly evaluated due to underestimating its spread and damage. In 2019, a questionnaire study was conducted in southern Vietnam to identify the specific risk factors of LPAI virus (LPAIV) circulation and to find associations between husbandry activities and LPAI prevalence. A multilevel regression analysis indicated that keeping Muscovy ducks during farming contributed to LPAIV positivity [Odds ratio=208.2 (95% confidence interval: 13.4–1.1 × 104)]. In cluster analysis, farmers willing to report avian influenza (AI) events and who agreed with the local AI control policy had a slightly lower risk for LPAIV infection although there was no significance in the correlation between farmer characteristics and LPAI occurrence. These findings indicated that keeping Muscovy ducks without appropriate countermeasures might increase the risk of LPAIV infection. Furthermore, specific control measures at the local level are effective for LPAIV circulation, and the improvement of knowledge about biosecurity and attitude contributes to reducing LPAI damage. 相似文献
79.
Antagonism of local isolates of Trichoderna spp. on citrus root rot disease by Fusarium solani in the mekong delta of vietnam 下载免费PDF全文
Duong Minh Jozef Coosemans Le Lam Cuong Ester Vandersmissen Pham Van Kim 《浙江大学学报(农业与生命科学版)》2004,30(4):392-392
The local isolates of Trichoderrma spp. and Fusariun solani were colected from citrus orchards in the Mekong delta of Vietnam and isolated on PDA, PDB and TSM medium for antagonism and Koch's postulate testing. The results showed that the high chitinolytic enzymes content of Trichoderma isolates can antagonise with Fusarium solani isolates by preventing the germination of Fusarium macroconidia in in-vitro condition. There are five promising isolates of Trichoderna spp. having high antagonism with Fusarium solani. These Trichoderma isolates also grew well in rice straws, maize stems, weeds and water hyacinth biowaste materials. These results supply the promising trend for biological control of root rot disease on citrus orchards of the Mekong delta. 相似文献
80.
Luan le Q Ha VT Uyen NH Trang le TT Hien NQ 《Journal of agricultural and food chemistry》2012,60(7):1737-1741
Degraded alginate compounds with molecular weights of 7-26, 40-77, or 11-26 kDa were obtained by γ irradiation, hydrogen peroxide (5% H(2)O(2)) treatment, or a combination treatment involving ionizing radiation and H(2)O(2), respectively. The 14 kDa oligoalginate, prepared by the combined method, promoted the growth of mustard greens and lettuce at an optimal concentration of 75 mg/L. The growth promotion effects of the oligoalginate prepared by γ irradiation in the presence of H(2)O(2) were statistically equivalent to those of the oligoalginate prepared by γ irradiation only. The combination of γ irradiation and H(2)O(2) reduced the required irradiation dosage by a factor of 9 relative to the oligoalginate produced by γ irradiation only. The combination treatment (γ irradiation/H(2)O(2)) may be carried out on a large scale at low cost to produce oligoalginate for use as a plant growth promoter in agricultural industries. 相似文献