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排序方式: 共有233条查询结果,搜索用时 15 毫秒
1.
Deborah M. Thompson Frank W. Edens Gerald A. LeBlanc R. Michael Roe 《Pesticide biochemistry and physiology》2004,80(3):131-142
Trypsin modulating oostatic factor (TMOF), a peptide hormone originally isolated from the ovaries of adult Aedes aegypti, is currently under commercial development as a new pesticide chemistry with a novel mode of action for the control of larval mosquitoes. The objective of the current research is to evaluate potential risks of the use of TMOF as an insecticide on non-target organisms. TMOF (YDPAP6) was degraded in vitro (as determined by HPLC and LC/MS) to DPAP6, PAP6, and then AP6 by leucine aminopeptidase, a pancreatic enzyme found in the digestive system of vertebrates. The rate of degradation of TMOF and PAP6 was significantly greater than that of DPAP6, while no metabolism of AP6 was found. TMOF technical insecticide was produced on a commercial scale by recombinant yeast (heat-killed before application). The technical TMOF when administered in a single dose by gavage to male and female mice at 2000 mg dry weight/kg body weight produced no negative effects as compared to controls up to 12 days after treatment. When male and female mallard ducks were treated by gavage with 1250 mg dry weight of technical TMOF/kg body weight each day for 5 days, again no toxic effects were noted through 35 days after the last treatment. TMOF technical insecticide was also applied to the shaved skin of male and female rabbits at the rate of 2000 mg/kg for 1-2 days, with no effect. The end point observations in these in vivo experiments were mortality; changes in growth rate, behavior, body structure, and color; and possible lesions observed during necropsy. Finally, Daphnia incubated with technical TMOF in rearing water at the level of 1.0 × 106 yeast cells/ml (10 mg/ml) also demonstrated no negative effects on mortality, growth, molting, time to first brood, and production of viable neonates. It appears from these studies that TMOF can be degraded by vertebrate digestive proteases and technical TMOF is not toxic to the non-target organisms examined. 相似文献
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Akihito TAKAHASHI Ajalli RAHIM Miki TAKEUCHI Emiko FUKUI Midori YOSHIZAWA Kuniaki MUKAI Makoto SUEMATSU Hidetoshi HASUWA Masaru OKABE Hiromichi MATSUMOTO 《The Journal of reproduction and development》2016,62(1):43-49
Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1]
or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted
to extraembryonic regions during the postimplantation period and detected marked expression in mouse
Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the
postimplantation period, suggesting that it plays a physical and physiological role in embryo development
and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to
determine the role of Tinagl1 during embryonic development and pregnancy, we generated
Tinagl1-deficient mice. Although Tinagl1–/– embryos were not
lethal during development to term, homologous matings of Tinagl1–/– females and
Tinagl1–/– males showed impaired fertility during pregnancy, including failure
to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with
equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did
not differ between Tinagl1–/– and Tinagl1flox/flox.
In vitro fertilization followed by embryo culture also demonstrated the normal
developmental potential of Tinagl1-null embryos during the preimplantation period. Our
results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and
they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1
is related to fertility in adult females but is not essential for either fertilization or preimplantation
development in vitro. 相似文献
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一枝蒿制剂对小鼠小肠运动作用研究 总被引:1,自引:0,他引:1
用两种一枝蒿制剂对小鼠进行小肠推进实验,以甲基硫酸新斯地明、盐酸吗啡和生理盐水为对照。结果表明:一枝蒿健胃促消化机制主要是促进小肠运动。经方差分析和多重比较,其效果相似于硫酸甲基新斯地明 相似文献
8.
Involvement of histone H2B monoubiquitination in the regulation of mouse preimplantation development
Masatoshi OOGA Masataka G. SUZUKI Fugaku AOKI 《The Journal of reproduction and development》2015,61(3):179-184
Histone H2B monoubiquitination (H2Bub1) plays an important role in developmental regulation in various vertebrate species. However, the role of H2Bub1 in mammalian preimplantation development remains unclear. In the present study, we examined the role of H2Bub1 in the regulation of mouse preimplantation development. Based on immunocytochemical analysis using an anti-H2Bub1 antibody, no H2Bub1 signal was detected in the metaphase chromosomes of unfertilized oocytes or the pronuclei of early 1-cell stage embryos, but a weak signal was observed in late 1-cell stage embryos. The signal increased after cleavage into the 2-cell stage, and thereafter a strong signal was observed until the blastocyst stage. To assess the significance of H2Bub1 in the regulation of preimplantation development, RNF20 (an H2B-specific ubiquitin E3 ligase) was knocked down using small interfering RNA (siRNAs). In embryos treated with siRNA, the levels of Rnf20 mRNA and H2Bub1 decreased
at the 4-cell and morula stages. Although these embryos developed normally until the morula stage, only one-third developed into the blastocyst stage. These results suggested that H2Bub1 is involved in the regulation of preimplantation development. 相似文献
9.
Background
This study was conducted to investigate effect of exogenous melatonin on the development of mouse mature oocytes after cryopreservation.Results
First, mouse metaphase II (MII) oocytes were vitrified in the open-pulled straws (OPS). After warming, they were cultured for 1 h in M2 medium containing melatonin at different concentrations (0, 10−9, 10−7, 10−5, 10−3 mol/L). Then the oocytes were used to detect reactive oxygen species (ROS) and glutathione (GSH) levels (fluorescence microscopy), and the developmental potential after parthenogenetic activation. The experimental results showed that the ROS level and cleavage rate in 10−3 mol/L melatonin group was significantly lower than that in melatonin-free group (control). The GSH levels and blastocyst rates in all melatonin-treated groups were similar to that in control. Based on the above results, we detected the expression of gene Hsp90aa1, Hsf1, Hspa1b, Nrf2 and Bcl-x1 with qRT-PCR in oocytes treated with 10−7, or 10−3 mol/L melatonin and untreated control. After warming and culture for 1 h, the oocytes showed higher Hsp90aa1 expression in 10−7 mol/L melatonin-treated group than in the control (P < 0.05); the Hsf1, Hsp90aa1 and Bcl-x1 expression were significantly decreased in 10−3 mol/L melatonin-treated group when compared to the control. Based on the above results and previous research, we detected the development of vitrified-warmed oocytes treated with either 10−7 or 0 mol/L melatonin by in vitro fertilization. No difference was observed between them.Conclusions
Our results indicate that the supplementation of melatonin (10−9 to 10−3 mol/L) in culture medium and incubation for 1 h did not improve the subsequent developmental potential of vitrified-warmed mouse MII oocytes, even if there were alteration in gene expression. 相似文献10.
Yoshiki SHIRAKATA Yuuki HIRADATE Hiroki INOUE Eimei SATO Kentaro TANEMURA 《The Journal of reproduction and development》2014,60(5):383-387
The core histone is composed of four proteins (H2A, H2B, H3 and H4). Investigation of the modification patterns of histones
is critical to understanding their roles in biological processes. Although histone modification is observed in multiple cells
and tissues, little is known about its function in spermatogenesis. We focused on the modification patterns of histone H4
during murine spermatogenesis. We demonstrated that the individual N-terminal sites of H4 show different modification
patterns during the differentiation of male germ cells. The methylation pattern varied depending on the residues that were
mono-, di-, or tri-methylated. All the H4 modifications were high during the meiotic prophase, suggesting that histone H4
modification plays an important role during this stage of spermatogenesis. Elongating spermatids showed increased acetylation
of histone H4, which may be associated with a histone-to-protamine substitution. Our results provide further insight into the
specific relationship between histone H4 modification and gene expression during spermatogenesis, which could help to
elucidate the epigenetic disorders underlying male infertility. 相似文献