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Koji MISUMI Yuri HIRAYAMA Misae SUZUKI Michiko NAKAI Hiroyuki KANEKO Junko NOGUCHI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2014,60(3):246-249
The present study was conducted to examine the feasibility of in vitro embryo production and transfer
technologies for producing Middle White piglets. After collection from three retired Middle White sows, a total of 222
oocytes were matured, fertilized and cultured in vitro, and a total of 50 embryos from the 4-cell to
blastocyst stage were produced by the 4th or 5th day. These embryos were transferred individually into three recipients along
with 5 in vivo-derived Duroc blastocysts. All of the recipients became pregnant, and they farrowed a total
of 9 Middle White and 9 Duroc piglets. These results suggest that in vitro embryo production using ovaries
from retired sows is useful for reproduction of pigs of pure breeds including the Middle White for breeding activities and
conservation/utilization of genetic resources. 相似文献
196.
Kazuki YAMAGAMI Nobuhiko YAMAUCHI Kaiyu KUBOTA Sho NISHIMURA Vishwajit Sur CHOWDHURY Kenichi YAMANAKA Masashi TAKAHASHI Shoji TABATA Masa-aki HATTORI 《The Journal of reproduction and development》2014,60(6):468-475
The forkhead box a (Foxa) protein family has been found to play important roles in mammals. Recently, the expression of Foxa2 was reported in the mouse uterus, and it was reported to be involved in regulation of implantation. However, the regulation of Foxa2 expression in the uterus is still poorly understood. Therefore, the present study was conducted to investigate the expressional profiles of Foxa2 in the rat uterus during the estrus cycle and pregnancy. Furthermore, the effect of steroid hormones and Hedgehog protein on the expression of Foxa2 was analyzed in vivo and in vitro. In this study, the level of expression of Foxa2 was low in the rat uterus during the different stages of the estrus cycle. However, the expression increased transiently during early pregnancy at 3.5 days post coitus (dpc) and decreased at 5.5 dpc. In ovariectomized rats, P4 treatment had no effect on the
expression of Foxa2 compared with the expression in control animals. Moreover, the expression of Foxa2 in cultured epithelial cells was not increased by P4 treatment in vitro. However, Foxa2 expression was significantly decreased in the rat uterus after 24 h of E2 treatment. Treatment of cells with a recombinant Hedgehog protein significantly increased the expression of Foxa2. These results suggest that the expression of Foxa2 may transiently increase just before the implantation and it may be regulated by E2 and Hedgehog protein. 相似文献
197.
Keisuke KOYAMA Sung-Sik KANG Weiping HUANG Yojiro YANAGAWA Yoshiyuki TAKAHASHI Masashi NAGANO 《The Journal of reproduction and development》2014,60(2):136-142
The objective of this research was to clarify the aging-related changes in in
vitro-matured bovine oocytes. Firstly, we examined the fertilization and
embryonic development of bovine oocytes after 22 and 30–34 h of in vitro
maturation (IVM). The oocytes after 30–34 h of IVM (penetrated by sperm at around 40 h
after starting IVM) showed a lower developmental rate to blastocysts (P<0.01), although
normal fertilization rates were similar regardless of IVM duration. In the next
experiment, reactive oxygen species (ROS), mitochondrial activity and ATP content in
oocytes after 20, 30 and 40 h of IVM were examined. The lowest level of ROS was found in
the group subjected to 30 h of IVM. The mitochondrial activity and ATP content in the
group subjected to 40 h of IVM were higher than in the group subjected to 20 h of IVM
(P<0.01), and those in the group subjected to 30 h of IVM showed intermediate values.
Thereafter, the mitochondrial activities at 3 days after in vitro
fertilization in embryos derived from the oocytes subjected to 22 and 34 h of IVM were
evaluated. In the group subjected to 34 h of IVM, high-polarized mitochondria were
frequently observed at the periphery of blastomeres. The present results suggest that high
mitochondrial activity observed in oocytes after prolonged IVM culture and localization of
high-polarized mitochondria at the periphery of blastomeres during early embryonic
development may be associated with the low developmental competence in aged bovine
oocytes. 相似文献
198.
Keisuke KOZAI Takuo HOJO Shota TOKUYAMA Anna Z SZóSTEK Masashi TAKAHASHI Miki SAKATANI Yasuo NAMBO Dariusz J SKARZYNSKI Kiyoshi OKUDA 《The Journal of reproduction and development》2014,60(2):150-154
Regression of the corpus luteum (CL) is characterized by a decay in progesterone
(P4) production (functional luteolysis) and disappearance of luteal tissues
(structural luteolysis). In mares, structural luteolysis is thought to be caused by
apoptosis of luteal cells, but functional luteolysis is poorly understood.
20α-hydroxysteroid dehydrogenase (20α-HSD) catabolizes P4 into its biologically
inactive form, 20α-hydroxyprogesterone (20α-OHP). In mares, aldo-keto reductase (AKR)
1C23, which is a member of the AKR superfamily, has 20α-HSD activity. To clarify whether
AKR1C23 is associated with functional luteolysis in mares, we investigated the expression
of AKR1C23 in the CL in different luteal phases. The luteal P4 concentration
and levels of 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNA were higher in the mid luteal
phase than in the late and regressed luteal phases (P<0.05), but the level of 3β-HSD
protein was higher in the late luteal phase than in the regressed luteal phase
(P<0.05). The luteal 20α-OHP concentration and the level of AKR1C23
mRNA were higher in the late luteal phase than in the early and mid luteal phases
(P<0.05), and the level of AKR1C23 protein was also highest in the late luteal phase.
Taken together, these findings suggest that metabolism of P4 by AKR1C23 is one
of the processes contributing to functional luteolysis in mares. 相似文献
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Fuminori Tanihara Michiko Nakai Nguyen Thi Men Noriko Kato Hiroyuki Kaneko Junko Noguchi Takeshige Otoi Kazuhiro Kikuchi 《Animal Science Journal》2014,85(4):395-404
The zona pellucida (ZP) is considered to play important roles in the prevention of polyspermy in mammalian oocytes. However, in pigs we have shown that the presence of the ZP accelerates sperm penetration into the ooplasm during in vitro fertilization (IVF). In the present study, we investigated the effects of the ZP on sperm binding, acrosomal status, and functional exposure of IZUMO, a critical factor involved in sperm‐egg fusion, during IVF in pigs. We evaluated the numbers and acrosomal statuses of sperm binding to the ZP and oolemma, and being present in the ZP and perivitelline space (PVS) using ZP‐intact and ZP‐free oocytes. More sperm bound to the ZP than to the oolemma. The average number of sperm present in the PVS was 0.44?0.51 per oocyte, and all sperm had lost their acrosomes. The proportion of sperm that were immunopositive for anti‐IZUMO antibody was significantly higher after they were passing or had passed through the ZP. Furthermore, addition of anti‐IZUMO antibody to the fertilization medium significantly inhibited the penetration of sperm into ZP‐free oocytes. These results suggest that, in pigs, the ZP induces the acrosome reaction, which is associated with the functional exposure of IZUMO, resulting in completion of fertilization. 相似文献