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排序方式: 共有512条查询结果,搜索用时 390 毫秒
1.
Kazuyoshi Nakata Tatsuo Hamano Ken-Ichi Hayashi Tadashi Kawai Seiji Goshima 《Fisheries Science》2001,67(3):449-455
SUMMARY: Preference for artificial burrows by the endangered Japanese crayfish species Cambaroides japonicus was studied to improve its cultivation. The occupation of artificial burrows, which were made from straight polyvinyl chloride pipes of different internal diameters ( Y , mm), by crayfishes of different total lengths ( X , mm) was significantly ( P < 0.001, n = 56) described by a linear regression: Y = 0.49 X + 3.42 (19.0 ≤ X ≤ 70.2). Among burrows of different lengths [crayfish total length (TL) × 1, × 2, × 3, and × 4], crayfishes significantly preferred burrows that were greater than TL × 3 ( P < 0.001, n = 588). 相似文献
2.
3.
This experiment was conducted to determine the effect of ruminal dosing of a mechanical stimulating brush on rumination time, ruminal passage rate and rumen fermentation status in steers fed a concentrate diet at maintenance level. Animals were dosed three Rumen Faibu (RF) per head through the rumen fistulae (RF treatment) and not dosed (control) in a change‐over design. The organic cell wall content of the concentrate diet was 12.7% of dry matter. Daily time spent on rumination was very short in both treatments with 24 min in RF treatment and 15 min in control. The turnover rate of ruminal fluid in RF treatment was higher than that in control. There were no differences in ruminal pH and total volatile fatty acid concentration between RF treatment and control. Acetic and butyric acid concentrations were not different between the treatments. Propionic acid concentration tended to be higher in the animals on RF treatment than in control animals. The RF dosing in Holstein steers fed a low fiber diet did not affect the rumination time, but increased rumen digesta passage rate and ruminal propionic acid production. 相似文献
4.
Tsutomu MATSUMOTO Yuichiro NARA Hiromitsu FURUYA Harumi TAKAHASHI Kiichi TAIRAKO Hideki YAMAMOTO 《Journal of General Plant Pathology》2002,68(4):382-384
L11A-Fukushima (L11A-F) derived from attenuated isolate LuA of Tomato mosaic virus (ToMV) has the highest ability to cross protect against virulent ToMV among LuA and its derivatives and is stably inherited.
Growth, yield, fruit quality and symptom attenuation of inoculated tomato plants did not differ significantly between L11A-F and L11A. The infectivity of progeny viruses in tomato infected with LuA-F was less than 4% of that with virulent ToMV. From these
results, L11A-F appears to possess the properties necessary for practical use. To manage L11A-F strictly, a PCR-based assay to detect trace contamination of virulent ToMV in L11A-F preparations was established.
Received 10 June 2002/ Accepted in revised form 30 October 2002 相似文献
5.
钙素对叶用莴苣营养吸收和生长发育的影响 总被引:12,自引:0,他引:12
采用NFT 栽培, 研究了叶用莴苣钙素与主要无机成分间的相互关系, 以及对叶用莴苣生长发育的影响。结果表明, 缺钙胁迫引起叶绿素含量降低, 缘腐病发病率上升, 叶片干、鲜样质量降低。生长中后期, 特别是新生内叶易发生钙素营养失调症。营养液中钙浓度过高会降低钾、镁的吸收, 而对氮、磷吸收影响不大。提高营养液中NH4+ -N 比例会抑制钙吸收, 降低其有效性。 相似文献
6.
Identification of sulfonylurea-resistant biotypes of paddy field weeds using a novel method based on their rooting responses 总被引:2,自引:0,他引:2
7.
Peru Gopal BISWAS Yuma OHARI Uday Kumar MOHANTA Tadashi ITAGAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):666
We analyzed the nuclear ribosomal internal transcribed spacer (ITS) 1 and ITS2 sequences for Bangladesh isolates of Ascaridia galli, and we determined that the sequences were unreliable as molecular markers for distinguishing A. galli from other Ascaridia species, because the sequences showed high identity with that of A. columbae. However, the ITS1 sequences were available for designing PCR primers distinguishable between Ascaridia galli and Heterakis spp. Bangladesh isolates of A. galli constituted a monophyletic clade along with other geographical isolates in the cytochrome c oxidase subunit I (COI) phylogenetic tree, however, we could not clarify the phylogenetic relationships between A. galli and other Ascaridia spp., because their available sequences in GenBank were very few. The developed PCR method using DNA from A. galli and Heterakis spp. eggs would enable differential diagnosis of the individual infections in the future. 相似文献
8.
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
9.
Expression dynamics of bovine MX genes in the endometrium and placenta during
early to mid pregnancy
Takahiro SHIROZU Keisuke SASAKI Manabu KAWAHARA Yojiro YANAGAWA Masashi NAGANO Nobuhiko YAMAUCHI Masashi TAKAHASHI 《The Journal of reproduction and development》2016,62(1):29-35
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has
antiviral activity. MX has at least two isoforms, known as MX1 and
MX2, in mammals. Moreover, bovine MX1 has been found to have alternative
splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is
temporarily produced from the conceptus before implantation and induces MX expression in the
endometrium. However, the expression dynamics of MX after implantation are not clear. In the
present study, we investigated the expression of MX1-a, MX1B and
MX2 in the endometrium and placenta before and after implantation along with the expression
of IFN-α, type I receptors (IFNAR1 and IFNAR2) and
interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were
divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples
were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P).
Although all the MX expressions were significantly higher in the IC and C at days 14–18,
presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C
and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC.
RT-PCR indicated IFNAR1, IFNAR2, IRF3 and
IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the
MX genes are affected by the type I IFN pathway during pregnancy and are involved in an
immune response to protect the mother and fetus. 相似文献
10.
Tokeshi I Yoshimoto T Muto N Nakamura S Ashizawa K Nakada T Tatemoto H 《The Journal of reproduction and development》2007,53(4):755-764
The present study was conducted to examine the effects of three tannin relatives (tannic acid, TA; gallic acid, GA; and ellagic acid, EA) on antihyaluronidase and reactive oxygen species (ROS) scavenging activity, in vitro fertilization (IVF) parameters, and the acrosome reaction (AR) induced by sperm-zona interaction. Among the three tannin relatives, TA and EA showed the strongest potency for blocking the hyaluronidase activity of boar sperm, with concentration-dependent inhibition over the range of 2-10 microg/ml. In contrast, ROSs were effectively scavenged by TA and GA, but not EA. When cumulus-free oocytes were inseminated in IVF medium containing 5 microg/ml of the tannin relatives, polyspermy was significantly reduced by TA and EA (32 and 29%, respectively) compared with oocytes treated with or without GA (51 and 69%, respectively) under conditions that maintained a high sperm penetration rate (P<0.05). Interestingly, induction of the AR by treatment of preincubated sperm with progesterone was blocked by TA and GA as a result of their higher levels of ROS scavenging activity, while EA, which possessed weak ROS scavenging activity, did not disturb induction of the AR with progesterone. However, the incidence of AR induced by sperm-zona interaction was significantly decreased by the strong antihyaluronidase actions of TA and EA compared with that in the absence of these compounds. Treatment with the compounds caused neither a protective proteolytic modification of the zona pellucida matrix before fertilization nor a reduction in acrosomal proteolytic activity or the number of zona-bound sperm. These findings suggest that the antihyaluronidase action of EA effectively prevents polyspermy by suppression of AR functionality induced by sperm-zona interaction and that hyaluronidase intervention is therefore required during porcine IVF. 相似文献