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1.
K Miyazaki F Umenishi K Funahashi N Koshikawa H Yasumitsu M Umeda 《Biochemical and biophysical research communications》1992,185(3):852-859
Progelatinase A was purified as a complex with TIMP-2 from the conditioned medium of a human glioblastoma cell line. The TIMP-2/progelatinase complex was resistant to the activation by p-aminophenylmercuric acetic acid (APMA), and showed less than 10% of the activity of the TIMP-2-free active enzyme. When the complex was incubated with stromelysin in the presence of APMA, the 64-kDa progelatinase was effectively converted to the 57-kDa mature enzyme, increasing its gelatinolytic activity about 8-fold. These results suggest that stromelysin is a natural activator of TIMP-2-bound progelatinase A. 相似文献
2.
- Several animal species are known to distinguish between their own eggs and eggs of unrelated conspecifics. However, the cues involved in this discrimination are often unknown. These cues were studied using the predatory mite Gynaeseius liturivorus Ehara.
- Adult females of these predatory mites oviposit in clusters and avoid oviposition close to eggs laid by other females, resulting in reduced cannibalism between offspring. Because predatory mites are blind, it was tested whether volatiles of eggs were used as a cue for egg recognition.
- Adult female predatory mites were offered volatile cues of their own eggs and of unrelated conspecific eggs, and females were prevented from contacting the eggs. Predatory mites oviposited closer to their own eggs than to unrelated eggs. This preference was observed even when one own and one unrelated egg were offered as a volatile source.
- These results suggest that adult female predatory mites can determine kinship using volatiles released from the eggs.
3.
Increased expression in vivo and in vitro of foreign genes directed by A-type inclusion body hybrid promoters in recombinant vaccinia viruses. 下载免费PDF全文
S Funahashi S Itamura H Iinuma K Nerome M Sugimoto H Shida 《Journal of virology》1991,65(10):5584-5588
We constructed A-type inclusion body (ATI) hybrid promoters, that is, late ATI promoters followed by tandemly repeated early regions of the promoter for the 7.5-kDa protein (the 7.5-kDa promoter). The repetition of the whole early promoter sequence of the 7.5-kDa gene, including the upstream consensus sequence and initiation region, efficiently increased the early expression of the bacterial chloramphenicol acetyltransferase gene in recombinant vaccinia virus. Recombinant vaccinia virus could express influenza virus hemagglutinin via the hybrid promoter more efficiently, induced higher levels of neutralizing antibody and cytotoxic T lymphocytes, and consequently protected mice more efficiently against challenge with influenza virus than did recombinant vaccinia virus containing the widely used 7.5-kDa promoter. 相似文献
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Masayuki Nakamichi Fumiaki Cho Tetsuhiro Minami 《Primates; journal of primatology》1990,31(2):213-224
This study documents age-related changes in the interactions of wild-born cynomolgus macaque mothers and their infants living
in individual cages during the first 14 weeks of infant life. Body contact between mother and infant, maternal holding, and
infant sucking were found to decrease, and the mothers showed an increased frequency of aggression toward their infants with
age. These results were broadly similar to those reported for mother-infant interactions in other macaques living in social
groups. Nevertheless, a clear difference between the present cynomolgus macaques and other macaques in social groups was apparent.
The cynomolgus macaque mothers tended to permit their infants to move about freely without displaying maternal protectiveness
such as restraint or retrieval, unlike other macaque mothers in social groups. Such maternal behaviors might derive from the
experience of living in individual cages for many years and the relative safety of living in individual cages. The lack of
maternal restraint and retrieval could be responsible for the observed sex differences in behavior: male infants moved more
actively, and broke, and made contact with their mothers more frequently than did female infants. Moreover, mothers of female
infants held and groomed them more frequently and were less aggressive toward them. 相似文献
8.
Kenji Takeuchi Sayumi Shibamoto Makio Hayakawa Takamitsu Hori Keiji Miyazawa Naomi Kitamura Fumiaki Ito 《Experimental cell research》1996,223(2):420
Hepatocyte growth factor (HGF) stimulated cell migration of human gastric carcinoma cell lines MKN1, MKN7, and MKN28. Epidermal growth factor (EGF) also stimulated the cell migration of these three cell lines. In MKN7 cells, HGF-stimulated cell migration was rather reduced in the presence of EGF, whereas such an observation was not made with MKN1 and MKN28 cells. Therefore, we compared the effect of EGF on HGF-stimulated HGF receptor phosphorylation in these cell lines. HGF induced a rapid tyrosine phosphorylation of the HGF receptor in all these cell lines. In MKN7 cells, the increased phosphorylation was further enhanced by EGF, although EGF alone did not affect tyrosine phosphorylation of the HGF receptor. In MKN1 and MKN28 cells, EGF did not influence tyrosine phosphorylation of the HGF receptor, whether HGF was present or not. The data presented here suggest that EGF negatively modulates the cellular response to HGF by increasing tyrosine phosphorylation of the HGF receptor in certain types of epithelial cells, e.g., MKN7 cells. 相似文献
9.
It has been shown that mammalian neurogenesis is partly controlled by multiple basic helix–loop–helix (bHLH) genes, as inDrosophila.Recently, mouse homologs ofDrosophila atonal,a proneural gene encoding a bHLH protein required for chordotonal organ and photoreceptor development, have been characterized to obtain further insights into the molecular nature of mammalian neurogenesis. Here, to assess their potential involvement in genetic neural disorders, we have determined genetic map positions for four mouseatonal-related genes,Atoh1, Atoh2, Atoh3,andNdrf,which encode MATH-1, MATH-2, MATH-3, and NDRF, respectively. Interspecific backcross analysis indicated thatAtoh1andAtoh2were located in separate positions of Chr 6 and thatAtoh3andNdrfwere mapped to Chr 10 and Chr 11, respectively. Thus, these structurally related genes are located separately on multiple chromosomes. 相似文献
10.
Hideaki Sato Hideki Hirayama Takeshi Yamamoto Yoshimasa Lchio Fumiaki Ishizawa Michinao Mizugaki 《Luminescence》1994,9(2):73-77
The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction. 相似文献