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91.
92.
Weidong Jiang Moon-Young Lim Hye-Joo Yoon Jeremy Thorner G. Steven Martin John Carbon 《Molecular & general genetics : MGG》1995,246(3):360-366
We find that overexpression in yeast of the yeast MCK1 gene, which encodes a meiosis and centromere regulatory kinase, suppresses the temperature-sensitive phenotype of certain mutations in essential centromere binding protein genes CBF2 and CBF5. Since Mck1p is a known serine/threonine protein kinase, this suppression is postulated to be due to Mck1p-catalyzed in vivo phosphorylation of centromere binding proteins. Evidence in support of this model was provided by the finding that purified Mck1p phosphorylates in vitro the 110 kDa subunit (Cbf2p) of the multimeric centromere binding factor CBF3. This phosphorylation occurs on both serine and threonine residues in Cbf2p. 相似文献
93.
L. H. S. Lim 《Systematic parasitology》1995,30(2):141-151
Three new species of Neocalceostomoides Kritsky, Mizelle & Bilqees, 1978 and Neocalceostoma elongatum Tripathi, 1957 were found on five species of Arius from Peninsular Malaysia. N. elongatum was collected from Arius sagor. A. venosus and A. maculatus, whereas Neocalceostomoides spinivaginalis n. sp., N. hamatum n. sp. and N. simplex n. sp. were obtained from A. thalassinus, A. sagor and A. caelatus, respectively. The three new species of Neocalceostomoides are similar to Neocalceostoma elongatum in the morphology of the soft anatomical parts and in having 14 marginal hooks, but differ in having the two anchors situated far apart without a connecting bar. The possibility that Neocalceostomoides and Neocalceostoma are synonymous is noted. The generic diagnosis of Neocalceostomoides is amended herein and a new family, the Neocalceostomatidae, is proposed to accommodate Neocalceostoma and Neocalceostomoides. 相似文献
94.
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96.
C.-H. LIM AND K.P. FLINT. 1995. Escherichia coli was heat stressed at 55, 60 or 65°C in sterile flasks of lake water. After 6 h at these temperatures the viable count on nutrient agar had dropped below the limits of detection (1 colony in 100 ml). The flasks were transferred to a 15°C incubator and left for 7 d. Recovery of the stressed E. coli was shown to occur within 48 h at this temperature. Recovery also occurred in microcosms amended with 5o (v/v) synthetic sewage. The stressed E. coli multiplied in the amended but not in the unamended microcosms. 相似文献
97.
Soo-Kyung Lim Jean-Pascal de Bandt Christian Aussel Pascal Pernet Jacqueline Giboudeau Luc Cynober 《Journal of cellular physiology》1995,162(3):422-426
This study investigates the short-tem effects of glucagon and human recombinant tumor necrosis factor α (TNFα) singly and in association on 2-methylaminoisobutyric acid (MeAIB) transport in hepatocyte monolayers. As expected, glucagon induced a time-dependent stimulation of MeAIB transport. In our experimental conditions, TNFα did not induce cytolysis. A 2 hour exposure to TNFα (0.05–500 ng/I) with or without glucagon (10?9 to 10?6 M) did not modify the basal or glucagon-stimulated MeAIB transport. Varying the duration of exposure to TNFα 5 ng/I up to 6 h was equally ineffective. The presence of hydrocortisone potentiated the glucagon-stimulated transport, but TNFα remained ineffective. Finally, the association of interferon (IFNγ) with TNFα and/or glucagon was unable to modify the transport activity. These data demonstrate that TNFα does not exert a direct effect on MeAIB transport in hepatocytes, at least on a short-term basis. © 1995 Wiley-Liss, Inc. 相似文献
98.
Boon Keng Lim 《Hydrobiologia》1997,358(1-3):297-299
Metamorphosis of fiddler crab Ilyoplax pusilla larvaefrom megalopal to first crab stage wasstudied in laboratory experiments under variousconditions of salinity and substratum. The hatchedzoea metamorphose through five stages before reachingmegalopal stage. The megalops were placed in a 20 mlPetri dishes (2–3 megalops/dish), with salinities of10, 20 or 30 . Each salinity level was tested eitherwith or without sandy mud substratum. Thirty to 35megalops were used in each of the six treatments. Theexperiment was carried out at a water temperature of28 ±0.5°C and with daily feeding of the diatomChaetoceros gracilis. Treatment of 20 salinity andsandy mud substratum revealed the highest metamorphicrate (87%), while in contrast no metamorphosis wasobserved at 30 salinity withoutsandy mud substratum. Duration of the metamorphosiswas about 16 days. Numerous malformed juvenile crabswere observed in treatments conductedwithout sandy mud substratum. 相似文献
99.
Giselle P. Lim Michael J. Russell Michael J. Cullen † Zoltán A. Tökés 《Journal of neurochemistry》1997,68(4):1606-1611
Abstract: We have previously reported that the amount of the neuronal matrix metalloproteinase (MMP) MMP-9, capable of cleaving β-amyloid1–40 predominantly at Leu34 -Met35 , is increased in a latent form in hippocampal specimens from AD patients and have suggested that the lack of activation of this enzyme may contribute to the deposition of β-amyloid in plaques. The current study addresses whether similar matrix proteinases are detectable in amyloid-positive and -negative brain specimens of aged beagles. Using quantitative zymography, three major neutral proteinases with molecular masses of 60, 95, and 280 kDa were readily detected. These enzymes have the characteristics of MMPs because they were inhibited by EDTA and 1,10-phenanthroline, and their activities were restored by addition of both Ca2+ and Zn2+ . The 95- and 280-kDa proteinases cross-reacted with specific monoclonal antibodies to human MMP-9 (gelatinase B; EC 3.4.24.35). Canine MMP-9 was latent because activation by organomercurial treatment resulted in a characteristic decrease in molecular mass. Statistical analysis revealed no difference in the 60-kDa proteinase activity in amyloid-positive and -negative brain specimens. However, significantly increased amounts of latent MMP-9 were observed in amyloid-positive brain specimens ( p ≤ 0.05) compared with amyloid-negative brain specimens. The observations document that changes in MMP-9 expression in amyloid-positive beagle brains are similar to those reported in the human Alzheimer's disease hippocampus and suggest the possibility that insufficient activation of MMP-9 may contribute to β-amyloid accumulation, a hypothesis that needs to be further investigated. 相似文献
100.
Pham Thi Huan Rona Taylor Alf A. Lindberg Naresh K. Verma 《Microbiology and immunology》1995,39(7):467-472
The glucosyl transferase gene (gtr) from bacteriophage phage X (SfX) caused partial conversion of serotype Y (group antigen 3, 4) to X (group antigen 7, 8) when introduced into a candidate vaccine strain of Shigella flexneri serotype Y (SFL124). The gtr gene caused conversion of O-antigens but did not eliminate the adsorption of the corresponding phage SfX. The hybrid strain expressing both group antigens 7, 8 and 3, 4 showed 75% protection when immunized guinea pigs were challenged with a wild-type S. flexneri serotype X strain. No protection was observed against serotype Y challenge, although group antigen 3, 4 was detected in the LPS of the hybrid strain. This suggests the importance of O-antigen immunity in the host defense against shigellosis. 相似文献