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141.
Lemna perpusilla 6746, a short-day duckweed, flowered undercontinuous illumination on M-sucrose medium containing CuSO4,AgNO3 and HgCl2, which are SH-inhibitors. The optimum concentrationsof CuSO4, AgNO3 and HgCl2 were 5, 1 and 20 µM, respectively.Other metal ions tested were ineffective, but at least two otherSHinhibitors, potassium ferricyanide and iodoacetamide, alsoinduced long-day flowering at the concentrations of 0.1-1 µM. Adding 50 µM EDTA to the medium prevented the effect ofcupric ion, but not that of other SH-inhibitors. EDTA at 200µM induced some long-day flowering when added to a mediumwith no SH-inhibitors. It also permitted some flowering whenadded together with cupric ion, and accelerated flowering inthe presence of the other SHinhibitors listed above. EDTA andSH-inhibitor effects appeared to be additive. (Received May 25, 1973; )  相似文献   
142.
The histamine contents were very low in the whole bodies of various types of mutant mice (Wv/Wv, Wv/W, W/W), in which the number of mast cells was decreased, but the L-histidine decarboxylase activities in these mutant mice were not much lower than in control wild type mice. These findings suggest the presence of high histidine decarboxylase activity in cells other than mast cells. Histidine decarboxylase in the whole body of mice was difficult to assay, because the enzyme was rapidly destroyed by proteases, but inclusion of a protease inhibitor, such as Leupeptin, Antipain, Chymostatin, or Pepstatin in the assay mixture permitted the accurate assay of histidine decarboxylase in crude extracts.  相似文献   
143.
The Ogasawara (Bonin) Islands are oceanic islands of volcanic origin located in the northwestern Pacific Ocean about 1,000 km south of the Japanese mainland. A large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis, is endemic to the islands but its closest relative is unknown. The Ogasawara Islands are geographically closest to the Japanese Archipelago, but this area is inhabited only by species of a different subgenus, Alloxylocopa. Thus, X. ogasawarensis is commonly thought to have originated from other members of Koptortosoma, which is widely distributed in the Oriental tropical region. In this study, we investigated the origin of X. ogasawarensis using a phylogenetic analysis of Xylocopa based on four genes: mitochondrial cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b), and nuclear elongation factor-1alpha (EF-1alpha) and phosphoenolpyruvate carboxykinase (PEPCK). A combined analysis of the four genes strongly suggests that Koptortosoma is a large, polyphyletic group, within which Alloxylocopa is embedded. Xylocopa ogasawarensis emerged as the species most closely related to Alloxylocopa and not to Oriental species of Koptortosoma. Contrary to previous views of the origin of X. ogasawarensis, our results suggest that X. ogasawarensis and Alloxylocopa share a common origin and diverged after they colonized the island regions of East Asia.  相似文献   
144.
Lemna perpusilla 6746, a short-day duckweed, flowered undercontinuous illumination if some of the SH inhibitors, such ascyanide or tungstate were added to the M-sucrose medium. Theeffect of tungstate was not overcome by simultaneous applicationof molybdate, but deletion of the Mo from the medium was enoughto induce the long-day flowering. In vivo assay of nitrate reductaseactivity suggested that nitrate reduction was not inhibitedby tungstate, CuSO4 or AgNO3 which induced longday flowering.The possibility was suggested that suppression of some Mo-requiringprocess other than nitrate reduction brings about the long-dayflowering in this plant. (Received November 12, 1975; )  相似文献   
145.
Underwater observations of two living individuals and an examination of a freshly dead individual of the rare deep-sea fish Triodon macropterus revealed that they usually have the large ventral flap completely uplifted and seamlessly retracted into the abdominal region of the trunk: one individual was collected at a depth of 280 m by hook and line east of Tonaki-jima Island, Ryukyu Islands, and kept in a tank at the Okinawa Churaumi Aquarium for six years; the second living individual was observed by the ROV Hakuyo 2000 at a depth of 275 m east of Ishigaki-jima Island, Ryukyu Islands; and another individual collected at depths of 250?350 m by hook and line off Funchu Point, Yoron-jima Island (27°00.15’N, 128°26.06’E), Ryukyu Islands, provided an opportunity to demonstrate that the ventral flap could be manually uplifted by rotating the pelvis. When the ventral flap was uplifted in all of these specimens, whether naturally or manually, there were no scaleless linear bands or streaks and gaps evident in the skin between the retracted ventral flap and the abdominal region. The fine structure of the scales of the body and the ventral flap was observed by light microscopy, scanning electron microscopy, and X-ray CT scanning. The scales of the ventral flap are arranged in rows radiating from the antero-dorsal part of the ventral flap where the anterior part of the pelvis articulates with and rotates around the pectoral girdles. The orientation of the rows on the ventral flap changes from a posterior direction dorsally to a posteroventral direction more ventrally. A ridge with many sharp serrations is raised and bent from the edge of each scale on the body and ventral flap. The raised ridges on the lower scales on the ventral flap become packed together with the upper scales to form a seamless surface when the ventral flap is uplifted into the abdominal region.  相似文献   
146.

Introduction

Early experience with low-quality roughage has the potential to improve its utilization in ruminants.

Objectives

This study determined the effects of early experience with low-quality roughage on dry matter intake (DMI), body weight (BW) and the hepatic metabolism of lambs.

Methods

Ten lambs (3 month old) were randomly allocated to two treatments: the low-quality roughage group (LR) or the control group (C). The study lasted 7 months. In the first 4 months, LR was fed low-quality roughage, whereas C was fed normal roughage. In the last 3 months, both groups were fed low-quality roughage. Dry matter intake (DMI) was determined at the 1st, 3rd, 5th and 7th months (P1, P2, P3 and P4). Analysis of liver tissue metabolomics were carried out in P2 and P3.

Results

DMI was greater in LR than C in P1 (p?<?0.05), but did not differ in P2. In P3 and P4, DMI was greater in LR than in C (p?<?0.01). The concentration of five glycolysis/gluconeogenesis intermediates, some lipid metabolism-related metabolites, six amino acids and several amino acid metabolism-related metabolites were different between treatments in P2. From P2 to P3, concentrations of these metabolites changed in LR. However, no difference was found between treatments in P3.

Conclusion

Feeding low-quality roughage to lambs early in life influenced hepatic glycolysis/gluconeogenesis, fatty acid oxidation and amino acid metabolism. However, for lambs who had no early experience with low-quality roughage, similar alterations were induced in the liver after 1 month of eating low-quality roughage.
  相似文献   
147.
A highly practicable synthesis of both enantiomers of 3-hydroxypipecolic acid derivatives 1, 2, 3, 4 is described. Screening of these molecules for glycosidase inhibition has been examined. Compound 3 was shown to be a potent inhibitor of beta-N-acetylglucosaminidase as well as Escherichia coli beta-glucuronidase.  相似文献   
148.
A reliable nuclear transfer method was first reported in 1983; it provided definite evidence that parthenogenetic embryos are lethal at early postimplantation in mammals. Subsequently, nuclear transfer has been extensively used as an important and versatile tool for investigating embryo and somatic-cell cloning and nucleo-cytoplasmic interactions. Further development of this technique has enabled the generation of bimaternal embryos containing two haploid sets of maternal genomes from female germ cells of different origins. By using a 2-d nuclear transfer system for oocyte reconstruction, viable mice can be produced solely from maternal genomes, without the participation of the paternal genome. This oocyte reconstruction system, as described in this protocol, could provide valuable guidelines for exploring the potential endowments of gametes and for conferring novel properties to them.  相似文献   
149.
150.
Fas ligand (FasL) has been implicated in cytotoxic T lymphocyte (CTL)- and natural killer (NK) cell-mediated cytotoxicity. In the present study, we investigated the localization of FasL in murine CTL and NK cells. Immunocytochemical staining showed that FasL was stored in cytoplasmic granules of CD8+ CTL clones and in vivo activated CTL and NK cells, where perforin and granzyme A also resided. Immunoelectron microscopy revealed that FasL was localized on outer membrane of the cytoplasmic granules, while perforin was localized in internal vesicles. Western blot analysis showed that the membrane-type FasL of 40 kDa was stored in CD8+ CTL clones but not in CD4+ CTL clones. By utilizing a granule exocytosis inhibitor (TN16), we demonstrated that FasL translocated onto cell surface upon degranulation of anti-CD3-stimulated CD8+ CTL clones. Moreover, TN16 markedly inhibited the FasL-mediated cytotoxicity by CD8+ T cell clones and NK cells. These results suggested a substantial contribution of FasL to granule exocytosis-mediated target cell lysis by CD8+ CTL and NK cells.  相似文献   
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