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11.
Biotope roofs in Japan are usually intensive green roofs that primarily include native plants and food plants for invertebrates and a pond and stones to create a wide range of habitats. The study aimed to evaluate the survivability of planted species, and colonisation by plants and invertebrates on a biotope roof and to suggest an appropriate planting design and maintenance scheme to optimize biodiversity benefits. An intensive green roof (150 m2, substrate depth of 50 cm) was installed in 2002 on the ninth storey of a building at Chiba University, Japan. Twelve species of trees, 18 species of shrubs and 8 species of forbs (mainly native species) were planted and volcanic stones were used as mulch and to create habitats for invertebrates. No maintenance and no irrigation were applied for almost 8 years. A limited number of tree species, such as Myrica rubra and Cinnamomum camphora could grew well without maintenance and irrigation at a substrate depth of 50 cm. Overall, shrubs grew successfully and a high density planting seemed effective in increasing wind resistance. Most forbs disappeared, probably because of drought and competition with these colonising plants. Eleven plant species spontaneously colonised resulting in domination by Solidago altissima and Miscanthus sinensis. These two species were too aggressive, and selective weeding is required for species richness. In an invertebrate study, 46 species in 11 orders were observed and the highest number of invertebrate species was observed in the pond and shady areas.  相似文献   
12.
F1-adenosine triphosphatase (ATPase) is an ATP-driven rotary molecular motor in which the central gamma subunit rotates inside a cylinder made of three alpha and three beta subunits alternately arranged. The rotor shaft, an antiparallel alpha-helical coiled coil of the amino and carboxyl termini of the gamma subunit, deeply penetrates the central cavity of the stator cylinder. We truncated the shaft step by step until the remaining rotor head would be outside the cavity and simply sat on the concave entrance of the stator orifice. All truncation mutants rotated in the correct direction, implying torque generation, although the average rotary speeds were low and short mutants exhibited moments of irregular motion. Neither a fixed pivot nor a rigid axle was needed for rotation of F1-ATPase.  相似文献   
13.
Recently, 3-O-octanoyl-(+)-catechin (OC) was synthesized from (+)-catechin (C) by incorporation of an octanoyl chain into C in the light of (-)-epicatechin gallate (ECg) and (-)-epigallocatechin gallate (EGCg), which are the major polyphenols found in green tea and have strong physiological activities. OC was found to inhibit the response of ionotropic gamma-aminobutyric acid (GABA) receptors (GABA(A) receptors) and Na+/glucose cotransporters expressed in Xenopus oocytes in a noncompetitive manner more strongly than does C. OC also induced a nonspecific membrane current and decreased the membrane potential of the oocyte, and thus death of the oocyte occurred even at lower concentrations than that induced by C or EGCg. Although EGCg produced H2O2 in aqueous solution, OC did not. This newly synthesized catechin derivative OC possibly binds to the lipid membrane more strongly than does C, Ecg, or EGCg and as a result perturbs the membrane structure.  相似文献   
14.
An aminopeptidase, Jc-peptidase, was purified from Japanese cedar pollen by seven steps, including precipitation with ammonium sulfate, ion-exchange chromatography, gel filtration, hydrophobic interaction chromatography on phenyl-agarose, and high-performance liquid chromatography. Purified Jc-peptidease has a molecular weight of 42 kDa and hydrolyzes the synthetic substrates of L-phenylalanyl-4-methylcoumaryl-7-amide (Phe-MCA) with Km = 5 x 10(-5) M, Tyr-MCA with Km = 7 x 10(-4) M, Leu-MCA with Km = 1 x 10(-3) M, and Met-MCA with Km = 1 x 10(-3) M. Other MCA analogues such as Arg-MCA or Glu-MCA failed to serve as its substrates. The activity was inhibited in the presence of phebestin, [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valyl]-L-phenylalanine, with Ki = 4.7 x 10(-5) M, or bestatin, [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-L-leucine, with Ki = 1.1 x 10(-4) M. According to amino acid sequence analysis, the N-terminal amino group seems to be blocked. The physiological function of the aminopeptidase (Jc-peptidase) has not been clarified in vivo.  相似文献   
15.
This study examined the association between redox status in the oviduct and early embryonic death in heat-stressed mice. In Experiment 1, non-pregnant mice were heat-stressed at 35 C with 60% relative humidity for 12, 24, or 36 h, and the maternal redox status was verified by measuring the levels of reactive oxygen species (ROS) and free radical scavenging activity (FRSA) in the oviduct, and thiobarbituric acid reactive substances (TBARS) and glutathione peroxidase (GSH-Px) activity in the liver. In Experiment 2, zygotes were collected from mice heat-stressed for 12 h on the day of pregnancy, and their developmental abilities were assessed in vitro, along with the intensity of DNA damage at the 2-cell stage. The TBARS value and GSH-Px activity in the liver, and ROS level in the oviduct were significantly higher in heat-stressed mice, and this increase appeared to depend on the duration of the heat stress. Maternal heat stress significantly reduced the percentage of zygotes that developed to the morula and blastocyst and the total cell number in the blastocyst. In addition, DNA damage at the 2-cell stage was significantly higher in maternally heat-stressed embryos. These results suggest that heat stress induces systemic changes in redox status in the maternal body, and the resultant increase in oxidative stress in the oviduct is possibly involved in heat stress-induced early embryonic death .  相似文献   
16.
Much evidence has suggested that sex steroid hormone-induced growth of uterine cells is mediated by polypeptide growth factors synthesized in uterine tissues. The present study aimed to clarify the effect of insulin-like growth factor-I (IGF-I) on the proliferation of mouse endometrial stromal cells obtained from immature mice. IGF-I and IGF-I receptor (type I) mRNAs were detected in the endometrial stromal cells. IGF-I increased bromodeoxyuridine (BrdU) uptake in the endometrial stromal cells, indicating an increase in DNA replication. E2 increased IGF-I mRNA levels in the endometrial stromal cells. IGF-I receptor is a tyrosine kinase receptor, and treatment with genistein, a tyrosine kinase inhibitor, reduced IGF-I-induced BrdU-uptake in the endometrial stromal cells. IGF-I signaling pathways involve mitogen-activated protein (MAP) kinase and phosphatidylinositol-3 kinase (PI-3 kinase). Treatment with 10(-7) M of the MAP kinase inhibitor PD098059 and 10(-5) M of the PI-3 kinase inhibitor LY294002 decreased IGF-I-induced BrdU-uptake in the endometrial stromal cells. However, LY294002 (10(-5) M) also decreased the BrdU-uptake in the absence of IGF-I treatment. These results suggest that endometrial IGF-I is involved in the proliferation of endometrial stromal cells in a paracrine or autocrine manner, and that the MAP kinase pathway is involved in DNA replication of endometrial stromal cells.  相似文献   
17.
OBJECTIVE: To determine whether high intracranial pressure (ICP) during spontaneous ventilation (SV) in anesthetized horses coincides with an increase in intracranial elastance (ie, change in ICP per unit change of intracranial volume). ANIMALS: 6 adult horses. PROCEDURE: Anesthesia was induced and maintained in each horse for 5 hours with isoflurane at a constant dose equal to 1.2 times the minimum alveolar concentration. Direct ICP measurements were obtained by use of a strain gauge transducer inserted in the subarachnoid space, and arterial blood pressure was measured from a carotid artery. Physiologic responses were recorded after 15 minutes of normocapnic controlled ventilation (CV) and then after 10 minutes of SV. Aliquots (3 mL) of CSF were removed from each horse during SV until ICP returned to CV values. Slopes of pressure-volume curves yielded intracranial elastance. RESULTS: Intracranial elastance ranged from 0.2 to 3.7 mm Hg/mL after removal of the first aliquot of CSF Slopes of pressure-volume curves were largest following removal of the initial CSF aliquot, but shallow portions of curves were detected at relatively high ICPs (25 to 35 mm Hg). A second-order relationship between SV ICP and initial intracranial elastance was found. CONCLUSIONS AND CLINICAL RELEVANCE: In horses anesthetized with isoflurane, small changes in intracranial volume can cause large changes in ICP Increased intracranial elastance could further exacerbate preexisting intracranial hypertension. However, removal of small volumes of CSF may cause rapid compensatory replacement from other intracranial compartments, which suggests steady-state maintenance of an increase in intracranial volume during isoflurane anesthesia in horses.  相似文献   
18.
OBJECTIVE: To examine relationships between the ratio of energy intake to basal metabolic rate (EI/BMR) and age and body mass index (BMI) among Japanese adults. DESIGN: Energy intake was assessed by 4-day semi-weighed diet records in each of four seasons (16 days in total). The EI/BMR ratio was calculated from reported energy intake and estimated basal metabolic rate as an indicator of reporting accuracy. SETTING: Residents in three areas in Japan, namely Osaka (urban), Nagano (rural inland) and Tottori (rural coastal). SUBJECTS: One hundred and eighty-three healthy Japanese men and women aged > or =30 years. RESULTS: The oldest age group (> or =60 years) had higher EI/BMR values than the youngest age group (30-39 years) in both sexes (1.74 vs. 1.37 for men; 1.65 vs. 1.43 for women). In multiple regression analyses, age correlated positively (partial correlation coefficient, beta = 0.012, P < 0.001 for men; beta = 0.011, P < 0.001 for women) and BMI correlated negatively (beta = -0.031, P < 0.001 for men; beta = -0.025, P < 0.01 for women) with EI/BMR. CONCLUSION: Age and BMI may influence the relative accuracy of energy intake among Japanese adults.  相似文献   
19.
Protecting pigs from simultaneous infection with avian, swine, and human influenza viruses would be an effective strategy to prevent the emergence of reassortants with pandemic potential. M2 protein is a candidate antigen for so-called 'universal vaccines,' which confer cross-protection to different influenza viruses in a strain- and subtype-independent manner. We tested whether a recombinant F gene-deleted Sendai virus vector that contained an M2 gene derived from an H5N1 avian influenza virus (SeV/ΔF/H5N1M2) could induce a cross-reactive antibody response to the extracellular domain of M2 protein (M2e) in pigs. SeV/ΔF/H5N1M2 induced an antibody response to M2e when the vector was inoculated intramuscularly. The antibodies induced by SeV/ΔF/H5N1M2 cross-reacted with M2e derived from different avian, swine, and human influenza viruses. In mice, however, SeV/ΔF/H5N1M2 did not confer cross-protection to challenge with a heterologous H3N2 influenza virus. Our results confirm those of other groups indicating that antibodies to M2e do not mediate protection to influenza viruses in pigs.  相似文献   
20.
We investigated the effects of warming the basal ends of Carolina poplar (Populus × canadensis Moench.) softwood cuttings at controlled low-air-temperature on their root growth and leaf damage after planting. The warming treatment was applied to the cuttings by soaking 10 mm beyond the cut end in warmed water maintained at 30 °C in a cold chamber maintained at an air temperature of 10 °C and a photosynthetic photon flux density (PPFD) of 10 μmol m?2 s?1 (near the light compensation point at 10 °C) until rooting was observed. The warmed cuttings were then grown in a growth chamber at an air temperature of 30 °C, relative humidity 85–90 %, and a PPFD of 100 μmol m?2 s?1. Control cuttings were grown in the growth chamber throughout the experiment. Rooting occurred simultaneously for both warmed and control cuttings, irrespective of air temperature. Root development was greater and leaf damage, evaluated on the basis of extent of necrosis, was less for warmed cuttings than for control cuttings. The reduction of leaf damage for warmed cuttings probably resulted from reduced post-planting water stress and leaf senescence, because of improved root development as a result of the pre-planting warming treatment. This technique could improve the propagation of cuttings of woody plants, because it would ensure that the cuttings are ready to develop roots with minimum loss of carbohydrates, irrespective of weather conditions.  相似文献   
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