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排序方式: 共有2210条查询结果,搜索用时 31 毫秒
1.
Masami Takagi 《Oecologia》1985,68(1):1-6
Summary
Pteromalus puparum is a gregarious parasitoid of many butterfly pupae. Adult size, mortality, and sex ratio of P. puparum, as a parasitoid of Papilio xuthus, were unit weight of the host. Effects of female size on fecundity, wing load, and longevity were also examined.The highest total weight of progeny from the host was attained when the number of eggs per gram of the host was approximately 150. Positive correlations were observed between the size of the females and their fecundity and wing load. The maximum longevity of the female kept with honey but without hosts was attained when the initial number of parasitoids per g of the host was 150.Considering the total fecundity of all female progeny, the reproductively most efficient number of eggs to be deposited per g of the host was estimated to be approximately 300. However, as shortage of food for the adult females strongly affects their fecundity, the reproductively most efficient number of eggs to be deposited per g of the host was about 70 when the adult female progeny was not provided with food.The optimal number of eggs to be deposited when the emale oviposits in the host under field conditions is discussed. 相似文献
2.
Abstract. A technique for fine-scale vegetation mapping with the aid of low-altitude aerial photography was developed. The procedure is as follows: 1. The site is divided into a lattice pattern - in case the site is too large to fit into a single photograph with satisfactory resolution. The coordinates of every lattice point are surveyed to be used as control points for geometric correction. A photograph of each block of the lattice is taken using a remote-controlled camera system lifted by a captive helium balloon. 2. The vegetation is classified on the basis of a phytosociological survey. 3. The shapes and locations of vegetation patches appearing in the photographs are entered into a computer, using a digitizer. A geometric correction is carried out through coordinate transformation referring to the coordinates of the control points and subsequently a draft vegetation map is produced. Finally, discrepancies are corrected and the map is coloured to produce the final version of the vegetation map. This technique was applied to vegetation mapping at a bar, 500 m wide and 2 km long, in the river Yoshino in Shikoku, Japan. A fine-scale vegetation map was obtained and used to analyse the influence of plants on geomorphic processes and community-specific hydrogeomorphic conditions on the bar. 相似文献
3.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
4.
Barbara Tillmann Pierre Jolic?ur Masami Ishihara Nathalie Gosselin Olivier Bertrand Yves Rossetti Isabelle Peretz 《PloS one》2010,5(4)
Congenital amusia is a neurogenetic disorder of music processing that is currently ascribed to a deficit in pitch processing. A recent study challenges this view and claims the disorder might arise as a consequence of a general spatial-processing deficit. Here, we assessed spatial processing abilities in two independent samples of individuals with congenital amusia by using line bisection tasks (Experiment 1) and a mental rotation task (Experiment 2). Both amusics and controls showed the classical spatial effects on bisection performance and on mental rotation performance, and amusics and controls did not differ from each other. These results indicate that the neurocognitive impairment of congenital amusia does not affect the processing of space. 相似文献
5.
Identification of a new 84/82 kDa calmodulin-binding protein, which also interacts with actin filaments, tubulin and spectrin, as synapsin I 总被引:4,自引:0,他引:4
A new 84/82 kDa calmodulin-binding protein, which also interacts with actin filaments, tubulin and spectrin, was purified from the bovine synaptosomal membrane. The binding of calmodulin to this protein was Ca2+-dependent, and was inhibited by trifluoperazine, the association constant being calculated to be 2.2 X 10(6) M-1. Maximally, 1 mol of calmodulin bound to 1 mol of the purified protein. This protein was phosphorylated by both kinase II (Ca2+- and calmodulin-dependent kinase) and cyclic AMP-dependent kinase. In addition, antibody against this protein was demonstrated to have an immunological crossreactivity with synapsin I in the synaptosomal membrane. 相似文献
6.
Mutagenesis of human granulocyte colony stimulating factor 总被引:9,自引:0,他引:9
T Kuga Y Komatsu M Yamasaki S Sekine H Miyaji T Nishi M Sato Y Yokoo M Asano M Okabe 《Biochemical and biophysical research communications》1989,159(1):103-111
To define the structure-function relationship, we have made a number of mutants of human granulocyte colony-stimulating factor (hG-CSF) by in vitro mutagenesis. The results indicate that most of the mutations located in the internal and C-terminal regions of the molecule abolished the activity, whereas the mutants without N-terminal 4, 5, 7, or 11 amino acids retained the activity. N-terminal amino acids were also altered by cassette mutagenesis using a synthetic oligonucleotide mixture. Among them, KW2228, in which Thr-1, Leu-3, Gly-4, Pro-5 and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg and Ser, showed more potent granulopoietic activity than that of intact hG-CSF both in vitro and in vivo. 相似文献
7.
Masatsugu Hatakeyama Tetsuya Nakamura Kyu Beom Kim Masami Sawa Tikahiko Naito Kugao Oishi 《Development genes and evolution》1990,198(7):389-394
Summary Mature eggs dissected from ovaries of unmated females of Athalia rosae (Hymenoptera: Tenthredinidae), if placed on a filter-paper soaked with distilled water, are activated and develop to haploid males. Occasionally, however, diploid females develop from these artificially activated eggs. Treatment of mature unfertilized eggs dissected from diploid females with ice-cold temperatures immediately before activation and with a high temperature (36° C) upon and immediately after activation resulted in the production of diploid males, diploid females, triploid females and gynandromorphs at high frequency. The same treatment of mature unfertilized eggs dissected from triploid females resulted in the production of only triploid survivors. These results, together with the results on the segregation of a marker mutation, yellow fatbody (yfb), appear to indicate that meiotic divisions were complete in the treated eggs, and that all four nuclei became potentially capable of participating in development with or without automictic fusion.Studies on the sawfly, Athalia rosae (Insecta, Hymenoptera, Tenthredinidae), part V 相似文献
8.
Tau proteins: the molecular structure and mode of binding on microtubules 总被引:29,自引:17,他引:12
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Tau is a family of closely related proteins (55,000-62,000 mol wt) which are contained in the nerve cells and copolymerize with tubulin to induce the formation of microtubules in vitro. All information so far has indicated that tau is closely apposed to the microtubule lattice, and there was no indication of domains projecting from the microtubule polymer lattice. We have studied the molecular structure of the tau factor and its mode of binding on microtubules using the quick-freeze, deep-etch method (QF.DE) and low angle rotary shadowing technique. Phosphocellulose column-purified tubulin from porcine brain was polymerized with tau and the centrifuged pellets were processed by QF.DE. We observed periodic armlike elements (18.7 +/- 4.8 nm long) projecting from the microtubule surface. Most of the projections appeared to cross-link adjacent microtubules. We measured the longitudinal periodicity of tau projections on the microtubules and found it to match the 6-dimer pattern better than the 12-dimer pattern. The stoichiometry of tau versus tubulin in preparations of tau saturated microtubules was 1:approximately 5.0 (molar ratio). Tau molecules adsorbed on mica took on rodlike forms (56.1 +/- 14.1 nm long). Although both tau and MAP1 are contained in axons, competitive binding studies demonstrated that the binding sites of tau and MAP1A on the microtubule surfaces are most distinct, although they may partially overlap. 相似文献
9.
Masao Ohkuchi Masami Tsukamoto Toru Yokoyama Masami Shiratsuchi Yasumi Uchida 《Prostaglandins & other lipid mediators》1988,36(6)
To isolate and identify the plasma factor which stimulates prostaglandin I 2 production by rat aortic ring, a human plasma fraction which showed a major stimulating activity on prostaglandin I 2 production was purified by ultrafiltrate, Sephadex G-10 gel filtration and QAE-Sephadex column chromatography. The purified plasma factor was identified as acid by its ultraviolet and infrared absorption spectroscopy, and 1H nmr and 13C nmr spectroscopy. The stimulating activity of the purified plasma factor and that of authentic uric acid coincided with each other. The stimulating potency of uric acid at its physiological concentration in human plasma (about 50 μg/ml) was half of the deproteinized human plasma, and was about 30 fold stronger than that of L-tryptophan, a cofactor of prostaglandin hyperoxidase. 相似文献
10.