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排序方式: 共有1728条查询结果,搜索用时 31 毫秒
1.
Oussama El Far Béatrice Marquèze Christian Leveque Nicole Martin-Moutôt Bethan Lang John Newsom-Davis †Akira Yoshida †Masami Takahashi Michael J. Seagar 《Journal of neurochemistry》1995,64(4):1696-1702
Abstract: In Lambert-Eaton myasthenic syndrome neurotransmitter release is reduced by an autoimmune response directed against the calcium channel complex of the nerve terminal. Autoantibodies were detected by immunoprecipitation assays using solubilized receptors labeled with ligands selective for N-type (125 I-ω conotoxin GVIA) and L-type ([3 H]PN200-110) calcium channels. Sera with a high antibody titer (>3 n M ) against rat brain N-type channels contained autoantibodies that immunoprecipitated neuronal and muscle L-type channels. These IgG fractions stained a 55-kDa protein in immunoblots of purified skeletal muscle dihydropyridine receptor, suggesting that they contain autoantibodies against the β subunit of the calcium channel. A distinct antibody population in the same fractions reacted with a nerve terminal 65-kDa protein that is unrelated to the β subunit and displays properties similar to those of synaptotagmin. 相似文献
2.
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
3.
Ruofan Wang Camille R. Simoneau Jessie Kulsuptrakul Mehdi Bouhaddou Katherine A. Travisano Jennifer M. Hayashi Jared Carlson-Stevermer James R. Zengel Christopher M. Richards Parinaz Fozouni Jennifer Oki Lauren Rodriguez Bastian Joehnk Keith Walcott Kevin Holden Anita Sil Jan E. Carette Nevan J. Krogan Andreas S. Puschnik 《Cell》2021,184(1):106-119.e14
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.
6.
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
7.
A 17 year-old boy was admitted to the hospital because of thirst, polyuria (5-61/day), delayed sexual development and muscle weakness. He appeared obese, had an eunuchoidal body habitus and was excessively tall. Chromosomal analysis revealed a 47XXY karyotype. Serum cortisol was 1.3 microgram/dl, LH, 10.4 mIU/ml, FSH, 2.0 mIU/ml, and testosterone, 10 ng/dl. Endocrinological dynamic tests indicated diabetes insipidus and hypopituitarism of a hypothalamic type. Brain CT disclosed the existence of a tumor shadow around the calcified pineal body, extending towards the suprasellar region. Replacement therapy with glucocorticoid and DDAVP was started. The patient complained of a headache and plasma AFP and hCG concentrations were 868 ng/ml and 68.6 IU/ml respectively. A hCG- and AFP- producing germ cell tumor was suspected and radiation therapy with 60Co was performed. Plasma AFP and hCG were decreased with significant clinical improvement. Soon after irradiation, he started to complain of a headache and had elevated AFP and hCG levels. Right hemiparesis and unconsciousness suddenly appeared and he died of left thalamic bleeding. This is the first case of Klinefelter's syndrome associated with intracranial germ cell tumor. Plasma testosterone levels fluctuated in parallel with the change in plasma hCG levels. This shows that the Leydig cells in this patient could respond to some extent to tumor-producing hCG. 相似文献
8.
Kan-ichi Watanabe Toshihide Takasawa Fuminobu Yoshimura Masami Ozeki Masamitsu Kawanami Hiroshi Kato 《FEMS microbiology letters》1992,92(1):47-55
A major immunodominant surface protein (the 75-kDa protein) of Porphyromonas (Bacteroides) gingivalis 381 has been purified and its amino-terminal amino acid sequence has been determined. Using oligonucleotide probes corresponding to the sequence, we identified a recombinant plasmid clone carrying a single 4.2-kb BamHI fragment from pUC19 libraries of P. gingivalis. The BamHI fragment transferred to the bacteriophage T7 RNA polymerase/promoter expression vector system produced a slightly larger (77-kDa) protein, a precursor form, immunoreactive to the antibody against the 75-kDa protein, suggesting that the cloned DNA fragment probably carried an entire gene for the 75-kDa protein. Genomic Southern analysis revealed a single copy of the 75-kDa protein gene per genome among all P. gingivalis strains tested, and that no homologous genes are present in other black-pigmented Bacteroides species. These observations suggest that the 75-kDa protein gene may be useful as a specific DNA probe to classify or to detect this organism. 相似文献
9.
The inactivation of papain brought about by low concentration of urea or guanidine hydrochloride was found to be a non-competitive type and that of cyanate ion to be a mixed type. The results are presented as Lineweaver-Burk plots.These inactivations are not due to a change in the secondary structure of papain molecule as a result of the measurements of optical rotatory dispersion, circular dichroism, and UV-difference spectra. 相似文献
10.