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81.
N B Cooper V F Allison J E Ubelaker 《Zeitschrift für Parasitenkunde (Berlin, Germany)》1975,46(3):229-239
Transmission electron microscopy of the scolex of the 8-day-old Hymenolepis diminuta cysticercoid demonstrates its resemblance to the scolex of the adult. A syncytial tegument composed of external and internal layers is connected by cytoplasmic extensions. Fully developed microtriches are present. Furthermore, a basement membrane, muscle layers, and medullary region containing flame cells, nerve tissue, and other cell bodies are observed. Of particular interest is the presence of discrete sensory endings whose function is discussed. 相似文献
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D J Hosking A Williams R B Godwin-Austen S P Allison 《BMJ (Clinical research ed.)》1975,3(5976):136-138
A 16-year-old epileptic developed chorea. He had osteomalacia, hypocalcaemia, and hyperphosphataemia, which were due not to hypoparathyroidism but to vitamin D deficiency--itself secondary to longstanding dietary deficiency and anticonvulsant drug administration. 相似文献
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A major radioactive peptide, T1, was resolved by high-performance liquid chromatography from a tryptic digest prepared from the F1-ATPase from the thermophilic bacterium PS3 which had been inactivated with p-fluorosulfonylbenzoyl[3H]inosine. Two radioactive peptides, T1P1 and T1P2, were isolated from a peptic digest of T1 by high-performance liquid chromatography. The sequences of T1P1 and T1P2 were shown to be E-E-H-X-Q-V-A-R and E-E-H-X-Q, respectively, where X corresponds to derivatized Tyr-364 of the beta subunit. 相似文献
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S. P. Allison 《BMJ (Clinical research ed.)》1994,309(6967):1499-1500
Until the results of early intervention trials are known, computed tomography should be used selectively rather than routinely in all patients with stroke. Scanning may be advised in young patients (under 65 years) or in those with an atypical course where there is diagnostic doubt and computed tomography would influence management. The cost and medicolegal implications of routine scanning are enormous and should be considered carefully in relation to other and possibly more effective strategies. 相似文献
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M A Handel J Papaconstantinou D P Allison E M Julku E T Chin 《Developmental biology》1973,35(2):240-249
During the mid to late 4th instar period of larval development, the mitochondria of Rhynchosciara spermatocytes undergo highly characteristic morphological changes. In late meiosis the enlarged mitochondria fuse to form a single mitochondrial element which will ultimately extend the length of the spermatid tail. Our studies have shown that synthesis of a circular DNA occurs during this period of mitochondrial “differentiation.” This DNA has a density of 1.681 g/cm3; and its synthesis cannot be detected in somatic tissues such as salivary gland, fat body, or gastric cecum. From analysis of DNA extracted from mitochondrial pellets, we have shown that the circular DNA is associated with the mitochondria. The contour length of the mitochondrial DNA is 9 μm, equivalent to a molecular weight of 18 × 106. Although most metazoan mitochondrial DNAs exhibit contour lengths of approximately 5 μm (10 × 105 daltons), there is no extractable 5 μm circular DNA in these spermatocytes. Therefore, we conclude that either Rhynchosciara spermatocytes possess a distinct 9 μm mitochondrial DNA or that the spermatocyte mitochondrial DNA represents dimers of 5 μm monomers. 相似文献
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