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945.
SM Serrano Y Hagiwara N Murayama S Higuchi R Mentele CA Sampaio AC Camargo E Fink 《Canadian Metallurgical Quarterly》1998,251(3):845-853
Two forms of a proteinase, KN-BJ 1 and 2, were purified to homogeneity from the venom of Bothrops jararaca. In SDS/PAGE reduced KN-BJ 1 and 2 migrated as single bands with molecular masses of 38 kDa and 39 kDa. The two enzymes have similar N-terminal amino acid sequences and specific activities on synthetic chromogenic substrates, and both release bradykinin from bovine low-molecular-mass kininogen. KN-BJ 1 and KN-BJ 2 clot fibrinogen with specific activities of 245 NIH U/mg and 219 NIH U/mg, releasing only fibrinopeptide A. The amidolytic, kinin-releasing and coagulant activities are inhibited by phenylmethylsulfonyl fluoride, demonstrating that KN-BJ is a serine proteinase. Benzamidine derivatives, which are competitive inhibitors of trypsin-like proteinases, also inhibited the amidolytic activity of KN-BJ. A cDNA clone (HS104, 2.2 kb) has been isolated from a cDNA library of B. jararaca venom glands with an ORF of 771 bp. The deduced amino acid sequence contains segments that are identical to the sequences of the N-terminus and three tryptic peptides of KN-BJ 2. Therefore, the cDNA is believed to represent the gene of KN-BJ 2. The deduced amino acid sequence indicates that KN-BJ 2 is synthesized as a prezymogen of 257 amino acids with a putative signal peptide of 18 amino acids and an activating peptide of six amino acid residues. The sequence of 233 amino acids representing the mature enzyme exhibits high similarity to sequences of serine proteinases isolated from crotalid venoms. 相似文献
946.
AC Vallinoto VN Azevedo DE Santos S Caniceiro FC Mesquita WW Hall MO Ishak R Ishak 《Canadian Metallurgical Quarterly》1998,93(3):407-409
PURPOSE: To report surgical management of solitary hepatic metastasis that occurred 25 years after an enucleation for uveal melanoma. METHODS: A 16-year-old girl, diagnosed with choroidal melanoma and treated with enucleation, was found 25 years later to have liver metastasis affecting the entire left lobe of the liver. RESULTS: She underwent partial hepatectomy with removal of the metastatic melanoma. Four years later, she was found to have a smaller circumscribed nodular melanoma in the remaining right lobe of the liver, also treated with resection. She has remained disease-free for 2 years, with no evidence of systemic disease. CONCLUSION: Surgical excision may be a useful treatment option in selected cases with solitary, circumscribed liver metastasis from uveal melanoma. 相似文献
947.
EA Drucker SM Rivitz JA Shepard PM Boiselle B Trotman-Dickenson TJ Welch TP Maus SW Miller JA Kaufman AC Waltman TC McLoud CA Athanasoulis 《Canadian Metallurgical Quarterly》1998,209(1):235-241
Male pigeons, Columba livia, employ intense mate guarding and frequent copulation apparently as strategies to ensure their paternity. The aim of this study was to investigate the benefits to females of mate guarding by males and frequent copulation. Field observations showed that females initiated the majority of copulations and females that solicited copulations more frequently were guarded more closely by their partner. Experimental removal of guarding male partners showed that: (1) unguarded, fertile females suffered increased harassment from extrapair males which reduced their foraging efficiency; and (2) unguarded, fertile females did not seek copulations with extrapair males. Various explanations for frequent pair copulation initiated by females are discussed and we conclude that female pigeons trade pair copulations for protection (mate guarding) against sexual harassment from other males. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
948.
O Eton DD Kharkevitch MA Gianan MI Ross K Itoh MW Pride C Donawho AC Buzaid PF Mansfield JE Lee SS Legha C Plager NE Papadopoulos AY Bedikian RS Benjamin CM Balch 《Canadian Metallurgical Quarterly》1998,4(3):619-627
Advances in transdermal therapeutic systems (TTS) and the technology involved have been rapid because of the sophistications of physiology and biology on skin, enhancing methodology for the skin penetration of drugs, and material and polymer sciences on the pharmaceutical additives. In this review paper, such progress was introduced and the future on the TTS was augured. 相似文献
949.
Several lines of evidence are provided indicating that our visual percept can be dominated by spatial aliasing for viewing conditions near those needed to see the spatial frequency doubled illusion. The apparent aliasing effect indicates that the underlying sampling array has a density 15-30% of that of M-cells, in agreement with the known proportion of Y-like M-cells (M(y)-cells). The presence of aliasing indicates, that there is a separate irregular array of M(y)-cells, and that their role is to rapidly convey information on retinal gain control to the brain rather than to act primarily as inputs to image motion computation. 相似文献
950.
L Chi LJ Saganek KL Rogers TE Mertz AL Metz AC Uprichard KP Gallagher 《Canadian Metallurgical Quarterly》1998,39(4):193-202
RATIONALE AND OBJECTIVES: After intraarticular application of gadolinium (Gd)-DTPA the visualization cartilage surface roughness is limited because of diffusion into the cartilage. To improve the sensitivity of magnetic resonance (MR) arthrography to diagnose cartilage surface abnormalities, the authors have tested liposome-entrapped contrast agents. METHODS: Using paramagnetic contrast agents (Gd-DTPA and manganese chloride) free and entrapped in liposomes, respectively, high resolution MR imaging investigations were performed at 7.1 tesla on intact pig temporomandibular and rabbit knee joints. RESULTS: After intraarticular injection of the liposome-entrapped contrast agents an excellent contrast between cartilage surface and joint space was achieved. Diffusion of the contrast agent into the cartilage layer was prevented and the visualization of the cartilage surface was improved markedly. Small mechanically and enzymatically induced cartilage lesions could be assessed reliably. CONCLUSIONS: Intraarticular injection of liposome-entrapped contrast agents can improve the potential of MR arthrography concerning the detection of early osteoarthritic cartilage changes. 相似文献