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821.
J O'Connor D Ballantyne JG Pollock B Cairney TD Lawrie 《Canadian Metallurgical Quarterly》1977,27(3):325-331
Fourteen patients with hyperlipoproteinaemia and peripheral vascular disease have been investigated to determine the effect on limb blood flow of hypolipidaemic therapy. Satisfactory lowering of serum lipoprotein levels was achieved in the treated group. There was a significant deterioration in peak reactive blood flow measurements in the placebo group compared with the treated group. Treatment of hyperlipoproteinaemia may, therefore, be of value in preventing the progression of peripheral atherosclerosis. 相似文献
822.
This paper presents evidence that the Snyder/Pope Visual Memory Technique utilizing the Bender-Gestalt Test is a useful predictor of reading ability for first grade children. Subjects were administered the Bender Visual Memory Technique, the Bender-Gestalt Test, and the Digit Span subtest of the WISC-R at the beginning of first grade. The same children were administered the Reading subtest of the Wide Range Achievement Test at the end of first grade. Category scores of the Visual Memory Technique were correlated with the reading achievement results. One category, Rcc (an error-free recall of an error-free original drawing), correlated significantly with later reading ability (r = .43, p = .01). The Digit Span and reading achievement relationship was not found to be significant. Short-term visual recall is probably highly related to the reading task at Grade 1 and should be assessed when children begin to learn to read. Diagnosticians are encouraged to use the technique with attention to the precision category, Recall correct from correct. 相似文献
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825.
CD10 (CALLA) antigen is expressed in a wide variety of epithelial and nonepithelial tissues, but its most significant application is in the diagnosis and classification of certain types of malignant lymphoma and leukemia. CD10 is expressed in a high percentage of cases of acute lymphoblastic leukemia (ALL), follicular lymphoma, Burkitt's lymphoma, and some hematopoietic tumors. Although the antigen is not lineage specific, CD10 expression is widely used to define subgroups within B-ALL and is a useful tool for detecting the presence of leukemic blasts in the bloodstream. Currently available monoclonal antibodies to CD10 have been found to be effective only in fresh-frozen tissue and for techniques such as flow cytometry. We have used a recombinant protein corresponding to the whole of CD10 to generate a monoclonal antibody that is effective in paraffin-embedded tissue sections. We have used this antibody to assay for the presence of CD10 on a range of normal and pathological tissues. Strong staining was seen in lymphoid germinal centers, renal tubules, glomeruli, syncytiotrophoblast, hepatic parenchymal canaliculi, B-lineage ALL, follicle center cell lymphoma, and a proportion of cases of large-B-cell lymphoma. We believe that this antibody will be of value in the characterization of malignant lymphoma, in particular the differential diagnosis of small-B-cell lymphoma and subtyping of lymphoblastic leukemia, as well as the investigation of the significance of expression of CD10 in other normal and pathological tissues. 相似文献
826.
RJ Gorelick RE Benveniste TD Gagliardi TA Wiltrout LK Busch WJ Bosche LV Coren JD Lifson PJ Bradley LE Henderson LO Arthur 《Canadian Metallurgical Quarterly》1999,253(2):259-270
All retroviruses (except the spumaretroviruses) contain a nucleocapsid (NC) protein that encodes one or two copies of the Zn2+-finger sequence -Cys-X2-Cys-X4-His-X4-Cys-. This region has been shown to be essential for recognition and packaging of the genomic RNA during virion particle assembly. Additionally, this region has been shown to be involved in early infection events in a wide spectrum of retroviruses, including mammalian type C [e.g., murine leukemia virus (MuLV)], human immunodeficiency virus type 1 (HIV-1), Rous sarcoma virus, and other retroviruses. Mutations in the two Zn2+-fingers of the NC protein of simian immunodeficiency virus strain Mne [SIV(Mne)] have been generated. The resulting virions contained the normal complement of processed viral proteins with densities indistinguishable from wild-type SIV(Mne). All of the mutants had electron micrograph morphologies similar to those of immature particles observed in wild-type preparations. RNA packaging was less affected by mutations in the NC protein of SIV(Mne) than has been observed for similar mutants in the MuLV and HIV-1 systems. Nevertheless, in vitro replication of SIV(Mne) NC mutants was impaired to levels comparable to those observed for MuLV and HIV-1 NC mutants; replication defective NC mutants are typically 10(5)- to 10(6)-fold less infectious than similar levels of wild-type virus. One mutant, DeltaCys33-Cys36, was also found to be noninfectious in vivo when mutant virus was administered intravenously to a pig-tailed macaque. NC mutations can therefore be used to generate replication defective virions for candidate vaccines in the SIV macaque model for primate lentiviral diseases. 相似文献
827.
TD Nguyen MW Moody M Steinhoff C Okolo DS Koh NW Bunnett 《Canadian Metallurgical Quarterly》1999,103(2):261-269
Proteinase-activated receptor-2 (PAR-2) is a G protein-coupled receptor that is cleaved by trypsin within the NH2-terminus, exposing a tethered ligand that binds and activates the receptor. We examined the secretory effects of trypsin, mediated through PAR-2, on well-differentiated nontransformed dog pancreatic duct epithelial cells (PDEC). Trypsin and activating peptide (AP or SLIGRL-NH2, corresponding to the PAR-2 tethered ligand) stimulated both an 125I- efflux inhibited by Ca2+-activated Cl- channel inhibitors and a 86Rb+ efflux inhibited by a Ca2+-activated K+ channel inhibitor. The reverse peptide (LRGILS-NH2) and inhibited trypsin were inactive. Thrombin had no effect, suggesting absence of PAR-1, PAR-3, or PAR-4. In Ussing chambers, trypsin and AP stimulated a short-circuit current from the basolateral, but not apical, surface of PDEC monolayers. In monolayers permeabilized basolaterally or apically with nystatin, AP activated apical Cl- and basolateral K+ conductances. PAR-2 agonists increased [Ca2+]i in PDEC, and the calcium chelator BAPTA inhibited the secretory effects of AP. PAR-2 expression on dog pancreatic ducts and PDEC was verified by immunofluorescence. Thus, trypsin interacts with basolateral PAR-2 to increase [Ca2+]i and activate ion channels in PDEC. In pancreatitis, when trypsinogen is prematurely activated, PAR-2-mediated ductal secretion may promote clearance of toxins and debris. 相似文献