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91.
ME Raichle RL Grubb MH Gado JO Eichling MM Ter-Pogossian 《Canadian Metallurgical Quarterly》1976,33(8):523-526
To test the hypothesis that regional cerebral blood flow (rCBF) is normally regulated by regional metabolic activity, rCBF and the regional cerebral metabolic rate for oxygen (rCMRO2) were compared in selected human subjects. In normal subjects and patients with chronic, stable diseases of brain, rCBF correlated well with rCMRO2. In one individual with mild dementia, rCBF and rCMRO2 were measured before and during exercise of the hand and forearm contralateral to the hemisphere studied. Appropriate parallel changes occurred in both rCBF and rCMRO2 during hand exercise. In patients with acute diseases affecting the hemisphere studied, however, the correlation between rCBF and rCMRO2 was unpredictable. 相似文献
92.
Varioliform gastric erosion is a common lesion which can be reliably diagnosed radiologically. The diagnosis was established in 27 (1.7%) of 1,600 detailed radiological examinations made in 1975. There was a good correlation with gastroscopic findings. 相似文献
93.
WJ Rosskopf RW Woerpel SR Yanoff EB Howard JO Britt 《Canadian Metallurgical Quarterly》1981,62(10):777-779
94.
JO Utgaard J Frengen T Stigbrand A Ullen R Schmid T Lindmo 《Canadian Metallurgical Quarterly》1996,42(10):1702-1708
A new immunometric two-site sandwich assay is introduced, in which a label-scavenging binding partner is added to the sample in addition to the analyte-binding partner. The scavenger binding partner binds excess label antibody, giving a signal proportional to the amount of excess label antibody in the sample solution. A set of two calibration curves is obtained from the two binding partners simultaneously, and a combination of the two signals gives an unambiguous determination of the analyte concentration, even for high analyte concentrations where the hook effect may occur. Two-particle immunofluorometric assays developed for placental alkaline phosphatase and human chorionic gonadotropin on the basis of this principle and yielding signals measured by flow cytometry gave rapid results (2 h) and had working ranges in excess of 5 and 6 orders of magnitude for the respective analytes. 相似文献
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Ataxia-telangiectasia (A-T) is a rare hereditary syndrome involving cerebellar degeneration, immunodeficiency, cancer risk, and radiosensitivity. Since the cloning of the A-T gene, ATM, in 1995, research on this pleiotropic disease and its molecular basis has expanded tremendously. ATM is a large protein kinase that appears to be one of the primary sensors of DNA strand-break damage. The vast majority of mutations in ATM result in truncation and destabilization of the protein, but certain missense and splicing errors have been shown to result in a less severe phenotype. A-T heterozygotes have been shown to have a slightly increased risk of cancer, but their increased in vitro radiosensitivity does not seem to result in any in vivo sensitivity. ATM does seem to act as a classic tumor suppressor gene in T-prolymphocytic leukemia, and LOH at the ATM locus is a common event in some tumor types, suggesting a general role for ATM in cancer. Recent work has shown the interaction of ATM with proteins involved in cell cycle control, and the direct phosphorylation of some of these interactors by ATM. ATM knockout mice have been created by several groups, and recapitulate the immunodeficiency, radiosensitivity, cancer risk, and fertility defects of A-T, although the effect on the cerebellum is slight. These diverse topics, and their integration into a global understanding of A-T, were the basis of the 7th International A-T Workshop. 相似文献
100.
Although the product of the UL12 gene of herpes simplex virus type 1 (HSV-1) has been shown to possess both exonuclease and endonuclease activities in vitro, and deletion of most of the gene within the viral genome results in inefficient production and maturation of infectious virions, the function of the deoxyribonuclease (DNase) activity per se in virus replication remains unclear. In order to correlate the in vitro and in vivo activities of the protein encoded by UL12, mutant proteins were tested for nuclease activity in vitro by a novel hypersensitivity cleavage assay and for their ability to complement the replication of a DNase null mutant, AN-1. Rabbit reticulocyte lysates programmed with wild-type UL12 RNA cleaved at the same sites cleaved by purified HSV-1 DNase, but distinct from those cleaved by DNase 1 or micrococcal nuclease. All mutants which lacked DNase activity in vitro also failed to complement the replication of AN-1 in nonpermissive cells. Likewise, all mutants which contained HSV-1 DNase activity, as detected by the hypersensitivity cleavage assay, were capable of complementing the replication of the DNase null mutant, though to varying extents. Of particular note was the d1-126 mutant protein, which, despite having the same specific activity as the wild-type enzyme in vitro, complemented the replication of AN-1 significantly less than the wild-type protein. The results suggest that DNase activity per se is required for efficient replication of HSV-1 in vivo. However, residues, including the N-terminal 126 amino acids, which are dispensable for enzymatic activity in vitro may facilitate the accessibility or activity of the protein in vivo. 相似文献