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71.
Gordon Winocur Fergus I M Craik Brian Levine Ian H Robertson Malcolm A Binns Michael Alexander Sandra Black Deirdre Dawson Heather Palmer Tara McHugh Donald T Stuss 《Journal of the International Neuropsychological Society》2007,13(1):166-171
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed. 相似文献
72.
Ian F. Gutteridge 《Clinical & experimental optometry》1987,70(5):138-144
Data on the prevalence of all ocular conditions seen in 1500 consecutive optometric patients were obtained during an investigation into the effectiveness of routine visual field screening. In many instances, these are the first prevalence figures for optometric patient populations. Some of the estimates of prevalence are compared with other optometric and general population surveys. Many disorders were observed, the most frequent being slight to moderate increases in retinal arterial reflex and attenuation, optic cup/disc ratio of 0.4, shallow anterior chambers and family history of glaucoma. The occurrence of some conditions was sporadic, resulting from the relatively small sample. However, this survey may serve as an audit of ocular disease detection for other practitioners. 相似文献
73.
Ian A. Chisholm Stephen M. Drance Teresa To 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1989,227(2):110-113
Visual-field areas to a I2e stimulus were measured planimetrically using an X-Y digitizer and a computer program. Sampling of normal subjects and patients suspected of having glaucoma was done at two points in time. Calculations of eye-wall stress were done using ultrasonic data and intra-ocular pressure (IOP) measurements from patient records. For those suspected of having glaucoma who developed chronic open-angle glaucoma (COAG), the time of transition was the second point in time. The visual field area was regressed against patient age at the two points in time. No difference in the regression slopes was found for the normal subjects and unchanged patients. The patients who did develop glaucoma were significantly different. The mean annual rate of visual-field change (rate of decay) was calculated and found to be 28.5 mm2/year for the normals, 153.5 mm2/year for the suspects, and 376.4 mm2/year for those patients who developed glaucoma. The rate of visual-field decay only correlated with patient age (P = 0.03) and eye-wall stress (P < 0.01) in the patients who developed glaucoma. 相似文献
74.
75.
Chaim Kaplinsky Celia Mor Yacov Goshen Isaac Yaniv Hanah Tamary Lutfi Jaber Batia Stark S. Stern Rina Zaizov Ian J. Cohen 《Pediatric hematology and oncology》1992,9(3):261-268
Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively. 相似文献
76.
77.
Lorraine D. Buckberry Ian S. Blagbrough Barrie W. Bycroft P.Nicholas Shaw 《Toxicology letters》1992,60(3):241-246
The C-S lyase enzymes are responsible for the generation of mutagenic and cytotoxic metabolites via aberrant drug-metabolising pathways in mammalian tissues. We have examined human hepatic cytosolic, mitochondrial and microsomal fractions for evidence of C-S lyase activity. The cytosolic enzyme was purified using fast protein liquid chromatography over FFQ Sepharose, Mono P and Superose 12. An homogeneous protein (monitored by SDS-PAGE) was obtained following purification, and an 11-fold increase in C-S lyase specific activity was observed. The molecular weight of the enzyme was found to be 37 kDa in denaturing conditions, 82.3 kDa in non-denaturing conditions, and the C-S lyase activity was shown to co-purify with kynurenine aminotransferase activity when the transaminase activity of the enzyme was examined with kynurenine as the substrate. 相似文献
78.
Patrick P. A. Humphrey Gary Buell Ian Kennedy Baljit S. Khakh Anton D. Michel Annmarie Surprenant Derek J. Trezise 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(6):585-596
Significant advances in understanding of P2X purinoceptor pharmacology have been made in the last few years. The limitations of nucleotide agonists as drug tools have now been amply demonstrated. Fortunately, inhibitors of the degrading ecto-ATPase enzymes are becoming available and it has become apparent that the complete removal of all divalent cations can be used experimentally in some systems to prevent nucleotide breakdown. Despite these issues, convincing evidence for P2X receptor heterogeneity, from data with agonists, has recently been reported.A number of new antagonists at P2X purinoceptors have also recently been described which to some degree appear to be more specific and useful than earlier antagonists like suramin. It is now apparent that suramin is a poor antagonist of ATP in many tissues because it potently inhibits ATPase activity at similar concentrations to those at which it blocks the P2X purinoceptor.Advances in the use of radiolabelled nucleotides as radioligands for binding studies has allowed the demonstration of P2X purinoceptors in a variety of tissues throughout the body including the brain. These studies have also provided evidence for receptor heterogeneity. Excitingly, two P2X purinoceptor genes have been cloned but operational studies suggest that more than two types exist. The cloning studies have also demonstrated a unique structure for the P2X purinoceptor which differentiates it from all other ligand-gated ion channel receptors. Further studies on P2X purinoceptor operation and structure are needed to help resolve controversies alluded to regarding the characterization and classification of nucleotide receptors. Hopefully such studies will also lead to a better understanding of the physiological and pathological importance of ATP and its activation of P2X purinoceptors. This will require the identification of better drug tools, in particular antagonists which may also provide the basis for novel therapeutic agents. 相似文献
79.
Vijay Tumuluri Graham A. Thomas Ian S. Fraser 《Journal of oral pathology & medicine》2004,33(4):204-208
BACKGROUND: We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS: Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm(2) of epithelium. RESULTS: Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 +/- 905 vs. 1908 +/- 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 +/- 650 vs. 1966 +/- 881; P < 0.0001). CONCLUSIONS: Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival. 相似文献
80.