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41.
E Zanelli TW Huizinga PA Guerne TL Vischer JM Tiercy W Verduyn GM Schreuder FC Breedveld RR de Vries 《Canadian Metallurgical Quarterly》1998,48(6):394-401
A family with 1 case of retinitis pigmentosa (III-1) and 2 cases of Oguchi's disease (III-2, 3) was examined in terms of electrophysiology as well as molecular biology. The proband (III-3), a 42-year-old female, and 2 older brothers (III-1, 2, aged 52 and 45 years) and 2 unaffected members in the same family participated in this study. Corrected visual acuities of the individuals with Oguchi's disease (III-2, 3) were 1.2. On funduscopy, blood vessels stood out in relief against a metallic-appearing background and a Mizuo-Nakamura phenomenon was evident. Full-field electroretinograms (ERGs) recorded from the proband were indicative of rod dystrophy, but results of other electrophysiological examinations (multifocal ERG, pattern ERG and visual-evoked cortical potential recordings) were within normal limits. Patient III-1 had corrected visual acuities of RE 20 cm/m.m. and LE 30 cm/n.d., severe chorioretinal atrophy in both fundi, and full-field ERG revealed rod-cone dystrophy. Mutation of the arrestin gene (1147de1A) was detected in all 3 patients. Visual function in each patient coincides with that of retinitis pigmentosa or Oguchi's disease, respectively. 相似文献
42.
The Eysenck Personality Profiler (EPP), a set of 21 scales measuring primary traits hypothesized to be definers of Neuroticism, Extraversion, and Psychoticism factors, was administered to 229 adults together with the Eysenck Personality Questionnaire--Revised (H. J. Eysenck & S. B. G. Eysenck, 1991) and the Revised NEO Personality Inventory (NEO-PI-R; P. T. Costa & R. R. McCrae, 1992b). Correlations of EPP scales with NEO-PI-R facet scales provided preliminary evidence supporting the convergent and discriminant validity of the EPP scales. However, varimax and targeted validimax factor analyses suggested that some EPP scales were misclassified and that EPP scales could better be understood in terms of the 5-factor model than the intended 3-factor model. 相似文献
43.
JA Teresi RR Golden P Cross B Gurland M Kleinman D Wilder 《Canadian Metallurgical Quarterly》1995,48(4):473-483
A study of item bias in standard cognitive screening measures was conducted in a sample of Afro-American, Hispanic and non-Hispanic white elderly respondents who were part of a dementia case registry study. The methods of item-response theory were applied to identify biased items. Both cross-cultural and high and low education groups were examined to determine which items were biased. Out of 50 cognitive items examined from six widely used cognitive screening measures, 16 were identified as biased for either high and low education groups or ethnic/racial group membership. 相似文献
44.
45.
One way hospitals complicate themselves is by increasing the participation of clinical professionals and middle managers in making strategic decisions. Using a survey methodology this article investigates the relationships between the participation of clinical professionals (MDs and RNs) and middle managers with hospital costs, as well as the possible moderating effect of strategic complexity. 相似文献
46.
Adhesive interactions between leukocytes and endothelium are required for subsequent leukocyte extravasation toward inflammatory sites. Understanding the possible kinetic expression of vascular cell adhesion molecule-1 (VCAM-1) in the middle ear cavity during an inflammatory cascade in vivo may be important for clarifying local immunological responses in otitis media. Two inflammatory models were produced in the rat and involved acute middle ear mucosal and cutaneous inflammation induced after inoculation or intradermal injection of lipopolysaccharide (LPS). After intravenous injection of both 125I-labeled anti-VCAM-1 and 131I-labeled control monoclonal antibody (mAb), the kinetic expression of VCAM-1 in the middle ear and skin was assessed by local radionuclide uptake. The biodistribution of an 125I-labeled anti-VCAM-1 mAb as a potential detector of focal inflammation was examined in normal rats. Both inflammatory lesions were characterized by early and sustained (up to 24 h) expression of VCAM-1, with maximal expression at 4 h after LPS stimulation. The kinetics of VCAM-1 expression was similar among the middle ear mucosa or skin specimens studied and different stimulation methods. A similar biodistribution and clearance of radioactivity between 125I-labeled anti-VCAM-1 mAb and 131I- or 99mTc-labeled control mAb were observed. The present result suggest that functional VCAM-1 induced by LPS is expressed in both middle ear tissue and skin lesions and may play a role in the initial stage of inflammatory response produced. Although VCAM-1 upregulation is a very early event in the inflammatory cascade, 125I-labeled anti-VCAM-1 mAb may be useful for the early detection of focal inflammation in the middle ear. 相似文献
47.
Watson M.E. Chilla J.L.A. Rocca J.J. Kim J.-W. Lile D.L. Vogt T.J. Robinson G.Y. 《Quantum Electronics, IEEE Journal of》1995,31(2):254-260
We report modulation saturation and time response measurements on InGaAs-InGaP MQW modulators. The measurements yield a saturation intensity of (3.7±0.1) kW/cm2 for a 0-10 V swing and switching times between 10 and 90 ns, depending on the bias voltage and incident light intensity. The observed dependence indicates that field screening due to carrier build-up is the dominant physical mechanism determining both the speed and the saturation intensity. This conclusion is supported by results of theoretical calculations 相似文献
48.
R R Watson 《Progress in food & nutrition science》1988,12(2):189-209
Several major physiological changes or disease states occur more frequently in alcohol abusers or prolonged high users. These include: cancer, immunosuppression, and nutritional deficiencies. They interact with potential enhancement of cancer growth or survival. Clearly alcohol abuse yielding cirrhosis is associated with immunosuppression of cellular immune functions. Severe, prolonged ethanol consumption frequently is associated with one or more nutrient deficiency. Such deficiencies are more common when there are other major problems such as liver or pancreas damage and in prolonged alcohol abusers should influence the host defenses against pathogens and tumors. The amount and frequency of nutritional and immunological deficiencies with "binge" or less severe alcohol abuse is less clear, but animal studies suggest they are frequently present. Clearly, nutrient deficiencies are common in alcohol abusers and could play significant roles in ethanol associated problems including immunosuppression. Data summarized suggest that immunosuppression caused by nutritional deficiencies and/or direct effects of ethanol and its' metabolites on lymphoid cells is a potential component of cancer in alcohol abusers. However the frequent occurrence of nutritional deficiencies, immunosuppression, and certain cancers in severe, prolonged ethanol abusers is an association, not proven cause and effect. 相似文献
49.
Ann-Kathrin Eichelmann George C. Mayne Karen Chiam Steven L. Due Isabell Bastian Frederike Butz Tingting Wang Pamela J. Sykes Nicholas J. Clemons David S. Liu Michael Z. Michael Christos S. Karapetis Richard Hummel David I. Watson Damian J. Hussey 《International journal of molecular sciences》2021,22(11)
TP53 gene mutations occur in 70% of oesophageal adenocarcinomas (OACs). Given the central role of p53 in controlling cellular response to therapy we investigated the role of mutant (mut-) p53 and SLC7A11 in a CRISPR-mediated JH-EsoAd1 TP53 knockout model. Response to 2 Gy irradiation, cisplatin, 5-FU, 4-hydroxytamoxifen, and endoxifen was assessed, followed by a TaqMan OpenArray qPCR screening for differences in miRNA expression. Knockout of mut-p53 resulted in increased chemo- and radioresistance (2 Gy survival fraction: 38% vs. 56%, p < 0.0001) and in altered miRNA expression levels. Target mRNA pathways analyses indicated several potential mechanisms of treatment resistance. SLC7A11 knockdown restored radiosensitivity (2 Gy SF: 46% vs. 73%; p = 0.0239), possibly via enhanced sensitivity to oxidative stress. Pathway analysis of the mRNA targets of differentially expressed miRNAs indicated potential involvement in several pathways associated with apoptosis, ribosomes, and p53 signaling pathways. The data suggest that mut-p53 in JH-EsoAd1, despite being classified as non-functional, has some function related to radio- and chemoresistance. The results also highlight the important role of SLC7A11 in cancer metabolism and redox balance and the influence of p53 on these processes. Inhibition of the SLC7A11-glutathione axis may represent a promising approach to overcome resistance associated with mut-p53. 相似文献
50.
Soil incubation studies were undertaken in controlled environment cabinets at 15°C to investigate the effect of increasing application rates of calcium ammonium nitrate (CAN) on net nitrification in two grassland soils. Granular CAN was applied to the surface of freshly collected, moist soil, at a rate equivalent to 0, 100, 200, 400, 800 and 1600µg NH
4
+
-N and NO
3
-
-N per gram of oven dry soil. In half the treatments finely ground CaCO3 was incorporated into the moist soil to raise the starting pH. Changes in soil mineral N and pH were measured at weekly intervals up to six-weeks. The most probable number (MPN) technique was used to enumerate the NH
4
+
-N and NO
2
-
-N oxidizers at the beginning and end of the incubation.At low rates of CAN application there was considerable NH
4
+
-N oxidation to NO
3
-
-N during the incubation of both soils. Lime stimulated this N transformation. At high application rates (i.e. 800 and 1600 ppm) there was little change in NH
4
+
-N or NO
3
-
-N on either soil during the 6 week incubation, in the presence or absence of lime. The rate of NO
3
-
-N produced peaked at 5.6 and 3.8 mg NO
3
-
-N kg–1 d–1 on soil 1 and 2 respectively, in the presence of lime. Above a level of 400 ppm CAN (equivalent to 38 kg N ha–1) the rate of NO
3
-
-N produced decreased. The higher rate of net nitrification in soil 1 compared with soil 2 was probably due to a higher number of nitrifying bacteria. Although high rates of CAN decreased the nitrifying activity of both soils there was little difference between treatments in the actual numbers of NH
4
+
-N and NO
2
-
-N oxidizers determined by the MPN technique.The results showed that the rate of granular CAN applied to the soil surface can influence the local activity of nitrifying bacteria and subsequent N transformations. At application rates of CAN generally used agriculturally for grass production, it is likely that net nitrification of the NH
4
+
-N in the fertilizer granule will be inhibited. 相似文献