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11.
Williamson Kathleen A.; Hever Ann M.; Rainger Joe; Rogers R. Curtis; Magee Alex; Fiedler Zdenek; Keng Wee Teik; Sharkey Freddie H.; McGill Niolette; Hill Clare J.; Schneider Adele; Messina Mario; Turnpenny Peter D.; Fantes Judy A.; van Heyningen Veronica; FitzPatrick David R. 《Human molecular genetics》2006,15(12):2030
Table 1 相似文献
12.
The cytoskeleton is susceptible to oxidative stress and this occurs prior to membrane blebbing and cell lysis. Vimentin intermediary filaments in rheumatoid synoviocytes are more susceptible than in normal synoviocytes and this may have pathological significance. They are however no more susceptible to heat shock than other cell types. 相似文献
13.
14.
Multiphase radon generation and transport in porous materials 总被引:5,自引:0,他引:5
Radon generation and transport in porous materials involve solid, liquid, and gas phases in the processes of emanation, diffusion, advection, absorption, and adsorption. Oversimplifications, such as representing moist soil systems by air-phase emanation and transport models, cause theoretical inconsistencies and biases in resulting calculations. Detailed Rn rate balance equations for solid, liquid, and gas phases were analyzed and combined using phase equilibrium constants to derive a single diffusive-advective rate balance equation in the traditional form. The emanation, diffusion, and permeability coefficients in the new equation have expanded definitions and interpretations to include Rn phase transfer. Radon adsorption was characterized by an exponential moisture dependence, and diffusion and permeability constants utilized previous moisture relationships. Correct boundary and interface conditions were defined, and the unified theoretical approach was applied to field data from a diffusion-dominated system and to laboratory data from an advection-dominated system. Measured 222Rn fluxes and concentrations validated the modeled values within the measurement variability in both applications. 相似文献
15.
D M Morris R Haskins A A Marino R P Misra S Rogers S Fronczak J A Albright 《Surgery》1990,107(6):627-631
Carbon in the form of 8-micron fibers induces growth of connective tissue. The purpose of this study was to measure and histologically characterize tissue ingrowth occurring in carbon fibers implanted for up to 12 months in abdominal-wall defects in rats, compared with polypropylene mesh. Carbon fibers induced significantly more tissue ingrowth than polypropylene mesh at 6 to 12 months postoperatively. The predominant tissues associated with carbon fibers and polypropylene mesh were dense connective tissue and fat, respectively. Fragmentation of the implants did not occur, and implant debris was not found in the regional lymph nodes. Carbon fibers are potentially useful for reinforcing abdominal-wall defects. 相似文献
16.
Regional cerebrovascular reactivity to carbon dioxide during cardiopulmonary bypass in patients with cerebrovascular disease 总被引:1,自引:0,他引:1
G P Gravlee R C Roy D A Stump A S Hudspeth A T Rogers D S Prough 《The Journal of thoracic and cardiovascular surgery》1990,99(6):1022-1029
In patients with cerebrovascular disease, hypercarbia may cause redistribution of regional cerebral blood flow from marginally perfused to well-perfused regions (intracerebral steal), as evidenced by regional cerebral blood flow studies during carotid endarterectomy. During hypothermic cardiopulmonary bypass, the pH-stat method of acid-base management produces relative hypercarbia. To determine whether pH-stat management produces relative hypercarbia. To determine whether pH-stat management induces intracerebral steals, we investigated nine patients with cerebrovascular disease undergoing coronary artery bypass grafting. During hypothermic cardiopulmonary bypass, arterial carbon dioxide tension was varied in random order between 40 mm Hg and 60 mm Hg (uncorrected for body temperature). Regional cerebral blood flow was measured by clearance of 133 xenon injected into the arterial inflow cannula. Nasopharyngeal temperature (26.8 degrees-28.0 degrees +/- 2.2 degrees-3.0 degrees C), perfusion flow rate (2.14-2.18 +/- 0.70-0.73 L/min/m2), mean arterial pressure (67-68 +/- 6-9 mm Hg), arterial carbon dioxide tension (302-308 +/- 109-113 mm Hg), and hematocrit (23% +/- 4%) were maintained within narrow limits in each patient during arterial carbon dioxide tension manipulation. Global mean cerebral blood flow values were similar to previously reported values in patients free of cerebrovascular disease; patients in this study averaged 15.2 +/- 2.5 ml/100 gm/min at an arterial carbon dioxide tension of 46.1 +/- 8.4 mm Hg and 25.3 +/- 6.1 ml/100 gm/min at an arterial carbon dioxide tension of 71.1 +/- 11.8 mm Hg. Carbon dioxide reactivity, defined as mean global cerebral blood flow (in ml/100 gm/min) divided by arterial carbon dioxide tension (in mm Hg), was similar in the region having the lowest regional cerebral blood flow and in the brain as a whole. No patient developed evidence of an intracerebral steal at the higher arterial carbon dioxide tension. During hypothermic cardiopulmonary bypass, higher levels of arterial carbon dioxide tension, such as those associated with the pH-stat management technique, are apparently not associated with potentially harmful redistribution of cerebral blood flow in patients with cerebrovascular disease. 相似文献
17.
A study of possible nutritional determinants of certain haemostatic factors (heparin-neutralizing activity, fibrinogen and antithrombin III) was conducted in the Caerphilly cohort of 2512 men. Data on diet were obtained in a sub-sample of 665 men by a 7-d weighed dietary inventory and in the complete cohort by questionnaire. All the associations between major nutrients and haemostatic factors were weak and few achieved statistical significance. There were significant associations between two of the blood tests and total energy intake which suggests that, in general, relationships between nutritional variables and thrombosis-related factors should be standardized for total energy intake. Negative associations between alcohol, fibrinogen and antithrombin III and positive associations between fibre, polyunsaturated fat and antithrombin III are of possible clinical or public health importance. However, nutritional factors appear to explain only about 3 per cent of the variance in the distributions of the haemostatic factors examined. The extent to which uncertainties in the measurement of dietary intake will have led to the underestimate of the true association is, of course, unknown. At the same time it is of relevance that in similar studies of dietary determinants of plasma cholesterol only about 3 per cent of the variance of cholesterol levels can be explained. 相似文献
18.
The sp act of galactose-1-phosphate uridyltransferase has been measured in individual regions of adult rat brain to see if site-specific differences in enzyme activity can aid in the understanding of brain abnormalities observed in well-treated galactosemic patients. The sp act in the cerebellum, brain stem, and midbrain were higher than in the cortex, hippocampus, and striatum. Activity in the cerebellum was 2-fold greater than that found in the cortex. Steady state levels of mRNA of the enzyme in the cerebellum were twice that of the cortex corresponding to the ratio of enzyme sp act in the two regions. Measurement of the kinetic parameters in tissue from the cerebellum and cortex revealed that the regional specificity in enzyme activity observed in the brain represents differences in the Vmax. Inhibition of the enzyme by uridine and uridine triphosphate was essentially the same for all regions and was not influenced by the 2-fold differences observed in the levels of enzyme. Inhibition by uridine was significantly greater than that for uridine triphosphate. 相似文献
19.
Haiyung Cheng Jules I. Schwartz Charles Lin Raju D. Amin James R. Seibold Kenneth C. Lasseter David L. Ebel Dominick J. Tocco J. Douglas Rogers 《Biopharmaceutics & drug disposition》1994,15(5):409-418
MK-679 (R(?)-3-((3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl)(3-(dimethylamino)-3-oxopropyl)thio)methyl)thio(propanoic acid) is a potent and specific LTD4-receptor antagonist. The disposition of MK-679 was investigated in a three-way crossover study in 12 healthy males receiving single intravenous doses of 75, 250, and 500 mg of MK-679. A greater than proportional increase in the area under the plasma concentration—time curve of MK-679 was observed with increase in dose. The plasma concentration data for each subject fitted well to the differential equations for a two-compartment model with linear tissue distribution and Michaelis-Menten elimination from the central compartment, indicating that the elimination of MK-679 in humans is saturable. In a previous study, the disposition of MK-679 in humans was also dose-dependent when given together with its S(+)-isomer, L-668,018. Thus, the disposition of MK-679 in humans is dose-dependent regardless of the presence of its stereoisomer. Also, the bioavailability of MK-679 was determined in six healthy males receiving simultaneously an oral dose of 250 mg of MK-679 and intravenous infusion of 1 mg 14C-MK-679. Results of this study indicate that the oral bioavailability of MK-679 is nearly quantitative. 相似文献
20.
J. O’Byrne S. Eustace M. M. Stephens M. N. M. R. Farahat G. Yanni R. Posten G. S. Panayi S. Sant R. Costello M. Barry J. Hassan C. Feighery B. Bresnihan A. Whelan F. Coakley A. M. de Paor R. B. Reilly E. B. Casey V. J. Tormey G. Kearns K. Gaffney P. J. Freyne M. Callaghan O. FitzGerald D. Veale E. O’Nuallain D. Reen D. Veale M. Farrell O. FitzGerald S. Rogers L. Barnes R. J. Coughlan C. McCarthy M. McDermott D. Hourihane C. O'Morain S. O'Reilly P. Hartley E. Casey L. Clancy F. Mulcahy N. Hall A. Murphy C. Breen D. Kelleher M. Abuzakouk C. O'Farrelly 《Irish journal of medical science》1992,161(6):438-442