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排序方式: 共有1646条查询结果,搜索用时 31 毫秒
11.
AW Jones 《Canadian Metallurgical Quarterly》1993,39(9):1837-1844
The concentration-time profiles of ethanol were determined for capillary blood, end-expired breath, and saliva after 21 healthy men ingested ethanol at 0.68 g/kg body weight. Near the time of obtaining body fluids, the volunteers estimated their feelings of intoxication, and body sway (with open and closed eyes), hand tremor, positional alcohol nystagmus (PAN), and roving ocular movements (ROM) were quantitatively recorded. The concentration-time profiles of ethanol in blood, breath, and saliva agreed well within individuals but there were large variations between subjects. The mean saliva-ethanol profiles ran slightly above those for blood and breath. Subjective ratings of intoxication and impairment of body function (standing steadiness and hand steadiness) were highest at the time of reaching the peak concentrations of ethanol in body fluids. PAN was evident in most subjects between 60 and 120 min after the start of drinking, whereas ROM appeared mainly during the postabsorptive phase of ethanol kinetics (120-420 min). The blood ethanol concentration thresholds were between 500 and 700 mg/L (50-70 mg/dL) when the diminished performance had recovered to baseline values. 相似文献
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Perchloric acid (70%) was used to create simulated periapical lesions in tooth sockets of 15 dentate cadaver jaw specimens. Using the Trophy USA direct digital radiographic system, linear images were captured at selected time intervals after initial acid application and altered by contrast reversal, pseudocolor enhancement, and two forms of histogram equalization. The 525 total images were randomized for display on a computer monitor for evaluation by five endodontists. Images were evaluated twice by each rater, with viewings 1 to 2 wk apart. Statistical analysis determined interrater variability, intrarater reproducibility, and the relative merits of each enhancement technique. At 8, 12, 16, and 24 h after acid application, both techniques of histogram equalization yielded a statistically significant improvement over reverse contrast in perception of periapical patholais. Linear and pseudocolor-enhanced images were also significantly more diagnostic than reverse contrast at 12, 16, and 24 h. Intrarater reproducibility showed moderate agreement, but analysis showed only a fair level of interrater agreement. 相似文献
14.
The microsomal enzyme glycosylphosphatidylinositol mannosyltransferase I (GPIMT-I) catalyses the transfer of a mannosyl residue from beta-mannosylphosphoryldolichol (beta-Man-P-Dol) to glucosamine-alpha(1,6)(acyl)phosphatidylinositol (GlcN-aPI) to form Man alpha(1,4)GlcN-aPI (ManGlcN-aPI), an intermediate in glycosylphosphatidylinositol (GPI) synthesis. While the transfer of [3H]mannosyl units to endogenous GlcN-aPI was not seen when membrane fractions from normal Chinese hamster ovary (CHO) K1 cells were incubated with exogenous [3H]Man-P-Dol, GPIMT-I activity could be characterized with an in vitro enzyme assay system employing membrane fractions from Lec15 or Lec35 cells. These CHO cell mutants apparently contain elevated levels of endogenous GlcN-aPI due to the inability to synthesize (Lec15) or utilize (Lec35) beta-Man-P-Dol in vivo. The presence of a saturated alpha-isoprene unit in the dolichyl moiety is required for optimal GPIMT-I activity since beta-mannosylphosphorylpolyprenol (beta-Man-P-Poly), which contains a fully unsaturated polyisoprenyl chain, was only 50% as effective as beta-[3H]Man-P-Dol as a mannosyl donor. When beta-[3H]-Man-P-Dol and alpha-[3H]Man-P-Dol were compared as substrates, GPIMT-I exhibited a strict stereospecificity for the mannolipid containing the beta-mannosyl-phosphoryl linkage. beta-[3H]Man-P-dolichols containing 11 or 19 isoprenyl units were equally effective substrates for GPIMT-I. Membrane fractions from Lec 9, a CHO mutant that apparently lacks polyprenol reductase activity and synthesizes very little beta-Man-P-Dol, but accumulates beta-Man-P-Poly, synthesized no detectable Man-GlcN-aPI when incubated with beta-[3H]Man-P-Dol in vitro. This indirect assay suggests that GlcN-aPI does not accumulate in Lec 9 cells, possibly because it is mannosylated via beta-Man-P-Poly, or perhaps the small amount of Man-P-Dol formed by the mutant in vivo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
15.
LM East CJ Savage JL Traub-Dargatz CE Dickinson RP Ellis 《Canadian Metallurgical Quarterly》1998,212(11):1751-1756
OBJECTIVE: To identify clinical signs, physical examination findings, results of diagnostic tests, treatments administered, and clinical outcome of neonatal foals with enterocolitis associated with Clostridium perfringens infection. DESIGN: Retrospective study. ANIMALS: 54 neonatal foals. RESULTS: Most foals had acute onset of obtunded mentation, colic, or diarrhea and developed leukopenia, neutropenia, an abnormally high number of band neutrophils, toxic WBC, and hypoproteinemia within 24 hours after admission, despite high serum IgG concentrations (> 800 mg/dl). Abdominocentesis and abdominal radiography of some foals revealed exudative peritonitis and gaseous distention of the small and large intestine, respectively. Cytologic examination of feces revealed spores or gram-positive rods in 8 of 10 foals. The most common genotypes of C perfringens isolates were type A and C, alone or in combination. Treatment did not alter mortality rate for most foals that had a positive culture for C perfringens type C. Of 54 foals, 29 (54%) that had C perfringens-associated enterocolitis died. Foals that had a culture that yielded C perfringens had higher sepsis scores, IgG concentrations, and mortality rates, compared with the overall hospital population of neonatal foals. CLINICAL IMPLICATIONS: Foals less than 7 days old that have enterocolitis associated with C perfringens infections, especially type C, have a guarded prognosis. Cytologic examination of feces to determine spore counts and detect rods may be a means for early identification of C perfringens infections. Polymerase chain reaction assays to determine genotype are important for designing preventive treatment regimens. 相似文献
16.
AN Salt MM Henson SL Gewalt AW Keating JE DeMott OW Henson 《Canadian Metallurgical Quarterly》1995,88(1-2):79-86
The experiments carried out on the model of immobilization stress permit establishing the antiulcer effect of preventive introduction of sodium succinate solution, milk serum solution and solution of milk serum with sodium succinate. A decrease in the degree and number of ulcers and in the integrative indices characterizing the ulcer process after introduction of the studied drugs was accompanied by a fall of the intensity of lipid peroxidation processes. 相似文献
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Schistosoma mansoni and S. japonicum infections in nude mice (nu/nu) were compared with infections in nu/+ heterozygotes or intact mice. Seven to 12 weeks after exposure to S. mansoni, the responses of Swiss NCR, C3H, BALB/c and C57B1/6 nude mice did not differ substantially. Nude mice of all these strains showed minute granulomas around eggs in the liver and minimal hepatic fibrosis. Microvesicular and necrotizing changes in hepatocytes were similar in all mouse strains, and S. mansoni infections were frequently lethal to nude, but not to intact mice between the seventh and ninth weeks of infection. Nude mice that survived the ninth week of infection generally lived until the 12th week. The number of eggs per mature worm pair in the tissues of S. mansoni-infected nude mice was similar to the number in intact mice, but nude mice passed fewer eggs in the feces. Nude mice that received serum from infected intact mice excreted eggs in the stool in numbers equivalent to intact mice, but continued to form minute granulomas around S. mansoni eggs. Reconstitution with fetal thymus or with splenocytes from normal or S. mansoni-infected mice partially or completely restored hepatic granuloma size, granuloma eosinophils, hepatic fibrosis, and excretion of eggs in the feces. In contrast to S. mansoni infection, S. japonicum infections in nude mice did not cause necrosis of hepatocytes or excessive mortality, and S. japonicum eggs were passed in the feces in numbers equivalent to those passed by infected intact mice. 相似文献
19.
TG Mackay D Georgiadis DG Grosset AW Kelman KR Lees DJ Wheatley 《Canadian Metallurgical Quarterly》1995,4(4):414-419
The application of transcranial Doppler (TCD) ultrasonography to asymptomatic prosthetic heart valve patients can result in detection of localized bursts of high intensity signals, similar to those caused by the passage of emboli. The origin of these signals is not known. In order to investigate this phenomenon in a simplified, more controllable environment, a TCD machine was used to record flow downstream from mechanical prosthetic heart valves in a mock circulatory loop. The model, which uses a saline solution seeded with silk particles (< 15 micrometers) as the circulatory fluid, recreates the principal hydrodynamic characteristics of the left heart and systemic circulation. Reproducibility of the system was established through repeated testing of a Monostrut valve. Three different mechanical valve types, (Monostrut, Medtronic Hall, St. Jude Medical) were tested over a range of simulated cardiac outputs, and the effect of valve size was investigated with four Omniscience tilting disc valves (21, 23, 25 and 29 mm). Average energy of the reflected Doppler signal was used to quantify the amount of high intensity Doppler signal, QTCD. TCD signals recorded in vitro were visually and aurally similar to those found in prosthetic heart valve patients. All valve types generated exponentially more QTCD with increasing simulated cardiac output. Differences amongst valve types were only significant at higher flow outputs, with the Monostrut valve producing the greatest QTCD. Larger valves consistently generated greater QTCD than smaller valves. In conclusion, TCD signals found in prosthetic heart valve patients can be reproduced, at least qualitatively, using a mock circulatory loop which does not incorporate the formed elements of blood.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
20.
AW Locher 《Canadian Metallurgical Quarterly》1996,25(6):465-469
The spread of human immunodeficiency virus (HIV) infection in women of childbearing age has precipitated discussion of the procreative rights of this population. Ethical principles are cited to support both sides of the argument. Implications for nursing care include the need to (1) examine one's own opinion on the issue, (b) assess the context in which the patient is making her decision, (c) share detailed information, and (d) create a supportive environment. 相似文献