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91.
The recent publication of Binary Alloy Phase Diagrams,2nd ed, [90Mas] and our extensive screening of phase diagram graphics
for this edition has revealed many phase diagram features, which while not explicitly violating phase diagram rules, are to
a lesser or greater extent unlikely to represent thermodynamically acceptable conditions. In two previous papers, several
thermodynamically improbable features or boundaries in binary phase diagrams were pointed out [91Oka2], and some unlikely
thermodynamic models were shown to be unrealistic, or in error [91Okal]. In the present paper, we discuss some of the unlikely
features in more detail in order to develop a set of guidelines that may be useful for checking future proposed phase diagram
boundaries, or some specific phase diagram features resulting from both experimental and theoretical work, including also
phase diagram assessments. 相似文献
92.
A 30-year-old man was referred as an acute case for keratitis. Two days earlier he had had photorefractive keratectomy for myopia at another clinic; a bandage contact lens was placed over the eye, but prophylactic antibiotics were not prescribed. The keratitis was treated with gentamicin sulfate (Garamycin) and chloramphenicol eyedrops. Scrapings from the cornea showed nonhemolytic streptococci. Two and a half months later, visual acuity was finger counting because of gross distortion of the corneal contour. The combination of a bandage contact lens and the lack of prophylactic antibiotics may have been the source of bacterial keratitis. 相似文献
93.
Cobra neurotoxin from Formosan cobra (Naja naja atra) venom is a compact globular protein having an intrinsic viscosity of 4.5 mL/g. The protein is stable in 7.5 M urea but can be denatured in 4.1 M guanidine hydrochloride or at elevated temperature (above 70 degrees C). Its conformation remains virtually the same in solvents of lower polarity than water such as 1,2-ethanediol or a mixed solvent of 1-propanol-1,2-ethanediol-water (5:1:1 by volume). The circular dichroism spectrum is "atypical" in water in that the peptide chromophores show a small negative circular dichroic (CD) band at 215 nm, a large positive one at 199 nm, and another large negative one below 190 nm. The CD pattern resembles to some extent that of a beta form but differs in both positions and magnitudes from the latter. It agrees qualitatively with the theoretical calculations of the reverse beta bends, suggesting that cobra toxin contains a considerable amount of beta turns and possibly a mixture of beta form and beta turns. 相似文献
94.
Gamma-hydroxybutyric acid (GHB) was orally administered to six alcoholics at 09.00 and 23.00 h. The plasma concentrations of GHB show a clear circadian pattern, the area under the curve in the daytime experiments being 61% of that in the night experiments. The significance of alcohol dehydrogenase, the catabolic enzyme of GHB, for the difference is discussed. It is concluded that, although the activity of alcohol dehydrogenase in alcoholics is quantitatively disturbed, it remains subject to physiologic circadian activation. 相似文献
95.
TB Hoeksema 《Canadian Metallurgical Quarterly》1995,33(5):289-294
Ways were delineated in which group home employees can support individuals living in the home in the active expression of faith, both inside and outside the group home environment, and at the same time protect the freedom of others in the home who choose not to be involved in religious activities. After briefly reviewing some assumptions underlying the 1992 AAMR definition of mental retardation and describing the capability of religious expression for individuals with cognitive impairment, we presented several guidelines to assist group home staff members. 相似文献
96.
Six healthy adult mares were given a single dose (25 mg/kg of body weight) of sodium oxacillin IM. Oxacillin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum oxacillin concentration was 9.75 microgram/ml at 0.5 hour after injection. Mean peak oxacillin concentrations in synovial and peritoneal fluids were 1.45 microgram/ml and 2.60 microgram/ml at 1 hour and 2 hours, respectively. These concentrations decreased in parallel with serum values and were not measurable at 48 hours. Urine concentrations of oxacillin were high, with a mean peak concentration of 2,790.2 microgram/ml at 0.5 hour. 相似文献
97.
98.
OBJECTIVE: To evaluate the effects of supraceliac and infrarenal aortic cross-clamping on the expression of neutrophil integrin in CD11b (a marker of systemic cytokine release). DESIGN: Two groups, determined by anatomic placement of aortic cross-clamp. Laboratory personnel were blinded as to group assignment. SETTING: University teaching and community hospitals. Laboratory facilities used were university and Veteran's Affairs medical centers. PARTICIPANTS: Patients scheduled for aortic surgery. INTERVENTIONS: Blood sampling was performed at baseline, after 30 minutes of aortic cross-clamp duration, 30 and 90 minutes after reperfusion (for tumor necrosis factor-alpha plasma levels in infrarenal cross-clamp group), and at baseline and 90 minutes reperfusion (for neutrophil CD11b expression quantification) in both groups. MEASUREMENTS AND MAIN RESULTS: Tumor necrosis factor-alpha measured by ELISA technique did not change at any time period in the infrarenal clamping group. Neutrophil CD11b expression, measured by double antibody staining and FACScan analysis, did not change significantly at 90 minutes of reperfusion in the infrarenal group, but increased significantly (p < 0.05) in the supraceliac aortic cross-clamp group. CONCLUSION: Neutrophil integrin CD11b has been demonstrated to be the primary adhesive glycoprotein responsible for neutrophil organ entrapment and subsequent neutrophil-mediated reperfusion injury. These results suggest that upregulation of neutrophil integrin CD11b after supraceliac aortic clamping may in part be responsible for the higher incidence of acute lung injury after thoracic aortic aneurysm repair requiring supraceliac clamping when compared with infrarenal aneurysm surgery. 相似文献
99.
EM Pinholt E Solheim O Talsnes TB Larsen G Bang OJ Kirkeby 《Canadian Metallurgical Quarterly》1994,33(2):193-197
The development of approaches to screening of hospital patients for harmful drinking frequently encounters resistance from both patients and hospital staff. A contributing factor could be the discomfort both feel about talking specifically about drinking. One approach to reducing this discomfort has been to mask concern about alcohol consumption into a general focus on other health and lifestyle issues. One-hundred and eighty-two patients admitted to an emergency department were presented randomly with either a straight alcohol screening questionnaire or a general health and lifestyle questionnaire with alcohol questions embedded amongst items on smoking exercise and diet. The number of returns was equal for both questionnaires which suggests the masked questionnaire does not improve the acceptability of alcohol screening in hospital environments. 相似文献
100.
TB Rosenzweig AM Palestrant CA Esplin RB Gilsdorf 《Canadian Metallurgical Quarterly》1994,168(6):587-90; discussion 590-1
BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) has been established as a faster and safer procedure than open surgical gastrostomy. It cannot be done, however, for many patients with partially obstructing pharyngeal or esophageal carcinoma, previous gastrectomy, upper abdominal surgery, or bowel distension from distal obstruction. PATIENTS AND METHODS: We attempted percutaneous radiologic-assisted gastrostomy (RAG) in 231 patients referred for gastrostomy, 38 of whom had a relative contraindication for PEG. The procedure involves passing, under radiologic guidance, an orogastric inflation tube that contains a snare. We used a 5-inch long, 18-gauge needle to transabdominally insert a wire into the stomach, avoiding loops of bowel visualized by air contrast. Retrieving the transabdominal wire by snare allowed retrograde passage of the gastrostomy tube as done in standard PEG. RESULTS: The procedure was successful in 230 of 231 cases, including 37 of the 38 patients with contraindications. We could not gain gastric access in 1 patient with a 75% gastrectomy. Overall, 6 patients developed complications and 1 died. There was no procedure-related morbidity or mortality in the patients with contraindications to PEG who underwent successful RAG. Subsequent laparotomy indicated tube passage through the liver in 2 of these cases and small bowel mesentery in 1 case without clinical problems. We performed a percutaneous jejunostomy in the efferent limb of the gastrojejunostomy in 1 patient with a previous gastrectomy. CONCLUSION: The snare technique is simpler and faster than the usual radiologic gastropexy technique, and safer than an endoscopic procedure. It has become our procedure of choice for gaining gastric access. 相似文献