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981.
All patients with adenocarcinoma of the colon treated surgically at the Austin Hospital over a five-year period were reviewed to determine the relevance of anaemia in diagnosis. It was found that one-fifth of the patients presented with symptoms of anaemia to the doctor of first contact, and of these, one-third had an unwarranted delay in diagnosis (mean delay 13 months). 相似文献
982.
A rapid, enzymatic assay for the measurement of inorganic pyrophosphate in animal tissues 总被引:2,自引:0,他引:2
A simple, rapid enzymatic assay for the determination of inorganic pyrophosphate in tissue and plasma has been developed using the enzyme pyrophosphate--fructose-6-phosphate 1-phosphotransferase (EC 2.7.1.90) which was purified from extracts of Propionibacterium shermanii. The enzyme phosphorylates fructose-6-phosphate to produce fructose-1,6-bisphosphate using inorganic pyrophosphate as the phosphate donor. The utilization of inorganic pyrophosphate is measured by coupling the production of fructose-1,6-bisphosphate with the oxidation of NADH using fructose-bisphosphate aldolase (EC 4.1.2.13), triosephosphate isomerase (EC 5.3.1.1), and glycerol-3-phosphate dehydrogenase (NAD+)(EC 1.1.1.8). The assay is completed in less than 5 min and is not affected by any of the components of tissue or plasma extracts. The recovery of pyrophosphate added to frozen tissue powder was 97 +/- 1% (n = 4). In this assay the change in absorbance is linearly related to the concentration of inorganic pyrophosphate over the curvette concentration range of 0.1 microM to 0.1 mM. 相似文献
983.
Two independent studies have compared killed C. parvum (CP) vaccine with viable BCG (Pasteur) and BCG (Glaxo) vaccines, respectively, for potentiation of antitumor immunity when injected with irradiated tumor cells into B6D2F1 AND CBA-T6T6 mice. Both studies concurred that, for a given number of irradiated tumor cells, larger amounts (dry weight equivalent) of BCG than CP were required to produce similar degrees of tumor immunity. Evidence also showed that stronger and more protracted immunity was mediated by CP than by BCG. 相似文献
984.
A model for building heat loss that includes hourly variation in solar radiation and windspeed was designed for use in evaluating solar heating system performance. Numerical simulations were run to see if, from an economic standpoint, the two effects were sufficiently large that a different solar collector size would be chosen than that selected using a heat loss model incorporating temperature only. The results show that solar system performance for the two models is significantly different on a daily basis but similar on a long term basis due to compensating factors. Thus, the simple model is adequate for selecting the optimum size of a solar collector. 相似文献
985.
Describes the development of the Paired Anxiety and Depression Scale which measures the relative balance between depression and anxiety but does not yield a quantitative measure of either. Results from undergraduates show that the amount of variance accounted for by the new scale was much greater than the Profile of Mood States and that all differences between Ss instructed to respond as "very depressed" or "very anxious" were significant. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
Two types of mechanosensitive units were found in the parenchyma of the rat mammary gland (SA and RA). Most of SA units had a spontaneous activity 1-3/sec. and responded to an abrupt displacement with a decline in the activity for 5-10 sec. RA had no such a response. The relation between average firing rate and displacement velocity at a constant displacement amplitude was linear for both SA and RA. RA however had the velocity threshold higher than SA. The number and frequency of SA afferent impulses decreased at a repeated stimulation. Electron microscopy revealed that free nerve endings correspond to SA and RA. 相似文献
987.
Using the context of pupil-initiated questions, selected verbal and nonverbal behaviors of teachers were investigated. 12 secondary school teachers in individualized classroom settings were asked to select 4 students subsequently labeled accepted, concerned, indifferent, and rejected. Teacher verbal behaviors were recorded with the Observation Schedule and Record 5V. Teacher–pupil interpersonal distance was recorded with the kinesthetic scale of the proxemic notation system (E. T. Hall, 1963). The 44 pupils selected completed the Describe Your School Inventory, a measure of pupil attitudes. Results show that school attitudes differed significantly between pupils labeled accepted, concerned, indifferent, and rejected. No significant differences were found in teacher behaviors toward these pupil groups. The usefulness of the situational context approach to the investigation of teacher behaviors is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
988.
Mark R. Hatswell W.Roy Jackson Francis P. Larkins Marc Marshall Douglas Rash Donald E. Rogers 《Fuel》1983,62(3):336-341
Some of the inherent cations of Victorian brown coals have been exchanged for iron by treatment with solutions of iron salts. Coals with various iron contents are obtained by variation of the pH of the solutions used. Hydrogenation of coals treated in this way at 395 °C, and an initial hydrogen pressure of 10 MPa, give product yields similar to those obtained using commercial cobalt molybdate on alumina catalysts, and greater than those obtained using red mud as a catalyst. The increase in yields compared with non-catalysed experiments results mainly from increased production of asphaltenes. The amount and composition of gas (80–90 wt% C02, resulting from decarboxylation) remains constant. Despite the similar conversions, the hydrogen consumption and tetralin/naphthalene ratios for iron-catalysed experiments are less than for cobalt—molybdate-catalysed experiments. 相似文献
989.
Investigated previous findings which suggest that a patterned masking stimulus, presented immediately following tachistoscopic presentation of letter rows, produces large decrements in the recall of letters from the central positions in the rows but has little effect on recall from either end of the displays. 4 experiments with 92 undergraduate Ss confirm the existence of a selective masking effect. The effect was obtained following exposure durations which varied from 30-200 msec. and with both full- and partial-report techniques. Also the selective masking effect was limited to multiletter displays in that it was shown that single letters were masked equally well across the positions used for an entire row. Results suggest that both ends of multiletter displays are processed and identified before the center positions of the displays are processed. (French summary) (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
990.
Side-effects of high pressure irrigation 总被引:1,自引:0,他引:1
CB Wheeler GT Rodeheaver JG Thacker MT Edgerton RF Edilich 《Canadian Metallurgical Quarterly》1976,143(5):775-778
This study was undertaken to identify side-effects of high pressure irrigation. Standardized surgical wounds made in Yorkshire pigs were subjected to high pressure syringe and pulsatile irrigation. As a result of these treatments, fluids were disseminated into the adjacent tissue of the wound, predominantly in a lateral direction. Bacteria did not accompany this disseminated fluid and apparently were filtered out by the surface tissues. This treatment results in a tissue injury which impairs its defenses, making the wound more susceptible to infection. However, the remarkable cleansing capacity of high pressure irrigation appears to outweigh this side-effect, since heavily contaminated wounds subjected to this treatment heal per primum without infection. 相似文献