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61.
62.
Jeffrey E. Fletcher Florence J. Huggins Henry Rosenberg 《Journal canadien d'anesthésie》1990,37(6):695-698
Intracellular Ca++ levels in skeletal muscle are elevated during the in vitro contracture response of muscle from subjects with malignant hyperthermia. The role of Ca++ in the bathing medium and the consequences of substitution of Sr++ for Ca++ in the response to agents associated with malignant hyperthermia were examined. When Ca++ was omitted from the bathing medium the contractures induced in human vastus lateralis by halothane (three per cent) or succinylcholine (50 mM) were reduced by 80 and 100 per cent, respectively, while contractures induced by caffeine (8 mM) were only reduced by 50 per cent. Substitution of Ca++ by another divalent cation, Sr++, completely restored contractures induced by caffeine, but only partially restored contractures induced by halothane or succinylcholine (to 50 and 30 per cent of Ca(++)-containing medium, respectively). Mepacrine (10 microM) was effective in antagonizing contractures by caffeine, whereas verapamil and nifedipine (10 microM) were not. These results support an essential role for extracellular Ca++ not fulfilled by Sr++ in contracture induction by halothane and succinylcholine, but not by caffeine. 相似文献
63.
E M Burton D R Kirks J L Strife G C Henry J G Kereiakes 《AJR. American journal of roentgenology》1988,151(5):999-1002
A new low-dose chest radiographic system for use in the neonatal nursery was evaluated. This test system, composed of a Du Pont Kevlar fiber-front cassette, Quanta fast-detail screen, Cronex 4L film (wide latitude), and additional yttrium filtration (0.1 mm), reduced the radiation dose in neonatal chest radiography by 69% (0.9 vs 2.9 mrad [0.009 vs 0.029 mGy]) as compared with a conventional system without added yttrium filtration; the thyroid dose was reduced by 76% (0.9 vs 3.7 mrad [0.009 vs 0.037 mGy]). The cumulative dose reduction was achieved through a combination of factors, including (1) beam hardening by the added yttrium filter, (2) increased X-ray transmission through the Kevlar cassette, and (3) a fast film-screen combination. Scatter radiation at distances of 1 and 6 ft. (0.3 and 1.8 m) was negligible for both systems. Image sharpness was compared for the conventional system with and without added yttrium filtration and for the Kevlar system with yttrium. Although sharpness of bony detail was unchanged by adding yttrium filtration to the conventional system, a decrease in sharpness was noted with the Kevlar system. Because image sharpness was affected in the test system, we are not using the Kevlar-Cronex 4L system for mobile chest radiography in the neonatal intensive care unit, despite dose reductions. However, further study is recommended to determine if there is a slower film-screen combination with yttrium filtration that will not degrade image sharpness. 相似文献
64.
D A Cottrell M L Henry T M O'Dorisio R J Tesi R M Ferguson K Osei 《Diabetic medicine》1992,9(5):438-443
We have previously shown that the loss of acute first phase insulin secretion precedes pancreas allograft rejection and development of glucose intolerance in Type 1 diabetic patients. In order to examine whether there is a progressive loss of phases of insulin secretion and beta-cell function in technically successful pancreas transplants during the first year, we measured glucose, insulin, and C-peptide responses to physiological (mixed meal) and pharmacological (IV glucose and IV glucagon) stimulation in 27 glucose-tolerant, insulin-independent allograft recipients at 3, 6, and 12 months. Mean +/- SE fasting serum glucose levels were normalized throughout the study period. Postprandial serum glucose profiles tended to increase by 12 months compared to 3 and 6 months, although peak glucose levels were not statistically different. Following pancreas transplantation, basal serum insulin levels were high at 3 months (163 +/- 17 pM), 6 months (165 +/- 22 pM), and 12 months (248 +/- 54 pM, p = NS) in the Type 1 diabetic pancreas allograft recipients when compared to normal (25 +/- 3 pM). We observed slight elevations in postprandial insulin and C-peptide profiles at 12 months compared to 3 and 6 months. Following IV glucose and glucagon stimulation, serum insulin and C-peptide levels as well as phases of insulin release did not differ over the 12-month study period. Similarly, the glucose decay constant (KG) was nearly identical at 3, 6, and 12 months. In summary, 1 year following successful whole cadaveric, heterotopic pancreas transplantation in Type 1 diabetic recipients, fasting serum glucose remains normalized, while postprandial glucose tends to rise.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
A questionnaire that asked about policies concerning the use of human immunodeficiency virus (HIV) antibody tests was sent in January 1987 to the 200 hospitals in the United States that conduct infectious disease (ID) fellowship training (US ID hospitals) and to all 171 short-term-care Minnesota hospitals. Information was received from 189 of the US ID hospitals (94.5%) and from 160 (94%) of the Minnesota hospitals. Only 49% of the US ID hospitals and 37% of the Minnesota hospitals had an HIV antibody test-ordering policy; 47% of the US ID hospitals and 39% of the Minnesota hospitals had a specific educational program for physicians about the HIV antibody test; and 62% of the US ID hospitals and 41% of the Minnesota hospitals had an HIV autopsy policy. Marked variety existed in approaches to handling test results, obtaining patient consent, and providing risk-reduction information among the hospitals surveyed. These data suggest the need for a consensus on optimal use of HIV antibody testing at hospitals. 相似文献
66.
67.
The cytotoxic activity profile of an immunotoxin, SWA11-ricin A chain, recognising a cell-surface antigen associated with human small cell lung cancer (SCLC), was examined in detail using a panel of SCLC, non-SCLC and non lung tumour cell lines in tissue culture. SWA11-ricin A chain was potently and selectively active against three SCLC cell lines of both classic and variant morphologies, inhibiting the incorporation of 3H-leucine with an IC50 of 5 x 10(-11) M. At a concentration of 1 x 10(-8) M, the SWA11 immunotoxin could selectively eliminate in excess of 99.9% of clonogenic tumour cells. Intoxication proceeded rapidly following a 4 h lag phase; the initial rate of protein synthesis inhibition occurred with a t50 of 2 h and a t10 of 7 h. The cytotoxic activity of SWA11-ricin A chain was potentiated by 100-fold in the presence of the carboxylic ionophore monensin at 1 x 10(-7) M. Kinetic studies revealed that monensin enhanced the rate of protein synthesis inhibition by two-fold and eliminated the lag phase suggesting a rapid effect on either the rate or route of internalisation. Studies with SWA11 could detect no influence of monensin on the rate of antibody internalisation and a transient delay in the delivery of internalised antibody to lysosomes was observed by immunoelectron microscopy. 相似文献
68.
Extra-cellular recordings from single cells in the dorsal lateral geniculate nucleus (dLGN) of the tammar wallaby, Macropus eugenii, were made to find out whether the stratification of the nucleus could be correlated with the receptive field properties of units. Retinofugal fibres terminate in the lateral geniculate nucleus of the wallaby in nine interleaved eye-specific layers. These may be grouped into a lateral alpha segment of six laminae and a medial beta segment of three, in which the cells are less densely packed. Ninety percent of the geniculate neurons recorded from in the alpha segment gave brisk responses to stimulation of their receptive fields. Cells with sluggish responses predominated in the beta segment, but there was also a sizable minority of cells with brisk responses that were indistinguishable from those recorded in the alpha segment. In contrast, other response properties were rarely differentiated in individual layers. Thus, in most layers, the numbers of cells with transient or sustained responses were not significantly different, and this was also true for cells with ON- or OFF- responses. For each of these response pairings, however, the numbers of one type (ON- and transient) predominated in every layer. The accumulation of this laminar distinction lead to significant differences in the alpha and beta segments and in the nucleus as a whole. We conclude that cells in the individual layers of the dLGN of the tammar wallaby show no evidence of having receptive field properties in common that might correlate with separate functional streams. There is a functional segregation of receptive field properties between the alpha and beta segments. The organization of these two segments resembles that of the A and the C layers of the dLGN in cats and, possibly, the magnocellular and koniocellular components of the dLGN in primates. These broad similarities in functional partition of the dLGN of different species suggests that this aspect of the organization of the nucleus is independent of lifestyle. 相似文献
69.
70.
Ann M Henry Cathy Wilkinson James P Wylie John P Logue Pat Price Vincent S Khoo 《Radiotherapy and oncology》2004,73(1):57-59
On-line imaging of prostate markers can be used to compensate for errors in radiation delivery. This study assessed the patient acceptability and morbidity associated with the trans-perineal route of implantation. A minority experienced acute pain or bleeding. Placement was accurate in all but one subject. An operator related learning curve exists. Although this is an invasive procedure most patients found it acceptable. Implementation for routine clinical practice is feasible. 相似文献