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931.
James H. McKillop John Wallwork Bruce A. Reitz Margaret E. Billingham Richard Miller I. Ross McDougall 《European journal of nuclear medicine and molecular imaging》1982,7(4):162-165
Lymphocytes separated from venous blood from six dogs who had heterotopic cardiac transplants have been labeled using 111In-oxine. Labeled lymphocytes were reinjected into the dogs and imaging of the heart carried out over the successive 3 or 4 days. For comparison serial ECGs and punch biopsies of the heart were obtained. Abnormal uptake of labeled lymphocytes in the donor heart was clearly visible in three of the six dogs, faintly visible in two and not seen in one. 630 Ci 111In was used in the dog where no uptake was seen and subsequent studies showed this amount of the radiopharmaceutical was toxic to lymphocytes. In the remaining five dogs the mean ratio of uptake of 111In in donor to recipient heart was 14:1 (range 6.5:1–21:1). The lack of substantial uptake in the transplanted heart of two dogs is attributed to a delay in rejection relative to the time the labeled lymphocytes were injected. The results suggest that 111In-labeled lymphocytes have potential as a noninvasive test for detecting rejection of cardiac transplants.J. McKillop is a Harkness Fellow of the Commonwealth FundJ. Wallwork is supported by National Heart Research Fund (UK) 相似文献
932.
Methods of controlling controlled substance (CS) inventories in unit dose dispensing systems vary. The two extremes are total floor stock of all CS drugs by the use of declining inventory signout sheets on the nursing unit to controlling only Class II and a few selected class III-V items. The method described herein outlines a systematic approach to controlling items on an individual patient basis consistant with the benefits of unit dose dispensing. A CS card assigned to each patient for each of his required controlled substance medications serves as an audit trail for doses consumed by the patient and provides a declining inventory receipt when returned to the pharmacy. 相似文献
933.
Establishment of a cell line from lepidopteran wing imaginal discs: Induction of newly synthesized proteins by 20-hydroxyecdysone 总被引:5,自引:0,他引:5
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Lynn DE Miller SG Oberlander H 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(8):2589-2593
A cell line has been developed from the imaginal wing discs of the lepidopteran insect Trichoplusia ni (Hübner). The cells grow in suspension as fluid-filled, multicellular vesicles. The cell line has been designated IAL-TND1. Two-dimensional electrophoresis (isoelectric focusing and sodium dodecyl sulfate/polyacrylamide gels) of [35S]methionine-labeled proteins revealed similar patterns for IAL-TND1 cells and whole T. ni wing imaginal discs. Additionally, exposure to the insect steroid hormone 20-hydroxyecdysone stimulated the synthesis of the same new proteins in both whole wing discs and IAL-TND1 cell vesicles. 相似文献
934.
Fuchs Robert P.P.; Lang Marie-Claude E.; Miller Elizabeth C.; Miller James A. 《Carcinogenesis》1981,2(7):655-659
Earlier studies showed that N-acetyl-2-aminofluorene (AAF) ismuch more carcinogenic than N-acetyl-2-amino-7-iodofluorene(AAIF). Subsequently it was found that substitution of C-8 ofguanine bases in DNA with AAF residues resulted in displacementof the guanine bases outside the DNA helix. This did not occurafter similar substitution with AAIF residues. As one approachto assessing the possible importance of this gross conformationaldifference to the carcinogenicity of AAF, the carcinogenic activitiesof two electrophilic esters, N-myristoyloxy-AAF and its 7-iododerivative, were compared by s.c. injection into male Fischerrats. On injection of a total of 64 µmol, each ester induceda high incidence of sarcomas, and the latent periods were similar.N-Myristoyloxy-AAIF was solvolyzed in aqueous media at aboutone-half the rate of N-myristoyloxy-AAF, and it was less than10% as reactive with native DNA as N-myristoyloxy-AAF. N-Myristoyloxy-AAFand N-myristoyloxy-AAIF were each less reactive than the correspondingacetoxy derivatives. These data suggest that the low carcinogenicityof AAIF as compared to that of AAF may not be associated withthe conformations of their adducts in the DNA. This differencein carcinogenicity may be related to differences in the ratesof metabolic activation and inactivation of these two amides. 相似文献
935.
936.
Salutario Martinez M.D. Carlisle L. Morgan Ph.D. M.D. John A. Gehweiler Jr. MD. Barry Powers M.D. Michael D. Miller M.D. 《Skeletal radiology》1979,3(4):206-212
Seven percent of 400 patients with cervical spine fractures and/or dislocations had unusual lesions of the axis. The authors have analyzed axis injuries by review of radiographs and clinical data and have derived a classification of traumatic conditions. Uncommon traumatic axis abnormalities are discussed with reference to incidence, causes, clinical findings, mechanism of injury, and roentgen characteristics.Picker Scholar, James Picker Foundation 相似文献
937.
D. C. German H. Harden M. K. Sanghera D. Mann R. S. Kiser H. H. Miller P. A. Shore 《Journal of neural transmission (Vienna, Austria : 1996)》1979,44(1-2):39-49
Summary The present study compares the effects of d-amphetamine (d-AMP) and the potent non-amphetamine CNS stimulant, amfonelic acid (AFA), on the firing rate of single midbrain dopaminergic (DA) neurons and on neostriatal DA metabolism (dihydroxyphenylacetic acid—DOPAC). The results indicate that AFA, like d-AMP, reduces the firing rate of DA neurons, although unlike d-AMP, AFA does not cause a decrease in neostriatal DOPAC content and, in fact, enhances that produced by haloperidol (HALO). The AFA-induced decrease in firing rate, like d-AMP, is reversed by the DA receptor blocker HALO, but again unlike d-AMP, the decrease in firing rate is not prevented by catecholamine synthesis inhibition with-methyl-para-tyrosine. Thus, both amphetamine and amfonelic acid have identical electrophysiological effects on DA neurons but act by different mechanisms. 相似文献
938.
During the past five years, there has been a sharp increase in the use of packed RBCs (PRBCs) and plasma products, whereas whole blood (WB) transfusions have steadily decreased. In order to determine whether plasma and its derivatives were being used to "reconstitute" whole blood from PRBCs, we performed a retrospective evaluation of all transfusion episodes in ten representative regional hospitals during a five-month period. Our results indicate that PRBCs were transfused 2.5 times more frequently than WB. Plasma products were administered with PRBCs less often than with WB: 14% of all PRBCs vs 24% of all WB units tranfused. The likelihood of a patient receiving plasma was found to correlate with the total amount of blood transfused and the frequency of transfusion. This study provides evidence that, at most, only a small percentage of PRBCs are given in conjunction with plasma as "reconstituted" WB. 相似文献
939.
940.
Novobiocin demonstrates an effect similar to that of probenecid (the "probenecid effect") in enhancing the therapeutic efficacy of antibiotics excreted mainly by the renal tubules. The ability of cefoxitin, cephalexin, cephalothin and penicillin G to protect mice against infection with Salmonella schottmuelleri was enhanced 2- to 3-fold when the animals were given oral doses of either probenecid or of novobiocin. The efficacy of cephaloridine, excreted mainly by glomerular filtration, was not enhanced by either probenecid or by novobiocin. 相似文献