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991.
Over the last decade, it has become evident that homologous transfusions carry immunologic consequences beyond the well-understood ones of alloimmunization to blood cell antigens. Transfusions constitute temporary transplants of large amounts of allogeneic antigen given intravenously and cause down-regulation of many cellular immune functions. These changes may explain in part the association of transfusion with such clinically important events as (1) improved survival of renal allografts, (2) decreased recurrence rates for autoimmune disease, (3) increased frequency and earlier recurrences of solid tumors, (4) increased frequency of post-operative bacterial infection, and (5) increased severity of viral infection. Preliminary data suggest that, in animal models and clinical settings, syngeneic or autologous transfusions are not associated with such events. This finding supports the hypothesis that these associations are cause and effect and involve immunologic mechanisms. 相似文献
992.
A I Ba?do N V Shiriaeva V I Khichenko P N Liuboslavskaia M V Starostina 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(6):645-646
Male rats of the strains with low (LE) high excitability (HE) of the nervous system have been used in this study. Half of the animals of each strain were neurotized in accordance with the Hecht's scheme. In the hippocampal slices of the non-neurotized LE rats there was a significant increase of the populational spike amplitude during development of LTP as compared with the opposite group of the animals. The LTP formation in the LE strain of rats caused a decrease in the S-100 protein content in the water-soluble, and an increase in the membrane-bound fraction of the protein. Similar results we have observed with the non-inbred Wistar rats but not with the HE strain of the animals. The levels of the water-soluble S-100 protein fraction were also higher in the hippocampuses and entorenal cortices, but not in the cerebellae of the LE strain, as compared with the HE strain of the rats. No differences have been found in the membrane-bound fraction of S-100 protein. 相似文献
993.
994.
The high cost of inpatient hospitalization and the rise in the number of private psychiatric beds for children and adolescents prompt several questions about who is using these services. To examine these issues, a review focusing on the use of psychiatric inpatient services by children was undertaken. The history of inpatient care of children is briefly outlined, recent public policies contributing to the rise in the number of psychiatric beds are considered, and findings from available studies are reviewed. We conclude that the data base is inadequate to draw many conclusions about who is using child psychiatric inpatient services. There appear, however, to be important differences in use of inpatient services according to age and perhaps by institutional type and geographic region. Suggestions for future research and some of the social policy implications are discussed as well. 相似文献
995.
Type IV collagenase activity was previously identified and purified to 7500-fold in homogenates from murine Walker 256 carcinoma, using acetylated [3H]-type IV collagen as a substrate. Anthracycline antibiotics daunorubicin, doxorubicin and epirubicin exhibited a non-competitive, reversible inhibition with Ki 92, 49 and 40 microM, respectively. This inhibitory effect, at therapeutically attainable concentrations of the forementioned antineoplastic drugs, may contribute, at least in part, to their antimetastatic properties. The anthracycline derivatives: 4-demethoxydaunorubicin, 4'-iododoxorubicin and 4-demethoxy-3'-deamino-3'-hydroxyepirubicin were without inhibitory effects at comparable concentrations. Other antineoplastic agents, such as belomycin, carmustine, cisplatine, etoposide, methotrexate, mitotane and teniposide did not exhibit any inhibitory effect at concentrations up to 1.0 mM. 相似文献
996.
997.
DNA 5' to the human myelin basic protein (MBP) gene, mapped to 18q22----qter, is known to manifest multiallelic DNA length variation with heterozygosity of at least 45%. Isolation of genomic DNA containing the MBP gene first exon and its 5' flanking region reveals that this polymorphism arises from a 994-bp region of the diverged tandem repeat (TGGA)249. This sequence is located from 1082 to 2075 bp upstream of the MBP initiator methionine. The repetitive sequence is 18% diverged from (TGGA)249 and from analysis of higher order subsequence reiterations appears to have undergone extensive recombination. The pattern of higher order repetition suggests that multiple crossover and gene conversion events have occurred within a 1.0-kb region. Molecular clones of this sequence represent essentially the longest allelic form of this region seen in Southern transfer analysis. This repetitive DNA is similar to a sequence 5' to the human myoglobin gene. 相似文献
998.
999.
M. J. Schwarz M. Super C. Wallis P. Beighton C. Newton L. E. Heptinstall C. Summers A. Markham G. Hambleton K. W. Webb D. Bilto D. Heaf M. Dalzell 《Human genetics》1990,85(4):428-430
Summary Details of haplotype and ΔF508 status from various populations represented in the cystic fibrosis (CF) DNA bank of the Royal
Manchester Children's Hospital are provided, together with information on the association of genotype and clinical status.
Clinical details and DNA analyses from native English in the North-West and South-West of England (Bath), from Lancashire
Pakistani families and from Afrikaans Namibian families are compared. A 78.5% incidence of ΔF508 has been found in English
families. Compound heterozygotes with CF and only one ΔF508 gene have an increased likelihood of having milder disease, with
lessPseudomonas isolated from sputum and relatively more showing either no regular respiratory pathogens or colonisation withStaphylococcus. There is also a relative increase in meconium ileus in these compound heterozygotes. The diagnosis of CF may be in doubt
in some subjects negative for ΔF508. Some of the Bath families have unusual haplotypes for an English population and a compound
heterozygote ΔF508/ΔI507 has been found. There is evidence from metD analysis of the founder effect in the Afrikaans Namibian
families, who have a high ΔF508 incidence. 相似文献
1000.
Gerard A. Kennedy Grahame J. Coleman Stuart M. Armstrong 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1990,166(5):607-618
Summary The effects of restricted feeding schedules on the circadian rhythms of wheel-running of Dasyurus viverrinus were examined under a light/dark cycle and in constant darkness (experiment 1) and in constant light (experiment 2). The results of the 2 experiments showed that: (1) in contrast to the light/dark cycle, restricted feeding is only a weak zeitgeber for the wheel-running activity rhythms of D. viverrinus; (2) restricted feeding elicits meal anticipatory activity in D. viverrinus comparable to that elicited by restricted feeding in the rat; (3) transient cycles of the anticipatory activity free-run with a period different to that of the main component of activity for several cycles after the termination of restricted feeding; and (4) activity suggestive of beating between 2 oscillators occurs during restricted feeding and after the termination of restricted feeding. Taken together the latter 3 observations suggest that the activity rhythms of D. viverrinus are controlled by at least 2 separate circadian oscillators. 相似文献