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A partial human cDNA clone for the iron-protein (IP) subunit of succinate dehydrogenase (EC 1.3.99.1) was used in Southern analyses of restriction enzyme digests of genomic human and hamster DNA as well as hamster-human hybrids containing a limited number of human chromosomes. The gene for this protein was mapped to human chromosome 1. Digestion of genomic DNA with several restriction enzymes yielded two fragments detectable on a Southern blot, in contrast to the expectations based on the sequence of the cDNA clone. A preliminary analysis of a genomic clone with most of theIP gene has indicated the presence of several introns containing restriction sites detected by the Southern analysis. This genomic clone was also used for subregional mapping by fluorescence in situ hybridization (FISH) to human metaphase chromosomes. A single locus in the region 1p35-36.1 was identified.  相似文献   
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The study examined predictors of children's prosocial responses to adult negative emotions. An adult displayed anger, sadness and pain during play sessions with 39 preschoolers (mean age = 43 months). Older children responded more prosocially to all three emotions, whereas children with greater emotion knowledge responded more prosocially to the adult's sadness. Children who behaved prosocially in response to peers' negative emotions also were prosocial after the adult's negative emotions, even with effects of age and emotion knowledge held constant. Assertive children responded more prosocially to the adult's anger, even with effects of other variables held constant. Both theoretical and practical implications are discussed.  相似文献   
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Background: Inhibition of intestinal peristalsis is a major side effect of drugs used for anesthesia or for analgesia and sedation of patients in the intensive care unit. This in vitro study examined the effect of clonidine and dexmedetomidine on intestinal peristalsis and analyzed some of their mechanisms of action.

Methods: In isolated segments of the guinea pig small intestine, peristalsis was triggered by a perfusion-induced rise of the intraluminal pressure. The peristaltic pressure threshold to elicit a peristaltic wave was used to quantify drug effects on peristalsis. Vehicle (Tyrode's solution), clonidine (10 nm-100 [mu]m), or dexmedetomidine (0.1-100 nm) were added extraserosally to the organ bath. In other series of experiments, clonidine or dexmedetomidine was administered after pretreatment with yohimbine, prazosin, apamin, naloxone, or vehicle. Clonidine was also tested after blockade of NO synthase with l-NAME and in the presence of the inactive enantiomer d-NAME.

Results: Clonidine and dexmedetomidine concentration-dependently increased peristaltic pressure threshold and inhibited peristalsis (clonidine: EC50 = 19.6 [mu]m; dexmedetomidine: EC50 = 12.0 nm). The inhibition caused by clonidine could be prevented by pretreatment with yohimbine, naloxone, and apamin, but not by prazosin, l-NAME, or d-NAME. Inhibition caused by dexmedetomidine was prevented by yohimbine only.  相似文献   

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We have examined the patterns of expression of the major intermediate filament (IF) protein mRNAs during development of the hamster brain. Quantitative northern blotting was used to examine changes in the levels of mRNAs for the low, middle and high molecular weight neurofilament proteins (NF-L, NF-M, NF-H) as well as peripherin, vimentin and glial fibrillary acidic protein (GFAP). Total RNA was isolated from hamster brains at embryonic (E) days 12 and 14 and postnatal (P) days 1, 3, 5, 7, 9, 11, 13, 15, 20, 28 and 60-90 (adult), and probed with specific IF cDNAs. Northern blotting revealed that NF-L and NF-M mRNAs were present at very low levels in embryonic brain and that significant expression of these genes only occurred postnatally when the levels increased dramatically until P28 and then declined again in the adult. Increases in NF-H mRNA levels were somewhat delayed relative to those of NF-L and NF-M. NF-H mRNA was not seen at embryonic stages and was expressed at very low levels prior to P9; after that time the levels increased rapidly until P28 and then declined in the adult. Two of the type III IF genes, peripherin and vimentin, followed a pattern of expression opposite that of the NF genes. Both peripherin and vimentin mRNAs were present in embryonic brain and were expressed at higher levels during early postnatal stages than at later times. The magnitude and rate of reduction in vimentin gene expression in the postnatal interval was much greater than that of peripherin. GFAP mRNA levels were extremely low prior to P9 after which a robust increase occurred, followed by a decline in the adult. We discuss the implication of the dramatic changes in IF isotype expression in brain to the pathways of both neuronal and glial development in vivo.  相似文献   
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BACKGROUND: Automated component collection systems offer the possibility of increasing blood supply and improving transfusion safety. DESIGN: 30 blood donors were randomly assigned to double RBC collection with either the Baxter Alyx (AX), the Haemonetics MCS Plus (MCS+), or the Gambro Trima Accel (TA). Procedures were prospectively evaluated focussing on yield, time, efficiency, citrate donor load, and in vitro quality. RESULTS: All units showed sufficient in vitro quality throughout 42 days of storage and complied with international requirements. Donor reactions were limited to mild citrate reactions. AX was the fastest and most efficient system* * (* *p approximately 0.001) attaining the highest yield* * from similar amounts of whole blood. The drawbacks were a higher RBC loss* (*p < 0.05) and accelerated citrate infusion* *. Due to lower collection rates* * * (* * *p < 0.001), MCS+ was slower than TA* * * but compensated with lower citrate load * * *. CONCLUSION: Double RBC apheresis was performed safely and efficiently with all three instruments. AX had advantages for most parameters evaluated.  相似文献   
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