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141.
In vitro and in vivo selectin-blocking activities of sulfated lipids and sulfated sialyl compounds 总被引:2,自引:0,他引:2
Mulligan MS; Warner RL; Lowe JB; Smith PL; Suzuki Y; Miyasaka M; Yamaguchi S; Ohta Y; Tsukada Y; Kiso M; Hasegawa A; Ward PA 《International immunology》1998,10(5):569-575
There is accumulating evidence that sulfated lipids, sulfated
oligosaccharides and other sulfated compounds are reactive with selectins
in a manner that interferes with selectin interactions with their natural
ligands. In the report we describe the ability of sulfated lipids
(sulfatides and gangliosides) and multimeric forms of sulfated sialic acid
to block binding of P- and E-selectin-Ig to neutrophils. The in vivo
ability of these compounds to block lung injury in rats following i.v.
infusion of purified cobra venom factor (CVF), which induces injury that is
L- and P-selectin dependent, was also determined as well as effects on
recruitment of neutrophils, as measured by lung myeloperoxidase. There was
a significant correlation between the ability of sulfated lipids and sialyl
compounds to interfere in vitro with P-selectin-Ig binding to neutrophils
and to protect against P-selectin-dependent acute lung injury induced by
CVF. The biological effects of these sulfated compounds were also
associated with diminished accumulation of neutrophils. The protective
effects of these compounds may be linked to their ability to interfere with
P- selectin binding to counter-receptors on neutrophils.
相似文献
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143.
Summary: A patient showing seizures presenting ictal automatisms with preserved consciousness is reported. A 30-year-old, right-handed man with normal development and without family history of epilepsy was referred for surgical treatment of epilepsy. At 15 he began to have seizures, starting with an epigastric aura, occasionally developing automatisms (lip-smacking, chewing), sometimes followed by tonicxAonic convulsions. At the time of referral, he averaged six convulsive seizures per year and one nonconvulsive per week. His sleep EEG showed sharpened slow activity over the right anterior quadrant magnetic resonance imaging (MRI) showed a benign lesion in the mesial aspect of the right occipital lobe. Simultaneous video monitoring and intracranial EEG with subdural strips recording from the right temporal and occipital lobes was undertaken. During one seizure, he had pronounced oroalimentary automatisms while holding a conversation with a technician, answering her questions, and explaining details of his seizures. Memory of this event was preserved. At seizure onset, spike activity was seen at the mesial occipital strips. At mid-seizure, high-voltage sharpened delta was seen throughout the right hemisphere. Left-sided scalp electrodes remained relatively uninvolved. The lesion, a dysembryoplastic neuroepithelial tumour was removed. Surgery was followed by abolition of seizures described. Because it is agreed that complex partial seizures require impaired consciousness, a history of automatisms with retained consciousness usually suggests nonepileptic attacks. This case suggests that automatisms in epileptic seizures can take place with minimal loss of consciousness, particularly if there is widespread but unilateral involvement. The need for a revision of the International Classification is suggested. 相似文献
144.
Background: The clutter of equipment and lines in today's operating room (O.R.) is increasing. Endoscopic surgical procedures are particularly afflicted by this problem because they require additional equipment. Increasing O.R. crowding may present unnecessary hazards to traffic and adversely affect the performance of the surgical team. The purpose of this study is to provide a quantitative summary of the furniture, equipment, cables, and tubes present during open and laparoscopic operations.
Methods: We prospectively studied an unselected series of general surgical open (OP, n=10) and laparoscopic (LAP, n=10) operations performed at a major university teaching hospital. We recorded the location of all furniture and equipment as well as the source, course, and destination of all cables and tubes in the O.R. Cables and tubes touching the surgeon or the assistant were particularly noted. Results are expressed as median values for each group.
Results: The percent of O.R. space occupied increased from OP=36% to LAP=41% (p<0.002). The median number of cables and tubes present increased from OP=27 to LAP=34 (p<0.0002), with the number of these lines touching a member of the surgical team increasing from OP=2 to LAP=6 (p<0.0003).
Conclusions: We conclude that there is a significant trend toward increasing O.R. crowding during laparoscopic surgery. Innovative designs will be needed to reduce clutter in the O.R. of the future. 相似文献
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Dave VP; Keefe R; Berger MA; Drbal K; Punt JA; Wiest DL; Alarcon B; Kappes DJ 《International immunology》1998,10(10):1481-1490
CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell
development. Here we explore the capacity of TCR-CD3 signaling complexes
expressed on delta degrees thymocytes to mediate the following functional
outcomes in response to antibody cross-linking: (i) the transition from the
CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to
CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We
provide evidence that CD3deltaepsilon complexes are dispensable for
mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the
other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that
CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8-
thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or
consecutive stimuli to elicit functional responses. Depending on the nature
of the secondary stimulus, delta degrees thymocytes can be induced to
undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken
together these results indicate that the signaling capacity of the TCR-CD3
complex is noticeably altered in the absence of CD3delta. The essential
role of CD3delta at the CD4+CD8+ stage of development correlates with the
onset of TCRalpha rearrangement, consistent with a critical structural
and/or functional relationship between CD3delta and TCRalpha.
相似文献
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150.
Kalman滤波分光光度法同时测定多相脂质体口服液中氟尿嘧啶和尼泊金的含量 总被引:1,自引:0,他引:1
本文提出了对测量值平滑后,用Kalman滤波分光光度法同时测定多相脂质体口服液中氟尿嘧啶和尼泊金的含量,改善了滤波效果,较好地解决了复杂基质存在下多组分的同时测定。用人工合成样考察表明,在269~273nm间滤波结果较好。用分别相当制剂标示量80,100,120%的两组分九种可能组合人工合成样品考查结果表明,氟尿嘧啶和尼泊金的回收率分别为99.3~102.6%和97.8~103.0%;当存在系统误差时,回收率分别为99.4~102.7%和97.0~102.9% 相似文献