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111.
Molecular epidemiology of rabies virus isolates from South Korea   总被引:5,自引:0,他引:5  
Hyun BH  Lee KK  Kim IJ  Lee KW  Park HJ  Lee OS  An SH  Lee JB 《Virus research》2005,114(1-2):113-125
  相似文献   
112.
Summary Cephalic pancreatoduodenectomy (CPD) with pylorus preservation has been suggested to improve the functional and nutritional result of surgery. At operation, the first two centimeters of the duodenum are preserved, the vascular arch of the lesser gastric curvature is saved and the right gastroepiploic artery is resected at its origin. The aim of this study on 15 fresh cadavers was to determine the origin of the vascularization of the remaining duodenum and also the possibilities of preserving an optimal vascularization after CPD and pylorus preservation. All of the arteries supplying the remaining duodenum and arising either from the right gastric artery or the right gastroepiploic artery were identified. The distances between the origin of the infrapyloric artery and the termination of the gastroduodenal artery on the cranial and ventral pancreaticoduodenal artery and the left gastroepiploic artery were measured. At CPD with pylorus preservation, the study demonstrated that: 1) the cranial side of the remaining duodenum remains vascularized in 80% of the cases by one or two supraduodenal branches coming from the right gastric artery; 2) ligation of the right gastroepiploic artery eliminates all vascular supply to the caudal side of the remaining duodenum in almost half of the cases; 3) in these cases, the dissection of the bifurcation of the gastroduodenal artery and the vascular section beyond the origin of the infrapyloric artery allowed a direct vascular supply to the remaining duodenum to be preserved.This work was presented at the French Section of the European Association of Clinical Anatomy meeting, Bobigny, France, 1992  相似文献   
113.
本文测定了30例正常育龄妇女,28例正常妊娠以及36例妊娠征患者血浆中降钙素基因相关肽的水平,结果发现,轻度妊高生与正常妊娠相比,血浆中CGRPK是有下降但不显著(P〉0.05)。中重度妊高征与正常妊娠相比,差异有非常显著性,因此推测,妊娠状态下血浆中降钙素基因相关肽的减少可能是妊娠高血压症产生的重要原因之一。  相似文献   
114.
胎儿消化器官发育中的肥大细胞超微结构特点   总被引:3,自引:0,他引:3  
实验对10例不同胎龄肥儿消化器官的胎大细胞进行了超微结构观察,发现胎儿发育接近成熟时,其肥大细胞根据颗粒的超微结构可分TC肥大细胞和T肥大细胞两型;胎儿发育后期以大细胞有分泌活动呈活化状态;胎儿肥大细胞与成纤维细胞,上皮细胞,血管,神经等密切接触。  相似文献   
115.
Chen W  Wang J  An H  Zhou J  Zhang L  Cao X 《Immunology letters》2005,98(1):153-159
Toll-like receptors (TLRs) play a critical role in innate immunity and TLR9 is essential for CpG ODN signaling. As "dangerous signal", heat shock may regulate immune response. However, little is known about TLRs expression and signaling after heat shock. In this study, we investigated regulation of TLR9 expression and function in human B cell line RPMI8226 by heat shock. We demonstrated that TLR9 expression was up-regulated remarkably following heat shock. Coincidently, CpG ODN stimulation significantly increased IL-6 production and up-regulated expressions of MHC I, MHC II and CD86 by heat-shocked B cells. Heat shock activated ERK and NF-kappaB signal pathways, and pretreatment of B cells with specific inhibitors of ERK or NF-kappaB signal pathways inhibited heat shock-induced up-regulation of TLR9 expression. These results demonstrated that heat shock promotes TLR9 expression and signaling through activation of ERK and NF-kappaB signal pathways in B cells, suggesting that heat shock might modulate host immune response by regulating TLR expression.  相似文献   
116.
In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats.  相似文献   
117.
118.
The present study was designed to ascertain whether the negative effects on reproductive potential of post-ovulatory ageing in vitro of oocytes can be prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were aged in vitro for 12 h prior to insemination in the presence of varying concentrations of L-ascorbic acid, 6-methoxy- 2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta- mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was associated with lower fertilization rate, higher proportion of concepti exhibiting cellular fragmentation at 24 h post-insemination and lower percentage of concepti reaching the blastocyst stage. Ascorbic acid, Trolox and EDTA had no effect on cellular fragmentation or potential of oocytes for development. However, the probability of an oocyte reaching the blastocyst stage was decreased (P < or = or = 0.05) in oocytes incubated in the presence of L-cystine (50 and 500 microM) and beta-mercaptoethanol (5, 50 and 500 microM) when compared to control aged oocytes. Age-associated cellular fragmentation at 24 h post-insemination was partially prevented (P < or = 0.05) by incubating oocytes in the presence of beta-mercaptoethanol (500 microM). DTT (50 and 500 microM) increased (P < or = 0.05) fertilization rate and number of cells at 81 h post-insemination to levels similar to those exhibited by control oocytes. Furthermore, both age-associated fragmentation at 24 h post-insemination (P < or = 0.05) and decreased potential of oocytes for development to the blastocyst stage (P < or = 0.05) were prevented, at least in part, by culturing oocytes in the presence of DTT (50 microM). Although the mechanism by which DTT exerts its beneficial effects on aged oocytes remains to be elucidated, it may protect oocytes by preventing oxidation of free thiol groups and/or altering a redox-independent signalling pathway that mediates cellular fragmentation and death.   相似文献   
119.
The present study was performed to determine whether the effects induced by GABA(B) receptor-acting drugs would be related with the alteration in GABA(B) receptor expression in the hippocampus using Mongolian gerbil, a genetic epilepsy model. The distribution patterns of both GABA(B) receptor 1A/B and GABA(B)receptor 2 immunoreactivities were similarly detected in the hippocampi of normal and seizure-prone gerbils. Following baclofen (GABA(B) receptor agonist) or phaclofen (GABA(B) receptor antagonist) treatment, GABA(B) receptor immunoreactivities were decreased or increased by dose-dependent manners, respectively. Vigabatrin (GABA transaminase inhibitor) or 3-mercaptopropionic acid (GAD inhibitor) treatment did not affect GABA(B) receptor expressions. These findings suggest that GABA(B) receptor expression in the gerbil hippocampus may be altered by baclofen or phaclofen treatment.  相似文献   
120.
Using a new antibody, we found previously that contrary to adult natural killer (NK) cells, fetal NK cells have a unique phenotype, as they exclusively express Ly49E. This can be explained by an intrinsic different NK differentiation potential of fetal versus adult lymphoid progenitors, by immaturity of fetal NK cells or by instability of Ly49E expression. Here, we show that adult progenitor cells were still capable of differentiating into Ly49E-expressing NK cells but at a much lower frequency. Surprisingly, Ly49E expression in vitro did not require stromal cells. Kinetic analysis in vivo showed that Ly49E was expressed early, together with CD94/NKG2 and Ly49G2, followed by Ly49C, and finally Ly49D. Transfer of sorted Ly49E-positive fetal NK cells showed stable Ly49E expression, and later, part of these cells up-regulated other Ly49 members. These data indicate that although there are intrinsic differences, there is no strict fetal and adult wave of NK cell differentiation.  相似文献   
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