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21.
尺神经深支,骨间前神经旋前方肌支的应用解剖   总被引:2,自引:1,他引:2  
尺神经深支向近侧无损伤分离后,可超越旋前方肌上缘以上26.58mm,此时宽1.80mm、厚1.00mm,可与宽1.35mm、厚0.89mm的旋前方肌支缝合。  相似文献   
22.
A microplate assay for the detection of bactericidal antibodies to Vibrio cholerae O139 is described. The assay is sensitive, highly reproducible, specific, and convenient to perform. It has been used to demonstrate the induction of serum bactericidal antibodies in Vietnamese recipients of an oral, inactivated, bivalent O1/O139 vaccine, as well as in Bangladeshi patients with O139 disease. In both study groups there was a significant inverse correlation between the preexposure level of antibodies in serum and the magnitude of the subsequent bactericidal response. Although infection generated stronger responses than vaccination, the proportion of responders was similar among individuals with low background titers.  相似文献   
23.
High-level gains at 5p15, a chromosomal region including the human telomerase catalytic protein subunit (hTERT) gene, have been documented in several medulloblastomas. We therefore analyzed hTERT gene dosage in a group of medulloblastomas and other embryonal brain tumors using differential PCR. Amplification of the hTERT locus was detected in 15 of 36 (42%) tumors examined. To correlate gene amplification with message level, we used real-time quantitative PCR to measure hTERT mRNA in 50 embryonal brain tumors. hTERT mRNA was detected in all but one of these cases, and mRNA level correlated significantly with gene dosage (r = 0.82). Log-rank analysis of survival data revealed a trend toward poor clinical outcomes in patients with medulloblastomas containing high hTERT mRNA levels, but clinical follow-up was relatively short and the association was not statistically significant (P = 0.078). Comparative genomic hybridization was used to further analyze the tumor with the greatest hTERT gene dosage and mRNA level, a recurrent medulloepithelioma. hTERT was amplified in the recurrent tumor but not in the primary lesion, suggesting this locus can be involved in tumor progression. Our data indicate that hTERT gene amplification is relatively common in embryonal brain tumors, and that increased expression of hTERT mRNA may be associated with biologically aggressive tumor behavior.  相似文献   
24.
Fetal rat skin transitions from scarless fetal-type repair to adult-type repair with scar between day 16 (E16) and day 18 (E18) of gestation (term = 21.5 days). Deficient transforming growth factor (TGF)-beta 1 and -beta 2 injury response has been proposed as a mechanism for scarless fetal-type repair. However, previous fetal studies have inconsistently reported the degree of TGF-beta induction after injury. To minimize developmental variables in fetal versus adult TGF-beta regulation, we narrowed our study to wounded fetal animals. We hypothesize that TGF-beta ligand and receptor expression will be differentially regulated during the transition from early gestation (E16) wounds manifesting scarless fetal-type repair to late gestation (E19) wounds manifesting adult-type repair with scar. In this study, decreased and rapidly cleared TGF-beta 1 and -beta 2 expression accompanied by increased and prolonged TGF-beta 3 levels in wounded E16 animals correlated with organized collagen deposition. In contrast, increased and prolonged TGF-beta 1 and -beta 2 expression accompanied by decreased and delayed TGF-beta 3 expression in wounded E19 animals correlated with disorganized collagen architecture. Similarly, expression of TGF-beta receptors type I and II were also increased or prolonged in E19 animals. Our results implicate increased TGF-beta 1, -beta 2, and decreased TGF-beta 3 expression, as well as increased type I and II receptor expression in late gestation fetal scar formation.  相似文献   
25.
A study involving more than 2,000 infants was conducted in Vietnam to assess the field effectiveness and immunogenicity of recombinant hepatitis B vaccine given at birth, 1 month, 2 months, without concomitant hepatitis B immune globulin (HBIG). All received a 5 microg dose of H-B-VAX II at birth. Infants born to non-carrier mothers (Group 1; N = 1798) then received 2.5 microg doses at 1 and 2 months of age, while infants of HBeAg-negative (Group 2; N = 125) or HBeAg-positive (Group 3; N = 88) carrier mothers received 5 microg doses. No Group 1 or 2 vaccinees were infected. In Group 3, 12 (14.6%) of 82 infants did become infected (estimated efficacy 84%). 98.0-98.6% of uninfected infants who were tested for anti-HBs developed a seroprotective concentration > or = 10 IU/L. In hyperendemic Vietnam, where routine maternal screening and passive-active prophylaxis of high-risk infants with vaccine plus HBIG is not feasible, administration of vaccine alone to all newborns may control effectively HBV infection.  相似文献   
26.
The TGF-1(–/–) mouse is a murine model for systemic autoimmune disease. The aim of this study is to elucidate the immunological mechanism that leads to multifocal tissue inflammation and autoantibody production in TGF-1(–/–) mice. Heart, lung, liver, and salivary gland from TGF-1(–/–) were assessed for CD154 expression by RT-PCR and immunohistochemistry. Compared to wild-type littermates, CD154 expression was elevated in all tissues studied. Furthermore, IL-12 mRNA was expressed in the salivary gland and heart of TGF-1(–/–) mice and not in wild-type littermates. This suggests that the CD154 pathway is activated in these tissues. This shows that TGF-1 regulates CD154 expression leading to spontaneous IL-12 production and autoimmunity.  相似文献   
27.
In a double-blind, randomized, and placebo-controlled previous trial, the efficacy of Vi-rEPA for typhoid fever in 2- to 5-year-olds was 89.0% for 46 months. Vi-rEPA contained 25 microg of Vi and induced a greater-than-eightfold rise in immunoglobulin G (IgG) anti-Vi in all of the vaccinees tested. In this investigation, we conducted a dosage-immunogenicity study of 5, 12.5, and 25 microg of Vi-rEPA in this age group. Two doses of Vi-rEPA were injected 6 weeks apart. Blood samples were taken before and at 10 weeks (4 weeks after the second injection) and 1 year later. All postimmunization geometric mean (GM) levels were higher than the preimmune levels (P < 0.0001). At 10 weeks, the GM IgG anti-Vi level elicited by 25 microg (102 EU/ml) was higher than those elicited by 12.5 microg (74.7 EU/ml) and 5 microg (43 EU/ml) (P < 0.004): all of the children had > or = 3.52 EU/ml (estimated minimum protective level). One year later, the levels declined about sevenfold (13.3 and 11.3 versus 6.43 EU/ml, P < 0.0001) but remained significantly higher than the preimmune levels (P < 0.0001), and >96% of the children had a greater-than-eightfold rise. This study also confirmed the safety and consistent immunogenicity of the four lots of Vi-rEPA used in this and previous trials.  相似文献   
28.
桡神经及其深支的血供   总被引:1,自引:0,他引:1  
在25具成人尸体(50例)上,观测了桡神经及其深支的血供。桡神经的营养动脉平均为4.36±0.26支,营养动脉和来源动脉的外径平均为0.38±0.08mm和1.65±0.05mm。桡神经深支的营养动脉平均为1.72±0.16支,营养动脉和来源动脉的外径平均为0.29±0.01mm和1.91±0.07mm。  相似文献   
29.
Superoxide anion (O2°-)production by neutrophil NADPH oxidase participates in arthritic joint lesion formation. Proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin 8 (IL-8) and granulocyte/macrophage-colony stimulating factor (GM-CSF) have a priming effect on neutrophil NADPH oxidase activity. NADPH oxidase activation is dependent on phosphorylation of p47phox, a cytosolic component of the enzyme. We studied O2°-production and p47phox phosphorylation in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA) according to TNF, IL-8 and GM-CSF levels. O2°-production by neutrophils isolated from SF of all the arthritis patients (RA and SpA) was higher than that of circulating resting neutrophils and when stimulated with fMLP or PMA. In addition, p47phox was partially phosphorylated in SF neutrophils compared to circulating neutrophils. High levels of TNF and IL-8 (but not GM-CSF) are detected in patient's SF (compared to circulating blood levels). TNF levels were significantly higher in RA than in SpA SF. These results suggest that increased NADPH oxidase activity could be involved in arthritic joint inflammation through increased p47phox phosphorylation. This could be the result of the presence of high levels of priming agents such as TNF and IL-8 but not GM-CSF.  相似文献   
30.
党小荣  张文斌 《神经解剖学杂志》2002,18(2):173-177,T036
应用四甲基罗达明逆行标记和免疫荧光技术相结合 ,在激光扫描共聚焦显微镜下对大鼠孤束核内 5 -HT能纤维和终末与向臂旁核投射的 NOS阳性神经元之间的联系进行了观察。将四甲基罗达明注入一侧外侧臂旁核后可见孤束核尾段背内侧、胶质、小细胞、内侧、中间内侧等亚核和连合亚核内出现较多的逆标神经元 ,四甲基罗达明逆标和 NOS阳性神经元以及 5 -HT阳性终末重叠分布 ,其中四甲基罗达明和 NOS双重阳性神经元分别占四甲基罗达明逆标和 NOS阳性神经元总数的 8.3% ( 14 /16 8)和 18.4% ( 14 /76 )。在此 5 -HT样阳性纤维和终末包绕着 NOS阳性神经元、四甲基罗达明逆标神经元及四甲基罗达明和一氧化氮合酶双重阳性神经元的胞体和树突 ,形成点状紧密接触。本研究结果提示 ,孤束核内来自下行性抑制系统的 5 -HT能纤维和终末可能与向臂旁核投射的 NOS阳性神经元形成突触联系 ,从而可对 NOS阳性神经元所传递的包括伤害性信息在内的内脏感觉传入信息发挥抑制性调控作用  相似文献   
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