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991.
An undulation pump is a special rotary blood pump in which rotation of a brushless DC motor is transformed to an undulating motion by a disc in the pump housing attached by means of a special link mechanism. In the blood pump, a closed line between the disc and housing moves from the inlet to the outlet by this undulating disc motion, which sucks and pushes the blood from the inlet to the outlet. Because the same phenomena occurs at both sides of the disc, a continuous flow is obtained when the motor rotational speed is constant. The pump flow pattern can be easily changed from continuous flow to pulsatile flow by controlling the motor drive current pattern. A seal membrane made of segmented polyurethane protects the blood from invading the link mechanism as well as the motor. UPTAH is fabricated with two undulation pumps and two brushless DC motors. Its size is 75 mm in diameter and 80 mm long, and it has one of the great advantage of no compliance chamber required in the system. UPTAHs were implanted under cardiopulmonary bypass (CPB) into the chest cavities of 16 goats, each weighing between 41 and 72 kg. No anticoagulant and antiplatelet agent was used after the surgery. The left atrial pressure was automatically controlled to prevent its elevation and sucking of the atrial wall into the atrial cuff. The following results were obtained: (1) UPTAHs fit well into all the goats; (2) the longest survival was 19.8 days, the cause of death was bleeding from the aortic anastomosis; (3) No thrombus was observed in the blood pump despite no anticoagulant use. Hemolysis depended upon the length of CPB during surgery. When CPB time was within 2 hours, hemolysis level returned to baseline within a few days of the surgery. UPTAH is a promising implantable TAH, because of its small size and easy controllability.  相似文献   
992.
In addition to their well-characterized role in allergic inflammation, recent data confirm that mast cells play a more extensive role in a variety of viral infections. The contribution of mast cells to Newcastle disease pathogenesis has not been investigated. We evaluated mast cell activity after Newcastle disease virus (NDV) infection in specific pathogen free chickens using cytochemical and immunocytochemical analyses. The results were as follows. Severe tissue damage was observed in the proventriculus, duodenum, jejunum and caecal tonsil, and NDV antigens were detected and presented extensively in these tissues. Second, in the NDV-infected group, the mast cell population was increased markedly in the proventriculus, duodenum, jejunum and caecal tonsil at 24, 48, 72 and 96 h after infection (P<0.01). However, very few mast cells were observed in those same tissues in the control. More intriguingly, the greatest number of mast cells was found in the proventriculus, which also showed the greatest level of NDV antigens. Third, the content of tryptase was significantly higher (P<0.01) in the NDV-infected group compared with the control from 24 to 96 h post infection). Furthermore, as an important protease released by mast cells, tryptase had a positive correlation with mast cell distribution. These data indicated that mast cells were involved in the response to NDV. Our results also suggested that the broad range of mast cell mediators might have a role in the pathology of Newcastle disease.  相似文献   
993.
目的:对腰丛及其周围的组织结构进行可视化的研究,为微创手术提供更精确的数据和解剖学资料.方法:利用“虚拟中国人“Ⅰ号女性数据集,重建腰丛及其周围组织结构的三维可视化模型.结果:通过数字人数据集重建的三维图片显示腰丛神经及其主要分支与主要血管和椎体及肾脏之间的关系,又可清楚的显示腰丛神经与腰大肌之间的关系.结论:数字人数据集可提供腰丛和周围组织器官的断层图片,为腰丛的解剖学位置及腰椎前路手术提供了形态依据.  相似文献   
994.
A laboratory-based surveillance network of 11 clinical virological laboratories for influenza viruses was established in Taiwan under the coordination of the Center for Disease Control and Prevention (CDC), Taiwan. From October 2000 to March 2004, 3,244 influenza viruses were isolated, including 1,969 influenza A and 1,275 influenza B viruses. The influenza infections usually occurred frequently in winter in the northern hemisphere. However, the influenza seasonality in Taiwan was not clear during the four seasons under investigation. For example, the influenza A viruses peaked during the winters of 2001, 2002, and 2003. However, some isolated peaks were also found in the summer and fall (June to November) of 2001 and 2002. An unusual peak of influenza B also occurred in the summer of 2002 (June to August). Phylogenetic analysis shows that influenza A isolates from the same year were often grouped together. However, influenza B isolates from the year 2002 clustered into different groups, and the data indicate that both B/Victoria/2/87-like and B/Yamagata/16/88-like lineages of influenza B viruses were cocirculating. Sequence comparison of epidemic strains versus vaccine strains shows that many vaccine-like Taiwanese strains were circulating at least 2 years before the vaccine strains were introduced. No clear seasonality of influenza reports in Taiwan occurred in contrast to other more continental regions.  相似文献   
995.
Guidance cues along the longitudinal axis of the CNS are poorly understood. Wnt proteins attract ascending somatosensory axons to project from the spinal cord to the brain. Here we show that Wnt proteins repel corticospinal tract (CST) axons in the opposite direction. Several Wnt genes were found to be expressed in the mouse spinal cord gray matter, cupping the dorsal funiculus, in an anterior-to-posterior decreasing gradient along the cervical and thoracic cord. Wnts repelled CST axons in collagen gel assays through a conserved high-affinity receptor, Ryk, which is expressed in CST axons. Neonatal spinal cord secretes diffusible repellent(s) in an anterior-posterior graded fashion, with anterior cord being stronger, and the repulsive activity was blocked by antibodies to Ryk (anti-Ryk). Intrathecal injection of anti-Ryk blocked the posterior growth of CST axons. Therefore, Wnt proteins may have a general role in anterior-posterior guidance of multiple classes of axons.  相似文献   
996.
目的 探讨肝黏膜相关淋巴组织淋巴瘤的临床病理特征。方法 对1例罕见多脏器恶性肿瘤术后肝黏膜相关淋巴瘤病例结合文献进行临床、病理和免疫组化分析。结果 患者于8年和3年前先后发生胃恶性间质瘤、阴囊阴茎皮肤湿疹样癌,有长期化疗史。肿瘤组织学以单核样B细胞为主,并有淋巴滤泡和淋巴上皮病变形成。免疫表型示瘤细胞CD45、CD79α、CD20阳性,CD5、CD10、ALK、TdT阴性,bcl—2、Ki—67少数肿瘤细胞阳性。结论 肝黏膜相关淋巴瘤可以发生于多脏器恶性肿瘤术后,其发病可能与长期使用免疫抑制剂有关,诊断本病时需与肝继发性淋巴瘤及肝的炎性假瘤鉴别。  相似文献   
997.
研究单次提取兔体感诱发电位,并定位和分析诱发电位波形成分。麻醉兔,以0.5Hz频率电脉冲刺激兔下肢隐神经,3764Hz采样率收集兔头皮电位。采用一维多分辨分析提取兔体感诱发电位,并用连续小波变换定位和分析诱发电位波形成分。单次诱发电位的小波变换与叠加平均诱发电位比较,表明Daubechies小波多分辨分析可以单次提取诱发电位。连续小波变换能够精确定位诱发电位中波形成分,并可采用连续小波变换分析诱发成分的频域特性。连续小波变换技术把一维时域信号投影到二维时频空间研究将成为医学信号处理的一个有用方法。  相似文献   
998.
ABSTRACT

The H7 subtype avian influenza virus (AIV) has been reported to infect not only poultry but also humans. The haemagglutinin (HA) protein is the major surface antigen of AIV and plays an important role in viral infection. In this study, five monoclonal antibodies (mAbs, 2F8, 3F6, 5C11, 5E2 and 5C12) against the HA protein of H7 virus were produced and characterized. Epitope mapping indicated that 103RESGSS107 was the minimal linear epitope recognized by the mAbs 2F8/3F6/5C11, and mAbs 5E2/5C12 recognized the epitope 103-145aa. The protein sequence alignment of HA indicated that the two epitopes were not found in other subtypes of AIV, and none of the five mAbs cross-reacted with other subtypes, suggesting these mAbs are specific to H7 virus. The epitope 103RESGSS107 was highly conserved among Eurasian lineage strains of H7 AIV, whereas three amino acid substitutions (E104R, E104K and E104G) in the epitope occurred in 98.44% of North-American lineage strains. Any of these single mutations prevented the mutated epitope from being recognized by mAbs 2F8/3F6/5C11; thus, these mAbs can distinguish between Eurasian and North-American lineages of H7 strains. Furthermore, the mAbs 2F8, 3F6 and 5C11 could be highly blocked with H7-positive serum in blocking assays, revealing that 103RESGSS107 may be a dominant epitope stimulating the production of antibodies during viral infection. These results may facilitate future investigations into the structure and function of HA protein, as well as surveillance and detection of H7 virus.

RESEARCH HIGHLIGHTS
  • Five mAbs against HA protein of H7 AIV were generated and characterized.

  • Two novel epitopes 103RESGSS107 and 103-145aa were identified.

  • The epitope 103RESGSS107 differs between Eurasian and North-American lineages.

  • The mAbs 2F8, 3F6 and 5C11 could distinguish two lineages of H7 strains.

  相似文献   
999.
目的探讨西酞普兰与马普替林治疗老年抑郁症的疗效和不良反应。方法将80例老年抑郁症患者随机分成两组,一组服用西酞普兰,另一组服用马普替林,疗程6周。采用汉密顿抑郁量表(HAMD)及药物副反应量表(TESS)定疗效和不良反应。结果西酞普兰组显效率为80%;马普替林组显效率为72.5%,两组差异无显著性。西酞普兰组不良反应较马普替林组少而轻。结论西酞普兰治疗老年抑郁症的疗效确切,起效快,不良反应轻,依从性好。  相似文献   
1000.
INTRODUCTION—Papillon-Lefèvre syndrome (PLS) is an autosomal recessive disorder characterised by palmoplantar keratoderma and severe, early onset periodontitis, which results from deficiency of cathepsin C activity secondary to mutations in the cathepsin C gene. To date, 13 different cathepsin C mutations have been reported in PLS patients, all of which are homozygous for a given mutation, reflecting consanguinity.
AIM—To evaluate the generality of cathepsin C mutations in PLS, we studied an ethnically diverse group of 20 unrelated families.
METHODS—Mutations were identified by direct automated sequencing of genomic DNA amplified for exonic regions and associated splice site junctions of the cathepsin C gene. Long range PCR was performed to determine the genomic structure of the cathepsin C gene.
RESULTS—The cathepsin C gene spans over 46 kb, with six introns ranging in size from 1.6 to 22.4 kb. Eleven novel mutations and four previously reported mutations were identified in affected subjects from 14 families. Missense mutations were most common (9/15), followed by nonsense mutations (3/15), insertions (2/15), and deletions (1/15). Among these 14 probands, two were compound heterozygotes. Affected subjects with transgressions of the dermal lesions onto the knees or elbows or both had mutations in both the pro- and mature regions of the enzyme, although most were in the mature region.
CONCLUSION—Mutations in the mature region of cathepsin C were more likely to be associated with the transgressions of the dermatological lesions, although the results were not statistically significant. A comprehensive list of all cathepsin C mutations described to date, representing 25 mutations from 32 families with PLS and related conditions, is also presented.


Keywords: cathepsin C; genetics; severe early onset periodontitis; hyperkeratosis  相似文献   
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