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11.
Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI.  相似文献   
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13.
Liver transplantation is currently the only effective therapy for patients with fulminant hepatic failure. The availability of an artificial liver could bridge these patients through the relatively brief crisis period and allow their own livers to regenerate, providing a more favorable outcome and sparing the trauma and expense of transplant. We have developed a device consisting of a highly differentiated human liver cell line cultured in a hollow fiber cartridge. This device is capable of supporting dogs with acetaminophen-induced fulminant hepatic failure for a period long enough for their own livers to resume function. Even though liver function tests such as albumin and prothrombin time became extremely abnormal during the course of the experiment, the dogs did not become encephalopathic. Two of the three treated animals recovered sufficient liver function after 42 to 48 hr of treatment that they could be disconnected from the device, and they survived the experiment. Histological results and serum ALT levels suggest that the device affected the course of the disease in two animals, allowing recovery of hepatocytes that would otherwise have lysed. In the third animal, regenerative nodules demonstrated that, even in the presence of severe liver injury, the device was capable of supporting total liver function.  相似文献   
14.
40 patients of stroke were studied. The results showed that in Cerebral hemorrhage the correlation between ascending Growth hormone (GH) of CSF and insulin of serum was negative, but the positive correlation between ascending GH (CSF) and hyperglycemia. In patients of cerebral thrombosis the results of values above were no correlation. The pathological significance in such cases was discussed.  相似文献   
15.
目的:评价口服水剂、水灌肠及两者联合应用充盈肠道后,使用MSCT显示成人正常肠道的能力。材料和方法:将43名非肠道病变志愿者分别采用口服水剂法(21例)、水灌肠法(12例)、双重法(口服水剂和水灌肠联合应用,10例)充盈肠道,然后行MSCT平扫和增强扫描并进行图像重建,对小肠和大肠各肠段充盈状态进行评价。结果:口服水剂法回肠充盈良好,水灌肠法大肠充盈良好,双重法回肠及大肠均充盈良好。口服水剂法小肠充盈优于水灌肠法,与双重法无显著差异,大肠充盈状态水灌肠法明显优于口服水剂法,与双重法无显著差异。结论:口服水剂和水灌肠联合应用可以在MSCT同时较好地充盈显示小肠和大肠,而两种方法单独使用则仅能分别充盈显示小肠和大肠,需要根据显示目的选择相应的充盈方法。  相似文献   
16.
本文介绍了一种应用微机BASIC语言的屈光学矩阵算法程序,可方便、迅速地解决许多眼科屈光学计算问题,如共轴球面折射系统、共轴球面反射、折射系统、球、柱镜偏心棱镜效应计算和散光柱镜系统的斜交球、柱镜组合计算等等。  相似文献   
17.
Two middle-aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14-3-3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion-weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt-Jakob disease. (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14-3-3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI-MRI imaging and CSF protein 14-3-3 studies were both performed. Among 19 reported cases of CJD with DWI-MRI lesions, CSF protein 14-3-3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI-MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14-3-3. These observations provide a compelling rationale for a prospective comparative study.  相似文献   
18.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
19.
目的 探讨转化生长因子β(TGF-β)对人的颈椎关节突关节透明软骨细胞基质金属蛋白酶13(MMP-13)基因表达的作用,旨在阐明颈椎退行性变的相关发生机理。方法 应用逆转录方法PCR及实时荧光定量方法,检测不同浓度TGF-β作用传代培养人的透明软骨细胞MMP-13mRNA的含量。另外3种不同浓度分别与10ng/ml IL-1β组成联合作用组,共计6个实验组及1个正常对照组。结果 正常对照组中透明软骨细胞仅见MMP-13mRNA扩增产物,实验组TGF-β1、10和100ng/ml作用12h后,MMP-13mRNA表达逐渐增强;而联合作用组中,随着TGF-β1浓度的升高,MMP-13mRNA表达逐渐降低,并且各组之间存在明显的差异(P〈0.05)。结论 TGF-β可按剂量依赖方式调节颈椎关节突关节软骨细胞MMP-13mRNA的表达。  相似文献   
20.
目的 总结、分析150例电视胸腔镜心血管外科手术的临床结果。方法 应用电视胸腔镜手术技术对动脉导管未闭、房间隔缺损、室间隔缺损、三尖辨关闭不全、冠状动脉-肺动脉瘘、心包积液、原发性长Q-T综合征、雷诺病,心包囊肿等进行治疗。结果 动脉导管未闭均成功在胸腔镜下钳闭;房缺、室缺在胸腔镜体外循环下进行补片修补,冠状动脉瘘胸腔镜下修补;心包积液进行心包活检与开窗引流;长Q-T综合征进行胸腔镜下左T2、T3胸交感神经节切除,均无严重并发症,术后患者恢复良好。结论 电视胸腔镜心血管外科手术可取得满意的临床治疗结果。  相似文献   
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