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21.
Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively. 相似文献
22.
A组轮状病毒广州地方株VP7基因序列的比较分析 总被引:4,自引:0,他引:4
目的 了解我国轮状病毒G1型广州地方株与标准株及北京G1型地方株VP7基因序列的差异,为我国轮状病毒疫苗的研制提供资料。方法 通过逆转录—聚合酶链反应(RT—PCR)获得了轮状病毒广州地方株R97—196 VP7全基因的cDNA片段,将其克隆入T—A克隆质粒pUCm—T中,构建成重组质粒pUCmT—VP7,对克隆的VP7基因进行序列测定。结果 该地方株的基因核苷酸全长为1062nt,读码框架和以往的研究一致,和北京G1型地方株173的VP7氨基酸序列具有高度同源性(98%),而与不同血清型标准株间则变异较大(73%—81%),氨基酸序列中存在的一些高变区和保守功能区与已报道的研究结果一致。从进化角度分析,与轮状病毒标准株Wa株,相距较远。结论 轮状病毒广州地方株R97—196 VP7基因片段属G1型,轮状病毒VP7基因的变异与地域有一定关系。 相似文献
23.
Ru YX Wang HJ Yang BX Liu JH Li ZQ Li CW Wang JX Mi YC 《Ultrastructural pathology》2005,29(5):341-347
The objective of this study was to investigate the ultrastructural characteristics of hybrid acute leukemia (HAL). Fifteen cases of HAL were studied by transmission electron microscopy (TEM), focusing on organelles and myeloperoxidase (MPO) reaction of leukemic cells. By TEM, 5 out 15 cases of HAL were consistent with immunophenotyping (3 cases of biphenotypic type, and 2 cases of biclonal type with granulocytes and lymphocytes); 2 cases were suspected as HAL. On other hand, 5 cases of HAL were assigned to ALL, and 2 cases were misinterpreted as M5a and 1 as M4b. Most of the blast cells of biphenotypic HAL showed lymphoid features, except some cases containing MPO positive granules in blasts, while a few cases exhibited monocytic or nonspecific features. TEM offers advantages in the diagnosis of biclonal type HAL and biphenotypic HAL positive for MPO. However, it is difficult to differentiate MPO-negative cases of biphenotypic HAL from ALL and a few cases may be misinterpreted as M5 by TEM. 相似文献
24.
Shimokawa T Akita K Sato T Ru F Yi SQ Tanaka S 《Okajimas folia anatomica Japonica》2002,78(6):235-243
Detailed dissection was performed on eight head halves of four rabbits and six head halves of three dogs in order to investigate the nerve distributions to the m. retractor bulbi. Our observations indicated that the muscle was innervated by the branches of the abducens nerve in all sides which were examined in the present study. In addition, we observed that the ventral ramus of the oculomotor nerve gave rise to branches to the m. retractor bulbi in three sides of the rabbits, and in two sides of the dogs, which suggests that the innervation pattern of the muscle is variable even in the identical species. Considering these observations, we propose that the anlage of the m. retractor bulbi is mainly composed of the anlage innervated by the abducens nerve, and occasionally the anlage innervated by the ventral ramus of the oculomotor nerve is added to it, because the anlage of the m. retractor bulbi may be formed near the border region between the anlages innervated by the oculomotor and abducens nerves. 相似文献
25.
Epithelial-myoepithelial tumor is extremely rare as a pulmonary neoplasm. Only 20 cases have been reported to date, of which 14 were malignant. We report a case of intrabronchial epithelial-myoepithelial carcinoma in a 73-year-old man with a history of heavy smoking. The tumor was well-circumscribed and caused distal airway obstruction. Histologically, the tumor showed glandular and solid architecture. The glands were composed of an inner layer of epithelial cells and an outer layer of myoepithelial cells. The solid areas consisted of spindle-shaped myoepithelial cells. Immunohistochemical staining was positive for p53 and c-Kit (CD117). Focal atypia and increased mitotic activity were present, but no vascular invasion or nodal metastasis was identified. 相似文献
26.
E. Podsiadły J. Przyłuski A. Kwiatkowski M. Kruk M. Wszoła R. Nosek W. Rowiński W. Rużyłło S. Tylewska-Wierzbanowska 《European journal of clinical microbiology & infectious diseases》2005,24(8):507-513
Data published over the past decade show that Chlamydia pneumoniae is likely associated with the development of atherosclerosis. The aim of this study was to ascertain whether C. pneumoniae infections occur more frequently in patients with atherosclerosis than in healthy subjects. A total of 517 persons were studied. Serum samples, leukocytes, and tissue samples were assayed for the presence of C. pneumoniae-specific IgG and IgA antibodies and C. pneumoniae DNA. C. pneumoniae DNA was found in renal, iliac, and brachial vessels, but it was not detected in radial arteries. C. pneumoniae DNA was found most often in directional coronary atherectomy tissue specimens (11/41, 26.8%), but it was also found in the leukocytes of 14.9% (28/188) of patients with atherosclerosis and 24.6% (28/114) of patients without atheroma changes in vessels. Specific IgG and IgA antibodies were present in 63.8 and 49.9% of atheroma patients, respectively. The prevalence of C. pneumoniae antibodies differs significantly in patients with and without atherosclerosis (for IgG, p=0.002, and for IgA, p=0.006). The identification of persons with chlamydial infection of atherosclerotic arteries necessitates the examination of vascular tissues obtained during revascularization procedures. Serological investigation alone cannot identify individuals with vascular chlamydial infections. Detection of C. pneumoniae DNA in peripheral blood mononuclear cells does not seem to be the exclusive marker of persistent vascular infection. A more easily accessible parameter that allows prediction of chlamydial vascular infection is required. 相似文献
27.
28.
本文记述四川省峨眉山蚋属Simulium蚋亚属Simulium一新种,以中国科学院院士胡经甫命名为经甫蚋S.(S.)jinfful sp.nov.该蚋与S.(S.)himalayense Purl,1930,S.(S.)taiwanicum Takaoka,1979.S.(S.)shanxlense Cai and An,2003,S.(S.)immortalls Cai and An,2003,S.(S.)chamlongi Takaoka and Suzuki,1984相似,但是,雌虫的生殖叉突具内突和外突,肛上板椭圆形,前腿基节、转节、股节棕黄色;生殖腹板板体短,其长约为顶端宽度的0.8倍,与上述蚋种明显不同。模式标本保存在北京军事医学科学院医学昆虫标本馆。 相似文献
29.
目的:报告成人室间隔缺损的外科治疗经验。方法:对26例成人室间隔缺损的手术治疗进行回顾性分析。其中行室缺直接缝合3例,单纯补片修补19例,单向活瓣补片修补4例。同时行主动脉瓣折叠悬吊2例,双瓣置换l例,二尖瓣成成形l例,三尖瓣成形4例.结果:无手术死亡。术后并发症:切口感染、术后出血二次开胸止血、呼吸道感染和片周漏各l例,心动过速4例.术后随访24例(92.3%),随访时间1月~92月,晚期死亡l例,死因为片周漏并感染性心内膜炎.结论:成人室间隔缺损的临床表现虽较为复杂,手术效果令人满意.选择正确的手术方法及注意围术期处理是手术治疗成功的关键。 相似文献
30.
肝硬化患者红细胞内镁测定及其临床意义 总被引:1,自引:0,他引:1
目的 探讨肝硬化肝功能失代偿期患者红细胞内镁含量的变化及其临床意义。方法 研究对象为 32例肝硬化患者 ,按Child -Pugh分级法计肝功能B级 14例 ,C级 18例 ,合并肝性脑病 9例。对照组 5 9例为首次义务献血者。采用原子吸收光谱法测定受试者静脉血红细胞内镁浓度。结果 肝硬化组与对照组红细胞内镁浓度比较差异有非常显著意义 (P <0 .0 1)。肝硬化肝功能B级、C级红细胞内镁浓度与正常对照组比较均有非常显著差异 (P <0 .0 5 ,P <0 .0 1)。肝硬化合并肝性脑病 9例 ,其红细胞内镁浓度与C级无肝性脑病者比较 ,差异有非常显著意义 (P <0 .0 1)。结论 肝硬化患者红细胞内镁浓度的变化与肝性脑病的发生有一定关系。 相似文献