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121.
Ryoichi Sakamoto Tetsuya Nitta Yoshiaki Kamikawa Kazumasa Sugihara Kazuhisa Hasui Shinichiro Tsuyama Fusayoshi Murata 《Medical Electron Microscopy》2004,37(1):52-61
The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis. 相似文献
122.
人血清载脂蛋白H的纯化与鉴定 总被引:1,自引:0,他引:1
为了研究载脂蛋白H(apoH)与疾病的关系,分别用HClO4,(NH4)2SO4沉淀、DEAE-纤维素离子交换层析,从人血清中纯化了载脂蛋白Ho用测定分子量,分析氨基酸组成和N-端氨基酸测序三个方面进行鉴定。用SDS-PAGE测得其相对分子量对54000。用高效液相色谱测定其中15种氨基酸的相对含量(mol/10^3mol残基)如下:Asp119.8,Glu108,Thr94.8,Ser78.6,Phe64.9,Gly1008,Ala57.2,Val57.2,Met10.6,Ile50.3,Leu77.1,Tyr31.9,His15.2,L-ys81.4,Arg39.4;d PE-ABI公司生产的475A型气相蛋白质测序仪上测得其N端10个氨基酸残基顺序如下:NH2-Gly-Arg-Cys-Pro-Asp-Asp-Leu。纯化得到的apoH与肝素有高的亲和性,还能与乙肝表面抗原结合。纯化apoH的方法相对比较简单,能达到测序的要求。 相似文献
123.
Adjunct effect of loratadine in the treatment of acute sinusitis in patients with allergic rhinitis 总被引:1,自引:2,他引:1
J. J. Braun J. P. Alabert F. B. Michel M. Quiniou C. Rat J. Cougnard W. Czarlewski J. Bousquet 《Allergy》1997,52(6):650-655
H1 -blockers are often added to the standard treatment of acute sinusitis, but this is not supported by a controlled study. A multicentric, randomized, double-blind, placebo-controlled, parallel-group study was done in 139 allergic patients (15–65 years) to assess the adjunct efficacy of loratadine in acute exacerbation of rhinosinusitis. Sinusitis was diagnosed by symptoms and confirmed by rhinoscopy and sinus radiograph. Allergy was characterized by skin tests, RAST, and history. Patients were treated with antibiotics (14 days), oral corticosteroids (10 days), and loratadine (10 mg OD) or placebo (28 days). Treatment efficacy was assessed over 28 days by symptom scores quoted daily by patients. Physicians also rated total symptom scores at entry and at day 28. At entry, both groups had similar symptoms. Placebo-treated patients improved significantly, but patients who received loratadine had a significantly greater improvement in sneezing ( P =0.003) after 14 days, and in nasal obstruction ( P =0.002) after 28 days. Physicians found that patients receiving loratadine were significantly improved compared to placebo patients ( P =0. 0125). Loratadine in addition to standard therapy was found to improve the control of some symptoms of sinusitis. 相似文献
124.
On the basis of previous empirical research it was hypothesised that (a) antisocial behaviour in adolescence would be characterised by lower tonic heart rate levels and (b) any such relationship would be particularly borne out in the higher social classes where the 'social push' towards antisociality may be relatively weaker. These predictions were tested by relating tonic heart rate levels in a sample of 15 year old male schoolchildren to self-report and teacher ratings of antisocial behaviour/undersocialization. An 'antisocial' group was found to have significantly lower heart rate levels than a 'prosocial' group. Several analyses on high and low class groups resulted in a significant low heart rate/antisociality relationship in the high classes only. It was speculated that the heart rate/antisociality relationship may be mediated by somatotype, or alternatively that low levels in high class antisocials may reflect a vagal passive adaptation to mildly aversive events. 相似文献
125.
从人分离出两株甲型流感H9N2亚型毒株内部基因特性的研究 总被引:5,自引:1,他引:5
目的 了解2株从人分离出的H9N2亚型毒株内部基因特性,并弄清其来源。方法 用RT-PCR扩增目的基因,用P^CEM-T Vector(美国Promega公司),4℃过夜连接,重组质粒转入dH5a细菌,筛选阳性菌落,酶切鉴定,送六合通公司自动测序。然后进行进化树分析。结果 2株测定毒株内部基因均为G9基因系,它们相互间除PA基因有差异外,其余5个基因均相同。结论 2株测定毒株的基因组均为G9基因系,它们是由携带不同基因特性H9N2毒株的禽群分别直接感染人,而不是来自同一禽的H9N2亚型流感病毒。 相似文献
126.
H1N2新亚型流感病毒神经氨酸酶基因来源的进一步研究 总被引:1,自引:0,他引:1
对流感病毒H1N2亚型重组株A/哈防/1/88、A/哈防/12/92以及H3N2亚型病毒株A/雅防/2/87、A/京防/57/898和A/粤防/1/92神经氨酸酶(NA)基因核苷酸全序列的测定,进一步弄清了A/哈防/1/88病毒株的NA基因确来自当时人群中流行的H3N2亚型病毒株,很可能是来自A/雅防/2/87类病毒株;而A/哈防/12/92病毒株的NA基因可能是与A/哈防/1/88病毒株的NA基 相似文献
127.
This study examined the relationship between muscle activity and the increased pupillary dilation observed during cognitive tasks when S is required to indicate task completion. Pupillary and EMG activity were monitored while Ss generated images to words. In two groups, Ss indicated completion of the task either by pressing a key or by releasing it. In two other groups Ss made a key press response that was unrelated to the cognitive task. No key press was required of a fifth group. Results indicated some apparent effect of muscle activity on pupil size during the imagery task and the findings were discussed in relation to other variables affecting pupillary activity. 相似文献
128.
129.
Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies 总被引:1,自引:0,他引:1
Terresa Nusair Reuben Baumal Robert Rosenstein Trond Jørgensen Alexander Marks 《Molecular immunology》1983,20(5):537-547
The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H315 L315 and F315V but not with free H315, L315, V315H or V3152. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted. 相似文献
130.