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排序方式: 共有452条查询结果,搜索用时 15 毫秒
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Sequence Analysis of the RNA Polymerase Gene of Foot-and-Mouth Disease Virus Serotype Asia1 总被引:1,自引:0,他引:1
George M Venkataramanan R Pattnaik B Sanyal A Gurumurthy CB Hemadri D Tosh C 《Virus genes》2001,22(1):21-26
The complete nucleotide (nt.) sequence of the RNA polymerase (3D) gene and 81 nt. in the 3-untranslated region of foot-and-mouth disease virus (FMDV) serotype Asia1 (IND63/72) was determined and compared with the sequence of other FMDV serotypes. The 3D genomic region was 1410 nt. long encoding 470 amino acids with an inframe stop codon (TAA) at nt. position 1411–1413. The deduced amino acid sequence of the protein showed 8 conserved motifs as reported in other picornaviruses, 2 of which are 100% identical across the serotypes. Antigenic regions in the polymerase protein were predicted and found to be located at the N-terminus of the protein. The phylogenetic analysis showed that the FMD viruses were segregated into different clusters based on geographical origin; the Asia1 virus did not cluster tightly with any of the geographical groups. 相似文献
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Comparison of ultrasonographic findings in spontaneous abortions with normal and abnormal karyotypes 总被引:2,自引:2,他引:2
To determine whether ultrasonographic findings can predict the karyotype of
spontaneous abortions, 137 pregnancies (54 spontaneous, 83 assisted
ovulatory cycles) that subsequently aborted and had chromosome analysis
performed on the products of conception were studied ultrasonographically.
Transvaginal ultrasound was performed using an Acuson 128XP/10 with 7.5 MHz
probe. The numbers of empty gestational sacs, small and normal for
gestational size, embryonic poles and embryos with documented cardiac
activity were calculated. The frequency of each of these findings in
pregnancies with normal and abnormal karyotypes was compared. Of the 137
spontaneous abortions, 51 had normal chromosome analyses and 86 had
abnormal karyotypes (68 aneuploidies and 18 polyploidies). Ultrasonographic
findings in the 51 karyotypically normal pregnancies included 16 (31%) with
empty gestational sacs, and 35 (69%) with embryonic poles, of which 24
(69%) were at least 1 week smaller than expected for gestational age and 11
(31%) were the expected size. Embryonic cardiac activity was documented in
22 (63%) of the 35 embryonic poles. Amongst 86 pregnancies with abnormal
karyotypes, similar frequencies of ultrasound findings were found: 23 (27%)
with empty gestational sacs, 42 (67%) with embryonic poles smaller than
expected for gestational age, and 50 (79%) embryos lost after documentation
of embryonic cardiac activity. No differences in the frequency of
ultrasonographic findings of empty gestational sacs, small embryonic pole
and embryonic cardiac activity were observed between karyotypically normal
and abnormal spontaneous abortions. Ultrasonographic findings cannot
predict the karyotype of spontaneous abortions.
相似文献
10.
Absence of caspase 3 activation in neoplastic cells of nasopharyngeal carcinoma biopsies predicts rapid fatal outcome. 总被引:2,自引:0,他引:2
Joost J Oudejans Ahemd Harijadi Saskia A G M Cillessen Pierre Busson I Bing Tan Danny F Dukers Wim Vos Bambang Hariwiyanto Jaap Middeldorp Chris J L M Meijer 《Modern pathology》2005,18(7):877-885
Poor prognosis in nasopharyngeal carcinoma patients may result from resistance to the apoptosis-inducing effect of radio- and/or chemotherapy. Apoptosis depends on proper activation of caspase 3, resulting in cleavage of key proteins like PARP-1. To investigate whether disruption of the apoptosis pathway results in therapy-resistant tumour cells, we investigated whether absence of caspase 3 activation in tumour biopsies of nasopharyngeal carcinoma patients is related to poor clinical outcome. Moreover, we investigated whether absence of caspase 3 activation is related to loss of procaspase 3 expression or expression of the apoptosis regulators p53, bcl-2 and XIAP. We studied 36 Indonesian nasopharyngeal carcinoma patients without evidence of distant metastases who were treated with curative intent by radiotherapy only. Activation of caspase 3 and expression of the different markers were determined using specific antibodies. Levels of caspase 3 activation were determined by quantifying positively staining tumour cells. Nasopharyngeal carcinoma-derived C15 and C17 tumour cells were used as control. Absence of caspase 3 activation was strongly related to a poor clinical response to radiotherapy and to a higher T and N stage, resulting in a particularly poor clinical outcome with regard to progression-free (P<0.0001) and overall survival time (P<0.0001). Absence of caspase 3 activation was significantly correlated to loss of expression of procaspase 3 (P=0.04). In nasopharyngeal carcinoma patients treated with curative intent, absence of active caspase 3-positive neoplastic cells predicts rapid fatal outcome, and is associated with poor response to radiotherapy and high T and N stage at time of presentation. 相似文献