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排序方式: 共有350条查询结果,搜索用时 15 毫秒
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Although stimulated [3H] inositol phosphate turnover has been demonstrated in isolated, perfused [3H] inositol prelabelled rat hearts, there is still no information regarding Ins (1,4,5)P3 levels in intact cardiac muscle. Using a D-myo-Ins(1,4,5)P3 assay system, Ins(1,4,5)P3 levels were determined in isolated perfused rats hearts during ischaemia, reperfusion and alpha 1-adrenergic stimulation via noradrenaline (3 x 10(-5) M). Control hearts contained +/- 674 pmols Ins(1,4,5)P3/g dry heart weight. Myocardial Ins(1,4,5)P3 levels were significantly decreased (+/- 389 pmols/g dry heart weight) after exposure to 20 mins of normothermic ischaemic cardiac arrest (NICA). Reperfusion produced a marked increase in Ins(1,4,5,)P3 levels (+/- 1,115 pmols/g dry heart weight) after only 30 s. Noradrenaline caused a 3-4 fold increase in tissue Ins(1,4,5)P3 levels within 30 s. After 20 mins stimulation with noradrenaline, the Ins(1,4,5)P3 levels were still significantly elevated. The rise in tissue Ins(1,4,5)P3 levels during reperfusion as well as during noradrenaline administration was counteracted by neomycin (0.5 x 10(-3) M), an inhibitor of phosphoinositidase specific phospholipase C. In both events neomycin restored the Ins(1,4,5)P3 levels to control values. For correlation of tissue Ins(1,4,5)P3 levels with mechanical events, noradrenaline (3 x 10(-5) M), in the presence of 10 mM LiCl, 10(-7) M propranolol and 10(-7) M atropine, was administered to isolated perfused rat hearts and the mechanical performance recorded over a period of 20 mins. Noradrenaline caused a significant increase in peak systolic pressure and work performance which was maintained for at least 10 mins, suggesting that the positive inotropic effects of noradrenaline may be provoked by Ins(1,4,5)P3. Furthermore, the finding that 20 min NICA followed by 30 s reperfusion causes an immediate significant increase in Ins(1,4,5)P3 content suggests a role for the phosphatidylinositol pathway in the intracellular Ca2+ overloading, characteristic of ischaemia-reperfusion. 相似文献
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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
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van Leth F Huisamen CB Badaro R Vandercam B de Wet J Montaner JS Hall DB Wit FW Lange JM;NN Study Group 《Journal of acquired immune deficiency syndromes (1999)》2005,38(3):296-300
BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy. 相似文献