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双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  相似文献   
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The aim of this study was to determine the relationship between calcium ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing ability. Semen samples remaining after preparation for standard IVF were studied in 109 patients who had sperm concentrations > or =20 x 10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected by centrifugation on a Percoll gradient. Semen analysis was performed using standard methods. Patients with higher (>50%, n = 76) fertilization rates had significantly higher ionophore-induced AR than patients with lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P < 0.05). When the data from all patients were analysed by logistic regression, only the percentage sperm motility in insemination medium and ionophore-induced AR were significantly related to fertilization rates. Similar results were also obtained when the data from a subgroup of patients with poor (<15% normal) sperm morphology were analysed. However, when patients with normal sperm morphology > or =15% were analysed separately, only sperm count and the percentage of spermatozoa with progressive motility in semen were significantly related to fertilization rates. In conclusion, ionophore- induced AR was significantly related to fertilization rates in vitro mainly in patients with teratozoospermic semen. Tests for ionophore- induced AR may provide additional information about sperm fertilizing ability but may not indicate specific defects of the physiological AR.   相似文献   
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BACKGROUND AND PURPOSE: Disseminated intravascular coagulation (DIC) is a rarely described finding in invasive pulmonary aspergillosis (IPA) with unclear impact on mortality. METHODS: This study included patients with positive cultures of Aspergillus spp. from respiratory specimens, serological evidence of aspergillosis, or lung biopsy findings supporting aspergillosis treated at National Taiwan University Hospital from January 1999 to June 2005. IPA was defined based on the consensus of the European Organization for Research and Treatment of Cancer, and the Mycosis Study Group of the National Institute of Allergy and Infectious Diseases. Univariate logistic regression analysis was used to evaluate the factors associated with mortality. RESULTS: Proven or probable IPA was diagnosed in 26 patients. Hematological malignancy was found in 11 patients (42%) and immunosuppressive agents had been administered to 17 patients (65%). Among 20 culture-proven infections (77%), the most frequently encountered fungi were Aspergillus fumigatus (46%) and Aspergillus flavus (23%). The overall mortality rate was 62%. Univariate and multivariate analyses revealed that DIC was the only factor that was significantly associated with death attributable to IPA (p<0.01). CONCLUSIONS: IPA is associated with a high mortality rate, particularly for patients with DIC.  相似文献   
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In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
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BACKGROUND AND PURPOSE: This study was conducted to investigate whether changes in the complete blood count (CBC)/differential count (DC) and C-reactive protein (CRP) were correlated to Kawasaki disease (KD) with coronary artery lesions (CALs). METHODS: A retrospective analysis was performed of all children with KD at Chang Gung Memorial Hospital at Kaohsiung from 2001 to 2006. KD patients were divided into those with and without CALs for testing of correlations with changes in CBC/DC and CRP levels. RESULTS: A total of 147 patients were enrolled for this analysis. Serial CBC/DC and CRP measurements and echocardiographic data for determination of CAL formation were obtained before and after intravenous immunoglobulin (IVIG) treatment. There were 44 (29%) KD patients having CAL formation (>3 mm in diameter of internal lumen). There was no significant difference in terms of age distribution and major diagnostic criteria between KD patients with and without CALs. Male KD patients, however, had a significantly higher rate of CAL formation (p=0.009). In multivariate logistical regression analysis, persistent monocytosis after IVIG treatment was the only factor significantly correlated to CAL formation (p=0.003). CONCLUSIONS: Of the febrile routine measurements of CBC/DC and CRP in KD, persistent monocytosis after IVIG treatment was correlated to CAL formation. Further studies to clarify the mechanism of monocytosis may help prevent the CALs of KD.  相似文献   
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A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.   相似文献   
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