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51.
本文研究了唐松草新碱在水溶液中的氧化降解动力学。考查了pH值、离子强度、温度和氧含量的影响,水溶液中的氧化降解速率常数由荧光法测定。结果表明,唐松草新碱在过量氧存在下,其氧化降解反应服从假一级反应动力学方程式,速率常数可由下式表示:其速率常数主要受介质的pH值和氧含量的影响,在pH 7.2条件下没有观测到原盐效应。  相似文献   
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Venous thromboembolism (VTE) is a life-threatening complication in cancer patients. Identification of risk factors has been in focus in the past years. Functional single nucleotide polymorphisms (SNP) of coagulation factors known to influence the concentration or function may be considered to influence the risk of VTE in cancer patients. We evaluated the influence of fibrinogen plasma levels, the -455G>A SNP in the fibrinogen beta gene and the Val34Leu (163G>T) SNP in the factor XIII A-subunit (FXIII-A) gene on the risk of VTE. In 1,079 tumour patients recruited for the prospective Vienna Cancer and Thrombosis Study (CATS) fibrinogen levels were determined by the Clauss method. The FXIII-A Val34Leu and the fibrinogen -455G>A SNPs were tested by allele-specific PCR. The median follow-up time was 604 days, 83 thrombotic events occurred. The median fibrinogen level was 381 mg/dl (25th-75th percentile: 312 to 467). In a multivariable Cox model adjusted to chemotherapy, surgery, radiotherapy, age and sex, neither the fibrinogen concentration (hazard ratio [HR] =1.05, confidence interval [CI] 0.839-1.310 p=0.68), nor the -455G>A SNP (HR=0.77, 95%CI 0.491-1.197; p=0.24), nor the Val34Leu SNP (HR=0.99, 95%CI 0.646-1.542 p=0.99) were associated with occurrence of VTE. The fibrinogen concentration was not significantly different among the fibrinogen -455G or A genotype carriers (p = 0.33). Disseminated intravascular coagulation was observed in only five patients, none of these developed VTE. In conclusion, fibrinogen plasma levels, the fibrinogen -455G>A and the FXIII-A Val34Leu polymorphisms were not associated with VTE in our study.  相似文献   
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Purpose  Malignant high-grade gliomas are the most common secondary neoplasms in children cured of acute lymphoblastic leukaemia (ALL). Although many predisposing factors exist (including systemic or intrathecal chemotherapy, young age, brain infiltration and genetic predispositions), cranial irradiation appears to be the strongest one. Methods  Three cases of secondary high-grade gliomas (two multiform glioblastomas, grade IV; one anaplastic astrocytoma, grade III) developed in ALL survivors (F–M, 1:2) 3 to 6.3 years after stopping ALL therapy according to BFM-90 trial. Results  All tumours were supratentorial, contrast-enhancing, space-occupying, highly advanced and aggressive. Possible risk factors and current therapeutic options for paediatric ALL and malignant gliomas are reviewed and discussed. Conclusions  Prognosis in secondary malignant gliomas in children is poor (overall survival of 5, 10 and 19 months) despite intense therapy. Thus, protocols for paediatric ALL reduce prophylactic cranial irradiation in favour of intrathecal and intravenous high-dose MTX. Nevertheless, ALL survivors must undergo systematic, long-term surveillance for early detection of intracranial neoplasms.  相似文献   
54.
Titelbaum  DS; Hayward  JC; Zimmerman  RA 《Radiology》1989,173(3):663-667
Studies of 23 pediatric patients with pachygyriclike changes (PLCs) examined with computed tomography (CT) and magnetic resonance (MR) imaging were reviewed to determine topographic patterns and correlate them with various clinical syndromes and degrees of neurologic impairment. Three types of topographic distributions were identified: unilateral, diffuse, and bilateral nondiffuse (of which eight of 10 showed frontotemporal predominance). PLCs were an isolated finding in seven patients, were associated with various congenital syndromes in nine patients, and were associated with congenital infection in seven patients, six of whom showed marked white matter abnormalities. Although most patients had severe developmental delay, three with nondiffuse PLCs had less severe impairment, permitting less required care.  相似文献   
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Gemcitabine has demonstrated single-agent efficacy in the treatment of advanced breast cancer, with response rates of up to 42%. The agent is well tolerated, with relatively mild side effects, and has limited overlapping toxicities with other drugs used in combination chemotherapy for breast cancer. It is, therefore, a good candidate for inclusion in multidrug regimens for the treatment of this disease. This article reviews results of gemcitabine/anthracycline-containing double- and triple-drug combinations used to treat patients with early-stage and advanced breast cancer. Results from phase I and II trials were promising, with good tolerability and overall response rates ranging from 33%-89% in advanced disease and up to 95% in the neoadjuvant treatment of early-stage disease. A phase III trial is currently comparing gemcitabine/epirubicin/paclitaxel and 5-fluorouracil/epirubicin/cyclophosphamide in patients with advanced breast cancer. Preliminary toxicity data on 78 patients show that both regimens were well tolerated, with similar incidences of treatment-related effects. Additional comparative studies of gemcitabine-containing drug regimens in breast cancer are warranted.  相似文献   
58.
BACKGROUND: Brain metastases have evolved from a rare to a frequently encountered event in advanced breast cancer due to advances in palliative systemic treatment. PATIENTS AND METHODS: All Patients treated at our centre from 1994 to 2004 with WBRT for brain metastases from breast cancer were included. We performed a multivariate analysis (Cox regression) to explore which factors are able to influence significantly cerebral time to progression (TTP) and overall survival (metastatic sites [visceral versus non-visceral], Karnofsky performance score [KPS], age, intensified local treatment [boost irradiation, neuro-surgical resection] further systemic treatment). RESULTS: Overall 174 patients, median age 51 years, range 27-76 years, were included. Median TTP was 3 months (m), range 1-33+ m. Median overall survival was 7 m, range 1-44 m. Factors significantly influencing TTP were KPS (p = 0.002), intensified local treatment (p < 0.001), and palliative systemic treatment (p = 0.001). Factors significantly influencing survival were intensified local treatment (p = 0.004), metastatic sites (p = 0.008), KPS (p = 0.006), and palliative systemic treatment (p < 0.001). CONCLUSION: As shown by the significant influence of metastatic sites, some patients die from their advanced systemic tumour situation before they would die from cerebral progression. In other individuals however, intensified local treatment and systemic treatment appear to influence cerebral time to progression and overall survival.  相似文献   
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OBJECTIVE: To examine the characteristics of infants suffering from failure to thrive in a community based cohort in Israel and to ascertain the effect of failure to thrive on their cognitive development. METHODS: By review of records maintained at maternal and child health clinics in Jerusalem and the two of Beit Shemesh, epidemiological data were obtained at age 15 months on a cohort of all babies born in 1991. For each case of failure to thrive, a matched control was selected from the same maternal and child health clinic. At age 20 months, cognitive development was measured, and at 25 months a home visit was carried out to assess maternal psychiatric status by questionnaire, and the HOME assessment was performed to assess the home environment. RESULTS: 3.9% of infants were found to have fallen below the third centile in weight for at least three months during the first year of life. Infants with failure to thrive did not differ from the general population in terms of obstetric or neonatal complications, birth order, or parents' ethnic origin, age, or years of education. The infants with failure to thrive did have lower birthweights and marginally smaller head circumferences at birth. Developmental assessment at 20 months of age showed a DQ of 99.7 v 107.2 in the matched controls, with 11.5% having a DQ below 80, as opposed to only 4.6% of the controls. No differences were found in maternal psychiatric problems as measured by a self report questionnaire. There were, however, significant differences in subscales of the HOME scale. CONCLUSIONS: (1) Infants who suffered from failure to thrive had some physiological predispositions that put them at risk; (2) failure to thrive may be an early marker of families providing suboptimal developmental stimulation.  相似文献   
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