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51.
PURPOSE: To investigate the efficacy and toxicity of oxaliplatin, a diaminocyclohaxane platinum derivative with incomplete cross-resistance to cisplatin in patients with relapsed or cisplatin-refractory germ cell cancer. PATIENTS AND METHODS: Thirty-two patients with nonseminomatous cisplatin-refractory germ cell cancer or relapsed disease after high-dose chemotherapy (HDCT) plus autologous stem-cell support were treated with single-agent oxaliplatin 60 mg/m(2) on days 1, 8, and 15 repeated every 4 weeks (group 1; n = 16) or oxaliplatin 130 mg/m(2) given on days 1 and 15 of a 4-week cycle (group 2; n = 16). Patients were pretreated with a median of seven (range, three to 13) cisplatin-containing treatment cycles; 78% had received carboplatin/etoposide-based HDCT before oxaliplatin therapy. Twenty-seven patients (84%) were considered refractory (n = 20; 63%) or absolutely refractory (n = 7; 22%) to cisplatin therapy. RESULTS: Overall, four patients achieved a partial remission (13%; 95% confidence interval, 1% to 24%). Two additional patients achieved disease stabilization. All responses were observed in cisplatin-refractory patients, including three who had not responded to previous HDCT. Patients received a median two cycles of oxaliplatin with a median cumulative dose of 350 mg/m(2). Hematologic toxicity was generally mild, with five patients developing grade 3/4 thrombocytopenia. Nonhematologic side effects consisted mainly of nausea/vomiting. One patient developed grade 3 neurotoxicity. CONCLUSION: Considering the particularly unfavorable prognostic characteristics of this patient population compared with patients from previous trials for new drugs in germ cell cancer, eg, paclitaxel and gemcitabine, a 13% overall response rate and a 19% response rate in the group treated with oxaliplatin 130 mg/m(2) seems to be of interest. Oxaliplatin may be a palliative treatment option for this patient population, and evaluation in combination regimens is warranted.  相似文献   
52.
Distributions of adducts formed from each of the four optically active isomers of 3,4-dihydroxy-1,2-epoxy-1,2,3, 4-tetrahydrobenzo[c]phenanthrene and of 7,8-dihydroxy-9,10-epoxy-7,8, 9,10- tetrahydrobenzo[a]pyrene (BcPh and BaP diol epoxides) on reaction with an equimolar mixture of deoxyadenosine and deoxyguanosine 5'-monophosphates were compared with the known adduct distributions from these diol epoxides (DEs) upon reaction with calf thymus DNA in vitro. In the presence of an equimolar (100 mM total) mixture of dAMP and dGMP, the efficiency of formation of all types of adducts relative to tetraols is comparable for both the BaP ( approximately 40-60%) and BcPh ( approximately 30-40%) diol epoxides. This is in contrast to the partitioning between tetraols and adducts observed with DNA, where the BcPh DEs form adducts much more efficiently than the BaP DEs. Preference for trans versus cis ring opening by the exocyclic amino groups of the free nucleotides in the dAMP/dGMP mixture is greater for the DE diastereomer in which the benzylic hydroxyl group and the epoxide oxygen are trans (DE-2). This is qualitatively similar to the preferences for trans versus cis adduct formation on reaction of these isomers with DNA, as well as trans versus cis tetraol formation on their acid hydrolysis. For the BcPh DE isomers, competitive reaction between dGMP and dAMP gives 40-62% of the total exocyclic amino group adducts as dA adducts. A similar distribution of dG versus dA adducts had previously been observed on reaction of the BcPh DEs with DNA, except in the case of (+)-3(R),4(S)-dihydroxy-1(R),2(S)-epoxy-1,2,3, 4-tetrahydrobenzo[c]phenanthrene, which gives approximately 85% dA adducts on reaction with DNA. With the BaP DEs, 60-77% of the exocyclic amino group adducts formed upon competitive reaction with the free nucleotides are derived from dGMP. The observed dG selectivity of these BaP DEs is much smaller with the nucleotide mixture than it is with DNA, leading to the conclusion that DNA structure has a much larger modifying effect on the base selectivity of the BaP relative to the BcPh DEs.  相似文献   
53.
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
54.
A 69-year-old man who had a left pneumonectomy for nonsmall cell lung cancer had a bronchopulmonary fistula develop that recurred after surgical closure. He had multiple organ failure develop precluding further operative intervention. Successful resolution of the fistula was achieved using a novel application of a covered expandable metallic stent.  相似文献   
55.
Background: Co-morbidity, or the presence of more than one clinical condition, is gaining increased attention in epidemiological and health services research. However, the clinical relevance of co-morbidity has yet to be defined. In general practice, few studies have been conducted into co-morbidity, either at a single health care encounter, an episode of care, or for a defined time period. Aims: To describe the major co-morbidity cluster profiles recorded by general practitioners. Another aim of this study is to describe the common clusters of co-prescribing. Methods and results: Twelve month data from patients attending 156 GPs from 95 practices around a six month period of January to June 2003 were analysed. This represented 840 961 encounters from about 200 000 individual patients at these participating practices. Co-morbidity and co-prescribing cluster profiles are represented by problems managed and reasons for prescribing for the top 10 presentations and top 10 prescribed drugs in the study period. Conclusions: By analysing the 10 most prevalent problems and 10 most prevalent drugs prescribed in consultations in a community sample, other co-morbidities that are particular to general practice, for example hypertension and lipid disorders, can be uncovered. Whether these clusters are causally related or occur by chance requires further analysis.  相似文献   
56.
Low birth weight, a marker of adverse intrauterine circumstances, is known to be associated with a range of disease outcomes in later life, including coronary heart disease, hypertension, type 2 diabetes, and osteoporosis. However, it may also decrease the risk of other common conditions, most notably neoplastic disease. The authors describe the associations between birth weight, infant weight gain, and a range of mortality outcomes in the Hertfordshire Cohort. This study included 37,615 men and women born in Hertfordshire, United Kingdom, in 1911-1939; 7,916 had died by the end of 1999. For men, lower birth weight was associated with increased risk of mortality from circulatory disease (hazard ratio per standard deviation decrease in birth weight = 1.08, 95% confidence interval: 1.04, 1.11) and from accidental falls but with decreased risk of mortality from cancer (hazard ratio per standard deviation decrease in birth weight = 0.94, 95% confidence interval: 0.90, 0.98). For women, lower birth weight was associated with a significantly (p < 0.05) increased risk of mortality from circulatory and musculoskeletal disease, pneumonia, injury, and diabetes. Overall, a one-standard-deviation increase in birth weight reduced all-cause mortality risk by age 75 years by 0.86% for both men and women.  相似文献   
57.
Although the cause of autism is undetermined, a general consensus has been that some type of early aberrant neural development underlies the disorder. Given the increased prevalence of macrocephaly in autism, one theory of abnormal neural development implicates early brain growth resulting in larger brain and head size in autism. Surface area measurements of the midsagittal section of the corpus callosum can be used as an index of neural development and white-matter integrity because the corpus callosum is the major white-matter structure that interconnects the two cerebral hemispheres. The purpose of this study was to obtain corpus callosum surface area, shape, and contour in a sample of non-mentally retarded autistic subjects with macrocephaly (n = 12) and compare them with those of matched (n = 8), typically developing control subjects with benign macrocephaly. No significant differences were found in surface area, shape, or contour between groups, nor did corpus callosum surface area relate to measures of IQ or picture vocabulary. These findings suggest no unique difference in overall regional corpus callosum surface area in autism with macrocephaly.  相似文献   
58.
59.
Purpose Activating Flt3 mutations are observed in about 30% of patients with acute myeloid leukaemia (AML) and individual Flt3 mutations are applicable for minimal residual disease (MRD) analyses.Methods We investigated the MRD status in four AML patients carrying different Flt3 mutations (three patients with Flt3 length mutations of the juxtamembrane domain, one patient carrying a mutation of the Flt3 tyrosine kinase domain, i.e. Flt3-TKD mutation) who underwent allogeneic peripheral blood stem cell transplantation (PBSCT). Residual leukaemia cells were retrospectively determined by real-time PCR at different time points.Results We can demonstrate a good correlation between the course of MRD status and clinical events in all four investigated patients.Conclusion These examples demonstrate the potential impact of Flt3 based MRD status not only after but also prior to allogeneic PBSCT.  相似文献   
60.
OBJECTIVE: To assess if the angiogenic factors vascular endothelial growth factor (VEGF) and D-dimer are predictive of persistent disease, early relapse, and survival in patients with ovarian cancer who achieve a complete clinical remission after first-line chemotherapy. METHODS: Serum levels of VEGF and D-dimer were assessed by ELISA in 62 patients who completed first-line chemotherapy and underwent second-look laparotomy at Duke University Medical Center. Cox Proportional Hazards Modeling was utilized to determine if VEGF and/or D-dimer levels could predict disease-free and overall survival. The Kaplan-Meier method was used to estimate median survival. The Wilcoxon test was used to determine if a significant difference existed in median VEGF and D-dimer levels between patients with positive and negative second-look operations. RESULTS: Forty (65%) of the 62 women who underwent second-look laparotomy had persistent disease. The median VEGF levels were 264 pg/ml (range 109-896 pg/ml) in the group with negative second looks compared to 390 pg/ml (range 99-1011 pg/ml) in those with positive second-looks (P = 0.1). High levels of VEGF were marginally associated with the presence of persistent (P = 0.10) and gross (P = 0.07) disease at the time of second look laparotomy. After adjusting for CA125, women with high VEGF serum levels had a worse overall survival (P = 0.004). CONCLUSIONS: This study suggests that serum VEGF may be a clinically important marker for persistent disease and is predictive of survival in ovarian cancer patients after first-line chemotherapy.  相似文献   
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