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We describe a simple fluorometric method for determining aluminum in serum samples by monitoring the rate of reaction of 2-hydroxy-1-naphthaldehyde-p-methoxybenzoylhydrazone with aluminum ions. The emission of the resulting fluorescent metal-chelate formed is measured at 475 nm. Aluminum was measured in the supernate of serum after proteins were removed by precipitation with concentrated nitric acid, and calculations were based on the technique of standard additions. Within-run precision (CV) was 7.8% and 4.8% at mean aluminum concentrations of 7.7 and 60.7 micrograms/L, respectively (n = 10); between-run precision (CV) was 8.9% and 5.7% at mean aluminum concentrations of 23.3 and 46.8 micrograms/L, respectively (n = 10). The standard curve for the method is linear over the range of 0-250 micrograms of aluminum per liter. Samples from 49 patients were analyzed for aluminum by the proposed method (y) and by electrothermal atomic absorption spectroscopy (x). Linear regression analysis of the results yielded the equation y = 0.98x + 2.3 (r = 0.989, Syx = 6.7). The proposed method is comparable in sensitivity to the well-accepted atomic absorption spectrometric method but is simpler and less expensive.  相似文献   
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Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.  相似文献   
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Segel  MC; Paulus  DD; Hortobagyi  GN 《Radiology》1988,169(1):49-54
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer.  相似文献   
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AIM: The G20210A mutation of the prothrombin gene is a genetic risk factor for venous thromboembolism (VTE). Variability exists in the mutation prevalence in both normal individuals and VTE patients. The aim of this study was to determine the mutation prevalence in Northwestern Greece and evaluate its association with VTE. METHODS: Presence of the G20210A mutation was investigated using DNA analysis in 176 consecutive patients with a history of venous thrombosis or pulmonary embolism and in 300 healthy controls, all Caucasian residents of Northwestern Greece. RESULTS: The mutation was present 12 patients (6.8%) and 8 controls (2.7%). The odds ratio for presence of the mutation versus the normal genotype in VTE was 2.7 (95% CI: 1.1 to 6.7), which was statistically significant. The prevalence of the G20210A prothrombin gene mutation in Northwestern Greece is 2.7% (95% CI: 0.8% to 4.4%) with an allele frequency of 1.3% (95% CI: 0.4% to 2.3%). CONCLUSION: The G20210A mutation of the prothrombin gene is associated with VTE in the Caucasian residents of this geographic region.  相似文献   
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A randomized trial was conducted to compare the efficacy and safety of fluconazole versus that of amphotericin B in the treatment of candidemia in non-neutropenic adults. Enrollment was stratified by disease severity (APACHE II score). Patients were randomized (1:1) to receive amphotericin B 0.6 mg/kg/day (cumulative dose 8 mg/kg) or fluconazole 800 mg intravenous loading dose, then 400 mg daily for four weeks (intravenous for at least 10 days). Patients were monitored for six months. A total of 106 patients were enrolled. A protocol amendment implemented midway through the trial required patients to be removed from the study and treated with amphotericin B if species identification indicated candidemia due toCandida glabrata orCandida krusei. Baseline characteristics were similar for the two groups; 103 patients (fluconazole, 50; amphotericin B, 53) met the major enrollment criteria. The intention-to-treat analysis indicated successful therapy in 50% of fluconazole recipients compared to 58% of the amphotericin B group (p=0.39; one-sided 95% Cl, –8 to 24%). The efficacy analysis included 84 patients (fluconazole, 42; amphotericin B, 42); successful outcomes were observed in 57% and 62% of cases in the fluconazole and amphotericin B groups, respectively (p=0.66: one-sided 95% Cl, –12 to 22%). The mortality at day 14 for the fluconazole group was 26% and for the amphotericin B group 21% (p=0.52; chi-square test) and remained similar throughout the course of follow-up. Drug-related adverse events were more frequent with amphotericin B than with fluconazole and prompted switching of therapy for two (4%) and zero cases, respectively. Fluconazole and amphotericin B were associated with similar clinical response rates and survival in the treatment of candidemia among non-neutropenic patients; however, drug-related adverse events were more frequent with amphotericin B.  相似文献   
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