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One hundred eighty-one patients with measurable recurrent or metastatic colorectal cancer, who had not received prior chemotherapy, were randomized in a prospective controlled trial to receive 5-fluorouracil (5FU), 13.5 mg/kg, for five days (arm A) or high-dose folinic acid [Cyanamid-Lederle, Italy] (FA), 200 mg/m2, for five days and 5FU, 400 mg/m2 for five days (arm B). The treatments were repeated every four weeks. One hundred fifty-five patients were evaluable for response. The two arms were balanced for all potential prognostic factors studied. The response rate (CR+PR) was 18% in the 5FU arm and 16% in the 5FU plus FA arm. Median duration of response was 56 weeks for 5FU alone and 42 weeks for the combination (p = 0.48). Median time to failure (TTF) was 20 weeks for arm A and 21 for arm B (p = 0.62). Median survival was 62 weeks on the 5FU arm and 53 weeks on the FA plus 5FU arm (p = 0.14). Dose intensity (DI) delivered was the same in both arms. Diarrhea and mucositis were the most frequent adverse reactions in arm B; 20% of the patients in arm A and 38% of those in arm B experienced diarrhea (p = 0.008). Mucositis occurred in 34% of patients in arm A and 42% in arm B (p = 0.04). In general nausea and vomiting were moderate. Hematological toxicity was more severe in patients treated with 5FU alone: 31% in arm A and 14% in arm B developed leukopenia (p = 0.015). In the combination arm one patient died due to gastrointestinal and hematological toxicity after the seventh cycle. This study indicates that, in advanced colorectal cancer, the combination of high-dose FA and 5FU is not superior to 5FU alone when utilized at standard high-dose intensity.  相似文献   
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目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。  相似文献   
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A total of 1292 sera, provided by different USLs (Local Health Centers) in the Marche Region (Italy), was tested by ELISA and Western Blot for the detection of anti-HTLV I/II ad HIV-1 antibodies. It was decided not to follow any particular criterion when collecting the sera, so no protocol of admission was established in advance. Of the 1292 sera tested, 12 were found antibody positive to HTLV I/II, 18 to HIV-1 and 4 to both viruses. Of the seropositives, for HTLV I/II and HIV-1, respectively, 2 and 3 were prisoners; 2 and 4 were IVDAs, 3 and 7 were hematological patients, 3 and 2 were hospitalized subjects (not for hematological disorders), and 2 and 2 were positives belonging to a healthy population group. These data suggest that the viruses may also be spreading among groups other than the high-risk ones (homosexuals, IVDAs, prisoners, blood-transfusion recipients, promiscuous heterosexuals).  相似文献   
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The separate effects of energy restriction and weight loss on serum lipids were studied in 24 postmenopausal moderately obese women before and after weight loss of greater than 10 kg to normal weight. Fasting serum triglycerides (TGs), total cholesterol (TC), high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) cholesterol, and insulin were measured at the end of four 10-d in-hospital phases, two before and two after weight loss: phase I, stable weight; phase II, 3350 kJ/d(800 kcal/d), followed by outpatient weight loss; phase III, 3350 kJ/d (800 kcal/d); and phase IV, stable weight. Diet composition and exercise were constant the entire study. Energy-restriction effect was determined by comparing average values in stable-weight phases (I and IV) with low-energy phases (II and III); weight-loss effect was determined by comparing values in obese phases (I and II) with reduced-weight phases (III and IV). Energy restriction lowered TG, TC, LDL cholesterol, the LDL-HDL cholesterol ratio, and insulin and raised HDL cholesterol (all P less than 0.05). Weight loss lowered TG, TC, LDL cholesterol, and insulin (all P less than 0.01) but did not change HDL cholesterol or the LDL-HDL cholesterol ratio. The results suggest that reduction to a weight-steady nonobese state significantly lowers TG, TC, and LDL cholesterol but does not improve HDL cholesterol or the LDL-HDL cholesterol ratio.  相似文献   
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Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.   相似文献   
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Firearms and suicide in the United States.   总被引:7,自引:4,他引:3       下载免费PDF全文
Regional United States suicide rates in the mid 1970s were associated with the household prevalence of all guns and of pistols. The term "regional" applies to the nine Census divisions of the four US census regions. A literature review suggests that the relation may be etiologic, and that more definitive studies and pilot programs are needed. Arming may be an etiologic factor common both to individual and to national self-destructive behaviors.  相似文献   
10.
Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening.  相似文献   
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