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A six year randomised trial was conducted among 5139 apparently healthy male doctors to see whether 500 mg aspirin daily would reduce the incidence of and mortality from stroke, myocardial infarction, or other vascular conditions. Though total mortality was 10% lower in the treated than control group, this difference was not statistically significant and chiefly involved diseases other than stroke or myocardial infarction. Likewise, there was no significant difference in the incidence of non-fatal myocardial infarction or stroke—indeed, disabling strokes were somewhat commoner among those allocated aspirin. The lower confidence limit for the effect of aspirin on non-fatal stroke or myocardial infarction, however, was a substantial 25% reduction. Migraine and certain types of musculoskeletal pain were reported significantly less often in the treated than control group, but as the control group was not given a placebo the relevance of these findings was difficult to assess. There was no apparent reduction in the incidence of cataract in the treated group.The lack of any apparent reduction in disabling stroke or vascular death contrasts with the established value of antiplatelet treatment after occlusive vascular disease.  相似文献   
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Murine erythroleukaemic cells were studied to determine whether different isoferritins have different functions. The cells were labelled with radioactive iron and the pattern of isoferritins was analysed by chromatofocussing. No change was found after iron-loading the cells but after inducing erythroid differentiation with dimethyl sulphoxide (DMSO), iron was incorporated into both more basic and more acidic isoferritins. This was compared to ferritin subunit synthesis; DMSO induced the synthesis of a third, minor subunit whereas iron-loading had no effect. The fate of murine erythroleukaemic cell ferritin iron was followed after incubations in iron-deficient medium containing DMSO; some, but not all, of the ferritin iron was mobilized and used for haem synthesis, and the remaining iron was found amongst the more basic isoferritins. Finally, sequential radioactive iron labels were used to demonstrate that the movement of iron from ferritin to haem was compatible with the 'last-in-first-out' principle, but this could not be related to different isoferritins. These results show firstly that DMSO changes the pattern of isoferritins and ferritin subunits in murine erythroleukaemic cells. Secondly, iron associated with more basic isoferritins seems to be less easily mobilized for haem synthesis. These results support the concept that different isoferritins have different functions.  相似文献   
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OBJECTIVE--To assess the hazards associated with long term use of tobacco. DESIGN--Prospective study of mortality in relation to smoking habits assessed in 1951 and again from time to time thereafter, with causes sought of deaths over 40 years (to 1991). Continuation of a study that was last reported after 20 years'' follow up (1951-71). SUBJECTS--34,439 British male doctors who replied to a postal questionnaire in 1951, of whom 10,000 had died during the first 20 years and another 10,000 have died during the second 20 years. RESULTS--Excess mortality associated with smoking was about twice as extreme during the second half of the study as it had been during the first half. The death rate ratios during 1971-91 (comparing continuing cigarette smokers with life-long non-smokers) were approximately threefold at ages 45-64 and twofold at ages 65-84. The excess mortality was chiefly from diseases that can be caused by smoking. Positive associations with smoking were confirmed for death from cancers of the mouth, oesophagus, pharynx, larynx, lung, pancreas, and bladder; from chronic obstructive pulmonary disease and other respiratory diseases; from vascular diseases; from peptic ulcer; and (perhaps because of confounding by personality and alcohol use) from cirrhosis, suicide, and poisoning. A negative association was confirmed with death from Parkinson''s disease. Those who stopped smoking before middle age subsequently avoided almost all of the excess risk that they would otherwise have suffered, but even those who stopped smoking in middle age were subsequently at substantially less risk than those who continued to smoke. CONCLUSION--Results from the first 20 years of this study, and of other studies at that time, substantially underestimated the hazards of long term use of tobacco. It now seems that about half of all regular cigarette smokers will eventually be killed by their habit.  相似文献   
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During January 1968 to December 1972, 133 patients with advanced Hodgkin''s disease (HD) were admitted to hospital for combination chemotherapy with mustine, vinblastine, procarbazine, and prednisolone (MVPP regimen). Remission rates were 76% among 49 untreated patients and 90% among 42 patients who had relapsed after radiotherapy. The corresponding five-year survival rates were 65% and 86% respectively. Provided the observed yearly mortality (6%) remains unchanged 75% of patients who had previously received no treatment or irradiation and achieved remission are expected to continue in first remission after five years. Forty-two patients had received prior chemotherapy. They had lower remission and five-year survival rates (40% and 33% respectively), and fewer than half of those achieving remission were still in first remission after five years. There were several reasons for the poor prognosis in this group, including advanced-stage disease (stage IVB), age over 40, and achievement of remission.Chemotherapy was administered on an outpatient basis. Haematological toxicity and immediate drug-related side effects were similar to those of other regimens but there was no appreciable neurotoxicity. Most deaths were due to either HD itself or complications of advanced disease. Five malignancies other than HD occurred in patients who had received both single-agent chemotherapy and radiotherapy before MVPP chemotherapy. Two patients developed osteonecrosis of the femoral heads.Combination chemotherapy has a profound effect on the prognosis of advanced HD. The MVPP regimen yields results comparable to those of other regimens but with perhaps less toxicity.  相似文献   
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The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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To date, very large scale sequencing of many clinically important RNA viruses has been complicated by their high population molecular variation, which creates challenges for polymerase chain reaction and sequencing primer design. Many RNA viruses are also difficult or currently not possible to culture, severely limiting the amount and purity of available starting material. Here, we describe a simple, novel, high-throughput approach to Norovirus and Hepatitis C virus whole genome sequence determination based on RNA shotgun sequencing (also known as RNA-Seq). We demonstrate the effectiveness of this method by sequencing three Norovirus samples from faeces and two Hepatitis C virus samples from blood, on an Illumina MiSeq benchtop sequencer. More than 97% of reference genomes were recovered. Compared with Sanger sequencing, our method had no nucleotide differences in 14,019 nucleotides (nt) for Noroviruses (from a total of 2 Norovirus genomes obtained with Sanger sequencing), and 8 variants in 9,542 nt for Hepatitis C virus (1 variant per 1,193 nt). The three Norovirus samples had 2, 3, and 2 distinct positions called as heterozygous, while the two Hepatitis C virus samples had 117 and 131 positions called as heterozygous. To confirm that our sample and library preparation could be scaled to true high-throughput, we prepared and sequenced an additional 77 Norovirus samples in a single batch on an Illumina HiSeq 2000 sequencer, recovering >90% of the reference genome in all but one sample. No discrepancies were observed across 118,757 nt compared between Sanger and our custom RNA-Seq method in 16 samples. By generating viral genomic sequences that are not biased by primer-specific amplification or enrichment, this method offers the prospect of large-scale, affordable studies of RNA viruses which could be adapted to routine diagnostic laboratory workflows in the near future, with the potential to directly characterize within-host viral diversity.  相似文献   
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Background

Influenza B viruses can cause morbidity and mortality in humans but due to the lack of an animal reservoir are not associated with pandemics. Because of this, there is relatively limited genetic sequences available for influenza B viruses, especially from developing countries. Complete genome analysis of one influenza B virus and several gene segments of other influenza B viruses isolated from Uganda from May 2009 through December 2010 was therefore undertaken in this study.

Methods

Samples were collected from patients showing influenza like illness and screened for influenza A and B by PCR. Influenza B viruses were isolated on Madin-Darby Canine Kidney cells and selected isolates were subsequently sequenced and analyzed phylogenetically.

Findings

Of the 2,089 samples collected during the period, 292 were positive by PCR for influenza A or B; 12.3% of the PCR positives were influenza B. Thirty influenza B viruses were recovered and of these 25 that grew well consistently on subculture were subjected to further analysis. All the isolates belonged to the B/Victoria-lineage as identified by hemagglutination inhibition assay and genetic analysis except one isolate that grouped with the B-Yamagata-lineage. The Ugandan B/Victoria-lineage isolates grouped in clade 1 which was defined by the N75K, N165K and S172P substitutions in hemagglutinin (HA) protein clustered together with the B/Brisbane/60/2008 vaccine strain. The Yamagata-like Ugandan strain, B/Uganda/MUWRP-053/2009, clustered with clade 3 Yamagata viruses such as B/Bangladesh/3333/2007 which is characterized by S150I and N166Y substitutions in HA.

Conclusion

In general there was limited variation among the Ugandan isolates but they were interestingly closer to viruses from West and North Africa than from neighboring Kenya. Our isolates closely matched the World Health Organization recommended vaccines for the seasons.  相似文献   
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