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1.
Lung carcinoma development is accompanied by field changes that may have diagnostic significance. We have previously shown the importance of chromosomal aneusomy in lung cancer progression. Here, we tested whether genomic gains in six specific loci, TP63 on 3q28, EGFR on 7p12, MYC on 8q24, 5p15.2, and centromeric regions for chromosomes 3 (CEP3) and 6 (CEP6), may provide further value in the prediction of lung cancer. Bronchial biopsy specimens were obtained by LIFE bronchoscopy from 70 subjects (27 with prevalent lung cancers and 43 individuals without lung cancer). Twenty six biopsies were read as moderate dysplasia, 21 as severe dysplasia and 23 as carcinoma in situ (CIS). Four-micron paraffin sections were submitted to a 4-target FISH assay (LAVysion, Abbott Molecular) and reprobed for TP63 and CEP 3 sequences. Spot counts were obtained in 30–50 nuclei per specimen for each probe. Increased gene copy number in 4 of the 6 probes was associated with increased risk of being diagnosed with lung cancer both in unadjusted analyses (odds ratio = 11, p<0.05) and adjusted for histology grade (odds ratio = 17, p<0.05). The most informative 4 probes were TP63, MYC, CEP3 and CEP6. The combination of these 4 probes offered a sensitivity of 82% for lung cancer and a specificity of 58%. These results indicate that specific cytogenetic alterations present in preinvasive lung lesions are closely associated with the diagnosis of lung cancer and may therefore have value in assessing lung cancer risk.  相似文献   
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Several dinoflagellate strains of the genus Pfiesteria were isolated by culturing techniques from sediment samples taken in the Oslofjord region of Norway. Pfiesteria piscicida, well known as a fish killer from the Atlantic coast of America, was identified by genetic methods and light microscopy. The related species Pfiesteria shumwayae was attracted from the sediment by the presence of fish, and has proved toxic. This present survey demonstrates the wide distribution of these potentially harmful species, but so far they have not been connected with fish kills in Europe.  相似文献   
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SUMMARY

Cholesterol oxidation products have been demonstrated to possess a wide variety of biological properties and have been implicated in playing an important role in the development of atherosclerosis. We have developed an analytical method using capillary gas chromatography-mass spectrometry (GC-MS) for the analysis of cholesterol oxidation products in low-density lipoprotein (LDL). The method uses programmed multiple selected ion monitoring (SIM), providing enhanced sensitivity and accuracy of peak detection over full-scan mass spectra. The major oxidation products of cholesterol in oxidized LDL were identified as 7β-hydroxy-cholesterol and 7-keto-cholesterol. Minor products included 4β-hydroxy-cholesterol, 6β-hydroxy-cholesterol and cholesterol-5α,6α-epoxide. Native LDL contains 7-lathosterol, which is a biosynthetic precursor of cholesterol, as well as low levels of 7β-hydroxy-cholesterol and 7-keto-cholesterol. 7-Lathosterol was not detected in oxidized LDL. A time course oxidation of native LDL with 8 μM CuCl2 demonstrated a rapid increase in 7β-hydroxy-cholesterol and 7-keto-cholesterol over the first 4 h. Cholesterol—5α,6α-epoxide, and β4-hydroxy- and 6β-hydroxy-cholesterol levels increased gradually, while 7-lathosterol decreased over the same period. This method was used to measure the levels of 7-lathosterol and cholesterol oxides in the LDL of 20 healthy subjects in order to establish the mean concentration and a reference range. This method can be used for the characterization and quantitation of oxysterols in native and oxidized LDL and may afford an additional index of oxidative modification of plasma lipoproteins.  相似文献   
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Deoxyuridine triphosphatase has been purified from cultured human lymphoid cells in high yield and stable form by a relatively simple procedure. The properties differed somewhat from those reported previously, e.g. apparent Km, molecular weight, and effects of divalent metals. No other naturally occurring dNTP or NTP serves as substrate, however, the enzyme may be an important site of interaction with intracellular derivatives of analogues of dUrd. It is shown here that deoxyuridine triphosphatase acts on araUTP, 6-azadUTP, 2′-FdUTP, and 2′,3′-dideoxyUTP, but the enzyme has no effect on 5-C1dUTP, 5-BrdUTP, 5-HgdUTP and dUrd-5′[α-thio]triphosphate. For the preparation of one of the analogues, the enzyme, trans-N-deoxyribosylase, from Lactobacillus, was used to prepare the deoxynucleoside from the base, a procedure that may have general usefulness.  相似文献   
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OBJECTIVE--To test the hypothesis that farmers are at high risk of hip osteoarthritis and to investigate possible causes for such a hazard. DESIGN--Cross sectional survey. SETTING--Five rural general practices. SUBJECTS--167 male farmers aged 60-76 and 83 controls from mainly sedentary jobs. All those without previous hip replacement underwent radiography of the hip. MAIN OUTCOME MEASURES--Hip replacement for osteoarthritis or radiological evidence of hip osteoarthritis. RESULTS--Prevalence of hip osteoarthritis was higher in farmers than controls and especially in those who had farmed for over 10 years (odds ratio 9.3, 95% confidence interval 1.9 to 44.5). The excess could not be attributed to any one type of farming, and heavy lifting seems the likely explanation. CONCLUSIONS--Manual handling in agriculture should be limited where possible. Consideration should be given to making hip osteoarthritis a prescribed industrial disease in farmers. There may be wider implications for the prevention of hip osteoarthritis in the general population.  相似文献   
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A synthetic diet preparation supplemented with 10% by weight of either safflower oil, hydrogenated coconut oil containing 3% safflower oil, or 'max EPA' fish oil was fed to rats over a 8-week period. Serial measurements of serum fatty acids, serum thromboxane B2 and urinary prostaglandin excretion were taken during the treatment period to assess the rate of change in fatty acid composition and prostaglandin synthesis following dietary manipulation. There was no significant change in weight gain between the dietary groups during the treatment period. Significant changes in serum fatty acids occurred within 48 h of treatment, with the 'max EPA' oil group having arachidonic acid levels reduced by 23% (P less than 0.01) compared to the coconut oil group. Conversely, rats fed safflower oil had an 18% enhancement of arachidonic acid during the same time period. Whole blood synthesis of thromboxane B2 was significantly depressed (P less than 0.01) after 48 h in rats fed 'max EPA' oil compared to the safflower oil or coconut oil groups. This suppression reached a maximum of 65% (P less than 0.001) after 7 days of dietary 'max EPA' oil treatment. The safflower oil and coconut oil-fed groups showed the same levels of serum thromboxane B2 production over the treatment period. Urinary excretion of both 6-ketoprostaglandin F1 alpha and prostaglandin E2 varied significantly (P less than 0.01) between the groups after 7 days of dietary treatment. Rats fed 'max EPA' oil had depressed urinary prostanoid excretion compared to the safflower and coconut oil groups which remained very similar to each other. After the 8-week treatment period rats were killed and the phospholipid fatty acid composition and prostaglandin-generating capacity of platelets, aorta and renal tissue was examined. Prostanoid production by kidney cortex and medulla and segments of aorta was consistently suppressed in rats fed 'max EPA' oil. These observations correlated well with changes in the phospholipid fatty acid profiles in these tissues. This study shows rapid changes in serum fatty acids and thromboxane B2 generation following dietary manipulation, while changes in urinary excretion or prostanoid metabolites occur only after a longer time period.  相似文献   
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In a retrospective survey we found that five (8·5%) out of 59 women with giant-cell arteritis had a history of thyrotoxicosis. This was significantly higher than in a control group of patients. Giant-cell arteritis and thyrotoxicosis occurred simultaneously in two cases. Knowledge of this association is of clinical use and is further evidence for an immunological basis for giant-cell arteritis.  相似文献   
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Pincus  Lauren  Croft  Marcia  Roothaert  Ralph  Dubois  Thomas 《Economic botany》2018,72(4):380-395
Economic Botany - African indigenous vegetable (AIV) production systems are often constrained by the availability of high-quality seed. Concerted efforts to improve the informal seed sector could...  相似文献   
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