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71.
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
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The objective was to study prospectively the relation between quantity and type of alcohol and risk of gastric cancer. In a pooled database from three population studies conducted in 1964-1992, a total of 15,236 men and 13,227 women were followed for a total of 389,051 person-years. During follow-up 122 incident cases of gastric cancer were identified. Total alcohol intake itself was not associated with gastric cancer, but type of alcohol seemed to influence risk. Compared with non-wine drinkers, participants who drank 1-6 glasses of wine had a relative risk ratio of 0.76 (95% confidence interval (CI) 0.50-1.16), whereas those who drank >13 glasses of wine per week had a relative risk ratio of 0.16 (95% CI 0.02-1.18). Linear trend test showed a significant association with a relative risk ratio of 0.60 (95% CI 0.39-0.93) per glass of wine drunk per day. These relations persisted after adjustment for age, gender, educational level, body mass index, smoking habits, inhalation and physical activity. There was no association between beer or spirits drinking and gastric cancer. In conclusion, the present study suggests that a daily intake of wine may prevent development of gastric cancer.  相似文献   
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A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM.  相似文献   
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ObjectivesTo develop an international consensus on managing penile cancer patients during the COVID-19 acute waves. A major concern for patients with penile cancer during the coronavirus disease 2019 (COVID-19) pandemic is how the enforced safety measures will affect their disease management. Delays in diagnosis and treatment initiation may have an impact on the extent of the primary lesion as well as the cancer-specific survival because of the development and progression of inguinal lymph node metastases.Materials and methodsA review of the COVID-19 literature was conducted in conjunction with analysis of current international guidelines on the management of penile cancer. Results were presented to an international panel of experts on penile cancer and infection control by a virtual accelerated Delphi process using 4 survey rounds. Consensus opinion was defined as an agreement of ≥80%, which was used to reconfigure management pathways for penile cancer.ResultsLimited evidence is available for delaying penile cancer management. The consensus rate of agreement was 100% that penile cancer pathways should be reconfigured, and measures should be developed to prevent perioperative nosocomial transmission of COVID-19. The panel also reached a consensus on several statements aimed at reconfiguring the management of penile cancer patients during the COVID-19 pandemic.ConclusionsThe international consensus panel proposed a framework for the diagnostic and invasive therapeutic procedures for penile cancer within a low-risk environment for COVID-19.  相似文献   
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To examine serum YKL‐40 in women developing gestational diabetes mellitus (GDM). In the present large observational cohort study of 1179 pregnant women, we determined serum YKL‐40 four times during pregnancy (at gestational age 12, 20, 25, and 32 weeks). Pregnancy outcome was obtained from medical records. Sixty‐eight women (5.8%) developed GDM. Serum YKL‐40 increased from gestational age (GA) 12 weeks and the following weeks in the women who developed GDM and was independent of BMI, parity, and maternal age (OR = 2.69, 95% CI: 1.45–5.00, p = 0.002). No association was found between serum YKL‐40 and the oral glucose tolerance test results. In conclusion, YKL‐40 significantly increased in pregnant women with GDM compared with women without GDM, probably reflecting the low‐grade inflammation of GDM. However, we did not find an association between serum concentrations of YKL‐40 in early pregnancy and the development of GDM and thus we conclude that YKL‐40 alone is not usable as a biomarker for early prediction of GDM.  相似文献   
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