Pandemic influenza A (H1N1) virus infection factors among healthcare workers - a case-control study / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore factors related to pandemic influenza A (H1N1) virus infection among healthcare workers.</p><p><b>METHODS</b>H1N1 influenza confirmed cases of health workers in hospital of Beijing from Aug 30th 2009 to Jan 31st 2010 were included. A 1:4 matched case-control study was conducted with 54 healthcare workers who were infected by influenza A(H1N1) virus and 216 matched controls who were not infected. Face-to-face interview with questionnaires was used to collect information of work and family aspects of the study participants. Conditional logistic regression was used to analyze the H1N1 infection factors.</p><p><b>RESULTS</b>The age was 29.6 ± 7.4 years old and male subjects accounted for 17.4% (47/270). There were 5.6% (3/54) and 34.4% (74/216) of the cases get the influenza A (H1N1) vaccine immunization separately in the case group and control group. Among 18.5% (10/54) and 40.1% (88/216) of the cases and controls used high protection level masks during the epidemic. Besides, 33 (61.1%)and 161 (74.5%) cases lengthening the time of mask wearing separately. There were 13 (24.1%) and 85 (39.4%) cases using disposable tissue to clean hands in the case group and control group, 24 (44.4%) and 46 (21.3%) cases feel they were much easier to get infected in respiratory disease than others based on experience in the case and control group. Univariate analysis showed that factors such as using disposable tissue to clean hands (OR = 0.15, 95%CI = 0.04 - 0.57), lengthening the time of mask wearing (OR = 0.43, 95%CI = 0.20 - 0.92), using high protection level masks (OR = 0.26, 95%CI = 0.11 - 0.58), getting influenza A (H1N1) vaccine immunization (OR = 0.04, 95%CI = 0.01 - 0.32), much easier to get infected in respiratory disease than others based on experience (OR = 2.85, 95%CI = 1.44 - 5.62), were all associated with influenza A (H1N1) infection. Results of multivariate logistic regression analysis showed that variables such as history of influenza A (H1N1) virus immunization (OR = 0.18, 95%CI = 0.06 - 0.51), using high protection level masks (OR = 0.05, 95%CI = 0.01 - 0.35), much easier to get infected in respiratory disease than others based on experience (OR = 3.69, 95%CI = 1.58 - 8.63) were all correlated to influenza A (H1N1) infection.</p><p><b>CONCLUSIONS</b>Factors such as history of influenza A (H1N1) vaccine immunization, using high protection level masks and improving respiratory health can protect healthcare workers from infection of influenza A (H1N1).</p>

Estimation on the real number of novel influenza A (H1N1) cases, Beijing, 2009 / 中华流行病学杂志

Objective To estimate the real number of novel influenza A(H1N1 ) infection in Beijing, 2009. Methods A multiplier model (Impact 2009 v 1.0 software) based on Monte Carlo approach was used to estimate the real number of novel influenza A (H1N1 ) based on the number of influenza-like illness (ILI) cases, novel influenza A(H1N1 ) positive rate among ILI cases and rate on clinical visit of ILIs in secondary and tertiary hospitals. Results There were 1.80 million (90%CI: 1.46-2.30) estimated novel influenza A (H1N1) cases in 2009 in Beijing with the rate of infection as 11.0%. One reported case would represent 167 real infections. The highest age groups of infection were 0-4 years and 5-14 years, being 32.5% and 33.3%, respectively. Conclusion Laboratory-confirmed infections with novel influenza A (H1N1 ) only represented a fraction of the total cases in a population, suggesting that it was imperative to estimate the real number of novel influenza A (H1N1) infection.

The growth of Salvia miltiorrhiza seedling and root system following transplantation / 中国中药杂志

<p><b>OBJECTIVE</b>To study the relationship between plant growth and accumulation of active ingredients in Salvia miltiorrhiza.</p><p><b>METHOD</b>Transplants of S. miltiorrhiza were sampled at 20 day intervals. At each stage, the growth of seedling and root system was recorded and the contents of tanshinone II (A) and salvia acid were measured.</p><p><b>RESULT AND CONCLUSION</b>This study showed that the rapid growth stage of the root system lags behind that of the seedling system, but the growing period of root system lasts longer. The quantitative change of roots reveals a double "S" curve; two rapid growth stages emerge during 30 - 70 days and 140 - 200 days after the seedlings were transplanted. The content of salvia acid reaches the highest level during 140 - 180 days, whereas the content of tanshinone peaks during 100 - 120 days.</p>

Study on configuration fabric and germinative conditions of Salvia miltiorrhizy seeds / 中国中药杂志

<p><b>OBJECTIVE</b>To provide theoretic warrant and technical reference for Salvia miltiorrhizr standardization planting, by carrying out various systemic studies such as observation of seeds configuration fabric, idiosyncrasy of water absorption and groping germinating conditions.</p><p><b>METHOD</b>In the study of configuration fabric, seeds were observed and taken photos by scanning electronic microscope, and heft method was used for measuring changes of water absorption velocity and dehydration velocity. Seeds germination conditions were probed into under the national test regulations for crop seeds and related prescription from international standards.</p><p><b>RESULT</b>(1) There was a layer of slime about 10-20 microm thickness covering epicarp of Danshen seeds. The slime formed as diamond meshwork (reseau) and the weight of it was 8%-10% of total seeds weight. (2) The speed of water absorption of seeds was extremely rapid. The weight of seeds could increase above 10 times as original while the dehydration velocity was quite low. (3) The optimal temperature for the seeds germination is around 25 degrees C, and the germination rate of the new seeds gained yearly was above 75%, but the rate would decrease sharply as years went by. It was also found that the seeds germination power and exponent of vigor were quite high under the temperature transformation between 23 degrees C, 28 degrees C. Such treatments as pre-cool, PEG treatment and infusing with GA3 could increase the rate of seeds germination capacity obviously.</p>