Objective and fair clinical trials are the main methods for assessing the clinical significances of the experimental findings. The development of translational medicine highly relies on high-quality clinical trials as well as trial reports. Although the definition of"quality of clinical trials"and"quality of trial reports"differs from each other, they are closely related and can be consistent in most circumstance in the context of"scientific integrity". The quality of trial reports can be basically assessed by their internal and external properties. The quality of a randomized trial can be assessed by Jadad scale and Cochrane collaboration's tool for assessing risk of bias, and the quality of a non-randomized trial by risk of bias tool and Newcastle-Ottawa scale. However, since Jadad scale lacks appropriate appraisal of allocation concealment and is too simple in evaluating blind method, assessment of allocation concealment should be added. A more widely accepted approach for assessing the quality of random trials is the combination of Jadad scale and Schulz's approach to allocation concealment till recent years.For non-randomized cohort studies and case-control studies, Newcastle-Ottawa scale might be suitable at present time.

Objective To determine the content of rutin in fruits,stems,and leaves of Sambucus williamsii Hance,and provide an essential reference for the exploitation and utilization of the resources. Methods The content of rutin was analyzed on an Agilent ZORBAX Eclispse XDB C18 column(150 mmí4. 6 mm,5 μm). The mobile phase was methanol-0. 1%phosphoric acid (4555),the column temperature was set at 25 ℃,the flow rate was 0. 8 mL·min-1,and the detection wavelength was set at 360 nm. Results The linear range of rutin was 0. 105-0. 525 μg (r=0. 999 6),the average recovery was 97. 86%,and RSD was 0. 49%. The content of rutin in stems, leaves, and fruits of Sambucus williamsii Hance was 0. 171, 0. 522, and 0. 165 mg·g-1 ,respectively. Conclusion The stems,leaves and fruits of Sambucus williamsii Hance all contain rutin,but at a significant different content level. The leaves contain the highest level of rutin.

Since pig is an important livestock species worldwide, its gene expression has been investigated intensively, but rarely in brain. In order to study gene expression profiles in the pig central nervous system, we sequenced and analyzed 43,122 highquality 5′ end expressed sequence tags (ESTs) from porcine cerebellum, cortex cerebrum, and brain stem cDNA libraries, involving several different prenatal and postnatal developmental stages. The initial ESTs were assembled into 16,101 clusters and compared to protein and nucleic acid databases in GenBank. Of these sequences, 30.6% clusters matched protein databases and represented function known sequences; 75.1% had significant hits to nucleic acid databases and partial represented known function; 73.3% matched known porcine ESTs; and 21.5% had no matches to any known sequences in GenBank. We used the categories defined by the Gene Ontology to survey gene expression in the porcine brain.

OBJECTIVETo determine lignan content in the vine stem of Schisandra chinensis during 12 months and provide the scientific basis for the development and utilization of the resources.

METHODAnalysis was carried out on an Eclipse XDB C18 column eluted with a mixture of methanol-acetonitrile-water (43: 28: 29) as the mobile phase. The flowrate was 1.0 mL x min(-1), and the detection wavelength was set at 250 nm. Schisandrin, deoxyschizandrin and schisandrin B were used as reference substance, and the external standard method was used.

RESULTThe content of three constituents in the vine stem varied under different months. Schisandrin's maximum is 2.3 mg x g(-1) in December, minimum is 1.4 mg x g(-1) in April. A Deoxyschizandrin's maximum is 0.8 mg x g(-1) in November, minimum is 0.4 mg x g(-1) in March; Schisandrin B's maximum is 3.0 mg x g(-1) in January, minimum is 1.1 mg x g(-1) in April.

CONCLUSIONThe collection seasons for the vine stem of S. chinensis are autumn and winter.

Chromatography, High Pressure Liquid ; Cyclooctanes ; chemistry ; Lignans ; chemistry ; Plant Stems ; chemistry ; Polycyclic Compounds ; chemistry ; Schisandra ; chemistry

(0.05)). The sensitivity and the agreement rate were best at dose of Dob 10 ?g?kg~(-1)?min~(-1) with (86.5)% and (86.5)% (Kappa(0.71)), respectively. When Isoket combined with Dob 3,5 ?g?kg~(-1)?min~(-1), the sensitivities and the agreement rates were both significantly improved than either one used (both P

Objective:To solve international students' problems of learning difficulties and passive learning caused by language barriers in the process of biochemistry learning from the perspective of teachers in this specialty.Methods:Eighty international students were randomly divided into experimental group and control group. In the experimental group, the regional management mode was introduced in teaching, allowing students to speak mother tongues or English for group discussions on well-designed questions, and at the same time, classroom quizzes and stage tests were given, introducing formative evaluation to supervise students' learning and assess their learning performance. The control group received conventional teaching. The learning effects were assessed through a final exam and questionnaire survey. SPSS 25.0 was used to perform the Kruskal-Wallis H test and Nemenyi test. Results:Twenty-seven (75.00%) students believed that group discussion by region could deepen the discussion of questions; 27 (75.00%) no longer felt difficult, or even felt easy, to learn biochemistry; and nearly 90.00% of the students affirmed the formative evaluation mode, believing that it had positive effects on their learning attitude and behavior. In addition, the median exam score of the experimental group was 36.94% higher than that of the control class in the same year.Conclusions:Regional management combined with formative evaluation can promote international students' learning enthusiasm, improve their comprehensive achievement, and positively affect their learning behavior.

Objective:To investigate the infection rate in close contacts of COVID-19 patients before and after the last negative nucleic acid test, evaluate the effect of dynamic nucleic acid test in determining the infectivity of COVID-19 patients.Methods:Dynamic nucleic acid test results of COVID-19 cases were collected in a retrospective cohort study. COVID-19 cases with negative nucleic acid test results before their first positive nucleic acid tests were selected as study subjects. Close contacts of the index cases and the secondary close contacts were kept isolation for medical observation to assess their risk of infection.Results:This study included 89 confirmed cases from two local COVID-19 epidemics in Ningbo. A total of 5 609 close contacts were surveyed, the overall infection rate was 0.20%. No close contacts of the COVID-19 cases before the last negative nucleic acid test were infected, and the infection rate in the close contacts of the COVID-19 cases after the last negative nucleic acid test was 1.33%, all of these close contacts lived together with the index cases. No secondary close contacts were infected.Conclusion:COVID-19 patient becomes infectious after the last nucleic acid is negative, and has no infectivity before the last nucleic acid negative.