Objective To investigate the protective effect of methotrexate on probable rheumatoid arthritis (RA) patients. Methods 62 probable rheumatoid arthritis (RA) patients were randomly divided into two groups, treatment group (32 cases) accepted methotrexate and non-steroidal anti-inflammatory drug and control group only non-steroidal anti-inflammatory drug. In the 2-year follow-up visit, patients who developed to RA would withdraw and accept normal combined medicine treatment. They were assessed with X-ray changes of the hand joints. Results 8 cases of the treatment group developed RA (2 cases withdrew because of intolerance), while 17 cases of the control group developed RA. The treatment group developed RA later than the control group, with less radiographic joints injury in 2 years. Conclusion Methotrexate can delay clinical process of the development of RA in the probable RA patients and reduce joints damage.

Objective To investigate the genetic diversity of five populations of cultivated Morinda officinalis in Guangdong Province using random amplified polymorphic DNA(RAPD).Methods Sixty-four individuals in five populations of cultivated M.officinalis were analyzed by RAPD markers to determine the genetic variations among the populations.The data of genetic diversity were analyzed with Popgen32 software.Results The levels of genetic variation and patterns of population structure in M.officinalis were investigated using RAPD markers.Of the 100 primers screened,15 primers produced highly reproducible RAPD bands,using these primers,224 discernible DNA fragments were generated with 112(50.00%) polymorphic fragments,indicating considerable genetic variation at the species level.In contrast,there were relatively high levels of polymorphism at the population level with the percentage of polymorphic bands ranging from 37.05% to 53.13%,and the mean percentage of polymorphic loic(P=45.86%).Genetic variation among populations was detected based on Nei's genetic diversity analysis(0.175 6),Shannon's diversity index(0.287 6) for every population with Shannon's index 0.103 3—0.236 2 and Nei's indexes 0.074 5—0.154 0.Conclusion There is a little genetic differentiation among populations of cultivated M.officinalis and result in different cultivated types,the genetic diversity with M.officinalis(POP2) is higher than that of other populations.It may be the main reason of the difference of cultivated M.officinalis quality.