OBJECTIVE:To establish a method for content determination of dihydroartemisinin in Dihydroartemisinin and piper-aquine phosphate tablets. METHODS:HPLC was performed on the column of Waters YMC-Pack ODS-AQ with mobile phase of acetonitrile-water(gradient elution)at the flow rate of 1.0 ml/min,the detection wavelength was 216 nm,column temperature was 30℃,and injection volume was 20 μl. RESULTS:The linear range of dihydroartemisinin was 0.009 650-1.930 mg/ml(r=0.999 9);RSDs of precision,stability and reproducibility tests were no more than 0.5%;average recovery was 100.76%(RSD=0.95%,n=9). CONCLUSIONS:The method is simple,rapid and accurate,and can be used for the content determination of dihydroartemis-inin in Dihydroartemisinin and piperaquine phosphate tablets.

The late-preterm infant refers to the infant who is born at 340/7 through 366/7 week's gestation.In recent years,the number of the late-preterm continually ascends and the proportion of them in the preterm group increase as well.Recent studies find that the rates of morbidity and mortality of late-preterm infants are much higher than those of term infants.The rise of the proportion of the former and the more medical resources consumed attract the considerable attention thereby.In this article,we will review late-preterm infants' morbidity of several systems and its influential factors in order to provide more information for perinatal medical staff to improve diagnosis,treatment and further research.

The formation and progression of tumor is inseparable from the changes of cell cycle regulatory proteins.The G2-M period block effect of tumor cells is especially important in slowing the growth of tumor and improving the curative effect.DNA damage receptor,signal transduction factor and effectors are the classical pathways to mediate G2 phase arrest of tumor cells,and have the potential to be new targets for tumor therapy.

While only in minute quantities in the body, trace elements are crucial co-factors and regulators of normal metabolism.Commonly tested elements include calcium, magnesium, iron, zinc, and copper.Imbalance or deficiencies in trace elements can cause growth retardation, malnutrition, immune malfunction and other abnormalities in children.Because these elements are in trace amounts, sensitivity and reproducibility of detection methods are of paramount importance.Different methods for the same element can yield different reference intervals, which, in order to be applied in the clinic, would have to be independently established by individual laboratories.Clearly defined indications and good quality control to ensure accuracy and sensitivity are necessary for the measurement of trace elements to provide objective reference for clinical diagnosis.

Objective:To investigate the protective effects of matrine(MT) preconditioning against hepatic ischemia-reperfusion injury in rats. Methods:Fifty male SD rats were randomly allocated into 5 groups:sham operation(SO) group,ischemia-reperfusion (NS) group and MT preconditioning groups (of 3.75,7.5,15 mg/kg). Rats of NS and MT groups were injected normal saline or MT,respectively; and 15 min later,the pedicales of the left and median liver lobes were clampped for 45 minutes,and reperfused for 40 min. The portal trial were only separated but not obstructed in SO rats. After reperfusion,the serum activity of ALT,AST and LDH was determined,the activity of SOD and content of MDA in liver tissue were examined,and histopathological changes of liver were observed. Results:Compared with those of NS group,the serum levels of ALT,AST,LDH,and the content of MDA in liver tissue of MT groups were lower,and the activity of SOD was higher(P

The serum concentration of vitamin A (VA) and B-carotene were determined in 50 healthy pregnant women in the later trimesters and parturition, their newborns and 20 non-pregnant women. In the meantime the contents of placental tissues were determined too. The results showed; 1. The serum VA content(2.17 umol/L, 62ug/dl)of pregnant women in the later trimesters was higher than that of non-pregnant women (1.37umol/L, 39ug/dl), but it decreased immediately after delivery. 2. There was no significant def-ference of the serum B-carotene concentration between the pregnant women and non-pregnant women. 3. The cord blood VA and B-carotene contents were much lower than those of maternal blood. 4. The contents of B-caro-tene in placentas were 9.6 times as much as VA. 5. The efficiency of transport of B-carotene from maternal blood to placental tissue was higher than that of VA, and lower than that from placenta to cord blood.

DNA methylation is one of the regulators on the expression of genes,and the expression of genes can be ”silenced” by hypermethylation of the tumor suppressor genes,which is in close relationship with carcinogenesis.Gastric cancer is caused by multiple factors and multiple genes alteration and prolonged interaction.among them ,There is considerable relation between the hypermethylation of the tumor suppressor genes and the gastric carcinogenesis.

OBJECTIVE:To study the restraining factors in the intravenous immune globulin(IVIG.)bacterial endotoxin test.METHODS:A series tests were designed;the sensitivity of limulus was checked and the limit of endotoxin was validated;the effects of vehicle and pH value on the IVIG endotoxin test results were observed so as to find out the chief restraining factors of this test method.RESULTS:Lower pH value has an inhibition effect on the in IVIG bacterial endotoxin test.CONCLUSION:Bacterial endotoxin test can replace the rabbit testing method in the pyrogen test of IVIG.When the condition of lower pH is changed.

AIM: To study the effect of estrogen on injury induced by ?-amyloid protein (A?) in primary cultures of rat cortical neurons. METHODS: The effect of 17?-E_2 on A?(25-35)-induced cell death in primary rat cortical neurons was observed by phase contrast light microscopy, Giemsa staining and determination of lactate dehydrohenase (LDH) release rate. RESULTS: A?(25-35) induced cell death in rat primary cortical neurons. Forty eight hours pretreatment with 17?-E_2 protected rat primary cortical neurons from A?(25-35)-induced injury. CONCLUSION: A? evokes toxicity in rat primary cortical neurons. Estrogen can protect the rat primary cortical neurons against injury induced by A? (25-35).

Objective:To find a better way to protect the security and interests of vulnerable groups by exploring the problem of protecting the vulnerable groups in drug clinical trial from the perspectives of ethics committees,organization and researchers.Methods:According to the relevant literature and the actual situation of the hospital,this paper analyzed the security issues of vulnerable groups comprehensively.Results:Only the ethics committees,organization and researchers work together,can it protect the security and interests of vulnerable groups to the greatest extents.Conclusion:Further research on the security of vulnerable groups not only promotes the development of human health,but also plays a decisive role in improving the protection of subjects in drug clinical trial.