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.

Objective To investigate the feasibility of hand-assisted laparoscopic liver resection without hand-port devices. Methods Eight patients were selected into the study, including 5 cases of primary liver cancer located at the segment Ⅳ or Ⅴ or the left lateral lobe, 2 cases of liver spongy hemangioma and 1 case of hepatic focal nodular hyperplasia. After the laparoscopic devices were set up, an oblique incision below the right costal margin was made. The length of the incision was the same as the operator’s wrist. In the absence of hand-port or “blue disc”, the operator’s left hand directly entered the abdominal cavity through the incision. With the assistance of operator’s left hand, the laparoscopic liver resection was conducted, with the ligaments surrounding the liver dissociated, the liver transected and the cut surface properly managed. Results Laparoscopic liver resection was performed successfully in all the 8 patients. The operation time ranged 90～180 min (mean, 118 min), and the blood loss was 50～ 300 ml (mean, 160 ml). There was no uncontrolled bleeding during the operation and no complication happened. Conclusions Hand-assisted laparoscopic liver resection without hand-port devices is a safe and feasible procedure. It may not only reach the purpose of hand assistance but also lower the surgical costs.

Cell culture and SDS-polyacrylamide gel electrophoresis (PAGE) methods were employed to analyse the role of human amniotic basement membrane (HABM) in supporting the growth of forebrain neurons and the components of HABM after enzymatic digestion. It was found that HABM treated with heparinase Ⅱ supported the growth of forebrain neurons 150% of that of the untreated HABM control. The results of SDS-PAGE analysis showed that HABM treated with heparinase Ⅱ had collagen-like polypeptides 2?_1 (260kD) and 2?_2 (225kD) reduced and lamininlike peptides (212kD and 200kD) increased; and that HABM treated with heparinase I or collagenase I had laminin reduced. This indicated that laminin is the major component in HABM to promote the growth of forebrain neurons.

Objective:To investigate the alveolar bone defects of anterior alveolar bone in patients with bimaxillary protrusion by using cone-beam computed tomography ( CBCT ) . Methods: The samples consisted of 50 patients with bimaxillary protrusion, who were assigned to the teenage group[20 cases, (13. 1 ± 1. 0) years] and adult group[30 cases, (22. 9 ± 4. 2) years] . The adult group included 9 hy-po-divergent, 11 normo-divergent and 10 hyper-divergent patients. The images were obtained by using NewTom VG CBCT and the alveolar defects were evaluated. Results:The ratio of the patients had alveo-lar bone defects was 94. 00%. Meanwhile, the defects were associated with 38. 60% of all the teeth. Most defects occurred on labial alveolar bone ( 98 . 66%); fenestration was found more in the maxillary alveolar region and dehiscence occurred more in the mandible. The dehiscences (3. 06%) and defects prevalence (30. 13%) of the teenage group were significant lower than those of the adult group (11. 73% vs. 42. 46%), P<0. 05; while there was no significance of the fenestrations prevalence between the two group (P>0. 05). The hypo-divergent group had lower fenestrations prevalence (22. 22%) than the normo-divergent (33. 84%) and hyper-divergent groups (37. 50%), P<0. 05. The upper central incisor had the lowest alveolar bone defect prevalence. Conclusion: Alveolar bone defects are common findings in patients with bimaxillary protrusion before orthodontic treatment. The prevalence of defects is affected by age and vertical-growth type.

Objective:To analyze the effect of Bone morphogenesis 4 and its antagonist Noggin on morphogenesis of tongue.Methods: Dissected rats to get embryonic day 13(E13) tongues;fed E13 tongues in standard medium,BMP4(0.03 mg/L,0.3 mg/L,1 mg/L),and the antgonist Noggin(1 mg/L,3 mg/L,10 mg/L) medium;cultured for 3 days;fixed samples,observed tongues with scanning electronic microscope(SEM);measured the whole tongue length,anterior 1/8,1/4 width and middle width of cultured tongues and analyzed data with SPSS 10.0.To further study the effects of BMP4 on epithelial and mesenchymal cell proliferation,Affi-gel blue gel beads were applied.Beads were soaked in PBS and BMP4(667 mg/L),and implanted in the E13 embryonic tongues;then after cultured in standard medium for 3 days,tongues were embedded in O.C.T.and cut into 12 ?m series sections.Ki67 was detected by immunohistochemical method.Results:(1)Whole length of tongues changed greatly(P

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).

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.