Aptamers are short single-stranded nucleic acid ligands that are capable of binding almost any targets with low nano- to picomolar affinities and exceptional specificities. They are selected out of a large combinatorial oligonucleotide library through an in vitro evolution process termed SELEX (systematic evolution of ligands by exponential enrichment). The unique advantages of high-throughput screening technique and aptamers in precise recognition as well as easiness to synthesis and modification bring aptamers a bright prospect in analytical chemistry, biology and medicine research. The recent advances in the SELEX technique and aptamers are reviewed.

砄bjective: To assess interexaminer errors in traditional cephalometric analysis so as to improve the accuracy . Methods : Ten cephalometric radiographs were selected randomly and 12 angular and 5 liner parameters were measured by 5 orthodontists in one week according to the original landmarks. The results were quantified with that of computer based. Results: The mean errors of some measurements were larger than 0.5, such as SL,GoGn SN, SE,FMA,FMIA,OP SN, 1 1 ,IMPA and SNA,while only those of SL and GoGn SN were larger than 1.0. Conclusion: Statistical significant differences are found in the The errors of measurements which need assisted line among the examiners but not found in the errors between angle measurements and liner measurements?

OBJECTIVE:To observe the clinical short-term efficacy and safety of brucea javanica oil injection combined with oxaliplatin and xeloda in the treatment of elderly patients with advanced gastric cancer. METHODS:82 elderly patients with ad-vanced gastric cancer were randomly divided into control group and observation group. Control group was treated with Oxaliplatin injection 130 mg/m2 added into 5% Glucose injection 250 ml for 2 h,iv,d1+Xeloda tablets 1 000 mg/m2,orally,twice a day, d1-14;based on the treatment of control group,observation group was additionally treated with 10% Brucea javanica oil injection 30 ml added into 0.9% Sodium chloride injection 250 ml,iv,once a day,d1-14. 21 days were as a treatment course,and it lasted 3 courses. The short-term efficacy,life quality and toxicity reactions were evaluated in 2 groups. RESULTS:The short-term efficacy in observation group was significantly higher than control group,life quality was significantly better than control group,and the in-cidences of leucopenia and liver damage were significantly lower than control group(P<0.05). CONCLUSIONS:Brucea javanica oil injection combined with oxaliplatin and xeloda has better efficacy than oxaliplatin combined with xeloda in the treatment of elder-ly patients with advanced gastric cancer,with good safety.

Objective To explore the CT and MR imaging findings of acinic cell carcinoma (ACC)in salivary gland and enhance the diagnosis of this rare disease.Methods The CT and MR imaging characteristics of 20 patients (7 males and 13 females,median age 44 years old) with pathologically proved ACC were retrospectively reviewed.CT and MR images were evaluated in relation to the following: location,size,morphology,margin,CT density/MR signal intensity and enhancement pattern.Results Twelve lesions were located in parotid gland,two lesions in maxillary Sinus,and one lesion in submandibular,parapharyngeal,infratemporal fossa,buccal,nasal cavity,and hard palate respectively.The size of lesions were 0.7～5.8 cm.Sixteen lesions less than 3 cm in size demonstrated round or oval round masses with well defined margin.Four lesions more than 3 cm in size demonstrated irregular masses with unclear margin.Among them,bony destruction of the wall of the maxillary sinus was noted in 3 cases,and the preauricular skin was invaded in 1 case.The densities (signal intensity) were homogeneous in 6 cases and heterogeneous in 14 cases.Lesions were slightly low density in 11 case and isodensity in 3 cases on CT plain scan.Lesions were homogeneous isointense in 2 cases and heterogeneous isointense in 4 cases on T1WI,heterogeneous hyperintense in all cases on T2WI.On post contrast images,lesions demonstrated remarkable enhancement in 14 cases,moderate enhancement in 2 cases and mild enhancement in 3 cases.Conclusions The imaging characteristic of ACC were nonspecific.CT and MR could accurately detect the extent of tumor involvement and was helpful to provide more comprehensive information for the strategy of clinic therapy.

Objective:To investigation the veracity of orientation on modified upright lateral cephalometric radiographs. Methods:Fifty upright lateral cephalometric radiographs were analysed randomly.Twenty-three subjects,who had standard radiographs, were taken with modified technique. The chracterics both of radiographs were compared. Results:The orientations of porion?FH plane and the superimpositions of left and right gonion point on modified standard radiographs were more veracity. Conclusion:The veracity of orientation on upright lateral cephalometric radiographs can be improved.

Objective To evaluate the efficacy of percutaneous CT guided interstitial 125Ⅰ seeds implantation treatment for refractory pelvic malignant tumors and discuss the procedure of technique.Methods Twenty-three patients with refractory pelvic malignant tumors(25 lesions,diameter 3.5-7.0 cm,mean 4.5 cm) showing failure response to full chemotherapy and/or radical radiotherapy after tumors resection were undergone percutaneous CT guided intratumoral 125Ⅰseed implantation.Treatment plan system(TPS)was used to design the distribution and number of 125Ⅰ seeds according to matched peripheral dose(MPD)1-3 days before the procedure.Of which 6 cases received combined internal iliac arterial infusion chemotherapy before or after the 125Ⅰ seed implantation procedure.Results 9 ～ 75(mean 27)125Ⅰ seeds were implanted into a single tumor at first time including 6 patients with intraarterial chemotherapy for 14 cycles(mean 2.3 cycles),showed relief of clinical pain symptoms in 16 of 23 cases,72 h ～ 4 w after the seeds implantation;with the an effective rate of 69.6%.Follow up for 2-34 months(median,21 months),CT or MRI performed 2 months after the seeds implantation showed no CR,but PR in 18 cases,SD in 4 cases,and PD in 1 case,with overall response rate of 78%(18/23),and no serious complication.In addition,20 cases survived,with the longest one of 34 months and the other 3 died.Conclusions Intratumoral 125Ⅰ seeds implantation under CT guidance for pelvic refractory malignant tumors is safe,minimally invasive,and effective.

ObjectiveTo explore the characteristic CT features of benign and malignant submandibular gland lesions.Methods CT scans of 75 cases of submandibular gland lesions verified pathologically after surgery were analyzed retrospectively,including 38 cases of pleomorphic adenoma,22 cases of malignant tumors,11 cases of chronic submaxillaritis,2 cases of myoepithelioma,1 case of neurilemoma and 1 case of hemangioma.Results ( 1 ) All 38 cases of submandibular gland pleomorphic adenoma only occupied a part of submandibnlar gland.Thirty five lesions were on the edge of submandibular gland.The edge of 33 lesions were smooth and the density of 30 lesions were even.Thirty three lesions were slightly or moderately enhanced and 10 lesions showed “target sign” on enhanced CT.( 2 ) There were 22 cases of submandibular gland malignant tumors.Three lesions of lymphoma located at the edge of submandibular gland with smooth edge and even density,and showed mild to moderate enhancement.The remaining 19 lesions showed rough edge and uneven density.Eighteen of the 19 lesions showed ill-defined boundary,2 of the 18 lesions invaded most of submandibular gland and 16 of the 18 lesions invaded the whole submandibular gland.Seventeen lesions were unevenly enhanced,thickened,cirvilinear vessels were seen in 12 of the 17 lesions.Nine cases were accompanied with swollen lymph nodes ( minor diameter greater than 1.0 cm) in neck.(3)There were 11 cases of chronic submaxillaritis,which showed enlargement of the whole submandibular gland with relative smooth edge and relative clear boundary.Most of lesions were moderately and evenly enhanced.Six cases were companied with submandibular duct lithiasis and dilatation.All of 11 cases were accompanied with lymph node enlargement in neck.(4) Two cases of myoepithelioma demonstrated irregular ring enhancement on CT;one case of neurilemoma showed obvious cystic changes and slight enhancement on the edge;1 case of hemangioma showed multiple phleboliths and prolonged contrast enhancement.ConclusionsMost of submandibular gland benign and malignant lesions show some degree of characteristic CT findings.It is relatively difficult to discriminate between lymphoma and submandibular gland pleomorphic adenoma.

BACKGROUND:The aquaporin (AQP), mainly AQP1, AQP4 and AQP9, are expressed in mammalian brain, while the others are sporadical y expressed. There is no evidence concerning the distribution, function and regulation mechanism of AQP in the brain.
OBJECTIVE:To comprehensively analyze the research progress of the distribution, function and regulation mechanism of AQP in maintaining normal physiological function of the brain.
METHODS:An online retrieval of PubMed database and CNKI database between January 1980 and July 2013 was performed for articles on the distribution, function and regulation mechanism of AQP, with the key words of“AQP1, AQP4, AQP9, function, brain, adjusting mechanism”in English and Chinese. A total of 163 papers were screened out and 85 of them met the inclusive criteria.
RESULTS AND CONCLUSION:The existing studies about the expression, function and regulating mechanism of AQP1, AQP4 and AQP9 in the brain can be summarized as the fol owing three aspects: (1) AQP1 is expressed in the choroid plexus and participates in forming cerebrospinal fluid;in other types of cells, gas micromolecules CO 2 , NO, NH 3 and O 2 also cross through AQP1. (2) AQP4 is mainly expressed in the astrocytes, ependymal foot process and gelatin membranes, which can help the water in and out of the brain tissue, accelerate glial cellmigration and change neural activity. (3) AQP9 is mainly distributed in astrocytes and catecholamine neurons, the main function is involved in energy metabolism in the brain. Therefore, AQP is the key for water transport in the brain. Understanding the distribution, function and regulation mechanism of AQP wil play an important role in the treatment of brain diseases. The regulatory mechanism on the expression of AQPs in normal pathology and related disease remains unclear and related molecular signal pathway needs further exploration.

Objective To study the value and clinical significance of diffusion tensor imaging(DTI)in differentiating high-grade astrocytomas and solitary metastatic tumors of brain.Methods 16 patients with intracranial solitary metastasis and 25 patients with high-grade astrocytoma confirmed pathologically were examined with MR DTI.Mean diffusivity(MD)and fractional anisotropy(FA)were measured in the regions of interest(ROI)of peritumor and cerebral parenchyma of the normal side on DTL Fiber tractography was reconstructed and the encountered patterns of tumor-related alteration to cerebral white matter were observed.Results The peritumor were all depicted as hyperintense or isointense signals on DTI.The FA values were 0.227±0.05 and 0.169±0.07 in the peritumor of high-grade astrocytoma and metastasis respectively,which was of significant difference(P＜0.05).Furthermore,fiber tractography could display the course of white matter tracts in three-dimensional space.Conclusion DTI may be help to differential diagnosis of solitary metastasis and high-grade astrocytoma in clinical practice.

Objective To investigate the bone marrow morphology characteristics in patients with severe fever with thrombocytopenia syndrome (SFTS)and to evaluate the clinical value of bone marrow morphology examination in the diagnosis of SFTS.Methods The bone marrow morphology and clinical data of six newly diagnosed SFTS patients with positive test of novel bunyavirus infection admitted to Taizhou Hospital from July 2011 to November 2014 were retrospectively analyzed.Results The increased ratio of lymphoid and monocytoid histiocytes (0.02 - 0.23 )and hemophagocytic phenomenon were observed in all of the six patients′ bone marrow smears.Two of the six cases were diagnosed with hemophagocytic lymphohistiocytosis (HLH)according to the clinical diagnosis criteria and the remaining four cases were defined as highly suspected HLH.Conclusions The progression of SFTS disease might be closely related with HLH induced by novel bunyavirus infection.Morphology examination of bone marrow smear is beneficial for the early differential diagnosis of SFTS.