On the basis of principal-agent theory,this paper analyzed the reasons of doctor-patient problems from the perspective of patients and hospitals,hospitals and physicians,and patients and physicians.It included asymmetric medical information,ethical risks of physicians,incomplete contracts between physicians and patients,and uncertainty of medical results.Aimed at these problems,this paper put forward relevant suggestions.In the view of recognition,patients are supposed to get a rational idea in the process of selecting hospitals and try making a contract with general practitioners.In the view of improvement,the pattern of performance assessment to physicians should be developed.In the view of system,the corresponding management measures of health service should be improved so as to better serve patients.

OBJECTIVEWe aim to evaluate the cytotoxicity and antibacterial effects of Silagum-Comfort (SLC) silicone-based soft liner varnish containing Ag/TiO2 in vitro.

METHODSSilicone-based liner circular specimens, with a diameter of 10 mm and a thickness of 2 mm, were created and divided into six groups randomly. Ag/TiO2 was incorporated into the SLC varnish based on the agent/material weight rate of 0, 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%. The mixed varnish was used to polish the SLC specimens. Antibacterial specimens (ATSLC) were created. Methyl thiazolyl diphenyl-tetrazolium bromide assay method was used to evaluate the 3T3 cell cytotoxicity of ATSLC in vitro. Surface roughness (Ra) measurements of ATSLC were obtained. The antibacterial effect of ATSLC on Candida albicans was examined using the pelliclesticking method.

RESULTSThe cytotoxicity of ATSLC was graded from 0 to 2. The Ra of ATSLC increased when Ag/TiO2 agent concentration increased. However, the differences were not statistically significant compared with the 0 group. With increasing Ag/TiO2 concentration, the antibacterial agent concentration and the antibacterial rate of ATSLC also increased. When the Ag/TiO2 antibacterial agent concentration reached 2.0% and 2.5%, the antibacterial rate increased to 97.5% and 96.5, respectively.

CONCLUSIONVarnish containing Ag/TiO2 has excellent antibacterial effect and can significantly improve the antibacterial effect of silicone-based soft liner.

AIM: To investigate the inhibitory effects of genistein(Gen) on mouse allergic contact dermatitis(ACD).METHODS: The animal model of ACD was induced by DNFB.The effects of different doses of Gen on mouse ear swelling,body weight,histopathological changes in mouse ear skin,thymus index and spleen index were observed.RESULTS: All groups of Gen inhibited mouse ear swelling induced by DNFB significantly.The infiltration of inflammatory cells and thymus index were also reduced.However,the increase in mouse body weight was not affected.Low dose of Gen increased spleen index,high dose of Gen decreased spleen index.CONCLUSION: Genistein has significant inhibitory effects on mouse ACD induced by DNFB.

Objective To explore the effect of hemeoxygenease/carbon monoxide system on hypoxic pulumonary vascular structural remodeling. Methods Twenty six Wister rats were randomly divided into four groups:control groups( n =6),hypoxia group( n =7),hypxia+ZnPP group( n =6) and hypoxia+CO group( n =7).Pulmonary artery mean pressure(mPAP) of each rat was elaluated by using right cardiac catheterization,the ultrastructaral changes in intra acinar pulmonary muscularized arteries were observed. Results mPAP was significantly increased in hypoxic rats(22?2 31?mmHg)as compared with that of normal controls(16 57?2 51mmHg)( P

AIM: To study the suppressive effect of glycyrrhizin (GL), a Chinese medicine, on DNFB-induced contact hypersensitivity in mice. METHODS: BALB/c mice were divided into 5 groups according to different medication: GL 1 (11 mg/kg) group; GL 2 (22 mg/kg) group; GL 3 (44 mg/kg) group; dexamethasone (DXM, 0.75 mg/kg) group; and normal saline group. For induction of contact hypersensitivity (CHS) to DNFB, mice were sensitized to abdomen and challenged to right ear by epicutaneously DNFB. Each mouse was administrated intraperitoneally on day 1 to day 5 with different medication. The suppression of mice CHS by different medication were evaluated 24 hours after elicited, according to ear thickness difference, ear weight difference and pathological change of challenged ear section. Thymus index and spleen index were calculated to see the effect on mouse immune system to CHS. RESULTS: Compared with normal saline group, the ear thickness difference and ear weight difference were both significantly reduced in GL1, GL2, GL3 and DXM groups (P

AIM:To analyze the effects of oxymatrine(OMT) on the quantity of murine regulatory T cells(Tr cells) in the peripheral blood and mouse lymphocyte proliferation stimulated by Con A,and to probe into the immunological mechanism that OMT treats allergic contact dermatitis(ACD).METHODS:An ACD mouse model stimulated by dinitrofluorobenzene(DNFB) was established.Different dosages of OMT,PBS and hydrocortisone(HCT) were intraperitoneally injected(IP) into the mice.Blood samples were collected at 1 d,7 d,14 d,21 d and 28 d,then the T cells were isolated and marked with anti-CD3,anti-CD4,anti-CD25 three-colored immune fluorescence antibody to detect the quantity of CD4+CD25+ T cells with flow cytometry.The fluorescence intensity changes of lymphocytes which were isolated from mouse's lymph node and co-stimulated by polyclonal stimulator Con A and OMT were examined by carboxyfluorescein diacetate succinimidyl ester(CFDA-SE) staining and flow cytometry.RESULTS:OMT at concentrations of 500,125 and 31 mg/L had the ability to restrain the proliferation of lymphocytes from lymph node in a dose dependent manner.However,OMT at concentrations of 16,8,4 and 2 mg/L promoted the proliferation of T lymphocytes from lymph node,but was not obviously dependent on its concentration.Intraperitoneal injection of OMT increased the numbers of CD4+CD25+T cell in peripheral blood obviously(P

Objective To evaluate the value of captopril challenge test (CCT) in the diagnosis of primary aldosteronism (PA).Methods A total of 674 patients [(45.0±13.7) years, men 341, women 333] admitted to Peking Union Medical College Hospital from 2000 to 2015 were analyzed.Among them, 222 subjects were with essential hypertension (EH), 28 were with pheochromocytoma (PHEO), 246 were with idiopathic hyperaldosteronism (IHA) and 178 were with aldosterone producing adenoma (APA).All patients received CCT.24 h urine sodium was measured in partial patients.Plasma renin activity (PRA), aldosterone (ALD) were detected.Results Compared with EH [PRA: before 0.5(0.2,0.9) μg·L-1·h-1, after 0.8(0.4,1.5) μg·L-1·h-1;ALD: before (393±122) pmol/L, after (360±97) pmol/L] and PHEO [PRA: before 0.3(0.1,0.9) μg·L-1·h-1, after 0.4(0.1,1.6) μg·L-1·h-1;ALD: before (396±108) pmol/L, after (374±114) pmol/L], lower levels of PRA and higher levels of ALD before and after CCT were observed in PA patients [PRA: before 0.1 (0.1,0.2) μg·L-1·h-1, after 0.1 (0.1,0.2) μg·L-1·h-1;ALD: before (468±216) pmol/L;after (457±199) pmol/L].After CCT, the suppression rate of ALD [2.8% (-8.8%,15.4%) vs 6.6% (-4.3%, 17.6%)] and increasing rate of PRA [0(0,50%) vs 50%(0, 200%)] in PA patients were lower than those in EH patients.The ALD/PRA ratio (ARR) were higher in PA than that in EH or PHEO patients.In the EH subjects, ALD levels of seated posture were higher than those of recumbent posture both before and after receiving captopril, but with no changes in ARR after CCT.No significant differences in ALD and ARR (before and after receiving captopril) were observed between seated and recumbent position in the PA group.The ARR after CCT tended to decrease in EH subjects with elevated urine-sodium compared with those with normal urine-sodium.No changes could be viewed in ALD and PRA levels between normal urine-sodium and elevated urine-sodium groups among APA, IHA and EH patients either before or after CCT.Among patients with APA, the ALD levels before CCT and the ARR after CCT were lower in the patients with AngiotensionⅡ(AngⅡ) reactive than those without.A ROC curve analysis suggested that the optimal cutoff value was 46.2 (ALD unit:ng/dl;PRA unit:μg·L-1·h-1) for ARR after challenge in diagnosing PA, with the sensitivity of 88.7% and specificity of 84.8%.Conclusions ARR after 25 mg captopril had high sensitivity and specificity in diagnosis of PA with the cutoff of 46.2.Seated CCT could replace recumbent CCT as a more confirmatory test.The PRA increasing rate should be taken into consideration when diagnosis of PA.

OBJECTIVETo compare shear bond strength (SBS) between two types of silicone soft liner and polymethyl methacrylate (PMMA) under the condition of heat curing and room temperature curing.

METHODSA total of 48 PMMA specimens (50 mm x 10 mm x 3 mm) were made by water-bath heating method, and randomly divided into four groups. By using Ufi Gel P (UGP) as soft liner material, group A1 was prepared under heat curing, and group A2 was prepared under room temperature curing. To form the other two groups, Silagum-Comfort (SLC) as soft-liner material was used. Group B1 was prepared under heat curing, and group B2 was prepared under room temperature curing. Shear bond strength (SBS) was tested by using the electronic universal testing machine. The adhesives layer and surface of silastic and PMMA were observed by optical microscope and scanning electron microscopy (SEM).

RESULTSThe SBS of groups A1, A2, B1, B2 were (2.39 +/- 0.24), (1.74 +/- 0.27), (3.09 +/- 0.26), and (2.21 +/- 0.29) MPa, respectively. Significant differences were found between A1 and A2, B1 and B2, A1 and B1, and A2 and B2 (P < 0.05). Optical microscope showed numerous bubbles in the cured UGP, and no air bubbles in the SLC. The surface of PMMA was rough. SEM images showed that each group had continual consistent adhesive interface and a whisker hump on the adhesive layer of A2 and B2.

CONCLUSIONThe SBS ofUGP, SLC, and PMMA achieved minimum clinical standard of 0.44 MPa. The SBS of UGP and PMMA were higher than that of SLC and PMMA. The polymerization method of heat curing was higher than room temperature curing.

Objective To investigate MRI characteristics of subacute combined degeneration(SCD)with secondary spinal canal stenosis.Methods The clinical and MRI imaging data of 56 patients with SCD were collected to analyze the performance characteristics between spinal cord lesions and spinal canal stenosis,which depended on the synergism of lumbar disc bluge or herniation,degenerative thickening of the ligament flavum and posterior longitudinal ligament.Results Among 56 SCD cases underwent MRI scan,45 cases were combined with spinal cord lesions which showed typical signs of SCD.37 patients were secondary spinal canal stenosis with typical signs,but 2 showed no typical signs.8 patients were no secondary spinal canal stenosis and showed typical.9 cases showed neither spinal cord lesions nor secondary spinal canal stenosis.There was significant difference (P <0.05)between relative secondary spinal canal stenosis and spinal anomaly signal.The course of 1 5 cases were shortened after treated by physical in 37 cases of SCD with secondary spinal canal. Conclusion The secondary spinal canal stenosis can cause microcirculation dysfunction of the spinal cord,which is a key factor contributing to the imaging manifestation.

Objective To analyze the clinical features of patients with subclinical pheochromocytoma(PHEO).Methods Review of clinical features of 22 patients with subclinical PHEO treated in PUMC hospital from 1997 to 2007.Results All patients were asymptomatic.24hr-urinary catecholamine excretion was detected normal in 10 of 22 cases,while increased in the others.Sixteen patients were prepared with ?-receptor blocker before operation.During the operation,BPmax(maximal blood pressure) before tumor resection,BPmin(minimal blood pressure) after resection and ?BP(BPmax-BPmin) were(163?34)/(86?20)mmHg,(105?12)/(61?10)mmHg and(58?37)/(25?21)mmHg,Respectively,in the prepared group.They were(169?36)/(104?20)mmHg,(97?18)/(56?13)mmHg and(71?48)/(48?29)mmHg in the other 6 cases without ?-blocker preparation.DBPmax and ?DBP in the prepared group were significantly lower than the unprepared group.Conclusion Most patients with subclinical PHEO have increased catecholamine secretion.Blood pressure is fluctuant greatly during operation in some patients.Patients should be treated with ?-receptor blocker preoperatively in order to decreasethe operation risk.