Objective To establish a respiratory distress syndrome (RDS) model of piglets and assess the therapeutic effect of pulmonary surfactant (PS) on gas exchange, lung mechanics and morphology. Methods Preterm newborn piglets were delivered by cesarean section at 94~97 days of gestation for determination of lung immaturity. Littermates were randomly divided into 4 groups: Group C50 were treated with 50 mg/kg for 6 h and group C100 with 100 mg/kg Curosurf; group C was the control group and group N received no ventilation. Blood-gas analyses and lung mechanic measurement were performed per hour. At the end of the experiment, the lungs were processed for biochemical, biophysical and histopathological analyses. Results Surfactant deficiency in RDS was shown with the low total phospholipids (TPL) level in bronchoalveolar lavage (BALF) in premature piglets at 94~97 days of gestation with marked difficulty in spontaneous respiration and morphological evidence of poor alveolar aeration and paucity of lamellar bodies in type Ⅱ alveolar epithelial cells. The group C had typical lung injury of RDS, the C100 and C50 group had variable but significantly improved alveolar phospholipid, alveolar aeration and wet-to-dry lung weight ratio. PaO_2/FiO_2 was improved from (92?37) mm Hg to (235?137) mm Hg, and the dynamic compliance (Cdyn) from (0.48?0.08) to (0.76?0.29) ml/(cm H_2O?kg) in group C100. But mild effects was shown in group C50. Conclusion A premature piglet RDS model is established and valuable for investigation of mechanism of lung injury in early life after born.

Full ceramic prosthesis is becoming the main prosthetic development direction. As an important kind of full ceramic prosthesis, full ceramic veneer has not only natural cosmetic appearance and perfect biocompatibility, but also can preserve tooth structure as much as possible, which would be more easily accepted by patients for cosmetic prosthesis. Many methods, such as slip casting, die casting and CAD/CAM technology are available to make full ceramic veneer. All the methods have their own advantages and disadvantages. Slip casting is easy to be developed widely with low cost, so be used in practical work. In this article, the working process of full ceramic veneer, especially manufacture of removable dies, duplication of refractory models, were introduced, which was supposed to be beneficial for the technicians.

Both with the advantages of fixed and removable dentures,the attachment prostheses is an important component of prosthodontics.At present,the resin base for the removable part of attachment denture was majorly made with traditional methods such as cartoning,resin-filling,heat treatment.But the produced fixed part of attachment denture was easy to be deformed or broken off during such processes.Here a method were introduced to produce resin base with injection moulding,which could avoid the occurrence of the mistakes of traditional methods and simplify the process.

BACKGROUND:Femoral neck fracture is mainly fixed by three inverted triangle cannulated screws. Scholars have proposed to add a cannulated screw to enhance the fixation strength of femoral neck fracture of Pauwels III type based on three cannulated screw fixation, but the stability is not verified. OBJECTIVE:To analyze the biomechanical stability and stress of the three and four cannulated screws for the treatment of the Pauwels III femoral neck fractures. METHODS:The CT imaging results of the fourth generation of artificial bone sawbones were imported into the Mimics software wherein a three-dimensional finite element model of the proximal femur was prepared and introduced in the 3-matic software. Models of middlesegment of femoral neck with Pauwels III fractures were established. Cannulated screw models were established with UG 8.0 software and introduced in the fractures models. Finally, finite element models of Pauwels III femoral neck fractures fixed with three and four screws were established. In the same condition, an axial load of 411 N was applied on the femoral head with Abaqus software. The displacement of two markers of the broken ends and internal fixation system Von Mises stress distribution were compared between the two models. RESULTS AND CONCLUSION:(1) The displacement was 0.42 mm in three screws model, and 0.17 mm in the four screws model. (2) Von Mises stress peak was 547 MPa and 27.8 MPa in both models. The peak value was lower in models of fourscrews than that of three screws. Stress concentration position was at the fracture site in both models. The stress range of models of four screws was more extensive and scattered. (3) Finite element analysis results demonstrated that four-screw implantation for Pauwels III femoral neck fractures had strong anti-shearing force and biomechanical stability. Clinical advantages need further clinical comparative study.

The low recovery of pertussis toxin (PT) and the low resolving efficiency of chromatography, due to the instability of PT in low salt condition, are the main challenges for its purification. We aplied 2 mol/L urea to prevent the aggregation and disassociation of PT during the purification by ion-exchange chromatography (IEC) and gel filtration chromatography (GFC). The effect of urea on the purification of PT was studied by ELISA assay and non-reduced SDS-PAGE. The activity recoveries of PT and filamentous hemagglutinin (FHA) in IEC and GFC, the resolution efficiency in GFC and the purities of PT and FHA were improved obviously by adding 2 mol/L urea in the mobile phase. The results highlight the potential application of urea in the acellular pertussis vaccine (APV) manufacture procedure.
Adhesins, Bacterial ; isolation & purification ; Chromatography, Ion Exchange ; methods ; Humans ; Pertussis Toxin ; isolation & purification ; Pertussis Vaccine ; chemistry ; isolation & purification ; Solutions ; Urea ; chemistry ; Vaccines, Acellular ; chemistry ; isolation & purification ; Virulence Factors, Bordetella ; isolation & purification

Objective To evaluate the application of flexible thoracoscopy in the diagnosis of pleural effusion.Methods Thoracoscopy was performed in 20 pleural effusion patients in our hospital from May to December 2007.Biopsies were performed in 16 patients,not in the other 4 patients since difinite diagnosis had been reached before thoracoscopy.Results Rate of accurate diagnosis via thoracoscopy was 93.75%(15/16).Results Of biopsy were as follows:adenocarcinoma 8 cases,squamous carcinoma 1 case,adenosquamous carcinoma 1 case,malignant pleural effusion 1 case,tuberculous pleuritis 4 cases,malignant mesothelioma 3 cases,chronic suppurative pleuritis 1 case,failed diagnosis 1 case.Presentations of lesions under thoracoscope were as follows:diffused miliary nodules 10 cases(10/20),multiple mass 7 cases(7/20),fibrous compartmentation or conglutination 9 cases(9/20).There were no severe complications.Conclusion Flexible medical thoracoscopy is a safe and efficient method of etiologic diagnosis of pleural effusion.

Objective The magnetic beads direct adsorption method was used to extract the cell-free DNA (cfDNA) from three kinds of human humoral biological samples, including urine, saliva and blood, as to provide a reference for forensic cfDNA research and forensic inspection. Methods The cfDNA was isolated from humoral samples by centrifuging, and the cfDNA was extracted with the method of magnetic beads direct adsorption. Then the samples were sequentially amplified with Identifiler-Plus amplication kit, and the STR genotyping was detected by ABI 3500 Analyzer. Results The cfDNA was detected from all the three kinds of samples. The detection rate of cfDNA from the blood samples was 100%, the saliva was 90%, and the urine was 70%. Conclusion The results suggest that human humoral biological samples contain cfDNA. What's more, the magnetic beads direct adsorption method can be used to extract cfDNA efficiently and conveniently.

ObjectiveTo analyze the characteristics of dysfunction in patients with chronic hip pain and clarify the relationship between dysfunction and psychological factors. MethodsA total of 55 patients with chronic hip pain admitted to the First Medical Center, Chinese PLA General Hospital from April, 2021 to March, 2022 were selected as experimental group, and 34 healthy subjects were selected as control group. The basic information and clinical data were collected by questionnaire. They were evaluated with the Hip Outcome Score Activities of Daily Living (HOS-ADL), the Hip Outcome Score sport-specific subscale (HOS-SSS), modified Harris Hip Score (mHHS), the 12-Item Short-Form Health Survey (SF-12), Visual Analogue Scale (VAS), Hospital Anxiety and Depression Scale (HADS including HADS: A and HADS:D), State-Trait Anxiety Inventory (STAI) and Pain Catastrophizing Scale (PCS), and their corelation with clinical indicators were analyzed. ResultsThe scores of mHHS、HOS-ADL、HOS-SSS and SF-12 were significantly lower in the experimental group than in the control group (|Z| > 6.251, P < 0.001). The scores of mHHS, HOS-ADL, HOS-SSS and SF-12 were negatived related with the score of Pain Catastrophizing Scale (PCS) (|r| > 0.480, P < 0.01). The risk factors of PCS were HADS:A, HADS:D and HOS-ADL. ConclusionThe functional level of patients with chronic hip pain is closely related to the catastrophic pain, and the influencing factors of catastrophic pain are anxiety, depression, and the motor function required for daily life of the hip joint.