Air Pollutants ; standards ; China ; Particulate Matter ; standards

Air Pollutants ; Air Pollution ; Humans ; Particulate Matter ; Public Health ; Smog

Adult ; Femur Head Necrosis ; chemically induced ; drug therapy ; Glucocorticoids ; therapeutic use ; Humans ; Male ; Paraquat ; poisoning

Adolescent ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Paraquat ; poisoning

Objective To observe the biomechanical changes of subchondral bone in the early stage of knee joint instability and effect of diphosphonate therapy so as to investigate the role of the early biomechanical changes of subchondral bone in the onset and development of osteoarthritis (OA).Methods Sixty healthy male New Zealand white rabbits were assigned to model group (n =24),diphosphonate group (n =24) and control group (n =12) according to random number table.Joint destabilization by anterior cruciate ligament transection of the right knee of the rabbits was performed to induce OA models.Rabbits in diphosphonate group received subcutaneous injection of 0.01 mg/kg diphosphonate (risedronate) per day,and isotonic saline solution of the same volume was subcutaneously given to rabbits in model and control groups.Half the animals in each group were killed by aeroembolism at postoperative 4 weeks and 12 weeks respectively.Surgical knee joint with preservation of each 2 cm bone above and below joint surface was dissected to perform gross scoring.Thereafter,two-dimensional image profile was achieved by Micro-CT examination and converted into Ansys for limit element analysis after fitting in Mimics software.Results At four weeks,bone volume fraction (BVF),elastic modulus (EM),reaction force (RF),and mean Von Mises stress were all declined in three groups,the lowest level in the model group (P ＜ 0.01).The diphosphonate group also had lower levels than the control group,with insignificant difference.Bone mineral density (BMD) in the model group was obviously declined in contrast with the diphosphonate and control groups (P ＜ 0.01),but there were no significant difference between the diphosphonate group and the control group.At 12 weeks,the model group showed higher level of BVF and BMD,but lower level of EM,RF and Von Mises stress in comparison with the control and diphosphonate groups (P ＜ 0.01).EM,RF,and Von Mises stress were lower in the diphosphonate group than those in the control group as well,but the difference was statistically insignificant.The model group showed that BVF,BMD,EM,RF,and Von Mises stress at 12 weeks were improved from those at 4 weeks (P ＜ 0.01).Conclusions Biomechanical properties of subchondral bone are affected in the early stage of knee joint instability and a notable decrease of EM is observed in the early stage,followed by an enhancement in late stage.It means that the biomechanical changes of subchondra,l bone in the early stage of knee joint instability may be connected with the bone resorption resulting from abnormal stress.On the contrary,diphosphonate may markedly improve EM of subchondral bone through inhibiting bone resorption.

Objective To observe the three-dimensional structure changes of subchondral bone in early stage knee joint instability and the effect of diphosphonate intervention so as to test the role of early three-dimensional structure changes of subchondral bone in pathogenesis of osteoarthritis (OA).Methods Sixty healthy male New Zealand white rabbits were assigned to model group (n =24),diphosphonate group (n=24) and control group (n =12) according to random number table.Rabbit right knee destabilization (anterior cruciate ligament transection) is used to induce OA.Rabbits in diphosphonate group received subcutaneous injection of 0.01 mg/kg diphosphonate (risedronate) per day.Instead,isotonic saline solution of the same volume was subcutaneously given to rabbits in model and control groups.One third of the animals in each group were killed at week 4,8 and 12 respectively.Surgical knee joint with preservation of each 2 cm bone above and below joint surface was dissected to perform Micro-CT.Bone volume fraction (BVF),trabecular thickness (Tb.Th),trabecular spacing (Tb.Sp),trabecular number (Tb.N),volumetric bone mineral density (vBMD) and tissue BMD (tBMD) were measured and analyzed statistically.Results At week 4 following operation,BVF,Tb.N and Tb.Th were lowered significantly in model group as compared to control group (P ＜0.01) ;BVF was lower in model group than in diphosphonate group (P ＜ 0.05) and lower in diphosphonate group than in control group (P ＜ 0.05) ; Tb.Sp was increased in model group as compared to diphosphonate group and control group (P ＜0.01) and had obvious increase in diphosphonate group as compared to control group (P ＜0.01) ; vBMD was significantly lower in model group than in diphosphonate group and control group (P ＜ 0.05),but there was no statistical difference between diphosphonate group and control group.At week 12 following operation,model group presented higher BVF,Tb.Th and Tb.N (P ＜0.05),significantly lower Tb.Sp (P ＜ 0.05) and significantly higher vBMD (P ＜ 0.01) as compared to diphosphonate group and control group.Conclusions In knee joint instability,variations of subchondral bone are mainly characterized by osteoclasia in the early stage,followed by osteogenesis in later stage.Diphosphonate may improve the bone architecture of subcondral bone via inhibition of bone resorption.

〔Abstract〕 By use of the decision tree algorithm and diagnostic indexes , the paper sets up the discrimination rules to make differential diagnosis of Primary Hepatocelluar Carcinoma ( PHC) based on basic data of 95 patients with PHC and 190 patients with liver cirrhosis , in-cluding the CT diagnosis, testing results of imaging and serologic markers such as the HbsAg , AFP, CEA and AFU, sex and age, etc.As indicated by the results , the data mining technology represented by the decision tree can support the differential diagnosis of PHC .

Bridged-Ring Compounds ; poisoning ; Humans ; Male ; Middle Aged ; Poisoning ; therapy ; Treatment Outcome

Objective To evaluate the clinical effect of absorbable self-enhancing cartilage nails in the treatment of radial head fractures.Methods Data of 22 patients with radial head fractures,who had undergone open reduction and internal fixation with absorbable self-enhancing cartilage nails from January 2008 to December 2011,were retrospectively analyzed.Among them,data of 18 patients were complete,including 10 males and 8 females.According to the Mason classification,there were 14 cases of Mason Ⅱ,3 cases of Mason Ⅲ and 1 case of Mason Ⅳ.Two patients were combined with radial neck fractures,9 with osteochondral fractures of capitellum,and 1 with posterior dislocation of the elbow and olecranon avulsion fracture.The radial head fractures were temporarily fixed with Kirschner wires after open reduction,then absorbable self-enhancing cartilage nails with length from 16 to 24 mm and diameters of 1.5 mm were applied to reach final fixation.The heads of nails were right underneath of cartilages without penetrating bone cortexes on the contralateral side.The radial neck fractures were reduced and fixed with T-plates or anatomical plates after the radial head fractures were fixed with cartilage nails.Four cases of osteochondral fracture of capitellum were fixed with absorbable sutures to external epicondyle of humerus.For other 5 cases of osteochondral fracture of capitellum,the bone fragments were removed due to too small to fix.Results All 18 patients were followed up for 6 to 54 months (average,31.3 months).All fractures achieved bone union,and the healing time ranged from 5 to 12 weeks (average,8.7 weeks).There were no complications,such as internal fixation failure,nonunion,hematoma,sinus formation,osteolytic changes of radial heads and so on.According to the Broberg-Morrey elbow performance score,13 cases were excellent,4 good,and 1 fair,with the total excellent and good rate of 94.44％ (17/18).At final follow-up,the elbow range of motion was 90° to 150° (average,123.8°),and the range of forearm rotation was 130° to 180° (average,152.5°).Conclusion Absorbable self-enhancing cartilage nails can be used to treat various kinds of radial head fractures,and the results are satisfactory.

Objective To do the epidemiological analysis based on the data of air fine particulate matter PM2.5 and daily mortality and to estimate the exposure-response relationship. Methods Based on the online search of relevant studies with the same endpoint meta-analysis was used to do the comprehensive assessment to determine the exposure-response relationship. Results The exposure-response relationship between short-term exposure to ambient PM2.5 and the increased percentage of daily mortality was found as the concentration of air fine particulate increased a certain degree(100 ?g/m3) the daily mortality of residents increased by 12.06%(95%CI 8.31%-15.82%). Conclusion The exposure-response relationship recommended in the present paper can be applied to the health risk assessment of air fine particulate matter in various cities of China.