Objective To study the effect of various doses of estrogen on tissue injury, blood supply and survival area of skin flap and to investigate its mechanism. Methods Thirty New Zealand white rabbits aged 3-4 months old and weighing 1.5-2.2 kg (male or female) were used. Random pattern skin flap (12 cm × 3 cm in size) taking the central l ine of the rabbit dorsum as axis and with the pedicle attached at the proximal end was prepared, and the flap pedicle division was performed 7 days after operation. The rabbits were divided randomly into three groups (n=10 rabbits per group). At 2, 4, and 6 days after operation, the proximal edge of flap in group A and B received 100 ?g/kg and 50 ?g/kg subcutaneous injection ofestradiol benzoate, respectively, while group C received no further treatment serving as control group. General condition ofthe rabbits was observed after injection, gross observation was performed 3 and 7 days after injection, survival area of the skin flap was measured 7 days after injection, contents of malondialdehyde (MDA) and nitric oxide (NO) were tested 5 days after injection, and the flaps were harvested 4 and 7 days after injection to receive histology and no significant difference was noted between group A and group B (P gt; 0.05). The NEU counts 4 days after injection were (18.20 ±6.24) cells/HP in group A, (21.27 ± 5.34) cells/HP in group B, and (28.78 ± 7.92) cells/HP in group C, and at 7 days after injection, there were (15.16 ± 7.02) cells/HP in group A, (18.12 ± 6.44) cells/HP in group B, and (29.67 ± 9.12) cells/HP in group C. The VEGF score 4 days after injection was (4.02 ± 0.48) points in group A, (4.19 ± 0.66) points in group B and (3.67 ± 0.49) points in group C, and at 7 day after injection, it was (4.96 ± 0.69) points in group A, (5.12 ± 0.77) points in group B, and (3.81 ± 0.54) points in group C. Significant difference was evident between 4 days and 7 days after injection in group A or B in terms of NEU counts and VEGF score (P lt; 0.05), and difference between 4 days and 7 days after injection in group C was not significant (P gt; 0.05), and the differences among 3 groups were significant (P lt; 0.05). Conclusion Estrogen injection can increase VEGF expression and NO content of flap, decrease MDA content and NEU infiltration of flat, and improve survival area of flap.
Objective To investigate the cl inical effect of Meek technique skin graft in treating exceptionally large area burns. Methods The cl inical data were retrospectively analysed from 10 cases of exceptionally large area burns treated with Meek technique skin graft from April 2009 to February 2010 (Meek group), and were compared with those from 10 casesof exceptionally large area burns treated with the particle skin with large sheet of skin allograft transplantation from January 2002 to December 2006 (particle skin group). In Meek group, there were 8 males and 2 females with an average age of 34.5 years (range, 5-55 years), including 6 cases of flame burns, 2 cases of hot l iquid burns, 1 case of electrical burn, and 1 case of hightemperature dust burn. The burn area was 82.6% ± 3.1% of total body surface area (TBSA). The most were deep II degree to III degree burns. The time from burn to hospital ization was (3.5 ± 1.3) hours. In particle skin group, there were 8 males and 2 females with an average age of 36.8 years (range, 18-62 years), including 5 cases of flame burns, 2 cases of hot l iquid burns, and 3 cases of gunpowder explosion injury. The burn area was 84.1% ± 7.4% of TBSA. The most were deep II degree to III degree burns. The time from burn to hospital ization was (4.9 ± 2.2) hours. There was no significant difference in general data between 2 groups (P gt; 0.05). Results The skin graft survival rate, the time of skin fusion, the systemic wound heal ing time, and the treatment cost of 1% of burn area were 91.23% ± 5.61%, (11.14 ± 2.12) days, (38.89 ± 10.36) days, and (5 113.28 ± 552.44) yuan in Meek group, respectively; and were 78.65% ± 12.29%, (18.37 ± 4.63）days, (48.73 ± 16.92) days, and (7 386.36 ± 867.64) yuan in particle skin group; showing significant differences between 2 groups (P lt; 0.05). Conclusion Meek technique skin graft has good effect in treating exceptionally large area burns with the advantages of high survival rate of skin graft, short time of skin fusion, and low treatment cost of 1% of burn area.
OBJECTIVE: To investigate the effect of subcutaneous tissue trimming on the survival skin area of avulsion skin flap. METHODS: Degloving injury was created in bilateral hind limbs of 7 pigs with avulsion injury machine, 4 cm x 10 cm avulsion skin flaps were elevated in degloving areas. Skin flaps in one side were replanted as control without any treatment. Subcutaneous tissue in the skin flaps of another side was partially excised and replanted by trimmed skin flaps. Survival skin flaps was calculated with computer at 7 days after operation. RESULTS: In the control group, the survival skin area was (40.41 +/- 9.23)%, while in the experimental group, the survival skin area was (60.90 +/- 15.26)%. There was significant difference between the two groups (P lt; 0.05). CONCLUSION: Trimming off subcutaneous tissue does improve the survival area of avulsion skin flap.
Objective To explore the program for calculating the necrotic articular surface area (NASA) and the ratio of NASA to whole articular surface area (WASA) of osteonecrosis of the femoral head (ONFH), to verify the accuracy of this calculation and to predict the collapse of the femoral head clinically using this program. Methods From June 2001 to June 2003, The specimens of the necrotic femoral head from eight patients (13 hips) were obtained by total hip arthroplasty. The magnetic resonance imaging (MRI) was taken in all patients before operation. According to a series of T1-weight pictures, the NASA and the ratio of NASA to WASA were calculated by designing program. The specimens of the necrotic femoral head were sawed into lays similar to MRI pictures using the coordinate paper stick on the auricular surface, the data processing were done by analytic instrument for pictures. The data of both were analyzed statistically by software SPSS 10.0 edition. The NASA and the ratio of NASA to WASA were calculated on MRI in ARCO Stage Ⅰ, Ⅱ 16 patients (25 hips) with non-operation. Follow-up was done to the patients with collapse of the femoral head and to the patients with no collapse for at least 24 months. The data were compared in collapse group and non-collapse group. Results There were no significant differences between MRI pictures calculation and specimens measurement (NASA: 0.412, ratio of NASA to WASA: 0.812, Pgt;0.05). Of the 25 hips followed up, collapse occurred in 17 hips. NASA was 31.06±8.10 cm2, (95% CI: 26.58 to 35.55)，the ratio of NASA to WASA was 58.91%±15.11%, (95% CI: 51.14to 66.68). No collapse appeared in 8 hips. NASA was 14.16±9.32 cm2(95% CI: 6.04 to 21.95), the ratio of NASA to WASA was 29.48%±19.76%(95% CI: 12.97to 45.99). The ratio in the patients with collapse was beyond 33%. Conclusion The NASA and the ratio of NASA to WASA in patients withONFH can be accurately calculated with the MRI pictures. The possibility of collapse can be predicted by this method. As it is complicated in operation, improvement should be made in order to put itinto clinical use.
Transcranial direct current stimulation (tDCS) is a brain stimulation intervention technique, which has the problem of different criteria for the selection of stimulation parameters. In this study, a four-layer real head model was constructed. Based on this model, the changes of the electric field distribution in the brain with the current intensity, electrode shape, electrode area and electrode spacing were analyzed by using finite element simulation technology, and then the optimal scheme of electrical stimulation parameters was discussed. The results showed that the effective stimulation region decreased and the focusing ability increased with the increase of current intensity. The normal current density of the quadrilateral electrode was obviously larger than that of the circular electrode, which indicated that the quadrilateral electrode was more conducive to current stimulation of neurons. Moreover, the effective stimulation region of the quadrilateral electrode was more concentrated and the focusing ability was stronger. The focusing ability decreased with the increase of electrode area. Specifically, the focusing tended to increase first and then decrease with the increase of electrode spacing and the optimal electrode spacing was 64.0–67.2 mm. These results could provide some basis for the selection of electrical stimulation parameters.
Objective To explore the effects of changes in the length of the patella on patellofemoral contact areas and pressures, to provide a theoretical foundation for treatment of lower pole of patella fracture. Methods Using homemadeloadingequipment, pressure sensitive films of 100 mm × 100 mm in size were placed on the force platform, vertically downwardload (0-19.6 N) was given. The pressure-sensitive response curve was obtained by computer image analysis of the pressuresensitive tablets and calculation. Six male left fresh knee specimens from voluntary donation were placed in homemade-test fixed load device, and the double-layer pressure sensitive film was placed on the patellofemoral joint surface; under loading of 196 N at flexion of 0, 15, 30, 45, 60, 75, 90, 105, 120, and 135° for 2 minutes, respectively, the pressure sensitive film was removed as the control group. Patellas were transected cut and in situ fixed by Kirschner wire and steel-wire as in situ fixation group. Bone fragments obtained from the corresponding 1/6 and 2/6 of contralateral patella, were embedded in the interspace between osteotomy with internal fixation with Kirschner wire and steel-wire respectively as lengthening group. Followed by the amputating patella length of 1/6, 2/6, 3/6 from proximal to distal and internal fixation with Kirschner wire and steel wire by turns as a shortening group. Repeat the above steps of each experiment. By image analysis the pressure sensitive film, the patella joint contact area were measured, and patellar contact pressure (including the peak pressure and average pressure) was calculated according to pressure-sensitive response curve. Results The actural contact area were significantly smaller in the shortening groups than in the control group at flexion of 30-135° (P lt; 0.05); the pressure was significantly bigger in shortening 1/6 group at flexion of 0, 15, 60, and 75°, in shortening 2/6 group at flexion of 0° and 75-135°, and in shortening 3/6 group at flexion of 0-30°and 75-135° than in the control group (P lt; 0.05); the peak pressure was significantly bigger in shortening 1/6 group at flexion of0, 15, and 60-105°, in shortening 2/6 group at flexion of 0, 15, and 75-105°, and in shortening 3/6 group at flexion of 0, 30, and 60-135° than in the control group (P lt; 0.05). The actural contact area was significantly smaller in the lengthening groups than in the control group at flexion of 15, 60, and 90°, and it was bigger at flexion of 105, 135° in lengthening 2/6 group than in the control group (P lt; 0.05); the pressure was significantly bigger in the lengthening groups at flexion of 15-75° than in the control group and it was smaller in the lengthening groups at flexion of 105, 135°, and smaller in lengthening 2/6 group at flexion of 120° (P lt; 0.05); the peak pressure was significantly smaller in lengthening 1/6 group than in the control group at flexion of 0, 90, and 105° and smaller in lengthening 2/6 group at flexion of 0° (P lt; 0.05). The actural contact area was significantly bigger in all lengthening groups than in all shortening groups at flexion of 30, 45, and 75-135° (P lt; 0.05). The pressure was significantly bigger in shortening 1/6 group than in lengthening groups at flexion of 0, 60, and 90° (P lt; 0.05), in shortening 2/6 group at flexion of 0, 60, and 90-120° (P lt; 0.05), in shortening 3/6 group at flexion of 0-135° (P lt; 0.05). The peak pressure was bigger in shortening groups than in lengthening 1/6 group at flexion of 0, 90, and 105° (P lt; 0.05), bigger than lengthening 2/6 group at flexion of 0° (P lt;0.05余请见正文.....
Objective To investigate the risk factors, clinical features and outcomes of patients with large hemispheric infarction (LHI), and explore the association between TOAST classification and LHI. Methods We prospectively registered consecutive cases of acute ischemic stroke at the neurological wards of West China Hospital, Sichuan University from January 1st 2010 to February 29th 2012. We collected the demographic data, risk factors, and other related data, assessed the National Institutes of Health Stroke Scale (NIHSS) and Glasgow Coma Scale (GCS) scores at admission, and followed-up the Modified Rankin Scale (mRS) scores at the third month from the onset. In different TOAST classifications, univariate analysis and multivariate analysis were used to find predictors for the occurrence and prognosis of LHI. Results Of the enrolled 1 729 patients with acute ischemic stroke, 317 (18.3%) had LHI. The multivariate analysis showed that male, hypertension and onset to admission time were the independent predictive factors for the large-artery atherosclerosis type LHI (P<0.05); atrial fibrillation and valvulopathy were the independent predictive factors for cardioembolism type LHI (P<0.05). Meanwhile, age, hypertension, onset to admission time, and NIHSS and GCS scores at admission were the independent predictive factors for death/disability (mRS>3) within three months (P<0.05). Conclusions Hypertension, gender, onset to admission time, atrial fibrillation, and valvulopathy are independently associated with the occurrence of LHI. Young patients with lower GCS, higher NIHSS scores and no hypertension are more likely to have a better prognosis after LHI.
Objective To compare the efficacy of reteplase and ateplase in the treatment of acute massive pulmonary thromboembolism ( PTE) in emergency. Methods From January 2005 to December 2009,42 patients with acute massive PTE were treated by intravenous thrombolysis with reteplase or ateplase. The thrombolysis efficacy, bleeding incidence and mortality were measured. Results In the reteplase group, the emergency thrombolysis effective rate was 88. 9% among 18 patients. Mild bleeding occurred in 3 patients,moderate bleeding in 1 patient, and 2 cases died in hospital. In the ateplase group, the emergency thrombolysis effective rate was 75% among 24 patients. Mild bleeding occurred in 3 patients, moderate bleeding in 2 patients, and 3 cases died in hospital. The thrombolysis effective rate, bleeding incidence and mortality had no significant difference between the two groups. Conclusion Both the reteplase and ateplase thrombolysis therapy are safe and effective in the treatment of acute massive PTE, but reteplase thrombolysis therapy is more convenient in emergency.
Objective To observe the midterm haemodynamic manifestation of the home made C-L pugestrut tilting disc mechanical valve in aortic valve replacement, and to evaluate its function. Methods Twenty patients underwent aortic valve replacement over 5 years were collected and divided into two groups, the C-L pugestrut group （n=10）：aortic valve was replaced by home-made C-L pugestrut tilting disc mechanical valve（21mm）; Medtronic-Hall group （n=10）：aortic valve was replaced by Medtronic-Hall mechanical valve （21mm）. The peak transprosthetic gradients （△P）, mean transprosthetic gradients （△Pm）and effective orifice area（EOA） at rest were compared between two groups. Results At rest, △P of the C-L pugestrut group and Medtronic-Hall group were 11.63±3.23mmHg vs. 9. 78±3. 35mmHg; △Pm of the C-L pugestrut group and Medtronic-Hall group were 6. 25±2. 32 mmHg vs. 5.85±2.32mmHg： EOA of the C-L pugestrut group and Medtronic-Hall group were 1.07±0.17 cm2 vs. 1.25±0.27 cm2. There was no statistically significance in △P, △Pm and EOA between two groups（P〉0.05）. Conclusions The midterm haemodynamic results of the home-made C-L pugestrut tilting disc mechanical valve show that it has comparable haemodynamic results to those of Medtronic-Hall mechanical valve ,and it has well-done function. The home-made C-L pugestrut valve is one of the reliable mechanical heart valves.
The material properties and volume proportion of the fibers as well as the cross-sectional area proportion of nucleus pulposus vary greatly in different studies. The effect of these factors on the mechanical behavior of intervertebral discs (IVDs) are uncertain. The IVDs finite element models with different parameters were created to investigate the pressure, height, rotation, stress, and strain of the IVDs under loads: pure compression, rotation after compression or axial moment after compression. The results showed that the material properties of fibers had great impact on the mechanical behavior of IVDs, especially on the rotation angle. When the fiber volume ratio was small, its changes had a significant impact on the rotation angle of the IVDs. The area proportions of nucleus pulposus had relatively little effect on the mechanical behavior of IVDs. The IVDs rotation should be observed when validating the model. By adjusting the elastic modulus or volume ratio of fibers within a reasonable range, a model that could simulate the mechanical behavior of normal IVDs could be obtained. It was reasonable to make the area proportion of nucleus pulposus within 25%–50% for the IVDs finite element model. This study provides guidance and reference for finite element modeling of the IVDs and the investigation of the IVDs degeneration mechanism.