Perioperative monitoring of blood coagulation is critical to better understand causes of hemorrhage, to guide hemostatic therapies, and to predict the risk of bleeding. Point-of-care (POC) coagulation monitoring devices assessing the viscoelastic properties of whole blood may overcome several limitations of routine coagulation tests in the perioperative setting. The advantage of these techniques is that they have the potential to measure the clotting process, starting with fibrin formation and continue through to clot retraction and fibrinolysis at the bedside, with minimal delays. Furthermore, the coagulation status of patients is assessed in whole blood, allowing the plasmatic coagulation system to interact with platelets and red blood cells, and thereby providing useful additional information on platelet function. Viscoelastic POC coagulation devices are increasingly being used in clinical practice, especially in the management of patients undergoing cardiac and liver surgery, assessment of hypo-and hypercoagulable states, guiding pro- and anticoagulant therapies, monitoring of antiplatelet therapy and procoagulant therapy. To ensure optimal accuracy and performance, standardized procedures for blood sampling and handling, strict quality controls and trained personnel are required.
Objectives
To estimate the elasticity of demand price elasticity and demand income of urban and rural residents’ self-purchase drug use and expenditure, and to analyze the sensitivity of self-purchase drug use and expenditure to the price change of drug purchase, resident income and medical institutions.
Methods
The data were derived from the fifth health service survey in Heilongjiang province in 2013. The Probit model was used to obtain the partial regression coefficients of the control variables in the regression model, and the demand elasticity of the self-purchase drug use was further measured by the partial regression coefficients, and the demand elasticity of self-purchase expenditure was obtained by the logarithmic regression model.
Results
A total of 5 289 households (14 431 persons) were included. The demand for self-purchase drug use of Heilongjiang province was 0.374 (P=0.000), the cross-price elasticity of self-purchase drug utilization and service was –0.184 (P=0.000), and the income elasticity was 0.083 (P=0.172). Since the price elasticity of the self-purchase drug expenditure was 0.675 (P=0.000), the income elasticity was 0.144 (P=0.069).
Conclusions
The use of self-purchased drugs in Heilongjiang province lacks price elasticity and is a necessity. There is a complementary relationship between the use of self-purchase drugs and medical institutions.
Polydimethylsiloxane (PDMS) and hydroxyapatite (HA) were combined in our laboratory to fabricate an elastic porous cell scaffold with pore-forming agent, and then the scaffold was used as culture media for rat bone marrow derived mesenchymal stem cells (rBMSCs). Different porous materials (square and circular in shape) were prepared by different pore-forming agents (NaCl or paraffin spheres) with adjustable porosity (62%-76%). The HA crystals grew on the wall of hole when the material was exposed to SBF solutions, showing its biocompatibility and ability to support the cells to attach on the materials.
【Abstract】 Objective To explore the midterm efficacy of superelastic cage implantation for the treatment of osteonecrosisof femoral head (ONFH). Methods From July 1996 to January 1998, 54 patients (75 hips) of ONFH were treatedwith superelastic cage and followed up. Among 54 patients, 5 patients were lost to follow up and 3 patients were dead of myocardialinfarction, renal failure and gastric cancer, respectively. Forty-six patients completed follow up including 32 males and14 females, aged from 21 to 61 with an average of 39 years old. Twenty-nine hips were classified as Ficat Stage Ⅱ and 36 as StageⅢ . Harris score was 58.20 ± 13.82. All patients were evaluated both cl inically and radiographically. Results Postoperatively,forty-six patients (65 hips) were followed up for 86 to 125 months with an average of 8 years and 8 months. Harris score was 80.78 ± 18.77. Twenty-nine hips were rated excellent, 21 good, 2 fair and 13 poor．A total of 76.9% of overall cl inical results were rated as good or excellent. Eight hips (12.3%) with the cage broken were turned to total hip replacement. Radiographicevaluation: 16 hips (24.6%) rated as grade Ⅰ , 34 (52.3%) grade Ⅱ and 15 (23.1%) grade Ⅲ . Conclusion Superelastic cage implantation is one of alternative treatments for ONFH at early and midterm stages. However, long-term follow-up is needed to know whether it is able to cure ONFH and whether cages will be broken as time passes by.
The mechanical properties of the cornea in corneal ectasia disease undergo a significant reduction, yet the alterations in mechanical properties within distinct corneal regions remain unclear. In this study, we established a rabbit corneal ectasia model by employing collagenase II to degrade the corneal matrix within a central diameter of 6 mm. Optical coherence tomography was employed for the in vivo assessment of corneal morphology (corneal thickness and corneal curvature) one month after operation. Anisotropy and viscoelastic characteristics of corneal tissue were evaluated through biaxial and uniaxial testing, respectively. The results demonstrated a marked decrease in central corneal thickness, with no significant changes observed in corneal curvature. Under different strains, the elastic modulus of the cornea exhibited no significant differences in the up-down and naso-temporal directions between the control and model groups. However, the cornea in the model group displayed a significantly lower elastic modulus compared to the control group. Specifically, the elastic modulus of the central region cornea in the model group was significantly lower than that of the entire cornea within the same group. Moreover, in comparison to the control group, the cornea in the model group exhibited a significant increase in both creep rate and overall deformation rate. The instantaneous modulus and equilibrium modulus were significantly reduced in the model cornea. No significant differences were observed between the entire cornea and the central cornea concerning these parameters. The results indicate that corneal anisotropy remains unchanged in collagenase-induced ectatic cornea. However, a significant reduction in viscoelastic properties is noticed. This study provides valuable insights for investigating changes in corneal mechanical properties within different regions of ectatic corneal disease.
Objective
To investigate the effectiveness of ulnar shortening osteotomy combined with elastic suspension fixation for ulnar impaction syndrome caused by relatively long ulna.
Methods
Between October 2015 and August 2016, 3 cases of ulnar impaction syndrome were treated. One patient was male and 2 patients were females. The age was 32, 29, and 59 years, respectively. One patient was dislocation and impaction of distal radioulnar joint for more than 1 year after internal fixation due to ulnar and radial open fractures. Other patients had no trauma and surgery, but long-term manual history. The visual analogue scale (VAS) scores were 7, 5, and 5, respectively. Cooney wrist function scores were rated as poor. Preoperative X-ray measurements of the ulnar variance was 12.7, 9.0, and 8.7 mm, respectively. The ulna was transversely osteotomy and fixed with plate and screws. The distal radioulnar joint was elastic suspension fixed with mini plate.
Results
Postoperative X-ray film showed that the matching of the distal radioulnar joint had no significant difference compared with the contralateral side. All the incisions healed by first intention without complication such as neurovascular injury, infection, and dislocation of the distal radioulnar joint. The patients were followed up 27, 17, and 23 months, respectively. At last follow-up, X-ray film showed that all osteotomy segments achieved bony union without internal fixation failure. The VAS scores were 2, 0, and 1, respectively, and the Cooney wrist function scores were rated as excellent.
Conclusion
The ulnar shortening osteotomy combined with elastic suspension fixation can correct the ulna variation, avoid the instability of the distal radioulnar joint caused by the extensive dissection of the tissue around the ulnar, and avoid stiffness of the joints caused by rigid fixation. It is an ideal treatment for ulna impaction syndrome.
Intravascular optical coherence tomography (IVOCT) has emerged as a high-resolution and minimal-invasive imaging technique that provides high-speed visualization of coronary arterial vessel walls and clearly displays the vessel lumen and lesions under the intima. However, morphological gray-scale images cannot provide enough information about the tissue components to accurately characterize the plaque tissues including calcified, fibrous, lipidic and mixed plaques. Quantitative IVOCT (qIVOCT) is necessary to provide the physiological contrast mechanisms and obtain the characteristic parameters of tissues with clinical diagnostic value. In this paper, the progress of qIVOCT is reviewed. The current methods for quantitatively measuring optical, elastic and hemodynamic parameters of vessel wall and plaque tissues using IVOCT gray-scale images and raw backscattered signals are introduced and potential development is forecast.
ObjectiveTo summarize the research progress in creep characteristics of lumbar intervertebral disc.MethodsThe relevant literature at home and abroad was systematically searched. Then, the concept and structural basis of lumbar disc creep, the description of creep characteristics, and the latest progress of its influencing factors were summarized and analyzed.ResultsThe intervertebral disc is viscoelastic. After loading, the deformation increases with time. However, the degree of increase is not linear with time. That is creep, which plays an important role in buffering the load generated by human activities and absorbing energy in order to maintain stable movement of the spine. Both experimental and simulation studies can well describe the creep behavior of intervertebral disc. Various models including standard linear solid model and corresponding constitutive equations can quantify and compare the creep characteristics, which can be obviously changed by the degeneration of intervertebral disc and the mode of loading stress.ConclusionCreep is an important mechanical properties of intervertebral discs, and an in-depth understanding of the creep characteristics of lumbar intervertebral discs is of great guiding significance for the intervention and treatment of low back pain.
Objective To find a simple, practical and cheap way in suturation to prevent incision complications after celoscope surgery. Methods Using the elastic snell needle to stitch small incision under laparoscopy. Chosed 3 120 cases using the elastic snell needle to stitch stratified suturation as research group, and 3 120 cases by using trditional arc shaped needle in celoscope surgery as control group. The incident rate of incisional hernia and incision bleeding among groups were compared. Results In research group, the incident rate of incision bleeding was 0.16%, among which was 0.15% in epigastrium group, 0.18% in hypogastrium group, while in control group, the incident rate of incision bleeding was 0.68%, among which was 0.64% in epigastrium group, 0.70% in hypogastrium group. The incident rate of incision bleeding was obviously decreased (P＜0.05), and the incident rate of incision bleeding in hypogastrium group was obviously decreased as well (P＜0.05), compared research group and control group. In research group, the incident rate of incisional hernia was 0.07%, among which was 0 in epigastrium group, 0.12% in hypogastrium group, 0.15% in gerontism group, while in control group, the incident rate of incisional hernia was 0.44%, among which was 0.24% in epigastrium group, 0.59% in hypogastrium group, 0.99% in gerontism group, and the incident rate of incisional hernia after surgery was obviously decreased (P＜0.05), the incident rate of incisional hernia after surgery in hypogastrium group was obviously decreased as well (P＜0.05), comparing research group and control group. Conclusions Using the elastic snell needle to stitch small incision under laparoscopy, the peritoneal layer and muscular layer can be apposition sutured in the case without prolonging incision and costing more, hidden hernia and abdominal wall defects located at the incision can be found, ligation and stitched, thereby the incident rate of incisional hernia and incisional bleeding after celoscope surgery are significantly reduced.
In the present study, swine thighbone samples with different water contents were prepared through process of dehydration. The influence of water content on the biotribological behavior of the bone tissue was studied with nanoindentation test, reciprocating sliding test and impact wear test. It is shown that the water contents had significant influence on the mechanical properties and biotribological behavior of the swine thighbone samples. In this experiment condition, with decreasing water content, the hardness and elastic modulus of the swine thighbone samples increased, while the tribological properties significantly decreased. The viscoelasticity of bone tissue decreased with decreasing water content, which mainly resulted in different wear mechanisms of the bone tissue samples under applied loading.
