Abstract: Objective To investigate the effects of haemopoietic stem cell mobilization on vein graft patency and intimal hyperplasia of anastomosis. Methods Twentyfour New Zealand rabbits were randomly divided into experimental group and control group, 12 rabbits in each group. A double side of carotid arteryvein transplantation model was made in each rabbit. One side of vein graft was digested by 0.25% trypsin for complete endothelial denudation before transplantation. Recombinant human granulocyte colonystimulating factor was given by subcutaneous injection 24 hours after operation, once per day in successive 10 days in experimental group, saline was given in the same way in control group. Bone marrow stem cells mobilization was observed after operation, including karyote counts and mononuclear cell proportion in peripheral blood. The patency rate of vein grafts and the degree of anastomosis intimal hyperplasia were observed too. Results The karyote counts (t=8.406,P=0.000)and mononuclear cell proportion(t=31.267,P=0.000) in peripheral blood of experimental group increased significantly 5 days after operation than those in control group. The vein grafts with intact endothelium had higher patency rate in both groups. In the vein grafts with complete endothelial denudation, the patency rate were obviously lower, but it was higher in experimental group than those in control group (67% vs. 30%). In the end of experiment, the pulsatility index of the vein grafts anastomosis with complete endothelial denudation was lower in experimental group than that in control group(t=2.958,P=0.009). Pathological examination showed that various degrees of intimal hyperplasia in all anastomoses of vein grafts were observed 4 weeks after operation. The degree of anastomosis intimal hyperplasia was more severe in vein grafts with complete endothelial denudation. Compared with control group, re-endothelization occurred completely in vein grafts with complete endothelial denudation of experimental group and the degree of anastomosis intimal hyperplasia was relatively lower (Plt;0.05). Conclusion Haemopoietic stem cell mobilization can provide protective effects on vein grafts by accelerating reendothelization which might increase vein grafts patency rate in the near future after operation and reduce anastomosis restenosis caused by intimal hyperplasia.
Objective To determine whether the number of distal locking bolts have an impact on the biomechanical feature of locking intramedullary nails. Methods Twenty locking nails tested were divided into two groups randomly. One distal locking screw was used in first group (single bolt group); and two were used in the other group (double bolts group). After being fixed in the model, compressive and torsional strength of the interlocking nail were measured in each group. Results The average maximum strength of double bolts group and single bolt group was 2 160 N and 1 880 N respectively in compression tests(P＜0.05). In torsion tests, the average maximum torsional moment of double bolts group and single bolt group was 55.8 Nm and 55.5 Nm respectively(P＞0.05), the average maximum torsional angle indouble bolts group and single bolt group was 58.3° and 58.0° respectively(P＞0.05). Conclusion Single distal bolt used in interlocking nail system can meet clinical request, though the whole biomechanical behavior isnot better than that of double bolts. One distal bolt is enough for the stable fracture types and double bolts should be used in the serious fracture types.
Based on the existing clinical research of pediatric Tuina, this paper introduced the current types of pediatric Tuina and their applications in the aspect of growth of newborn babies, emotion problems, pain, respiratory system diseases, digestive system diseases, jaundice, brain and nerve system diseases. As for the clinical researches of pediatric Tuina, the authors found the challenges including different understandings of pediatric Tuina, poor quality of clinical researches, and lack of basic data regarding pediatric Tuina. Meanwhile, the authors suggested three corresponding strategies to improve the clinical researches, i.e. to extract valuable intervention methods based on clinical practice; to conduct high quality clinical studies; to gradually collect and accumulate basic data according to a certain plan.
Objective To evaluate the sclerosing effects of several chemical sclerosants on the gallbadder mucosa in vivo. Methods Twentyeight rabbits were randomly divided into： Normal saline was used as contrast agent, and 95% ethanol, 5% tetracycline and compound phenol as sclerosants respectively. The cystic duct was ligated and cholecystostomy was performed for each animal. Sclerosants and contrast agent were injected into the gallbladder through a tube respectively and were kept in the gallbladder for 15 minutes. Animals were killed two weeks later; the gallbladder, bile duct and adjacent liver tissue were obtained for histopathological examination. Results With the naked eye, normal saline and 5% tetracycline made the cavity of the gallbladder unchanged; 95% ethanol made two gallbladder cavities occluded, two smaller, and three unchanged; and compound phenol made four gallbladder cavities occluded, and three smaller. In histopathological observations, 95% ethanol and compound phenol could make seven rabbits’ gallbladder mucosa completely destroyed (7/7); compared with normal saline (1/7), there was significant difference (P＜0.01). Five percent tetracycline had some effect of ablating the gallbladder mucosa (5/7), but compared with normal saline, there was no difference (Pgt;0.05). Conclusion Ninety-five percent ethanol can be clinically applied as an effective and safe sclerosant.
For tooth segmentation problem on the three-dimensional computed tomography (CT) volume data, this paper proposes a regional adaptive deformable model for tooth structure measurement of CT images. The proposed method combines the automatic thresholding segmentation, CV active contour model, and graph-cut. Firstly, we achieved the segmentation and location of dental crowns by automatic thresholding segmentation. And then by using the above segmentation result as the initial contour, we utilized active contour method to slice gradually the segment of remaining tooth. By incorporating active contour and graph-cut then, we realized the accurate segmentation for tooth root, which is the most difficult to be segmented. The experimental results showed that the proposed tooth structure measurement accurately and automatically segmented dental crowns from CT data, and then rapidly and accurately segmented the tooth neck and tooth root. The structure of tooth could be effectively segmented from CT data by using the proposed method. Experimental results indicated that the proposed method was rather robust and accurate, and could effectively assist the doctor for diagnosis in clinical treatment.