The effect of intraosseous graft length on tendon-bone healing in anterior cruciate ligament reconstruction using flexor tendon

The current study was performed to understand the relationship between graft length placed within the bone tunnel and intraosseous graft healing in anterior cruciate ligament (ACL) reconstruction. Twenty-four adult beagle dogs were divided into two groups of 12 animals each. In each animal, ACL reconstruction using a 4-mm diameter autogenous flexor tendon graft was done in the left knee. In groups I and II, the graft having a length of 15 and 5 mm, respectively, was placed within the tibial tunnel. The proximal end of the graft was placed through the over-the-top route in all animals. In each group, five animals were sacrificed immediately after surgery, and the remaining seven were sacrificed at 6 weeks postoperatively. Biomechanical and histologic evaluations were performed. In pull out testing, the ultimate failure load and the linear stiffness of the graft-tibia complex harvested at 6 weeks were significantly greater than those harvested at the time-zero period. There were no significant differences in those parameters between groups I and II at 6 weeks. In each group, the perpendicular collagen fibers connecting the tendon to the bone tunnel wall were observed only in the narrow area located close to the intra-articular tunnel outlet. In conclusion, excessively long placement of the flexor graft within the bone tunnel does not result in an additional increase of anchoring strength and stiffness of the graft in ACL reconstruction.     

MRI的选购定位

对MRI若干主要参数进行总结,结合实际应用体会,对我院MRI设备选购进行讨论,以期对MRI设备的选购定位提供参考.     

Incisional healing in rats treated with diethyl maleate

Diethyl maleate (DEM) which binds and thus depletes tissue glutathione levels was used to aggravate the injury and to determine its effect on incisional healing. A 5 cm dorsal midline skin incision was performed on 40 albino Wistar rats in two groups and then closed by interrupted sutures. Groups received 0.9% NaCl and DEM at a dosage of 1 mg/kg/day intraperitoneally for seven days, respectively. On postoperative days 7 and 14, histopathological assessment and tensile strengths were measured. The DEM treated group had a marked inflammation with poorly defined collagen formation and the tensile strength measurements revealed a significant decrease (p <0.001) on the 7t day. On the other hand, the first group showed better collagenization and a lesser degree of inflammation. However, on the 14th day, there was no noticeable histopathological difference between the two groups; but, tensile strength values of the second group were still lower (p <0.05). In this animal model, DEM postponed the healing process and reduced the tensile strength.     

试论新世纪初期医院综合院力评价

作者阐述了医院综合院力的内涵与提出背景，提出了新世纪初期综合院力的评价内容体系，即一级评价内容7项，二级评价内容39项，三级评价内容15l项，并就各指标评价内容进行了讨论分析。     

N—酰化壳聚糖膜性能的研究

讨论了一系列N-酰化壳聚糖膜的抗张强度、透水性、VB_(12)的透过性、透氧性以及血液相容性。N-已酰化壳聚糖膜具有良好的血液相容性。在制膜过程中,加入分子量为1500的聚乙二醇为致孔剂,则可使N-己酰化壳聚糖膜的渗透性有较大提高。同时保持较好的血液相容性和强度。     

Effects of Clodronate on Cortical and Trabecular Bone in Ovariectomized Rats on a Low Calcium Diet

The aim of this study was to evaluate the contribution of a low calcium diet to the cortical and trabecular osteoporosis seen in ovariectomized rats after 7 weeks on a low calcium diet and to investigate the effects of the bisphosphonate clodronate on this development of osteoporosis. Thirty-six mature, female Wistar rats were randomized into four groups: Ovx−B (bisphosphonate) and Ovx−C (control) were ovariectomized, and Sham−Ca (low calcium) and Sham+Ca (normal calcium) were sham operated. The first three groups were fed a low calcium diet (0.01%) and Sham+Ca normal rat chow (Ca 1.1%). The Ovx−B received 10 mg/kg s.c. clodronate daily for nine weeks, and Ovx−C, Sham−Ca, and Sham+Ca received the same volumes of saline. Bone mineral turnover measured as ⁸⁵Sr-uptake was increased in all low calcium groups compared to Sham+Ca. The Sham+Ca femora had higher dry weight and ash weight than the other groups, and Ovx−C had higher dry weight compared with Ovx−B and Sham−Ca. Calcium content was lower in both Ovx groups compared to both Sham groups. Magnesium was lower in all groups compared to Sham+Ca and higher in Ovx−B compared with Ovx−C. In the femoral shaft, Sham+Ca had significantly higher ultimate bending moment, energy absorption, and deflection compared to the other three groups. Ultimate bending moment was higher in Sham−Ca than in Ovx−C. Stiffness was increased in both Sham+Ca and Ovx−B compared to Ovx−C. The maximum stress in the femoral midshaft was higher in Sham+Ca than in the other groups, and higher in Ovx−B than in Ovx−C. Histomorphometry showed increased medullary area in all low calcium groups compared to Sham+Ca and larger cortical area in Sham+Ca and Ovx−B compared to Ovx−C. Compared to Sham+Ca the trabecular bone volume was decreased to 30% in Sham−Ca and to 9% in Ovx−C, but was unchanged in Ovx−B. The low calcium diet generally increased bone mineral turnover and reduced the tibial bone volume. Femoral changes led to a reduction of cortical fracture strength and maximal stress. Ovariectomy in addition to a low calcium diet reduced femoral strength even more. Daily injections of clodronate to ovariectomized rats on a low calcium diet increased femoral shaft stiffness and maximum stress, and clodronate preserved both trabecular and cortical tibial bone volume completely. Received: 11 June 1996 / Accepted: 5 March 1997     

Arm function after axillary dissection for breast cancer: a pilot study to provide parameter estimates.

Sixty-three women participated in a study in Calgary, Alberta to assess the rate of arm recovery and factors affecting it up to one year after axillary node dissection for breast cancer. Outcomes included objective measures of swelling, mobility, and strength, and subjective assessments of pain (at rest and with movement) and stiffness. Approximately 42% of women had residual impairment of at least one type one year after surgery, the most common problems being pain (16%) and reduced grip strength (16%). Except for lymphedema, measurements one year after surgery showed little change from measurements at 6 months, suggesting that the shorter follow-up may be appropriate for assessing the long term effects of axillary dissection. Lymphedema was the only sequela which increased over time. The results provide parameter estimates for designing studies to evaluate the role of physiotherapy after axillary dissection.