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121.
During various knee operations, the changes caused by the surgical invasion to the infrapatellar fat pad (IPF) is still unknown. If any changes exist, it will have great influence especially on growing generations. Eighty-four Japanese white rabbits (6-month-old) were divided into three groups: the resection group involving resection of the IPF, the graft group involving resection and reimplantation of the IPF, and the no-surgery group. All these surgical procedures were done in right knees. In all left knees, only arthrotomy was performed, serving as the sham side. After 3, 6, 12, and 24 weeks of the operation, the rabbits were killed. Lengths of the patellar tendon and patellar were measured in lateral X-ray. In order to eliminate individual differences in the patellar height, we defined a new index as percent patellar height (PPH) which indicated the percentage of the patellar height of surgery side compared with that of the sham side. The PPH was 90.6% (3 weeks), 83.0% (6 weeks), 73.6% (12 weeks), and 74.7% (24 weeks) in the resection group, while it was 88.4% (6 weeks), and 88.9% (24 weeks) in the graft group. Postsurgical scar tissue formation occurring where the IPF was removed prevented the normal growth of the patellar tendon. Reimplantation of the IPF lessened the adhesion of the patellar tendon to the surrounding tissue, and better growth of the tendon. These results showed that preservation of the IPF in young individuals could be crucial for the normal growth of the patellar tendon, and critical as well for the prevention of the degeneration of the articular surface.  相似文献   
122.
123.
We examined the cell biological characteristics of a human embryonal carcinoma cell line. NEC 14, derived from a male germ cell tumor of testis origin. The following results were obtained. 1) The morphological characteristics of NEC 14 cells were small size, an increase in the N/C ratio and poor development of organelle and desmosome-like cell-cell junctions. The NEC 14 cells proliferated rapidly and the population doubling time in vitro was 17 hours. 2) The functional characteristics of NEC 14 cells were the localization of intermediate filaments such as keratin and vimentin, hCG secretion and tissue plasminogen activator and laminin synthesis and expression of cell surface antigens such as stage-specific embryonic antigen-3, trophoblast antigen and neuron cell surface antigen. 3) The mode of chromosome number was 58 and many abnormal and undetermined chromosomes were found in the NEC 14 cells. 4) Differentiation was observed in vitro and in the tumor tissues xenotransplanted into nude mice.  相似文献   
124.
Synovial fluid from osteoarthritic knee contains mesenchymal stem cells (MSCs). One of the possible reservoirs of MSCs in synovial fluid is synovial tissue, and synovial fluid may induce mobilization of MSCs into synovial fluid in osteoarthritis patients. Here, we investigated whether synovial fluid expanded synovial MSCs in a tissue culture system. Human synovium and synovial fluid were obtained from osteoarthritis patients during total knee arthroplasties. In the tissue culture system, autologous synovial fluid expanded synovial cells statistically higher than αMEM + FBS, and the addition of TGFβ3 to αMEM + FBS increased expansion to a similar level in all 11 donors. The addition of decorin or anti‐TGFβ neutralizing antibody to synovial fluid partially inhibited synovial cell expansion. In cell culture assay, synovial fluid proliferated synovial cells fewer than αMEM + FBS. The expanded synovial cells in synovial fluid retained multipotentiality and showed surface markers similar to those of MSCs. We demonstrated that autologous synovial fluid enhanced expansion of MSCs in tissue culture of synovium from osteoarthritis patients by promoting cell migration. This effect was partially affected by TGFβ. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1413–1418, 2008  相似文献   
125.
The sensitivity to actinomycin-D (Act-D) and the changes in survival rate of two human choriocarcinoma cell lines (BeWo and SCH) were studied in vitro and the following results were obtained. BeWo was shown to be more sensitive to Act-D than SCH, when the survival rate was compared in the two cell lines. 3H X Act-D uptake was 39 pmol/10(6) cells in BeWo and 12 pmol/10(6) cells in SCH after a two hours treatment. Those results suggested that the sensitivity to Act-D of choriocarcinoma cells was positively correlated with the intracellular Act-D concentration. The intracellular Act-D concentration was increased depending upon the concentrations of amphotericin B (AMB). After a two hours treatment with Act-D and AMB, the intracellular Act-D concentrations were twice in BeWo, and 2.3 times in SCH comparing with those treated with Act-D alone. The synergistic effects of Act-D and AMB on the survival rate were 1,000 times in BeWo and 100 times in SCH compared with those treated with Act-D alone. From the above, combination therapy with Act-D and AMB was supposed to be one of the trial methods in the treatment of drug resistant choriocarcinoma.  相似文献   
126.
MCC-478 is a newly synthesized 2-amino-6-arylthio-9-phosphonomethoxyethylpurine bis(2,2,2-trifluoroethyl) ester derivative. MCC-478 showed a substantially higher (ca. 80-fold) anti-hepatitis B virus (HBV) activity than that of lamivudine, despite no significant anti-human immunodeficiency virus activity. Since the bis(2,2,2-trifluoroethyl) ester group was used to improve the oral bioavailability of the phosphonomethoxyethylpurine derivatives, two monoester derivatives and one phosphonic acid derivative were also evaluated. It was suggested that these hydrolyzed derivatives, which appeared in animals given MCC-478, have enough anti-HBV activity to contribute to efficacy in vivo. Furthermore, no apparent cytotoxic effects or reductions of mitochondrial DNA content by MCC-478 and its derivatives were observed. These results indicated that MCC-478 may be a new promising anti-HBV agent.  相似文献   
127.
Erythrocyte membrane proteins of a hereditary spherocytosis patient with a severe anemia were analysed by SDS-disc electrophoresis according to the method of Fairbanks et al. A defective protein band IVb was found. Surface features of the patient's red cells were examined by scanning electron microscopy which showed many deformed erythrocytes with peculiar shape. The lipid composition of erythrocyte membranes from hereditary spherocytosis was not changed.  相似文献   
128.
Pediatric intrasubstance posterior cruciate ligament (PCL) injuries are rare but present a significant treatment challenge. Untreated instability may lead to further knee injury, including meniscal or chondral damage. Surgical intervention risks damage to the physis, growth arrest, and angular deformity. We present the case of a skeletally immature 11-year-old boy with a high-grade intrasubstance PCL injury reconstructed using an all-arthroscopic tibial inlay technique modified to minimize risk of physeal injury. The femoral tunnels were placed entirely within the epiphysis, and the tibial physis was minimally crossed with a small drill hole and suture material. At 17 months' follow up, the patient had returned to full activity, including sports. He had a grade 1 posterior drawer and no posterior sag. Radiographs showed no degenerative changes. Both the proximal tibial and distal femoral physes were widely patent with no angular deformity. The patient had a 1-cm leg length discrepancy, with the operative limb being longer. This technical note with a case report describes a novel physeal-sparing reconstruction of the PCL in a pediatric patient with open physes.  相似文献   
129.
130.
Endoplasmic reticulum (ER) stress response is important for protein maturation in the ER. Some murine models for bone diseases have provided significant insight into the possibility that pathogenesis of osteoporosis is related to ER stress response of osteoblasts. We examined a possible correlation between osteoporosis and ER stress response. Bone specimens from 8 osteoporosis patients and 8 disease-controls were used for immunohistochemical analysis. We found that ER molecular chaperones, such as BiP (immunoglobulin heavy-chain binding protein) and PDI (protein-disulfide isomerase) are down-regulated in osteoblasts from osteoporosis patients. Based on this result, we hypothesized that up-regulation of ER molecular chaperones in osteoblasts could restore decreased bone formation in osteoporosis. Therefore, we investigated whether treatment of murine model for osteoporosis with BIX (BiP inducer X), selective inducer BiP, could prevent bone loss. We found that oral administration of BIX effectively improves decline in bone formation through the activation of folding and secretion of bone matrix proteins. Considering these results together, BIX may be a potential therapeutic agent for the prevention of bone loss in osteoporosis patients.  相似文献   
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