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S. L. Lim  MB  BS  MMed    D. H. B. Tay  MB  BS  MMed  FAMS    E. Thomas  MB  BS  MMed  FANZCA  FAMS   《Anaesthesia》1994,49(3):255-257
  相似文献   
53.
We describe a case of preeclampsia with the HELLP (Haemolysis, Elevated Liver enzymes, Low Platelets) syndrome and highlight the delayed diagnosis due to its nonspecific presentation. This syndrome is associated with significant maternal and perinatal mortality and morbidity and we discuss the importance of early recognition of the condition, aggressive management and a multidisciplinary approach.  相似文献   
54.
硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
55.
4 cases of syringomyelia with type I Arnold Chiari malformation was seen presenting mainly with dissociated sensory loss, weakness of hands and upper motor neurone signs in the lower limbs. The first patient improved with posterior fossa decompression. The second and fourth patient appeared not to have improved after surgery, and the third case refused operation. One patient showed cord atrophy on myelogram presumably due to a collapse of the syrinx. One of the patients was unusual in that the syrinx extended down to segment T11. Magnetic resonance imaging of the posterior fossa and the cervical cord, to date, is the most useful procedure for diagnosis.  相似文献   
56.
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。  相似文献   
57.
BACKGROUND CONTEXT: In patients with spinal osteoporosis, the early achievement and maintenance of a biological bond between the pedicle screw and bone is important to avoid screw loosening complications. There are few reports of in vivo investigations involving biomechanical and histological evaluations in the osteoporotic spine. PURPOSE: To evaluate the effect of hydroxyapatite (HA)-coating on the pedicle screw in the osteoporotic lumbar spine and to investigate the relationship between resistance against the screw pull-out force and bone mineral density (BMD) of the vertebral body. STUDY DESIGN/SETTING: Mechanical and pathological investigations in the lumbar spine. METHODS: Two 24-month-old female beagle dogs were fed a calcium-free dog chow for 6 months after ovariectomy (OVX). BMD (in g/cm2) was measured by dual energy X-ray absorptiometry at pre-OVX and 6 months after OVX. Pedicle screws were placed from L1 to L6 at 6 months after OVX. Twenty-four pure titanium cortical screws (Synthes, #401-114) were used as pedicle screws (Ti-PS). Of these, 12 screws had HA-coating (HA-PS). The HA-PS screws were inserted into the right pedicles and the Ti-PS were inserted into the left pedicles. Ten days after this procedure, the lumbar spines were removed en bloc for screw pull-out testing and histological evaluation. RESULTS: The mean BMD value of the lumbar vertebrae 6 months after the OVX was 0.549+/-0.087 g/cm2, which was significantly less than the pre-OVX mean BMD of 0.603+/-0.092 g/cm2 (p < 0.001). The mean resistance against the pull-out force for the HA-PS was significantly greater at 165.6+/-26.5N than in the Ti-PS (103.1+/-30.2N, p < .001). The histological sections in the HA-PS clearly revealed new bone bonding with the apatite coating but only fibrous tissue bonding in the Ti-PS. CONCLUSIONS: The results of this study showed that the resistance to the pull-out force of HA-PS is 1.6 times that of Ti-PS. Furthermore, HA-PS has superior biological bonding to the surrounding bone, as early as 10 days after surgery in this osteoporotic spine model. Thus, in patients with osteoporosis, coating of the pedicle screw with HA may provide better stability and bonding between the pedicle screw and bone in the early postoperative period.  相似文献   
58.
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas.  相似文献   
59.
Okadaic acid (OA) and 12-O-tetradecanoylphorbol-13-acetate (TPA)are both potent tumor promoters in a mouse skin carcinogenesisexperiment. OA was much more toxic than TPA for murine embryocell lines such as Swiss 3T3 cells or C3H10T? cells. TPA isa potent mitogen for 3T3 cells; in contrast OA was unable tostimulate DNA synthesis in these cells. TPA induces a familyof primary response genes, the TPA induced sequence (TIS) genes,in a wide variety of cells. Although OA induced modest levelsof TIS mRNA expression, the time course of the induction ofTIS1 and TIS8 mRNA was delayed when compared to induction byTPA or peptide mitogeas such as fibroblast growth factor (FGF).In addition TPA-mediated down-regulation of protein kinase Cattenuated TIS gene induction by OA, but not by FGF.  相似文献   
60.
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