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41.
Hyo-Chang Kim Seok-Gu Kang Pil-Woo Huh Do Sung Yoo Kyoung Suok Cho Dal Soo Kim 《Journal of clinical neuroscience》2007,14(11):1135-1139
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition. 相似文献
42.
43.
Transforminggrowthfactor-β1(TGF-β1)is amultifunctionalpolypeptidethatregulatesanum-berofcellularprocesses,includingcellprolifera-tion,differentiation,apoptosis,migration,matrix synthesis,andtheimmuneresponse[1,2].Inchron-icrenaldiseases,TGF-β1isakeymediatorofex-tracellularmatrix(ECM)accumulation[3].Oneof thetargetrenalcellsforTGF-β1isglomerular mesangialcellsthatarecapableofproducingcom-ponentsofECM,suchascollagens,lamininand fibronectin[4,5].Recentstudiesindicatedthatinhi-bitionofT… 相似文献
44.
双头加压螺纹钉贴股骨距内固定治疗股骨颈骨折 总被引:8,自引:0,他引:8
在X光电视下采用双头加压螺纹钉贴股骨距内固定治疗新鲜股骨颈骨折42例,随访平均2.5年,其中16例随访3年以上,骨折愈合率95.2%,骨折不愈合并股骨头缺血性坏死率4.76%。认为加压螺纹钉贴股骨距内固定可使钉的受力由较大剪应力变为较大轴向力承受,减少骨折处的剪应力,并加压于骨折端能促进骨折愈合。具有操作简单、进钉准确、创伤小、固定牢靠、并发症少等优点。 相似文献
45.
R T Pham M Sung C R Dawson J Schachter 《Investigative ophthalmology & visual science》1990,31(7):1367-1373
The development and testing of candidate vaccines for trachoma are constrained because only humans and nonhuman primates are susceptible to conjunctival infection with Chlamydia trachomatis. Guinea pig inclusion conjunctivitis (GPIC), an analogous disease of guinea pigs, provides a useful, less expensive model to study ocular chlamydial infections. GPIC is caused by a Chlamydia psittaci strain whose external constituents are very similar to those of C. trachomatis. To develop a better model for studying GPIC immunity, conjunctival pockets were established under the abdominal skin of guinea pigs by subcutaneous implantation. Up to six implants could be produced in each animal. The success rate of implantation was 79.0% (n = 148). These pockets were then infected with GPIC. The organism was recovered from the autografts indicating local replication, and tests for serum antibody by microimmunofluorescence showed production of GPIC-specific antibody of IgG and IgM classes after infection. There was minimal antibody response after moderate inoculating doses to the implants, and the titers increased more slowly than after eye infection with GPIC; with higher concentration of the inoculum, however, the antibody response increased to the same levels as with the ocular challenge but more slowly. Inoculation of pockets with GPIC also produced acute inflammatory changes in infected autografts (n = 101). Histologic examination of infected grafts showed chlamydial inclusions in epithelial cells and significant infiltration with lymphocytes and polymorphonuclear cells. Subcutaneous autografts may provide a useful model for chronologic studies of chlamydial infection. The delayed immunologic response, however, suggests that these pockets of implanted epithelium do not have full access to the immune system. 相似文献
46.
Jin Woo Kim M.D. Ho Shik Kim M.D. In Kyung Kim M.D. Mee Ran Kim M.D. Eun Young Cho B.S. Heung Kee Kim M.D. Joon Mo Lee M.D. Sung Eun Namkoong M.D. 《Gynecologic oncology》1998,69(3):230-236
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein. 相似文献
47.
扩大的椎板间开窗治疗腰椎间盘突出伴侧隐窝狭窄(附140例报告) 总被引:1,自引:0,他引:1
本组采用的扩大的椎板开窗术治疗腰椎间盘突出合并侧隐窝狭窄140例。结果全部优良,与适应症严格选择和手术损伤小有关。强调切除卡压神经根的侧隐窝后壁外侧,即上关节突的冠状面.不失其脊椎三柱系统的三角结构。俯卧位头低足高,可减少硬膜囊张力避免负损伤。切除棘突下椎板时,用神经拉勾代替神经剥离器易于分离黄韧带,用90度的椎板咬骨钳斜向棘突方向,可满意地切除该部份椎板黄韧带,并可刮切椎板内层。神经根周围滴入醋酸炎舒松A2-3ml,术后疼痛锐减。减压窗口置盖明胶海绵有其争议,作者实践体会放置害处不大,要求病人有“护腰”意识。 相似文献
48.
M. Jung E. Krämer M. Grzenkowski K. Tang W. Blakemore A. Aguzzi K. Khazaie K. Chlichlia G. von Blankenfeld H. Kettenmann J. Trotter 《The European journal of neuroscience》1995,7(6):1245-1265
Replication-defective retroviruses expressing the t- neu oncogene, or a hybrid protein with the neu tyrosine kinase linked to the external region of the human epidermal growth factor receptor ( egfr-neu ), were used to establish lines of murine oligodendroglial precursor cells. Differentiation of the t- neu lines into myelin-associated glycoprotein (MAG)-positive oligodendrocytes was induced by dibutyryl cAMP, and the egfr-neu line showed limited differentiation in vitro upon withdrawal of epidermal growth factor. Cerebellar granule cell neurons expressed mitogens for the cell lines. Upon transplantation into demyelinated lesions, t- neu line cells engaged with the demyelinated axons whereas the egfr-neu line cells differentiated further and ensheathed the axons. These cell lines thus interact with neurons in vitro and in vivo and can be used as tools to define the molecules involved in different stages of neuron-glia interaction. 相似文献
49.
真皮下血管网岛状皮瓣抗菌力的实验研究 总被引:2,自引:0,他引:2
为研究真皮下血管网薄皮瓣用于感染创面的可行性,在家猪臀部两侧分别形成以旋髂深血管主干分支为蒂的传统岛状皮瓣和远侧50%修薄的真皮下血管网岛状皮瓣。用细菌计数、吖啶橙荧光染色测定白细胞吞噬指数和白细胞内杀菌率,应用激光多普勒、墨汁灌注、透明标本等方法,对两种皮瓣的抗菌力作自身对照研究。结果表明,真皮下血管网岛状皮瓣的抗菌力明显降低,可能与皮瓣修薄后血供减少,白细胞功能相应降低有关。 相似文献
50.
本文总结了北京大学口腔医学院3届八年制口腔医学专业学生口腔固定修复学临床前期实习教学的经验,针对实习中出现的典型问题进行了分析,采取了相应的对策和方法,取得了良好的效果. 相似文献