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61.
62.
Berensztein EB Baquedano MS Gonzalez CR Saraco NI Rodriguez J Ponzio R Rivarola MA Belgorosky A 《Pediatric research》2006,60(6):740-744
The expression of aromatase, estrogen receptor alpha (ERalpha) and beta (ERbeta), androgen receptor (AR), and cytochrome P-450 side chain cleavage enzyme (cP450scc) was studied in prepubertal testis. Samples were divided in three age groups (GRs): GR1, newborns (1- to 21-d-old neonates, n = 5); GR2, postnatal activation stage (1- to 7-mo-old infants, n = 6); GR3, childhood (12- to 60-mo-old boys, n = 4). Absent or very poor detection of ERalpha by immunohistochemistry in all cells and by mRNA expression was observed. Leydig cells (LCs) of GR1 and GR2 showed strong immunostaining of aromatase and cP450scc but weak staining of ERbeta and AR. Interstitial cells (ICs) and Sertoli cells (SCs) expressed ERbeta, particularly in GR1 and GR2. Strong expression of AR was found in peritubular cells (PCs). For all markers, expression in GR3 was the weakest. In germ cells (GCs), i.e. gonocytes and spermatogonia, aromatase and ERbeta were immunoexpressed strongly whereas no expression of ERalpha, AR, or cP450scc was detected. It is proposed that in newborn and infantile testis, testosterone acting on PCs might modulate infant LC differentiation, whereas the absence of AR in SCs prevents development of spermatogenesis. The role of estrogen is less clear, but it could modulate the preservation of an adequate pool of precursor LCs and GCs. 相似文献
63.
目的:建立大鼠的骨质疏松性椎体骨折模型,探讨骨折愈合程度与X射线、骨结构和力学性能的相互关系,以期能为临床治疗提供科学的指导和理论依据。方法:实验于2005-07/2006-07在解放军兰州军区总医院骨研所完成。实验动物:选择雌性SPF级8个月龄SD大鼠54只。实验分组:采用随机数字法将大鼠分为2组:骨质疏松组和对照组,每组27只。实验干预:骨质疏松组经双背侧手术切除卵巢,对照组行伪手术。术后3个月,所有动物麻醉下,采用L5椎体手术开窗刮除术区内松质骨方法建立人工椎体骨折模型。实验评估:于术后1,2,4,6,8,12周观察两组大鼠腰椎影像学、骨组织切片组织学与受累椎体力学性能。结果:54只SD大鼠全部进入结果分析。①影像学观察:术后两组X射线片示L5椎体有一骨折缺损透光区。对照组在术后6周时原透光区与周围骨质无明显差别,而骨质疏松组原透光区仍清晰可见,于8周时无明显差别。②组织学观察:两组软骨细胞在骨愈合1周时出现,形成软骨岛,但骨质疏松组软骨细胞每高倍视野数量明显少于对照组,另外,软骨细胞改建成成熟骨细胞,骨小梁形成数量,胶原纤维排列与对照组比较有显著性差异。③力学性能:在骨质愈合6~12周,L5椎体的最大载荷、弹性模量、最大应力明显低于同期对照组,差异有显著性意义(P<0.05)。结论:骨质疏松性椎体骨折SD大鼠模型,符合动物模型标准,可用于研究新骨形成与正常骨质结构关系,观察骨质疏松性椎体骨折愈合机制,并证明骨质疏松性松质骨骨折修复过程中,骨折愈合质量降低。 相似文献
64.
用Tris-丙酮酸钠液灌流离体豚鼠工作心脏,记录左室压的导管从左房灌流管插入,可使心脏有效工作时间达70min。用Tris-丙酮酸钠液加0.5%的氟碳液能使有效工作时间延长至90min。7-溴乙氧苯四氢巴马汀(7-bromoethyoxybenzene tetrahydropalmatine,EBP)及哌唑嗪0.1μmol/L对工作心脏各项指标均无显著影响。甲氧胺1μmol/L,多巴胺1μmol/L对LVP,ABF,T-CO等指标均有明显的药理作用。EBP 10μmol/L能对抗甲氧胺、多巴胺对上述指标的影响。 相似文献
65.
Nuclear magnetic resonance, real-time and A-scan ultrasonography, and computerized CO2 lasers were recently introduced for diagnosis and surgical treatment of brainstem tumors. These new technologies offer many advantages: safe but aggressive surgery on the brainstem, the possibility of performing a correct histologic diagnosis, and an exact indication for radiotherapy. Eleven tumors were operated on in our series: seven were intrinsic and four protruded out from the axis. Patients with high-grade malignant tumors died from 5 to 12 months after treatment, whereas those with pilocytic astrocytoma are still alive and leading useful lives. 相似文献
66.
Generalized malnutrition results in inhibition of tumorigenesis and tumor growth in experimental animal models. Neither the specific nutrient deficiency nor the mechanism has been definitely elucidated. We have shown previously that dietary sodium deprivation in rapidly growing rats retards protoplasmic growth. This effect was correlated to the extracellular fluid (ECF) volume expansion which is dependent on sodium accumulation. Since solid tumors are composed of a large quantity of ECF (which includes plasma volume) it was postulated that preventing the accumulation of new ECF by means of sodium restriction would influence tumor growth. The present study was designed to determine the effects of salt restriction on tumor growth and to relate these effects to ECF volume. Approximately 10(6) viable B16 melanoma cells were injected into C57BL/6 x DBA/2 F1 and C57 mice. A salt restricted diet (sodium less than 3 microeq/g) was provided ad libitum. The drinking solution was distilled water for the experimental group and 0.45% saline solution for the controls. There was a significant decrease in tumor growth rates during sodium restriction. The total body ECF volume increased when dietary sodium was supplied but did not change during salt restriction. Therefore, the only source for the ECF in the tumor mass was from nontumorous tissue. We conclude that during dietary sodium restriction solid tumor growth is retarded and can proceed only to the extent that ECF is released from cachectic body tissues. 相似文献
67.
Three children aged 17 months to 17 years developed right-sided peripheral lung abscesses. Clinical signs were fever and cough. Laboratory cultures were negative, and the patients did not respond to appropriate antibiotic coverage. Under fluoroscopic guidance, purulent material was removed from the abscesses by needle aspiration. The patients became afebrile within 24 hours; none suffered complications of bleeding or pneumothorax. Cultures of the aspirate were positive for microorganisms sensitive to the prescribed treatments. A simple aspiration technique is described and proposed as useful for selected patients when surgical drainage is recommended. There was no morbidity in our cases, and recovery from a typically prolonged course was shortened by the procedure. 相似文献
68.
69.
玻璃纤维桩在严重缺损牙齿修复中的应用 总被引:3,自引:1,他引:2
目的:在自行研制了弹性模量介于牙釉质和牙本质之间的玻璃纤维增强树脂桩的基础上,追踪观察其在严重缺损牙齿修复中的效果。方法:选择2005-08/2006-10在桂林医学院附属医院行桩核冠修复并能配合修复后半年复查的患者69例,用自行研制的直径分别为1.4,1.8,2.1mm的圆柱形玻璃纤维/树脂复合材料桩钉对84个严重缺损牙进行桩核冠修复,其中52个前牙,32个后牙;桩修复体直径为2.1mm者22个,1.8mm者39个,1.4mm者23个。半年后进行临床和X射线复查,桩完好、根完好、核完好及冠未脱落或松动者为纤维桩修复成功;同时观察有无材料宿主反应。结果:84个桩核冠修复体复查有2个桩和1个核松动、脱落,修复成功率为96.4%;前后牙及不同直径桩修复成功率的对比差异无显著性意义(P>0.05);所有利用纤维桩修复缺损患牙的患者均未发现有材料宿主反应。结论:玻璃纤维增强树脂桩的力学性能达到修复要求,桩可通用于各牙位,直径1.4,1.8和2.1mm等3种规格的桩都适用于临床修复。初步证明玻璃纤维增强树脂桩是一种有价值的修复方式,但还需进行更长期和更大样本的临床观察。 相似文献
70.
目的:观察人脂肪组织间充质干细胞体外分离培养及成脂、成软骨诱导分化的生物学性状,探讨其作为软骨组织工程种子细胞的可行性。方法:实验于2006-08/2007-03在吉林大学中日联谊医院前列腺疾病防治研究中心完成主要工作。实验方法:①人脂肪组织来源于健康成年女性腹部吸脂术,酶消化法分离出脂肪间充质干细胞,接种于含体积分数为0.10胎牛血清的高糖DMEM培养基进行原代培养。②取第3代脂肪间充质干细胞,采用细胞计数法测定细胞生长曲线,流式细胞仪测定CD13、CD34抗原的表达,免疫荧光法测定CD34抗原的表达。③取第3代脂肪间充质干细胞,用含体积分数为0.10胎牛血清、0.5mmol/LIBMX、1μmol/L地塞米松、10μmol/L胰岛素的成脂诱导培养基和含体积分数为0.01胎牛血清、10μg/L转化生长因子β1、50nmol/L抗坏血酸、6.25mg/L胰岛素的成软骨诱导培养基分别诱导分化。④每天用倒置显微镜观察细胞形态及增殖变化,油红"O"、AB-PSA染色和Ⅱ型胶原免疫细胞化学染色检测成脂、成软骨分化情况。结果:①体外培养的脂肪间充质干细胞呈扁平的长梭形,细胞形态均一,传代稳定。间质细胞相关标志CD13和干细胞相关标志CD34表达阳性。②定向诱导后表现出脂肪细胞和软骨细胞特性。经成脂诱导,细胞内出现空泡,油红"O"染色呈红色;经成软骨染色,AB-PSA染色呈紫红色,Ⅱ型胶原免疫细胞化学染色胞浆呈棕黄色。结论:脂肪干细胞能向软骨细胞方向诱导分化,可作为软骨组织工程种子细胞。 相似文献