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991.
目的探讨精索脂肪肉瘤的临床特点和诊治方法。方法回顾6例精索脂肪肉瘤临床资料,并复习有关文献。结果6例患者均行手术治疗,2例行肿瘤切除术,其余4例行根治术,术后随访19个月-11年,1例保留精索的年轻患者于术后3年出现局部复发,其余5例无复发及远处转移。结论精索脂肪肉瘤是一种低度恶性肿瘤,治疗方法主要以根治性手术为主,对于肿瘤高分化且年轻未育者,可行保留精索手术。  相似文献   
992.
993.
目的 探讨在少、弱精子症中精子形态缺陷类型及其发生率.方法 对精液常规和改良巴氏染色检查的结果进行统计学分析.结果 (1)男性不育症中畸形精子症的发生率约为75%;精子头部缺陷的发生率约为70%,各种头部缺陷中空泡头畸形的发生率占首位,约为20%.(2)少精子症患者的正常形态精子百分率的中位数约为2.97%(P=0),弱精子症患者的中位数为6.67%(P=0.003).结论 (1)精子头部缺陷是精子畸形的主要类型;(2)少、弱精子症的畸形精子比例升高;(3)精子形态缺陷分析对选择辅助助孕方式具有应用价值.  相似文献   
994.
目的研究鼠婴肾组织移植于肾包膜下对促红细胞生成素的调节作用,为临床应用治疗肾性贫血提供理论依据。方法以Wistar雄性大鼠建立慢性肾功能衰竭动物模型为受体,将鼠婴肾组织块多点植入受体肾包膜下。治疗期间用EPO酶联免疫(ELISA)试剂盒测定血清EPO水平;观察肾组织病理改变,用免疫组化方法检测EPO在移植物中的表达。结果①60d时D组血清促红细胞生成素(1.768±0.140)mu/mL高于B组(1.160±0.324)mu/mL(P<0.01),与C组(2.329±0.125)mu/mL也有差异(P<0.05)。②移植后60d,移植物的体积由1mm3增至3-4mm3大小,表面血管网丰富,光镜下见肾小球、肾小管结构正常;③移植物EPO免疫组化,发现移植物EPO着色颗粒主要分布于肾皮质的肾小管,明显多于病例对照组大鼠肾组织(P<0.05)。结论通过对移植物的形态观察和功能测定,证明肾组织移植是一种有效的治疗手段,有可能为慢性肾性贫血提供一种新的途径。  相似文献   
995.
BACKGROUND AND PURPOSE: Helicobacter pylori infection is primarily acquired in early childhood and its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G (IgG) in Taiwanese and to investigate whether a common mode of transmission could be shared between H. pylori and hepatitis A virus (HAV). METHODS: An enzyme-linked immunosorbent assay (ELISA) was used to investigate the prevalence of H. pylori among 924 healthy volunteers aged less than 40 years, and radioimmunoassay for HAV infection was conducted in 500 subjects from the same population. The kappa statistic was used to measure the difference in positivity for the 2 infections in a subgroup of 500 subjects who had their sera simultaneously tested for anti-H. pylori and anti-HAV antibodies. RESULTS: The seroprevalence of anti-H. pylori IgG was 16.7% in subjects aged < 16 years and 38.3% at ages >or= 16 years. Most children (99%) under the age of 16 were seronegative for HAV. The prevalence of H. pylori infection increased rapidly with age, at 1%/year and 0.8%/year for children and adults, respectively. The rate of H. pylori infection was higher in male (21%) than in female (12%) children (p < 0.01; OR, 2.0; 95% confidence interval, 1.2 to 3.0). No significant difference in seroprevalence between genders was noted in subjects aged >or= 16 years. The agreement in the trend of seropositivity between both infections in the age groups 1 to 10 years and 10 to 20 years was worse than chance (kappa = -0.56) and little better than chance (kappa = 0.01), respectively. CONCLUSIONS: Acquisition of H. pylori infection occurs at a young age, and male children are more likely to develop the infection. The main transmission route of HAV, the fecal-oral route, did not seem to be responsible for H. pylori transmission in this Taiwanese cohort.  相似文献   
996.
采用液相色谱/质谱(LC/MS)方法检测糖皮质激素、甾体和β2激动剂。本文采用Zorbax 30 mm×2.1mm,1.8μm短柱,对12种糖皮质激素、3种甾体和2种β2激动剂的液相色谱/质谱的测定方法进行了研究,建立了6分钟内快速检测人尿中多种糖皮质激素、甾体和β2激动剂的测定方法。检测限低于5ng/ml。该方法适用于兴奋剂的筛选及确证。  相似文献   
997.
目的探讨烟雾病的临床特征及影像学表现,以提高对本病的诊断率。方法对20例烟雾病患者的临床特征和影像学资料进行回顾性分析。结果临床表现:发病年龄为10~19岁占50%(10/20),40岁以前占90%(18/20),缺血型患者主要为偏瘫、失语,出血型患者主要为头痛、呕吐、意识障碍和偏瘫,20例中反复TIA发作者7例,其中两侧交替发作者2例;CT/MRI:脑梗死6例,脑出血13例(脑室出血4例,再出血3例);梗死或出血病灶发生在基底节6例,脑叶9例,多发性病灶6例,梗死并出血5例;DSA示颈内动脉、大脑前、中动脉狭窄或闭塞,脑基底部烟雾状血管网形成,大脑后动脉(PCA)及其分支增粗者16例,颈外动脉系统向颅内代偿8例。结论对于儿童、青年人出现中风、反复交替性TIA发作、CT/MRI呈多发性脑梗死或出血、脑叶梗死或出血、脑室出血及再出血患者应高度考虑烟雾病,应行DSA检查;DSA可清晰显示烟雾病血管狭窄的程度、闭塞部位及侧支循环的情况。  相似文献   
998.
The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions.  相似文献   
999.
目的通过分析颈动脉粥样硬化与冠心病的关系探讨颈动脉超声对诊断冠心病的临床意义。方法将120例入选对象分为对照组,稳定性心绞痛(SA)组,不稳定性心绞痛(UA)组,急性心肌梗死(AMI)组,每组30例,分别给予超声检测颈动脉内-中膜厚度(IMT),同时测定3组冠脉造影结果:正常组21例,单支病变组18例,多支病变组29例。结果冠心病患者IMT较正常对照组有显著增厚(P<0.01),且冠脉造影正常组与单支、多支病变组间亦存在显著性差异(P<0.05)。结论颈动脉超声检测对冠心病的预测具有确切的临床意义。  相似文献   
1000.
BACKGROUND AND PURPOSE: Gastrointestinal stromal tumors (GISTs), identified by the presence of CD117 (KIT), were previously classified as gastric and intestinal smooth muscle tumors prior to the availability of immunohistochemical methods. This study evaluated the percentage of GISTs previously diagnosed as gastric smooth muscle tumors in our hospital during an 11-year period. METHODS: A total of 81 surgically resected gastric smooth muscle tumor specimens from 81 patients were collected from January 1986 to December 1997. Immunohistochemical studies were performed on these tumors with antibodies of CD34, CD117, smooth muscle actin (SMA), S-100, and desmin. RESULTS: Among the 81 tumors, 74 (91.4%) were CD117-positive and were classified as GISTs. Among the 74 GISTs, CD34 was positive in 72 tumors (97.3%), SMA was positive in 12 tumors (16.2%), desmin was positive in 5 tumors (6.7%), and S-100 was positive in 4 tumors (5.4%). The 7 tumors classified as non-GISTs had the following immunohistochemical characteristics: 1 was a CD117-negative CD34-positive stromal tumor (GINST) [1/81, 1.2%]; 3 were schwannomas with strong S-100-positive characteristics (3/81, 3.7%); and 3 were smooth muscle tumors with both SMA- and desmin-positive status (3/81, 3.7%). No clear relationship between CD117 or CD34 expression and prognosis was found for these tumors. CONCLUSIONS: The majority (91.4%) of gastric tumors originally diagnosed as gastric smooth muscle tumors were GISTs, except for small groups of smooth muscle tumors and schwannomas.  相似文献   
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