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11.
采用DNA聚合酶链反应-单链构象多态性分析和直接序列测定技术,检测25例肾细胞癌组织中P53基因5-8外显子,25例肾细胞癌仅有2例肿瘤组织存在P53基因点突变,分别位于154和273密码子上,核苷酸序理分析突变形式分别为G→T,C→T。结果提示:肾细胞癌组织中P53基因突变并不显著,表明肾细胞癌的发生可能是一个多基因变化的过程。  相似文献   
12.
大鼠肝细胞Ⅰ,Ⅲ型前胶原基因表达及PDGF的影响   总被引:3,自引:1,他引:2  
目的观察大鼠肝细胞Ⅰ,Ⅲ型前胶原基因的表达及PDGF对其表达的影响.方法应用原位杂交技术检测分离培养的SD大鼠肝细胞(n=30)内Ⅰ,Ⅲ型前胶原基因的表达.同时观察10μg/L(n=30)和30μg/L(n=30)PDGF促进前胶原基因表达的作用.测定基因表达颗粒总面积占细胞总面积的百分比,并作比较分析.结果无论正常肝细胞或是在两种浓度的PDGF存在时,肝细胞内均可见到Ⅰ,Ⅲ型前胶原基因的表达.正常肝细胞Ⅰ,Ⅲ型前胶原基因表达面积的百分比(%)为77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成.  相似文献   
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14.
本文采用RP-HPLC方法对紫苏油及其习用品白苏油、野苏油甘油酯进行了定性定量分析。利用HPLC分析油脂也为中药材真伪鉴别提供了一条有效途径。  相似文献   
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16.
Genetic susceptibility of esophageal cancer in Linxian County   总被引:3,自引:0,他引:3  
  相似文献   
17.
目的 总结32例前列腺癌患者新辅助治疗(NHT)的作用。方法 32例前列腺癌患者中药物去势17例,手术去势15例,并联合抗雄激素治疗3个月,统计NHT前后前列腺癌体积、肿瘤大小、PSA、FSH、LH和睾酮水平变化。结果 2组NHT后前列腺体积明显变小、肿瘤变小、变软,甚至消失,PSA和睾酮明显下降,药物去势组睾酮水平在耻骨后前列腺癌根治术(RRP)术后2~3个月可恢复正常,而手术去势组RRP术后睾酮呈持续低水平。结论 NHT可明显缩小前列腺体积,降低PSA,有利于手术操作。药物去势对内分泌影响是可逆的,而手术去势内分泌改变不可逆。  相似文献   
18.
Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3 x 5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process.  相似文献   
19.
BACKGROUND/PURPOSE: Abdominal nontuberculous mycobacterial infection is a rare condition. Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis is the most common manifestation of infection due to nontuberculous mycobacteria (NTM). There are limited data on the clinical manifestations of nontuberculous mycobacterial infection. This study investigated the diagnostic features, clinical presentation, mycobacteriology, treatment and outcome of all abdominal NTM infections treated over a 7-year period at a major teaching hospital in Taiwan. METHODS: The medical records of all patients with a diagnosis of abdominal NTM infection from January 1997 through to December 2003 were retrospectively reviewed. RESULTS: All 11 patients with abdominal NTM infections identified during the 7-year period were included. Among these patients, six were male and five were female, with a mean age of 64.5 years. The disease manifested as peritonitis (9 patients, 82%), splenic abscess (1, 9%), or perirenal abscess (1, 9%). Most patients (73%) had underlying malignancy, most often hepatoma (45%). Immunocompromised status (liver cirrhosis, malignancy, acquired immunodeficiency syndrome) was noted in 10 patients (91%). None of our patients who developed NTM peritonitis had received CAPD. The peritoneal fluid appearance varied considerably, with no particular predominance of clear, turbid, bloody, or chylous findings. Rapidly growing mycobacteria were the major etiology (46%) of abdominal NTM infection, and Mycobacterium abscessus played a major role (27%). Overall, eight patients died, and only one patient survived longer than 1 year. Seven patients (64%) died before diagnosis. CONCLUSION: Abdominal NTM infection is frequently overlooked because of its rarity and nonspecific symptoms, with consequent delays in diagnosis and treatment. In immunocompromised patients with ascites from any cause (liver cirrhosis, malignant ascites, etc.), NTM peritonitis should be considered early in the differential diagnosis of symptoms including fever, abdominal pain and weight loss. The poor prognosis of abdominal NTM infection appears to be related to the severity of underlying conditions, most often malignancy.  相似文献   
20.
BACKGROUND: In recent years some reports have been published propagating microsurgical resection of ventral foramen magnum meningiomas (VFMMs). Operative approaches to these lesions have been studied by various authors, but remain controversial. OBJECTIVE: To discuss the operative technique and outcome in patients with VFMMs who had been treated via a far lateral suboccipital approach. DESIGN: Retrospectively clinic case investigation. SETTING: Department of Neurosurgery, the Ninth People's Hospital, Medical School of Shanghai Jiao Tong University. PARTICIPANTS: Between January 1997 and June 2003, 10 patients were treated surgically with VFMMs in Department of Neurosurgery, the Ninth People's Hospital, Medical School of Shanghai Jiao Tong University. In the series of 10 patients, ages ranged from 37 to 72 years, mean (53±10) years, were consisted of 6 males and 4 females. All the subjects were informed of the treatment plan and agreed to join the experiment. Early symptoms included headache and upper cervical pain. The time between the first occurrence of symptoms and the diagnosis ranged from 6 months to 17 months, mean (10.3±3.4) months. Main presenting symptoms were unilateral upper extremity sensory and motor deficits in 6 cases, swallowing difficulties in 2 and spastic quadriparesis in 2. VFMMs were demonstrated as round by the computed tomographic (CT) scan and magnetic resonance imaging (MRI) in all patients. The maximum diameter of tumors ranged from 2 to 4 cm, mean (2.55±0.57) cm, including 2 cm in one case, 2.0-3.0 cm in six and 3.0-4.0 cm in three. METHODS: ①All tumors were removed via the far lateral suboccipital approach. Resection of the posterior 5 mm of the condyle was necessary in one patient whose tumors' diameter were 2 cm. The patient was situated in the lateral decubitus position. The head was fixed in a Mayfield headrest. A C-shaped incision made behind the ear 2 cm medial to the mastoid process, turning vertically down to the level C4, to expose the extradural segment of the vertebral artery (VA). After the dura was opened longitudinally behind VA entry point, the tumor was revealed to identify the complete cranial nerves and the intracranial VA under magnification of the surgical microscope. Every attempt should be made to keep the arachnoid and the dentate ligament was sectioned. Then the tumor was debulked significantly, and dissected away from the cranial nerves and the blood vessels with microsurgical techniques. If it was risk to dissect tumor from the vertebral artery, its branches, or any cranial nerve, the progression was discontinued and portion of the tumor was left behind. After resection of the tumor, the site of its attachment was coagulated and the involved layer of dura was resected. ②The degree of tumor resection was classified based on Al-Mefty's grade into three categories: gross-total resection: excision of the dural attachment and drilling of adjacent bone; near-total resection: a few millimeters of insulated and cauterized tumor were left on the vertebral artery or other vital; subtotal resection: more than 50% of the tumor mass were removed. ③All patients underwent clinical examination for lower cranial nerves or long tract deficits on the first day postoperatively. CT or MRI and neurological examinations were performed at 3 months of follow-up. MAIN OUTCOME MEASURES: Operative effect. RESULTS: All ten patients with VFMMs were treated via a far lateral suboccipital approach. Gross total resection was achieved in 6 patients, near-total resection was carried out in 2 and subtotal resection in 2 patients. One patients died in the postoperative period due to acute respiratory distress syndrome, five patients kept normal neurological status, whereas other four patients suffered from lower cranial nerve deficits and aspiration pneumonia was observed in two of them. The data of following up for 3 months showed that 2 patients still had lower cranial nerve deficit and others recovered from their illness. No tumor relapse or increment was found in CT or MRI scans. CONCLUSION: Most of VFMMs could be totally removed via a far lateral suboccipital approach with or without resection of the occipital condyle according to the tumor size, allowing most of these patients to achieve a good outcome in a 3 months follow-up.  相似文献   
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