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71.
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   
72.
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   
73.
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   
74.
目的 分析脑出血患者血清瘦素浓度的变化,探讨瘦素与脑出血的关联。方法 对86例脑出血患者和58例对照者进行瘦素、空腹胰岛素等的检测,并进行比较。结果 (1)脑出血组与对照组相比胰岛素敏感指数(ISI)降低(P〈0.01),男性患者瘦素水平高于对照组(P〈0.01)。(2)脑出血组与对照组相比收缩压和舒张压水平均升高(P〈0.01)。(3)脑出血患者血清瘦素水平与ISI呈负相关(P〈0.05)。(4)男性患者中高瘦素-高血压水平(收缩压或舒张压)的联合作用与增加脑出血的危险强烈相关。结论 脑出血患者存在胰岛素抵抗;男性脑出血患者的瘦素水平升高,高瘦素-高血压水平的联合作用增加发生脑出血的危险。  相似文献   
75.
SUMMARY: It is desirable to estimate epileptogenic zones with both location and extent information from noninvasive EEG. In the present study, the authors use a subspace source localization method (FINE), combined with a local thresholding technique, to achieve such tasks. The performance of this method was evaluated in interictal spikes from three pediatric patients with medically intractable partial epilepsy. The thresholded subspace correlation, which is obtained from FINE scanning, is a favorable marker, which implies the extents of current sources associated with epileptic activities. The findings were validated by comparing the results with invasive electrocorticographic (ECoG) recordings of interictal spike activity. The surgical resections in these three patients correlated well with the epileptogenic zones identified from both EEG sources and ECoG potential distributions. The value of the proposed noninvasive technique for estimating epileptiform activity was supported by satisfactory surgery outcomes.  相似文献   
76.
目的探讨经尿道等离子双极电切术(PKRP)治疗良性前列腺增生(BPH)术后对阴茎勃起功能的影响。方法PKRP、经尿道前列腺电切术(TURP)治疗BPH各95例,评价其术后1个月、3个月及1年阴茎勃起功能。结果PKRP、TURP术后1个月、3个月及1年阴茎勃起功能障碍(ED)发生率分别是3.2%、2.1%、2.1%和13.7%、10.5%、9.5%。结论PKRP术后ED发生率比TURP低,是一种对阴茎勃起功能较为安全的治疗良性前列腺增生的方法。  相似文献   
77.
脑血管意外尿失禁的机制探讨   总被引:4,自引:0,他引:4  
目的探讨脑血管意外引起尿失禁的可能机制。方法对42例诊断为脑血管意外伴有尿失禁的患者进行尿动力学检查(包括静止期尿道压测定、充盈期及排尿期膀胱尿道功能测定)并按Burney分类进行分析,同时研究病变部位、脑血管意外性质和病变半球侧与尿动力学的关系。结果42例脑血管意外患者中,表现为逼尿肌反射亢进者31例(73.8%):其中外括约肌无抑制性松弛19例(45.2%),逼尿肌-外括约肌不协调3例(7.1%),逼尿肌-外括约肌协调9例(21.4%);逼尿肌反射减低,外括约肌协调者11例(26.2%);无逼尿肌功能正常者。发生膀胱顺应性减低5例(11.9%),发生尿感缺失者11例(26.2%)。初感尿容量(140.00±46.97)ml;膀胱最大容量(293.20±60.71)ml;最大尿道闭合压(65.14±19.83)cmH2O。逼尿肌最大收缩力(Pdetmax)为(60.98±31.11)cmH2O;最大尿流率时逼尿肌压力(Pdet-Qmax)为(35.98±17.46)cmH2O;逼尿肌收缩时间(Tcon)为(86.07±36.09)sec;最大流量(Qmax)为(9.02±5.62)ml/s。中风后尿失禁患者其发病部位多见于基底节、皮层多灶以及额顶叶,脑出血与脑梗塞患者的尿动力学表现无明显差异,左右半球病变对尿动力学也无明显差异。结论脑血管意外后尿失禁的尿动力学异常主要为逼尿肌反射亢进,部分出现逼尿肌反射减弱,但感觉正常,感觉缺失者较少见;外括约肌功能以无抑制性松弛为主,其次为逼尿肌-外括约肌协调,少数出现不协调;较少出现膀胱顺应性降低。  相似文献   
78.
膀胱癌中环氧化酶-2的表达与临床病理的关系(英文)   总被引:4,自引:2,他引:2  
目的 探讨环氧化酶 - 2 (COX - 2 )表达与膀胱癌生物学行为的关系及其意义。方法 采用免疫组化SABC法检测 5 4例膀胱癌、2 9例癌旁组织和 10例正常膀胱粘膜中的COX - 2表达 ,结合临床病理资料进行分析。结果 COX - 2在不同膀胱组织中的表达差异有显著性 (P <0 .0 5 ) ,即膀胱癌组织 >癌旁组织 >正常膀胱粘膜。COX - 2表达随膀胱癌病理级和临床分期的增加而增加 (P <0 .0 5、P <0 .0 1) ,且癌组织中COX - 2表达与淋巴转移有关 (P <0 .0 5 )。结论 COX - 2表达与膀胱癌病理分级、临床分期、淋巴转移有关 ,提示它可能在胱癌的发生、发展中扮演重要角色 ,通过抑制COX - 2活性可能为膀胱癌的防治提供新途径。  相似文献   
79.
研究了双波长技术在干扰物槲皮素存在下测定芦丁含量的方法,槲皮素浓度大到20mg/L时,误差不超过0.4%,回收率为94.2%~100.2%。  相似文献   
80.
本文对20岁以上22830人按HBsAg状况和肝损害表现分队列进行随访,平均追踪6.8年,在肝癌高发区和低发区均以HBsAg携带者并有重度肝损害者(肝大+肝功能异常)的肝癌死亡率和相对危险性最高,相对危险性分别为37.3和22.5倍。以无肝大和肝功能异常的非携带者最低,肝癌的发生和肝损害的程度呈平行关系。HBsAg携带者发生肝癌死亡的相对危险性高于非携带者7倍,并发现HBsAg携带并有重度肝损害的肝癌死亡的平均年龄显著提前。认为肝癌高发区人群中HBV的持续感染和肝损害的广泛存在是导致肝癌高发和早发的重要因素。  相似文献   
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