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91.
92.
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   
93.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
94.
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.  相似文献   
95.
BACKGROUND: Recently, epidemiological and clinical data have revealed important changes with regard to clinical adenovirus infection, including alterations in antigenic presentation, geographical distribution, and virulence of the virus. METHODS: In an effort to better understand the epidemiology of clinical adenovirus infection in the United States, we adopted a new molecular adenovirus typing technique to study clinical adenovirus isolates collected from 22 medical facilities over a 25-month period during 2004-2006. A hexon gene sequence typing method was used to characterize 2237 clinical adenovirus-positive specimens, comparing their sequences with those of the 51 currently recognized prototype human adenovirus strains. In a blinded comparison, this method performed well and was much faster than the classic serologic typing method. RESULTS: Among civilians, the most prevalent adenovirus types were types 3 (prevalence, 34.6%), 2 (24.3%), 1 (17.7%), and 5 (5.3%). Among military trainees, the most prevalent types were types 4 (prevalence, 92.8%), 3 (2.6%), and 21 (2.4%). CONCLUSIONS: For both populations, we observed a statistically significant increasing trend of adenovirus type 21 detection over time. Among adenovirus isolates recovered from specimens from civilians, 50% were associated with hospitalization, 19.6% with a chronic disease condition, 11% with a bone marrow or solid organ transplantation, 7.4% with intensive care unit stay, and 4.2% with a cancer diagnosis. Multivariable risk factor modeling for adenovirus disease severity found that age <7 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4-7.4), chronic disease (OR, 3.6; 95% CI, 2.6-5.1), recent transplantation (OR, 2.7; 95% CI, 1.3-5.2), and adenovirus type 5 (OR, 2.7; 95% CI, 1.5-4.7) or type 21 infection (OR, 7.6; 95% CI, 2.6-22.3) increased the risk of severe disease.  相似文献   
96.
TUVP手术时间对血红蛋白及电解质的影响   总被引:2,自引:0,他引:2  
目的 了解经尿道前列腺汽化电切手术时间对血红蛋白及血清电解质的影响。方法 对64例经尿道前列腺汽化电切术患按手术时间分组,观察手术前后血红蛋白及血清电解质的变化。结果 手术时间对血清电解质的降低有的影响,对血红蛋白降低的影响不显。结论 减少TUR综合征的关键是要操作熟练,缩短手术时间及手术中注意止血。  相似文献   
97.
98.
Background: Research on religion and health suggests general health benefits for those who are more religiously involved. Particular aspects of religiosity that may influence this finding, however, have not been sufficiently investigated.Purpose: This study was designed to explore the relationship between religious orientation (intrinsic, extrinsic) and blood pressure reactivity among older (over 60 years) and younger (18–24 years) adults exposed to two qualitatively different laboratory stressors (cognitive, interpersonal).Methods:Participants were categorized as exhibiting either a predominately intrinsic or extrinsic religious orientation based on scores on the Religious Orientation Scale. They were subsequently exposed (in counterbalanced order) to two laboratory stressors that varied in terms of whether an interpersonal confrontation was involved. Measures of blood pressure were obtained at baseline and during stressor presentation.Results: Analyses indicated that older extrinsically religious individuals demonstrated exaggerated reactivity compared to younger participants and older intrinsically religious individuals. Older intrinsically religious participants did not differ from younger persons. Similar results were found for analysis of baseline data. Extrinsic participants had greater reactivity during the interpersonal confrontation condition than did intrinsic individuals.Conclusions: These findings suggest that religious orientation may be an important variable to study regarding cardiovascular reactivity in, particularly, older adults. This research was supported in part by National Institute on Aging Grant 1 R03 AG 18554-01. A previous version of this article was presented in August 2002 as a Citation Paper at the 110th Annual Convention of the American Psychological Association, Chicago. We thank Timothy W. Smith, James A. Blumenthal, Carl E. Thoresen, and Edward M. Heath for their assistance throughout this project. We also thank Llewellyn Jones and Jodi Hildabrandt for their efforts in collecting data.  相似文献   
99.
100.
多系统萎缩的临床分型和影像学改变特点分析   总被引:2,自引:0,他引:2  
目的探讨多系统萎缩(multiple system atrophy,MSA)的临床表现类型与神经影像学改变新特征(脑桥“十字征”和“壳核裂隙征”)的关系,为临床尽早做出诊断提供依据。方法按照Gilman诊断标准回顾性分析11例MSA患者的临床表现、分型和头颅MRI资料。结果本组诊断为很可能MSA11例,其中橄榄体脑桥小脑萎缩(MSA-C型)8例。2例在发病后3年头颅MRI脑桥“十字征”达Ⅰ期;1例在病后2年达Ⅱ期;3例分别在病后1年、3年、5年达Ⅲ期;另外2例分别在病后2年和7年达Ⅳ期。8例“壳核裂隙征”均为0期。黑质纹状体变性(MSA-P型)2例:1例病后6年脑桥“十字征”0期,“壳核裂隙征”Ⅰ期,另1例发病后9年“壳核裂隙征”Ⅱ期,脑桥“十字征”Ⅳ期。Shy-Drager综合征(MSA-A型)1例:病程5年,MRI检查脑桥“十字征”和“壳核裂隙征”分期均为0期。结论临床表现与头颅MRI检查发现的脑桥“十字征”和“壳核裂隙征”可作为及早识别MSA-C型的神经影像学改变特征,“壳核裂隙征”可作为识别MSA-P型的神经影像学改变特征。  相似文献   
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