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991.
The current report focuses on two patients of the same age who presented similar appearances on initial anteroposterior chest images. Follow-up images showed superoanterior and superoposterior mediastinal lesions. The first patient with noninvasive cystic thymoma was suspected before surgery, while the pathologic diagnosis was intrathoracic phrenic nerve schwannoma. The second patient was with an asymmetric, dumbbell-shaped paravertebral tumor over T3 and T4 on the left side. The preoperative…  相似文献   
992.
实验中发现Mn(Ⅱ)能够催化5-Br-PADAP与过氧化氢之间的氧化还原反应,并找到了Mn^2+浓度与催化褪色反应速度间的线性关系,线性浓度范围为0.5-10ng/mL,最小检出浓度为0.2ng/mL。方法灵敏度高,选择性好。  相似文献   
993.
王福梅  朱瑞芳 《护理研究》2006,20(36):3352-3353
文章编号:1009-6493(2006)12C-3352-02麻醉药品的管理是医院管理工作的一项重要任务,如果管理有方,使用得当,可以治病;如果失之管理,使用不当,危害生命健康及社会治安。2005年8月3日,国务院颁布了《麻醉药品和精神药品管理条例》以来我院采取了各种有效的相关措施,保证了麻醉药品的合理使用,取得了良好的社会效益。现将我院严格管理麻醉药品的方法介绍如下。1严格建卡要管理好麻醉药品,首先要严格建卡,建卡时要手续齐全。1.1户口本病人的户口要在建卡医院管辖区内,如超出所管辖区,应有三级甲等医院的证明或肿瘤专病医院的证明及病历。1.2病…  相似文献   
994.
骨髓间充质干细胞向肝细胞的横向分化   总被引:1,自引:0,他引:1  
目的:综合分析骨髓间充质干细胞向肝细胞分化的研究现状及应用前景。资料来源:应用计算机检索Pubmed 2000—01/2005—04有关干细胞及其向肝细胞横向分化方面的文献,检索词“stem cell,hepatoeyte.transdifferentiation”,并限定文章种类为English。资料选择:对检索到的有关干细胞及其向肝细胞横向分化方面的文献进行整理,选取针对性强的文章。同一领域的文献则选择近期发表或权威杂志的文章。资料提炼:共检索到45篇相关文献,其中38篇符合要求,7篇为重复同一研究而排除。资料综合:利用骨髓间充质干细胞在肝损伤等病理状态下具有分化为肝细胞的特性,实现肝组织重建,纠正肝细胞代谢和合成功能障碍,为治疗肝炎、肝硬化、肝癌及肝代谢性疾病提供了新的策略。干细胞在肝病治疗中的应用无疑是对传统治疗方式的挑战。结论:多数学者的研究表明,干细胞具有分化为肝细胞及胆管细胞样细胞的潜能,但也有少数学者持否定意见。目前对于移植后干细胞是产生细胞融合还是分化作用尚存在争议。  相似文献   
995.
996.
Attitudes toward monetary and nonmonetary incentives for living (LD) and deceased donation (DD) among the U.S. general public and different racial/ethnic and income groups have not been systematically studied. We studied attitudes via a telephone questionnaire administered to persons aged 18-75 in the continental United States. Among 845 participants (85% of randomized households), less than one-fifth participants were in favor of incentives for DD (range 7-17%). Most persons were in favor of reimbursement of medical costs (91%), paid leave (84%) and priority on the waiting list (59%) for LD. African Americans and Hispanics were more likely than Whites to be in favor of some incentives for DD. African Americans were more likely than Whites to be in favor of monetary incentives for LD. Whites with incomes less than $20 000 were more likely than Whites with greater incomes to be in favor of reimbursement for deceased donors' funeral expenses or medical expenses. The U.S. public is not generally supportive of incentives for DD, but is supportive of limited incentives for LD. Racial/ethnic minorities are more supportive than Whites of some incentives. Persons with low income may be more accepting of certain monetary incentives.  相似文献   
997.
High tibial osteotomy changes the patella and tibial condyle position, which makes the subsequent total knee replacement technically demanding. From 1 January 1993 to 31 December 2000, combined osteotomy [After the first osteotomy made 2 cm distally to the joint line, a bone wedge is removed based laterally. Its tip ends at the center of the tibial condyle (half bone wedge). The distal part of the tibia is placed into the valgus position and the half bone wedge is placed into the gap opened medially.] was performed on 103 knees and closing wedge osteotomy was performed on 47 consecutive knees. Eighty combined (group A) and 41 closing wedge (group B) osteotomy were studied. All knees were assessed radiologically before surgery, in the 10th postoperative week, in the 12th postoperative month and at the time of the final follow-up (in group A—66.15 months, in group B—66.61 months). We examined the change of the femorotibial angle, of the patellar height according to the method of Insall and Salvati, of the tibial slope angle according to the method of Bonnin, of the tibial condylar offset according to the method of Yoshida and of the distance between the lateral tibial plateau and the top of the fibular head. In group A and B, the recurrence of the varus deformity was not noted and valgus alignment did not increase in any case. In group-A, the Insall–Salvati ratio remained unchanged in 65% of knees. The tibial slope angle decreased in both groups. There was correlation between the change of the tibial condylar offset and the angle of the correction in both groups. There was correlation between the change of the distance between the lateral tibial plateau and the top of the fibular head. After combined osteotomy, the transposition of the tibial condyle and the decrease of the distance between the lateral tibial plateau and the top of the fibular head was less than after closing wedge osteotomy, although the average angle of correction was more after combined osteotomy (11.835°), than after closing wedge osteotomy (9.465°). Theoretically, the recurrence of the varus deformity, the increase of the valgus alignment and (in majority of cases) the shortening of the patellar tendon do not compromise the likelihood of successful conversion to the subsequent total knee replacement, either after combined or after closing wedge osteotomy. The combined osteotomy does not lead to considerable transposition of the tibial condyle and to considerable lateral tibial bone loss; therefore, theoretically, the combined osteotomy does not impair the subsequent total knee replacement.  相似文献   
998.
蛋白酶对降低异常精液粘稠度的实验对比研究   总被引:1,自引:0,他引:1  
目的通过不同蛋白酶类对降低高粘稠度精液的粘稠度效果对比,寻找理想的降低精液粘稠度的药物。方法将高粘稠度精液标本分为两组,A组:31例采用α-糜蛋白酶降低精液粘稠度:B组:32例采用尿激酶降低精液粘稠度;两组均观察用药前后的精子活动力。采用配对t检验和单因素方差分析对所得数据作统计学处理。结果高粘稠度精液用药物(α-糜蛋白酶或者尿激酶)液化精液后,精子的活动力较用药前有明显提高(P<0.001);用药前后精液的粘稠度都存在着明显的差异,精液的粘稠度分别下降44.83%和55.45%(P<0.001);在A组和B组的对比研究中,单因素方差分析检验提示:用药后两组间粘稠度数据有显著的差异(P<0.001£(?)。结论蛋白酶可以有效地降低异常精液粘稠度的精液,从实验结果提示尿激酶降低精液粘稠度的效果优于α-糜蛋白酶,这有助于临床开展应用性研究和治疗。  相似文献   
999.
Acetylcholine (ACh) induces nasal congestion at low doses but decongestion at high doses. The current study investigated the vascular mechanisms underlying this biphasic nasal airway response in dogs. Collecting and outflow veins from anterior and posterior nasal venous systems and the septal mucosa (containing sinusoidal venous plexuses) were isolated. The in vitro isometric tension of the vascular segments was monitored to reflect vascular reactivity. Immunohistochemical localisation of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase and endothelial nitric oxide synthase (eNOS) was performed. ACh did not affect the venous plexuses but contracted the anterior collecting vein and the outflow veins of both systems in a concentration-dependent manner; the responses were unaffected by nitro-L-arginine-methyl-ester (L-NAME). ACh relaxed posterior collecting veins at low concentrations but contracted them at higher concentrations; L-NAME enhanced the contractions but inhibited the relaxations, with the inhibition reversed by L-arginine. NADPH-diaphorase and eNOS were located predominantly in the posterior collecting veins. The fact that acetylcholine at low concentrations relaxes posterior collecting veins but contracts other collecting and outflow veins implies that the agonist in vivo may induce nasal congestion by increasing posterior blood volume. At higher concentrations, acetylcholine contracts posterior collecting veins as well, implying diminished blood volume in both venous systems, and consequently nasal decongestion. The induced contraction in posterior collecting veins is nitric oxide-independent, while the induced relaxation is nitric oxide-dependent.  相似文献   
1000.
BACKGROUND: Cognitive impairment after stroke associates with various factors, such as age, educational years, etc. Besides concerning about the recovery of limb function after stroke, we should also focus on the rehabilitation of cognition. Moreover, we'd better pay attention to the control of all the risk factors of stroke, and improve the quality of life in stroke patients. OBJECTIVE: To analyze the factors that affect cognitive impairment after stroke. DESIGN: A related factors analysis. SETTINGS: Department of Neurology of Dalian Port Hospital and Dalian Second People's Hospital. PARTICIPANTS: Totally 148 stroke inpatients were selected from Department of Neurology, Dalian Port Hospital and Dalian Second People's Hospital from April 2004 to December 2005, including 100 males and 48 females, aging 45-75 years with an average age of (67±8) years; Their educational years ranged 2-10 years with an average of (6.1±3.7) years; The disease course ranged 15-30 days; All were right-handed. Inclusive criteria: All were accorded with the diagnostic standard set by the Fourth National Academic Meeting for Cerebrovascular Disease; Confirmed by CT or MRI; Informed consents were obtained from all the subjects. METHODS: After the disease conditions were stable, the patients were assessed with Wechsler memory scale (WMS) and Wisconsin card sorting test (WCST). WMS included forward and backward recitation of numbers and short-term memory (verbal memory, visual recognition). The number of times for correct and wrong classifications in WCST and the time to complete the trail making tests A and B were recorded. The focal volume, area and layer were recorded at 24 hours after admission. The general data of the patients were recorded, including name, sex, age, educational years, history of hypertension, history of diabetes mellitus. Electroencepalograph (EEG) was examined to record the wave shape, blood lipids were detected, and the cognition related indexes were analyzed with the Pearson correlation analysis. The correlation between cognitive indexes after stroke and the influencing factors were analyzed with multiple linear regression analysis. MAIN OUTCOME MEASURES: ① Correlation between cognitive indexes and imaging indexes; ② Influencing factors for cognitive indexes after stroke. RESULTS: All the 148 stroke patients were involved in the analysis of results. ① Correlation between cognitive indexes and CT indexes: There were obvious negative correlations between numerical symbol and focal layer (r =-0.234, P < 0.05), as well as between verbal memory and the focal area and volume (r =-0.363, -0.279, P < 0.05); Trail making test A had obvious positive correlation with focal area and volume (r =0.256, 0.256, P < 0.05). Results of multiple linear regression analysis: Correct classification was correlated with triglyceride (partial wave and θ wave (partial regression coefficient=0.231-0.908, P < 0.05); Verbal memory was correlated with EEG α wave, focal volume, sex, educational years and diabetes mellitus (partial regression coefficient=0.219-1.017, P < 0.05-0.01). Visual recognition had correlation with educational years and hypertension (partial regression coefficient=0.326, -1.163, P < 0.01). Trail making tests A and B were correlated with focal volume (partial regression coefficient=4.680, -18.561, P < 0.05). CONCLUSION: The factors that affect the cognitive function after stroke include sex, age, educational years, hypertension, diabetes mellitus, triglyceride, EEG wave shape, and the focal area, volume and layer  相似文献   
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