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21.
目的 :应用苄基二甲基十四烷氯化铵 (benzyldim ethyltetradecyl amm onium chloride,BAC)建立犬下食管括约肌(L ES)无神经动物模型 ,研究一氧化氮 (NO)对 L ES压力的作用。方法 :将 BAC环周注入犬 L ES,对照组注入等量生理盐水 ,均于注射前及注射后 6周测定 L ES压力 ;并观察 L -精氨酸、D -精氨酸、硝普钠及一氧化氮合酶 (NOS)抑制剂 N-硝基 - L -精氨酸 (L - NNA)对 L ES压力的影响 ;此外还测定了两组犬 L ES中 NO含量和 NOS活性。结果 :BAC处理组 L ES压力 [(4 2 .43±4.19) m m Hg,1m m Hg=0 .133 k Pa]显著高于对照组 [(2 2 .71± 5 .19) mm Hg]。 L -精氨酸可使对照组 L ES压力降低 ;L - NNA使其增高 ,但对 BAC处理组 L ES压力均无影响。硝普钠可降低两组犬 L ES压力。对照组 L ES中 NO为 (6 .0 5 8± 2 .0 6 7)μm ol/g,NOS为 (1.45 8± 0 .146 ) U /mg;而 BAC处理组 NO为 (1.797± 0 .873)μmol/g,NOS为 (0 .46 3± 0 .0 39) U /m g,均较对照组显著降低 (P<0 .0 1)。 结论 :BAC可使犬 L ES压力增高 ,其机制可能与 L ES局部 NO减少有关。  相似文献   
22.
Purpose: As COVID-19 spreads globally and affects people''s health, there are concerns that the pandemic and control policies may have psychological effects on young people (age from 17 to 35 years). This psychological impact might vary in different countries, and thus we compared the prevalence of selfreported psychological distress, loneliness and posttraumatic stress symptoms (PTSS) among young people in the United Kingdom (UK) and China at the beginning of the COVID-19 pandemic. Methods: Data of this study came from two sources. One source was the first wave of COVID-19 study in Understanding Society, a special wave of the UK household longitudinal study, which provided the highquality, national-wide representative panel data. The sample comprised 1054 young people. The other source was an online survey on the mental health of 1003 young people from Shanghai, a highly developed area in China. The questionnaire included questions on the prevalence of common mental disorders (cut-off score ≥ 4), loneliness and potential PTSS (cut-off ≥ 33). Univariable analyses were conducted to test the differences in the self-reported prevalence of psychological distress and loneliness between the two groups. Multivariable logistic regression analyses were run to explore the predictors of psychological distress and loneliness among all the young people from England and Shanghai. Results: Among the samples with self-reported psychological distress, the UK sample accounted for 34.4% (n = 1054) and the Chinese sample accounted for 14.1% (n = 1003). The difference between the two groups was statistically significant (p < 0.001). Additionally, 57.1% of people in the UK and 46.7% in China reported that they sometimes or often felt lonely, of which the difference is statistically significant (p < 0.001). Regression analysis of the entire samples showed that nationality, gender, psychotherapy and loneliness were significant predictors of 12-item General Health Questionnaire scores, while the variables of age and living alone were not. Significant predictors of self-reported loneliness were the nationality, gender, age, living alone and psychotherapy. In China, 123 (12.3%) young people, 49 men (11.3%) and 74 women (13.0%), met the criteria of PTSS symptoms (cut-off scores ≥ 33). These scores were only collected in China. Conclusion: This evidence suggests that mental health and loneliness reported by young people were lower in China than that in the UK during the studied period. More research is needed to understand these differences. If the differential negative psychological impacts are confirmed, country-specific measures of prevention and intervention should be adopted to improve the mental health of young people under the ongoing impact of the pandemic.  相似文献   
23.
目的 本研究旨在比较颅内大血管伴/不伴同侧颈内动脉闭塞的大动脉粥样硬化型脑卒中患者基线特征以及行血管内治疗后结局的差异。方法 对DIRECT-MT亚组进行回顾性分析,以比较前循环大动脉粥样硬化(large-artery atherosclerosis,LAA)型卒中串联闭塞和颅内闭塞接受血管内治疗(endovascular treatment,EVT)的患者的基线特征和预后,分析不同机制学特征(动脉粥样硬化或动脉-动脉栓塞)对临床结局的影响。结果 LAA型卒中患者共108例,其中串联闭塞63例,颅内闭塞45例。颅内闭塞组患者高血压史率高于串联闭塞组(77.8% vs. 52.4%, P=0.007)。颅内闭塞组闭塞部位最常见于大脑中动脉M1段(88.6%),而串联闭塞组颅内闭塞主要位于颈内动脉颅内段(49.2%)和大脑中动脉M1段(49.2%)(P<0.001)。两组患者在年龄、性别、术前抗栓、他汀类药物的使用,卒中、房颤、吸烟史,基线mRS、NIHSS评分,是否静脉溶栓,侧枝循环,以及救治流程时间差异均无统计学意义(P均>0.05)。90天mRS 0-2分的患者比例两组差异无统计学意义(53.3% vs. 41.9%, P=0.243)。颅内闭塞组术后成功再灌注率高于串联闭塞组(93.3% vs. 77.4%, P=0.026),但术后24-72小时血管再通的比例前组低于后组(57.1% vs. 77.2%, P=0.034)。最终梗死体积,颅内闭塞组小于串联闭塞组(20.1 vs. 34.5, P=0.025)。术后NIHSS评分,90天EQ-5D-5L评分和BI指数等其他次要结局,两组间差异无统计学意义(P均>0.05)。两组在90天内的死亡率,发生的无症状性和症状性颅内出血率,5-7天时在另外的血管区域新发脑梗死,以及新流域栓塞的患者百分比相似,差异无统计学意义(P均>0.05)。结论 动脉粥样硬化导致的串联闭塞相较于孤立颅内闭塞,末次造影成功再灌注率较低,梗死体积更大,但术后24-72小时再通率更高,且神经功能良好预后率以及不良事件发生率均与颅内闭塞相仿。  相似文献   
24.
目的:探讨甲状腺大部切除手术应用改良的颈神经丛阻滞麻醉效果。方法:全部病例均采用一点法深浅颈神经丛阻滞。将全部病例随机分为A、B两组(每组30例),深丛均为0.25%布比卡因液或1.14%利多卡因和0.14%地卡因混合液,每侧各约5-6ml。A组为与深丛相同浓度的局麻药液,每侧约8-10ml,B组为与A组所用药同等剂量,但其浓度为A组的2/3(即加入1/3容量的生理盐水),使浅丛容量较A组增加1/3,约为11-13.5ml。结果:两组病人经过顺利,均无并发症。阻滞效果均较好,但A组病人在手术进行到牵拉甲状腺上极时,有12例病人牵拉痛较明显。结论:低浓度高容量法颈丛阻滞,效果可靠、安全、并发症少,是甲状腺大部切除较理想的麻醉方法。  相似文献   
25.
Thefirsttumorsuppressorgenemolecularlyisolatedistheretinoblastoma(Rb).ThedeletionofRbplaysanessentialroleinRetinoblastoma[1].TheosteosarcomaisalsoassociatedwiththedoublelossoftheRbgene[2].AbnormalitiesinthestructureandexpressionoftheRbgenehadbeenidentifiedinsmallcellcanceroflung[3]andbreastcancers[4].ThesefindingssuggestthattheRbgeneisapleiotropicsuppressorgene.Oralsquamouscellcarcinomaisthecommonmalignanttumor,whichaccountsfor80%ofthetotalofmalignanttumorsinoralmaxillofacialregion.Theprog…  相似文献   
26.
27.
老年人就医的伦理思考   总被引:1,自引:1,他引:0  
1 面对老年人就医 ,医务工作者应当具有一种特殊的医德情感 如高度的责任感 ,同情感 ,事业感及理智感等。医院及医务工作者应致力于为老年人创造一个舒适、安静、和谐的环境 ,使他们就医时有一种方便、安全的感觉 ,消除老年患者的紧张、恐惧的心理。当今社会生活节奏的加快 ,给老年人特别是老年住院患者带来了一系列问题。其家人由于工作的繁忙等原因 ,不能及时陪同患者进行治疗 ,使老人在心理上感到压抑、失落、孤独和恐惧 ,加之老年人不管是在生理还是在心理方面承受和抵抗压力的能力都大大减弱 ,容易对自己失去信心 ,这对病情的治疗不…  相似文献   
28.
目的:探讨白内障超乳化摘除,睫状体平坦部下班体切割及人工晶体囊袋内植入联合手术的疗效及安全性。方法:对玻璃体视网膜病普合并白内障18例(18眼)施行该联合手术。其中糖尿病性视网膜病变,玻璃体出血伴白内障10例;视网膜分枝静脉阻塞,玻璃体出血伴白内障4例;视网膜静脉周围炎,玻璃体出血伴白内障3例及特发性视网膜1例,术后随访2~13个月(平均9月)。结果:术后视力均有不同程度提高。12眼(67%)术后  相似文献   
29.
Heat-clearing and hemostatic drugs were effective in treating chyluria. In order to explore the curative mechanism, a group of 10 in-patients with chyluria were chosen and treated with heat-clearing and hemostatic drugs for 45 days. Some pre- and post-treatment skin from dorsum pedis of the patients were taken off and observed under electron microscope. It showed that the walls of lymphatic capillaries were seriously damaged before treatment and rehabilitated wall after treatment. The pinocytotic vesicles were packed tightly in the endothelial cells of capillaries before treatment and their number was decreased remarkably after treatment; the mast cells were rare in number and abnormal as spindle shape before treatment and they increased in number and became round or oval in shape, the nucleus became large, the granules they contained became more in number and larger in size after treatment, lymph edema was noticed before treatment and it disappeared after treatment. The result showed that the extensive lesion of lymphangial walls is the pathogenesis of chyluria, while the rehabilitation of them is the curative mechanism. It seems that in the process of rehabilitation the mast cells act took the role of "soldier-engineer".  相似文献   
30.
盐酸达克罗宁凝胶的制备   总被引:6,自引:0,他引:6  
目的:制备盐酸达克罗宁凝胶。方法:用CMC-Na作基质,制备盐酸达克罗宁凝胶,并建立质控方法。结果:处方设计合理,制备工艺可行,平均回收率为100.4%。RSD=O.8%。结论:该凝胶剂质量稳定可靠,可满足临床使用。  相似文献   
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