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101.
本文以大鼠为实验对象,观察了γ线8Gy照后胃组织内乙酰胆碱含量、胆碱酯酶活性及平滑肌对乙酰胆碱反应性的变化。结果表明,照后1/24~l天胃组织内乙酰胆碱含量明显下降,3天趋向正常,5天基本恢复至照前水平。胃组织的胆碱酯酶活性在照后l/24~5天基本无改变。在同一剂量照后1h,胃窦平滑肌对乙酰胆碱的反应与照前近似,l天后开始减弱,3天后明显下降,与正常相比有非常显著差异。  相似文献   
102.
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material.  相似文献   
103.
不同雾化吸入方式对婴幼儿支气管肺炎治疗效果的影响   总被引:1,自引:0,他引:1  
分析病区库房物资管理中存在的问题,主要有管理意识缺乏,物资领取与临床需求脱节,医疗物资分配和使用不合理,物资的保管、维护不当。应对措施:加强医疗成本管理意识;物资领取时注意计划性和灵活性相结合;库房物资使用时注意原则性和节约性相结合;库房物资规范存放,做好各类固定资产的维护、保养管理;健全病区库房管理规章制度;树立科学发展观。  相似文献   
104.
国产奎硫平合并舒必利治疗难治性精神分裂症   总被引:1,自引:0,他引:1  
目的:了解舒必利合并国产奎硫平(启维)治疗难治性精神分裂症的疗效和安全性。方法:26例符合CCMD-Ⅲ精神分裂症诊断标准且临床判断属于难治性病人,予舒必利合并奎硫平治疗,疗程8周,分别在治疗前及治疗后进行阳性与阴性症状量表(PANSS)和不良反应状量表(TESS)评定。结果:合并治疗8周后总有效率65.3%。PANSS阳性、阴性及一般精神病理评分于治疗前后均有显著差异(P<0.01)。TESS总分治疗前后无显著差异(P>0.05)。副反应主要为肌张力增高、失眠、体重增加、静坐不能。结论:对于舒必利治疗反应不佳的难治性精神分裂症病人合并奎硫平治疗仍可取得较好的临床效果,安全性较高,耐受性及依从性好,可作为临床治疗难治性病人的方法之一。  相似文献   
105.
Two triazaspirodienes, having similar phenoxy propyloxy side chain, were identified as potent mammalian dihydrofolate reductase inhibitors; one having a 6,5‐spiro bicyclic ring system (IC50 = 2.3 nm ) and the other a 6,6‐spiro bicyclic system (IC50 = 6.9 nm ). They also showed more than 50% antiproliferative activity against the MCF‐7 breast cancer cells at 20 μm . This study demonstrated the potential lead of the diamino‐triazaspirodienes in anticancer chemotherapeutical agents’ discovery.  相似文献   
106.
Context Residents in all disciplines serve as clinical teachers for medical students. Since the 1970s, there has been increasing evidence to demonstrate that residents wish to teach and that they respond positively to formal teacher training. Effective resident‐as‐teacher (RaT) programmes have resulted in improved resident teaching skills. Current evidence, however, is not clear about the specific features of an effective RaT programme. Objectives This study was performed in order to investigate the effectiveness of RaT programmes on resident teaching abilities and to identify the features that ensure success. Methods of assessment used to ascertain the effectiveness of RaT programmes are also explored. Methods The literature search covered the period between 1971 and 2008. Articles focusing on improving resident teaching skills were included. Each study was reviewed by two reviewers and data were collected using a standard abstraction summary sheet. Study outcomes were graded according to a modified Kirkpatrick's model of educational outcomes. Results Twenty‐nine studies met review inclusion criteria. Interventions included workshops, seminars, lectures and teaching retreats. Twenty‐six studies used a pre‐ and post‐intervention outcome comparison method. Subjective outcome measures included resident self‐evaluation of teaching skills or evaluation by medical students, peers and faculty members. Objective outcome measures included written tests, evaluation of teaching performance by independent raters and utilisation of objective structured teaching examinations. One study objectively measured learning outcomes at the level of medical students, utilising the results of an objective structured clinical examination. Overall resident satisfaction with RaT programmes was high. Participants reported positive changes in attitudes towards teaching. Participant knowledge of educational principles improved. Study methodologies allowed for significant risks of bias. Conclusions More rigorous study designs and the use of objective outcome measures are needed to ascertain the true effectiveness of RaT programmes. Future research should focus on determining the impact of RaT programmes on learning achievement at the level of medical students.  相似文献   
107.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.  相似文献   
108.
109.
婴幼儿癫痫的外科治疗   总被引:4,自引:1,他引:3  
目的探讨婴幼儿癫痫外科的手术意义。方法从2002-2005年有12例婴幼儿因海绵状血管瘤(4例)、发育不良神经上皮肿瘤(DNTs)(2例)、Sturge.weber综合征(1例)、半侧巨脑病(2例)、外伤后脑膜脑疤痕(1例)、脑脓肿疤痕组织(1例)、脉络丛乳头瘤(1例);由分别位于额(2例)、颞(4例)、顶(2例)、枕(2例)与额顶及颞顶(各1例)病变所致均为灾难性癫痫。当年龄在9—32(平均21.5)个月龄时做了病变及致痫灶切除/功能性大脑半球切除。癫痫开始于出生后5~20 (平均11.8)个月,每天或每周发作多次,抗痫药物治疗无效。患儿做手术评估是6—22(平均12.8)个月。3例患儿有偏瘫,7例显示有缓慢发展的认知功能减低表现。MRI、PET及V-EEG都证实了病灶及致痛灶。结果手术后无死亡及新的神经症状缺失。8例解除了癫痫(EngelⅠ级);2例罕有发作(EngelⅡ级);2例有值得的(worthwhile)改善(EngelⅢ级),7例认知功能也有改善,3例偏瘫者2例有改善。结论灾难性癫痫婴幼儿仔细选择手术病例,外科可以减轻、解除癫痫的疾苦。  相似文献   
110.
PURPOSE: To determine if deliberate hypotension decreases blood loss and transfusion requirements in patients undergoing orthopedic surgery, a systematic review of all randomized trials addressing this issue was undertaken. METHODS: Electronic databases, citations lists and review articles were searched for potential articles. Relevant articles met the following inclusion criteria: English language, humans undergoing orthopedic surgery, deliberate hypotension used by any method, intraoperative blood loss measured as an outcome, and the trial methodology being randomized and controlled. Four outcomes were analyzed, including estimated blood loss, blood transfused, surgery duration, and quality of the surgical field. For all analyses, the random-effects model was used. RESULTS: Seventeen articles met the inclusion criteria. The surgeries studied included total hip arthroplasty (seven), orthognathic surgery (eight), total knee arthroplasty (one) and spinal fusion (one). A total of 636 patients were randomized across all studies. For blood loss, the overall weighted mean difference favoured treatment, with a savings of about 287 mL of blood [95% confidence interval (CI): -447, -127]. The mean differences also showed a statistically significant benefit for deliberate hypotension in reducing transfusion requirements (-667 mL of blood transfused; 95% CI: -963, -370). Deliberate hypotension was not shown to reduce the duration of surgery (-1.9 min of surgery; 95% CI: -7.2, 3.5) or improve surgical conditions (surgical field quality rating -0.5; 95% CI: -1.1, 0.2). CONCLUSION: This review provides some support for the use of deliberate hypotension in reducing blood loss and transfusion requirements in orthopedic surgery, but these results are tempered by the small sample sizes and poor methodological quality of published studies.  相似文献   
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