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51.
目的建立了一种高效液相色谱-三重四极杆串联质谱法,对氯沙坦钾原料药中遗传毒性杂质N-亚硝基-N-甲基-4-氨基丁酸(NMBA)进行测定。方法色谱柱为岛津Shim-pack XR-ODSⅡ色谱柱(2.0 mm×150 mm,2.2μm),流动相为0.1%甲酸水溶液(A)和甲醇(B),进行梯度洗脱,流速0.3 mL·min^-1,柱温为40℃,采用ESI离子化-三重四极杆质谱多反应监测(MRM)正离子模式检测,碰撞电压分别为-11,-13和-13 V,碰撞气氩气270 kPa,NMBA的离子对分别为m/z 147.15→117.10,147.15→87.10和147.15→44.10。结果该方法中NMBA在1~100 ng·mL^-1内线性关系良好,日内和日间的保留时间和峰面积的重复性良好(RSD均小于1.10%,n=6和n=18),低、中、高3个浓度的平均回收率在94.40%~98.04%之间。结论本方法简单方便,可快速有效的对氯沙坦钾原料药中NMBA进行限度检查并实现定量分析。 相似文献
52.
Exercise induced dyspnoea (EID) is a common manifestation in children and adolescents. Although EID is commonly attributed to exercise induced bronchoconstriction, several conditions other than asthma can cause EID in otherwise healthy children and adolescents. Cardiopulmonary exercise testing (CPET) offers a non-invasive comprehensive assessment of the cardiovascular, ventilatory and metabolic responses to exercise and is a powerful diagnostic and prognostic tool. CPET is a reproducible, non-invasive form of testing that allows for comparison against age- and gender-specific norms. CPET can assess the child’s exercise capacity, determine the limiting factors associated with this, and be used to prescribe individualised interventions. EID can occur due to asthma, exercise induced laryngeal obstruction, breathing pattern disorders, chest wall restriction and cardiovascular pathology among other causes. Differentiating between these varied causes is important if effective therapy is to be initiated and quality of life improved in subjects with EID. 相似文献
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《Journal of Clinical Orthopaedics and Trauma》2019,10(5):995-998
BackgroundProper patellar tracking is one of the most important aspect of TKA to ensure good functional outcome. A patellar tracking problem noted intraoperatively serves as a warning sign and should prompt the surgeon to reassess position of each component. Various tests are there to assess lateral retinaculum tightness viz. "No thumb test", "Towel clip test". A new test "Vertical patella test" is described to assess lateral retinaculum tightness. A study was conducted to assess the effectiveness, correlation and validity of two techniques.Materials & MethodsPatients >50 years of age and with diagnosis of Osteoarthritis knee having less than 30 varus and flexion deformity going in for primary TKA were selected with a sample size of 100 knees in a tertiary care centre. Revision cases or patients with flexion contracture more than 30, complex knee surgery; with pre existing patellar tilt were excluded from study.ResultsResults of both tests were found to correlate in 75% of case with sensitivity of 96.65% and specificity of 75.00%. Kappa came out to be 0.634 which shows good agreement of vertical patella test and towel clip test. Result was computed using excel and SPSS and was found to be significant with p value< 0.05. Lateral retinaculum release was done in 8 knees.ConclusionsVertical patella test correlates with towel clip test, is easy to perform and saves time. The limitation of our study was small sample size. 相似文献
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子宫内膜异位症其异位内膜组织虽然在形态学上呈良性表现,却具有类似恶性肿瘤的生物学特性。中医学一般认为,“正虚伏邪”为恶性肿瘤的病机特点;那么,肾虚血瘀既属于“正虚伏邪”的范畴,又体现了EMs发病学和疾病发生、发展过程中的主要特点。在“病证相应”的中医治则之下,补肾化瘀法的临床疗效主要表现为:缓解痛经症状、提高受孕率,以及调整月经周期。本文基于EMs与恶性肿瘤的相关性,通过分析补肾化瘀法治疗EMs的理论依据及其抑制异位内膜侵袭的调控机制,主要包括解除免疫抑制、阻断局部微血管新生等,旨在阐明其疗效显著的原因,为临床推广提供可靠的基础研究证据。 相似文献
57.
Tau Ming Liew 《Journal of the American Medical Directors Association》2019,20(8):1054.e11-1054.e20
ObjectivesEarly diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.DesignCross-sectional diagnostic study.SettingAlzheimer's Disease Centers across the United States.ParticipantsOlder participants (≥50 years) who completed MoCA and the FNB (N = 9187).MeasuresThe study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.ResultsA 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.Conclusions/ImplicationsUsing rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients’ access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment. 相似文献
58.
经穹隆结膜入路埋线法重睑成形术应用探讨 总被引:1,自引:0,他引:1
目的:通过分析重睑形成原理,综合比较多种重睑成形的方法,讨论埋线法重睑成形术的优点和可行性。方法:对387例患者行经穹隆结膜入路间断缝合埋线法重睑术。其中88例为其他方法埋线后重睑线消失的患者。结果:手术方法可靠,术后所形成的重睑外形良好,重睑维持时间长。最长随访时间38个月。结论:此方法因符合重睑形成原理,可以充分的将较多的上睑提肌腱膜与上睑皮肤结扎固定、故术后所形成的重睑牢固。且在直视下经穹隆结膜入路,降低了对眼球组织损伤的危险性。是埋线法重睑成形术一种可靠的手术方法。 相似文献
59.
60.
雷波 《中国脊柱脊髓杂志》2006,(6)
通过对影响杆菌肽抑菌圈大小的各种因素的研究,从而得到提高地衣芽抱杆菌发酵杆菌肽的产量及测量的最佳效果。研究结果表明豆芽汁培养基发酵的杆菌肽产量最高,并且在豆芽汁中加糖量为2g/dL时,抑菌圈最大。管碟法测定时,培养基的厚度影响最为显著,下层厚度10mL,上层5mL最佳,上层培养基的酸碱度为7.0,指示菌的浓度在10^8cfu/mL时,抑菌圈最清晰,直径最大,平均直径为2.52cm。 相似文献