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61.
本文应用核磁共振法(NMR)测定了几种混合体系的 HLB 值与混合体系中各组分的 HLB 值。实验结果表明,混合体系中各组分在核磁共振图谱中的积分曲线高度也具有加和性。混合体系的 HLB 值是体系中各组分 HLB 值的加权平均值。因此,对混合体系的 HLB 值可以应用 NMR 法直接测定,也可应用 NMR 法测定各组分的 HLB值,通过计算求得,计算值与实测值完全一致。 相似文献
62.
End-systolic pressure-volume relations (ESPVRs) were analyzed in 10 closed-chest autonomically blocked dogs before and after volume loading that restored end-diastolic volume to its value measured in the control conscious state. Dogs had been previously instrumented with a left ventricular pressure micromanometer and ultrasonic crystals for measurements of major, anteroposterior, and septum-free wall diameters. Left ventricular volume was calculated with an ellipsoidal model in the left ventricular cavity. ESPVRs obtained during caval occlusion after volume loading were curvilinear as shown by the division of the relation into two parts. The initial part of the relation had a significantly smaller ESPVR slope (Ees, 12.0 +/- 1.8 mm Hg/ml) and ESPVR volume-axis intercept (Vd, - 3.5 +/- 0.8 ml) than the final part of the relation (19.5 +/- 3.1 mm Hg/ml and 0.0 +/- 0.6 ml, respectively, p less than 0.01). The end-diastolic volume-peak dP/dt relation showed a similar curvilinearity when end-diastolic volumes were larger than 1.5-1.7 times the minimal end-diastolic volume reached during caval occlusion. ESPVRs were not different during aortic constriction and caval occlusion when end-diastolic volume was small. In contrast, with large end-diastolic volumes, Ees and Vd were significantly smaller during caval occlusion than during aortic constriction. The final part of ESPVR (with small end-diastolic volume) had the same slope and intercept as that during aortic constriction. We conclude that preload produces a curvilinearity of ESPVR that significantly modifies derived indexes when the range of preload changes is large. 相似文献
63.
为运用循证医学方法对中药熏洗治疗膝骨性关节炎(OA)的临床疗效及安全性进行系统评价和Meta分析。全面收集了中药熏洗治疗OA的文献资料。在严格质量评价基础上,对研究结果进行定性分析。合并各篇优、良为阳性结果,中、差为阴性结果。利用RevMan4.1软件对多个研究结果的总体疗效进行固定效应模型的Meta分析,并进行敏感性分析。用漏斗图表示发表性偏倚。结果显示,中药熏洗治疗OA的效应值OR=2.68.95%可信区间为[1.82,3.95];敏感性分析显示效应值稳定;漏斗图图形不对称;无中药熏洗不良反应的报道。表明中药熏洗治疗OA有一定的疗效,由于漏斗图提示存在发表性偏倚,加上现有临床研究存在的方法学问题,现在的研究结论有一定的局限性,欲得出公认的结论,尚有待进行设计严谨的多中心、随机对照试验。 相似文献
64.
Overview of the Clinical Efficacy of Lamotrigine 总被引:5,自引:4,他引:1
Summary: Testing the efficacy of lamotrigine (LTG) in epileptic patients has been approached in several ways. The first pilot study examined the effect of a single dose of LTG in patients with frequent interictal spikes, and a reduction in spike frequency was observed. Subsequently, single doses reduced photosensitivity in appropriate patients. Single-blind administration of LTG for 1 week in addition to the patients' regular antiepileptic drugs (AEDs), in patients with refractory seizures, reduced seizures despite the short duration of therapy. This regimen was continued using a placebo-controlled crossover study with 1-week duration of treatment. Efficacy in partial and tonic-clonic seizures was subsequently confirmed in four double-blind crossover studies; a meta-analysis of these four studies showed a 30% reduction in partial seizures despite the intractable nature of the seizures in the patients included. Current studies aim at evaluating the drug as monotherapy and in different seizure types. 相似文献
65.
双利肝能显著降低慢性乙型肝炎患者血浆内皮素(ET)水平,使机体细胞免疫功能得以改善,血清乙肝病毒脱氧核糖核酸(HBV DNA)含量显著下降,延长疗程后,能否起到使HBV转阴的效果,有待临床进一步观察。本文观察连续给予双利肝胶囊24周喂养后,对大鼠产生的毒性反应及其恢复过程,为临床用安全剂量提供试验依据。 相似文献
66.
Rapid growth in biomedical research coupled with dramatic advancement in biotechnology has significantly improved our understanding of the molecular basis involving cancer development and progression. This improvement has led to the discovery of new molecular markers for cancer diagnosis and prognosis as well as new molecular targets for cancer treatment and intervention. Continuous emergence of some new developing area in molecular profiling, new therapeutic agents, tissue microenvironment and systems biology have made significant progress in clinical oncology. Clinical research and investigation that focus on these new developments have begun to show exciting results that indicate future promises in improving patient management and survival. 相似文献
67.
The objective of this study is to determine whether a normal fetal morphology ultrasound scan in women older than 35 years reduces the risk of aneuploidy. We reviewed the results of amniocentesis and second trimester sonogram in all women older than 35 years from 1991 to 1995. None had prior screening. We excluded fetuses with structural anomalies. We determined the sensitivity and specificity of minor markers in detecting Down syndrome and also determined the reduction in risk of a normal sonogram. Among the 2060 women older than 35 years giving birth during the study period, 16 (0.78%) delivered an infant with Down syndrome. Of the 16 fetuses, two had no prenatal testing or ultrasound, two had invasive testing but no second trimester sonogram, five had a normal sonogram and seven had one or more sonographic markers of Down syndrome. At least 17% of women older than 35 years did not participate in prenatal testing or ultrasound. Ultrasound detected Down syndrome with a sensitivity of 59% (95% confidence interval: 45–72%), a false‐positive rate of 10.6% (9.4–11.8%) and a positive predictor value of 1 in 9. The likelihood of having normal karyotype if the sonogram was normal was 0.46 (0.31–0.61). In women older than 35 years, a normal second trimester sonogram reduces the risk of Down syndrome by more than 50%. At least 17% of women older than 35 years do not participate in prenatal testing or ultrasound. 相似文献
68.
腹腔镜联合手术728例临床分析 总被引:8,自引:1,他引:7
目的探讨腹腔镜联合手术的优越性。方法回顾分析1992年7月~2006年3月开展腹腔镜联合手术728例临床资料,其中腹腔镜胆囊切除术(laparoscopic choleeysteetomy,LC)联合肝囊肿开窗引流术586例,LC联合阑尾切除术80例,Lc联合卵巢囊肿切除术46例,LC联合肾囊肿去顶引流术16例。结果726例在腹腔镜下完成手术,2例因腹腔粘连中转开腹,无胆道损伤、出血、感染、死亡等并发症发生。512例随访2~60个月,平均16个月,无胆道结石及肝、肾、卵巢囊肿复发。结论腹腔镜联合手术一次性处理两种或两种以上腹部病变是安全有效的,具有创伤小、痛苦轻、恢复快等优点。 相似文献
69.
关于医学生外科临床实习质量的探讨 总被引:2,自引:0,他引:2
外科是一门实践性很强的学科,如何培养实用型医学人才是摆在我们面前的首要问题。本文分析了外科临床实习中存在的问题,并提出一些应对措施。 相似文献
70.
Su Jin Lee Young Keun On Eun Jeong Lee Joon Young Choi Byung-Tae Kim Kyung-Han Lee 《Journal of nuclear medicine》2008,49(8):1277-1282
Vascular 18F-FDG uptake marker represents inflammation in atherosclerotic lesions, but whether inflammation can be reversed by risk-modifying interventions has not, to our knowledge, been demonstrated. In this study, we evaluated the change of vascular 18F-FDG uptake in response to lifestyle intervention on serial PET/CT scans and further assessed how the findings relate to atherogenic risk reduction. METHODS: A total of 60 healthy adults underwent 18F-FDG PET/CT scans and atherogenic risk-factor assessment at baseline and again after 17.1 +/- 8.3 mo of practicing lifestyle modification. The PET/CT images were evaluated for the presence of vascular 18F-FDG lesions, and vessel-to-blood-pool 18F-FDG ratios were measured. Indices from summed ratios of positive lesions were compared and correlated to atherogenic risk factors. RESULTS: At follow-up, significant reductions in diastolic blood pressure (P < 0.05), total cholesterol (P < 0.05), and low-density lipoprotein level (P < 0.05) and an increase in high-density lipoprotein (HDL) level (P < 0.0001) were demonstrated. On the initial PET/CT scan, 50 of 60 subjects showed 1 or more 18F-FDG-positive lesions (5.9 +/- 5.0/subject), leading to a total of 352 vascular sites. On follow-up, 18F-FDG-positive lesions were significantly reduced to 2.1 +/- 2.2 sites per subject (P < 0.0001) and a total of 124 sites (64.8% reduction). Follow-up 18F-FDG-positive rates were significantly reduced for the aorta and iliac arteries. In addition, significant reductions in the whole-body 18F-FDG index from 1.39 +/- 1.23 to 0.53 +/- 0.59 (P < 0.0001) and carotid 18F-FDG index from 0.08 +/- 0.16 to 0.03 +/- 0.06 (P = 0.01) were shown. The whole-body 18F-FDG index correlated with total cholesterol (P < 0.05) and HDL level (P < 0.05), and the magnitude of reduction in the 18F-FDG index closely correlated to the amount of increase in plasma HDL level (P = 0.005). CONCLUSION: Our study demonstrated that vascular 18F-FDG uptake is reversed in response to atherogenic risk reduction by lifestyle intervention and that the magnitude of improvement correlates to increases in plasma HDL levels. Thus, serial 18F-FDG PET/CT may be useful for monitoring improvements in the inflammatory component of atherosclerotic lesions in response to risk modification. 相似文献