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11.
用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。  相似文献   
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Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
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BACKGROUND: Atrial fibrillation (AF) is considered a predictive factor of poor clinical outcome in patients with an ischemic stroke (IS). This study addressed whether the impact of AF on the in-hospital mortality after first ever IS is different according to the patient's gender. METHODS: We prospectively studied 1678 patients with first ever IS consecutively admitted to two University Hospitals. We recorded demographic data, vascular risk factors, and the stroke severity (NIHSS) at admission analyzing their impact on the in-hospital mortality and on the combined mortality-dependency at discharge using a Cox proportional hazards model. Two variable interactions between those factors independently related to in-hospital mortality and combined mortality-dependency at discharge were tested. RESULTS: Overall in-hospital mortality was 11.3%. Cox proportional hazards model showed that NIHSS at admission (HR: 1.178 [95% CI 1.149-1.207]), age (HR: 1.044 [95% CI 1.026-1.061]), AF (HR: 1.416 [95% CI 1.048-1.913]), male gender (HR: 1.853 [95% CI 1.323-2.192) and ischemic heart disease (HR: 1.527 [95% CI 1.063-2.192]) were independent predictors of in-hospital mortality. A significant interaction between gender and AF was found (p = 0.017). Data were stratified by gender, showing that AF was an independent predictor of poor outcome just for woman (HR: 2.183 [95% CI 1.403-3.396]; p < 0.001). The independent predictors of combined mortality-disability at discharge were NIHSS at admission (HR: 1.052 [95% CI 1.041-1.063]), age (HR: 1.011 [95% CI 1.004-1.018]), AF (HR: 1.197 [95% CI 1.031-1.390]), ischemic heart disease (HR: 1.222 [95% CI 1.004-1.488]), and smoking (HR: 1.262 [95% CI 1.033-1.541]). CONCLUSIONS: The impact of AF is different in the two genders and appears as a specific ischemic stroke predictor of in-hospital mortality just for women.  相似文献   
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锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
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Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
19.
We summarize the clinical history and laboratory results following the introduction of tenofovir among 6 patients coinfected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) who presented with severe liver disease while receiving lamivudine-based highly active antiretroviral therapy. In all cases, the introduction of tenofovir led to a sustained undetectable HBV and HIV loads, with marked clinical and laboratory improvement in liver function. We provide supporting evidence for the role of tenofovir in the management of advanced HBV infection in HIV-positive patients after the development of lamivudine resistance.  相似文献   
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