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王安奇 《医学争鸣》2005,26(6):501-501
1临床资料我院自1988年开展经尿道前列腺汽化(TUVP),配合尿道前列腺电切(TUPP)治疗前列腺增生症72例,年龄56~87(平均71)岁,病史1~8(平均4.5)a.术前行国际前列腺症状评分(IPSS)26~32分,B超测定前列腺大小并计算质量,平均为61.8 g.  相似文献   
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One of the efficient and well-known upconverting nanomaterials is NaYF4:Yb,Er@NaYF4, which emits photoluminescence at 545 nm and 660 nm under an excitation of 980 nm. Here, the nonlinearity of β-NaYF4:Yb,Er@NaYF4 at 532 nm is investigated using three nonlinear approaches. For the first time, the nonlinear optical conjugation of NaYF4:Yb,Er@NaYF4 nanocrystals is observed using the degenerate four-wave mixing method. In the optical bistability study, the optical hysteresis of NaYF4:Yb,Er@NaYF4 is measured using the Mach–Zehnder interferometer nonlinear ring cavity, and the results of bistability loops show different behaviors at different power regimes. Finally, the Z-scan technique is used for determining the nonlinear absorption and refraction coefficients, which are calculated in the order of 10−4 (cm W−1) and 10−8 (cm2 W−1), respectively. The results indicate that by increasing incident powers, optical behaviour changes in both optical bistability and Z-scan. Therefore, the results exhibit that the β-NaYF4:Yb,Er@NaYF4 nanocrystals have nonlinear photoresponses at both 980 and 532 nm, which could be promising for photonic devices based on NIR light and visible light.

NaYF4:Yb,Er@NaYF4 is an efficient and well-known upconverting nanomaterials at 980 nm, also it has strong optical nonlinearity at 532 nm related to energy states of the Yb/Er system which is determined by a unique approach.  相似文献   
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培养心肌细胞牵张刺激装置的建立及应用   总被引:2,自引:2,他引:2  
1 方法 牵张刺激装置的制作如模式图 1.制作实验模型采用材料为有机玻璃板、2 4孔培养板、硅胶膜 (厚度 0 .2 2 μm) .硅胶膜从平面圆形变为球形时 ,面积扩大的百分比 =(S球 -S园 ) /S园 ,其中S球 =AD2 ,S园 =r2 ,而AD2 =h2 +r2 ,其中r为孔的半径 ,h为膜升高的高度图 2 .通过控制h的大小 ,可控制膜被牵拉的强度 .本实验采用使膜面积扩大 2 0 %的强度 ,故h =4mm[1] .参照Kassiri等[2 ,3 ] 方法进行心肌细胞的分离培养 .生长有贴壁心肌细胞的 2 4孔板被固定于牵张装置 ,缓慢充气使硅胶膜向上凸起 4mm ,分别维持…  相似文献   
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Chronic hepatitis B virus (HBV) infection may result in cirrhosis and/or hepatocellular carcinoma and is one of the leading causes of mortality in Asian Americans including Hmong Americans. The Central California Valley is home to a huge Hmong population. To date, the true prevalence of HBV among Hmong is largely unknown. The aim of this study was to contribute to the limited data on HBV prevalence and its trends in Hmong population in the Central California Valley. Between fiscal years 2006 and 2010, a total of 219, 450 voluntary donors were identified at Central California Blood Center in Fresno. Of these, 821 (399 males and 422 females) were Hmong donors. A cross-sectional review of the HBV (hepatitis B surface antigen) positivity among all donors was carried out. Prevalence estimates with 95% confidence intervals (CI) were calculated. Ninety-two percent of Hmong donors were between age groups 16 and 35 years, and only 8% were ≥36 years. The overall prevalence in Hmong was noted at 3.41% (95%CI 2.3–4.9) compared to 0.06% (95%CI 0.05–0.07) in donors of all ethnicities. The calculated prevalence could be an underestimate of the true HBV prevalence in Hmong as the study enrolled only healthy blood donors with predominant younger age (≤35 years) population. These results underscore the persistent burden of HBV infection and potentially increased risk of premature death even in the second generation Hmong community of the Central California Valley. This study reemphasizes the unequivocal need to develop robust preventive and treatment strategies for HBV in Hmong community.  相似文献   
7.
The neurotransmitter γ-aminobutyric acid (GABA) is involved in the process of memory. It has been reported that the inhibition of GABAB receptors has beneficial effects on cognition. The aim of this study was to investigate the role of CGP35348 (a GABAB receptor antagonist) on dentate gyrus GABAB receptor inhibition and its effects on learning and memory impairments that had been induced in adult male rats by microinjection of β-amyloid (Aβ). Seventy Wistar male rats were randomly divided into seven groups: control, sham (receiving the Aβ vehicle only), Aβ, Aβ + CGP35348 (1, 10, and 100 μg/μL), and CGP35348 alone (10 μg/μL). Memory impairment was induced by unilateral interventricular microinjection of Aβ (6 μg/6 μL). Rats were cannulated bilaterally in the dentate gyrus, and then, they were treated for 20 consecutive days. Learning and memory were assessed using the novel object recognition and passive avoidance learning tests. The discrimination index and the step-through latency were significantly increased in the Aβ + CGP35348 group in comparison to the Aβ only group (P?<?0.05 and P?<?0.01, respectively). Data showed that the discrimination index was decreased in the Aβ + CGP35348 group in comparison with the control group (P?<?0.05) and sham group (P?<?0.01). Moreover, the step-through latency was significantly decreased in the Aβ + CGP35348 group in comparison to the control and sham groups (P?<?0.01). Data from this study indicated that intra-hippocampal microinjection of the GABAB receptor antagonist counteracts the learning, memory, and cognitive impairments induced by Aβ. It can be concluded that the GABAB receptor antagonist is a possible therapeutic agent against the progression of acute Aβ toxicity-induced memory impairment.  相似文献   
8.
左旋千金藤立定对大鼠阻力动脉的松弛作用   总被引:4,自引:0,他引:4  
石磊  王永信  薛爱琴 《药学学报》1996,31(7):492-495
应用离体阻力动脉技术,研究了左旋千金藤立定(l-stepholidine,l-SPD)对离体阻力动脉的松弛作用。l-SPD对KCl(125mmol·L-1)引起的心、肾、脑、肠系膜的阻力动脉收缩均有松弛作用,其中以脑阻力动脉的松弛作用为最弱,-Log EC50值为4.25±0.22;对肠系膜阻力动脉的松弛作用为最强,-Log EC50值为4.76±0.15。上述结果提示,l-SPD直接松弛内脏阻力动脉、降低外周阻力,可能是其产生降压作用的一个机制。  相似文献   
9.
草珊瑚中的一个新倍半萜内酯   总被引:5,自引:0,他引:5  
草珊瑚为金粟兰科植物Sarcandra glabra(Thumb.)Nakai的全株,又名接骨金粟兰、肿节风、九节风、九节茶、接骨木等。有清热祛风,散瘀接骨之功效,民间用于治疗肺炎、凤湿性关节炎等。近年来做成制剂治疗溃疡病、癌症等。已报导的化学成分有延胡索酸、琥珀酸及异白蜡树定(isofraxidin)等。今从草珊瑚叶中分得一个新的倍半萜内酯,本文鉴定其结构为(—)-istanbulin A。  相似文献   
10.
Renal disease burden following liver transplantation   总被引:2,自引:0,他引:2  
Significant chronic kidney disease (CKD) occurs following orthotopic liver transplant (OLT). Since CKD is associated with increased cardiovascular events, mortality, and hepatic allograft dysfunction, early recognition of CKD and implementation of changes may improve the long-term outcome. The purpose of this study was to determine the burden of renal disease following OLT. PATIENTS AND METHODS: We retrospectively reviewed our OLT recipients from 1997 until 2004. We calculated glomerular filtration rates (GFR) using the Modification of Diet in Renal Disease study (MDRD) method. The GFRs were further subdivided into pre-MELD and post-MELD eras. RESULTS: During the study period, we performed 407 OLTs. We censored data from living donor liver transplants (n = 14), combined liver-kidney transplants (n = 12), and from patients whom we did not have complete data for 6 months after transplant (n = 40). Mean MELD score at the time of transplant was 18 +/- 7 (mean +/- standard deviation). The mean GFR at 6 months following OLT was 63.7 +/- 30.2 mL/min per 1.73 m(2). Only 14% (n = 47) of our patients had normal renal function at 6 months, while 78% (n = 266) of our patients had mild to moderate risk for renal failure. Eight percent (n = 28) had stage 4 or 5 CKD. There were no differences between the pre-MELD and post-MELD GFRs. CONCLUSIONS: The burden of renal disease is significant in our patient population at 6 months posttransplantation. It may be important to introduce CKD management as early as 6 months after transplant to impact the outcomes of OLT recipients.  相似文献   
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