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81.
目的 构建结核分枝杆菌Ag85B/GSF融合蛋白表达质粒,并在大肠杆菌(E.coli)中诱导表达。方法 以质粒pUC18/Ag85B为模板,用PCR法扩增结核杆菌Ag85B基因,扩增的Ag85B上游含有EcoR Ⅰ酶切位点,下游含有SalⅠ酶切位点;将Ag85B基因定向插入质粒pGEX-4T-1中,构建原核表达质粒pGEX-Ag85B并转化E.coli B121,筛选阳性重组子,限制性内切酶切鉴定和DNA序列测定,异丙基硫代半乳糖苷(IPTG)诱导表达,SDS-PAGE和Westem blot鉴定结果。结果 成功构建原核表达质粒pGEX-Ag85B并表达出Mr约56000大小的Ag85B/GSY融合蛋白,表达量占总菌体的30%。结论 为进一步进行纯化Ag85B蛋白和研究其在膀胱肿瘤治疗中的作用奠定了基础。  相似文献   
82.
Migraine is a common subtype of headache. Epidemiological studies have revealed that migraine could be an independent risk factor for ischemic stroke even in elderly subjects. Arterial stiffness is one of the major pathophysiological bases of stroke. In the present study, we cross-sectionally investigated the possible relationship between migraine and arterial stiffness in community-dwelling subjects. The study subjects were independently recruited from two sources (Group A, n=134, 68+/-5 years; Group B, n=138, 68+/-7 years). Augmentation index (AI), the ratio of augmented pressure by the reflection pressure wave to the pulse pressure, was obtained from the radial arterial waveform as an index of arterial stiffness. Brachial blood pressure was also measured simultaneously. Migraine was diagnosed using a previously validated questionnaire. The prevalence of migraine was 5.2% (Group A) and 16.7% (Group B). Subjects with migraine had higher radial AI in both Group A (migraine, 101+/-15%; other headache, 88+/-12%; no headache, 86+/-12%, p=0.003) and Group B (95+/-11%, 90+/-11%, 91+/-14%, p=0.058). Multiple linear regression analysis revealed that migraine was an independent determinant of AI (beta=0.154, p=0.002) after adjustment for other confounding factors: age (beta=-0.024, p=0.654); sex (beta=0.141, p=0.069); body height (beta=-0.215, p=0.005); systolic blood pressure (beta=0.174, p=0.001); medication for hypertension, hyperlipidemia, and diabetes mellitus (beta=-0.014, p=0.787); and heart rate (beta=-0.539, p<0.001). In a separate analysis by sex, migraine was also a significant determinant for AI (male, beta=0.246, p=0.019; female, beta=0.159, p=0.008). Migraine in the elderly could be a clinical manifestation of enhanced arterial stiffness.  相似文献   
83.
Pulse-height and time spectra of afterpulses from a scintillation detector with NE102A scintillator sandwiching a 60Co source were observed at several different temperatures. From time analysis with a slow amplifier followed by a conventional TAC, spurious pulses are grouped into two types; time-dependent afterpulses and random noise. The intensity of afterpulses decreased considerably with increasing temperature, while the intensity of random noise pulses increased abruptly above 50 degrees C. Experiments, in which the temperatures of scintillator sheets and of the photomultiplier tube were changed separately, suggested that the time-dependent afterpulses were produced in the scintillator itself, while the random component arose from photomultiplier tube.  相似文献   
84.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
85.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
86.
目的探讨鱼腥草治疗上呼吸道感染所致发热病人的疗效。方法将确诊的病例随机分为2组,治疗组和对照组各30例。治疗组给予鱼腥草、青霉素钠静滴,对照组用病毒唑、青霉素钠静滴。结果治疗组退热时间多在2d以内,对照组多在2d后。治疗组症状消失时间多在5d以内,对照组多在5d以后。差异有统计学意义。结论用鱼腥草和青霉素静滴可缩短发热时间,且症状消失快。  相似文献   
87.
健身宝对衰老模型小鼠血清SOD和MDA的影响   总被引:2,自引:0,他引:2  
目的 研究健身宝补脾益肾、延缓衰老的作用机制。方法 将 60只小鼠随机分为 6组 ,除正常对照组外均每日注射对D -半乳糖造成衰老模型 ,同时给予不同剂量的健身宝和金匮肾气丸。 6周后检测小鼠血清中SOD活性、MDA含量。结果 衰老模型组与正常对照组比较 ,小鼠血清中SOD活性显著降低 ,MDA含量显著升高 (P <0 .0 1 ) ;而健身宝大、中剂量组与正常对照组相比较 ,小鼠血清中SOD活性显著升高 ,MDA含量显著降低 ,与衰老模型组相比较有显著性差异 (P <0 .0 5 )。结论 健身宝明显提升D -半乳糖拟衰小鼠血清中SOD活性 ,降低MDA含量 ,可从调节自由基代谢和提高抗氧化能力方面发挥延缓衰老的作用。  相似文献   
88.
89.
90.
Ilizarov外固定器治疗马蹄内翻足的护理   总被引:3,自引:1,他引:2  
[目的]总结13例马蹄内翻足应用外固定器矫形的护理。[方法]采取心理疏导、针孔护理、密切观察肢体感觉、运动功能,指导正确使用外固定器及康复训练等综合护理。[结果]随访13例患者术后疗效满意,无1例因护理不当出现并发症。[结论]应用外固定器治疗,通过围手术期精心护理,保证了手术的成功,达到了病人的满意。  相似文献   
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