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排序方式: 共有963条查询结果,搜索用时 31 毫秒
1.
目的 建立一种能够快速鉴定人参和西洋参的双重实时荧光PCR方法。方法 通过对人参属及其近似种基因序列的分析比对,设计特异性的引物探针,建立双重实时荧光PCR检测方法。PCR反应体系为Premix Ex Taq (Probe qPCR) 10 μL,人参上下游引物各0.5 μL,西洋参上下游引物各0.3 μL,人参与西洋参特异性探针各0.4 μL,DNA模板2 μL,灭菌去离子水补至20 μL。反应条件为95℃预变性30 s;然后以95℃变性5 s,60℃退火延伸30 s进行40个循环。应用该方法测试了27份DNA样品,包括7份人参、6份西洋参、4份人参与西洋参混合样、10份其他人参属样品及其他常见中药材样品的DNA,以确定该方法的特异性。将人参与西洋参样品DNA混合后10倍稀释成不同浓度后进行检测,用以确定该方法的灵敏度。结果 人参及西洋参样品均在特定的荧光通道下出现典型的阳性扩增曲线,人参与西洋参混合样品均同时出现两条阳性扩增曲线,其它对照样品及空白对照均没有出现阳性扩增曲线。灵敏度检测结果显示该方法检测人参及西洋参的最低检测限均为2 pg DNA/反应。结论 本实验建立的双重实时荧光PCR方法能够同时快速、准确、灵敏地鉴别出人参和西洋参。 相似文献
2.
3.
NIKKISO DBB-27型血液透析机液路系统工作原理及故障报警分析 总被引:1,自引:0,他引:1
分析了NIKKISO DBB-27型血液透析机液路系统的系统结构及各组成部分的工作原理,并对相关故障报警的诊断和排除进行了详细论述,为及时、准确地诊断和排除血液透析机的故障提供了理论基础。 相似文献
4.
黄平 《浙江中医药大学学报》2004,28(4):24-26
目的:观察中药降糖益肾方合二甲双胍片治疗2型糖尿病的临床疗效.方法:治疗组50例口服降糖益肾方、二甲双胍片.对照组45例口服二甲双胍片.两组均连续用药3个月,监测两组治疗前后空腹及餐后2h血糖(FPG、PG2h)、空腹胰岛素(Fins)血脂(TC、TG)及血液流变学指标变化,并计算胰岛素敏感指数(IAI).结果:治疗组临床症状改善、FPG、PG2h、Fins、TC、TG以及血浆粘比度、红细胞压积、纤维蛋白原与对照组比较明显降低,IAI明显提高(P<0.01、P<0.05).结论:中药降糖益肾方合二甲双胍片治疗2型糖尿病疗效确切. 相似文献
5.
Lorenzo E. Derchi Carlo Martinoli Roberto Pontremoli Stefano Saffioti Caterina Pastorino 《European radiology》1993,3(2):186-189
Two patients with arteriovenous fistulas of the native kidney occurring after needle biopsy were evaluated using duplex and color Doppler ultrasonography. The first patient had a fistula with associated pseudoaneurysm: color Doppler showed the lesion as a small rounded area with whirling flow; spectral analysis allowed recognition of both the afferent artery with low impedance flow and the draining vein with pulsatile, arterialized flow. The second patient had a normal color Doppler study; however, spectral analysis demonstrated signals with low vascular impedance from an intra-parenchymal artery at the lower pole, and a jet of turbulent flow. Following disappearance of clinical findings, such Doppler abnormalities were no longer detectable. When a iatrogenic arteriovenous fistula is considered on clinical grounds, both color and Doppler spectral analysis of waveforms from intra-parenchymal vessels should be performed. Possibly, further advances in color Doppler technology will permit the use of this examination as the first imaging procedure in these clinical situations.Correspondence to: L. E. Derchi 相似文献
6.
The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts 总被引:3,自引:2,他引:1
Frauchiger B.; Bock A.; Eichlisberger R.; Landmann J.; Thiel G.; Mihatsch M. J.; Jager K. 《Nephrology, dialysis, transplantation》1995,10(4):527-532
The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 770). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique. 相似文献
7.
选用昆明种小鼠60只,体重18~24克,随机分成三组,每组20只,雌雄各半。通过饮水染毒。一组正常对照,饮自来水,二组饮30ppm含镉水,三组饮300ppm含镉水,染毒时间三个半月。观察指标:体重增长速度、脏器系数、肝肾中镉含量、重点病理形态学改变(光镜和电镜)。结果,30ppm组小鼠肝肾组织有一定病变,300ppm组小鼠的光镜和电镜的病理形态学改变更为明显。提示,小鼠长期摄入镉可引起一定的损害。 相似文献
8.
Summary
The case of a 10-year-old boy with post-traumatic priapism after perineal trauma is presented. Interdisciplinary treatment
using angiography and selective catheter embolization for juvenile high-flow priapism is demonstrated. The literature and
the diagnostic possibilities resulting from color duplex sonography are discussed.
相似文献
9.
Wilke , W. Lee & Person , A. E. G. 1992. Captopril and time dependent changes in post- to pre-glomerular resistance ratios in remnant kidneys of pre-hypertensive rats. Acta Physiol Scand 144 , 253–261. Received 26 June 1991, accepted 8 October 1991. ISSN 0001–6772. Department of Physiology, Colorado State University, Fort Collins, Colorado, USA and Department of Physiology and Biophysics, University of Lund, Sweden. Micropuncture experiments were performed on intact and remnant kidneys of male Sprague-Dawley rats before and after angiotensin converting enzyme inhibition with captopril (0.5 mg kg-1 iv). Partially nephrectomized rats were studied at 2 and 8 weeks post-surgery before the development of systemic hypertension. At 2 weeks, nephrectomized rats had a numerically higher tubular stop-flow pressure than controls (43 ± 2 mmHg vs. 38 ± 2 mmHg; P = 0.08) and a higher post- to pre-glomerular resistance ratio (Re/Ra) (0.40 ± 0.03 vs. 0.31± 0.03; P = 0.08). At 8 weeks, stop-flow pressure and post- to pre-glomerular resistance ratios were similar in remnant and intact kidneys. Captopril had no effect on stop-flow pressure in 2 week post-surgery nephrectomized rats or either control group, but it increased stop-flow pressure in 8 week post-surgery nephrectomized rats (40 ± 2 to 44 ± 2 mmHg, P= 0.04). This increase in stop-flow pressure was associated with an increase in the post- to pre-glomerular resistance ratio (0.33 ± 0.02–0.42 ±0.02, P = 0.009). Stop-flow pressure was positively correlated with the post- to pre-glomerular resistance ratio in 2-week post-surgery nephrectomized rats and their respective controls when combined (r = 0.89, P= 0.0001) and 8-week post-surgery nephrectomized rats and their respective controls combined (r= 0.78, P = 0.0001). Stop-flow pressure was not significantly correlated with mean arterial pressures or welling-point pressures in these groups. We conclude that stop-flow pressure in remnant kidneys of pre-hypertensive rats is primarily determined by the post- to pre-glomerular resistance ratio, and increases in stop-flow pressure and post- to pre-glomerular resistance ratios in remnant kidneys are transient in the absence of systemic hypertension. The role of the renin-angiotensin system in determining the ratio and stop-flow pressure is dependent on time post-nephrectomy. Captopril-induced increases in stop-flow pressure and post- to pre-glomerular resistance ratio at 8 weeks, suggests that its primary effect at that time is not a preferential post-gIomerular vasodilation subsequent to reductions in intrarenal angiotensin II. 相似文献
10.
用电解损毁方法损毁Wistar成年雄性大鼠的双侧蓝斑区。结果出现膀胱扩张、尿液潴留和血尿等,膀胱和输尿管尿液有大量红细胞和血红蛋白,膀胱粘膜和肾脏充血.结果表明:损毁双侧蓝斑区后不仅有膀胱出血,还有肾脏出血。这个实验可用作研究“特发性”血尿的动物模型。 相似文献