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1.
3种霍乱弧菌检测方法在外环境标本中的应用研究   总被引:2,自引:1,他引:1  
目的:通过改进霍乱弧菌检测的技术手段,提高外环境标本中霍乱弧菌的检出率。方法:将常规分离鉴定法、PCR检测法和胶体金免疫层析试验法同时用于检测霍乱流行期间的外环境标本,并对其现场应用结果进行比较分析。结果:3种方法检测80份外环境标本霍乱弧菌的结果显示:它们均未出现假阳性,3种方法各有优势,且结果相互符合性好,但也存在各自弱点。结论:只用单一种方法来检测外环境标本霍乱弧菌存在明显不足。建议在外环境霍乱监测中选用胶体金法进行初筛,再用常规法和PCR法检测。最大限度减少漏检的可能性。  相似文献   
2.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
3.
侧脑室注射链脲霉素引起大鼠脑Aβ1-40和Aβ1-42表达增加   总被引:3,自引:0,他引:3  
褚文政  钱采韻 《医学争鸣》2005,26(15):1356-1358
目的:探讨大鼠侧脑室注射链脲霉素(Streptozotocin,STZ)阻断脑内胰岛素信号传导与Aβ表达的关系.方法:24只SD大鼠随机等分为手术组和对照组(n=12),手术组双侧侧脑室注入STZ 3 mg/kg,第3日重复此剂量,对照组只手术操作但不注射药物.21 d后,采用免疫组化方法观测各组大鼠大脑皮层和海马区的Aβ1-40和Aβ1-42阳性表达.结果:与对照组相比,手术组皮层、海马Aβ1-40和Aβ1-42阳性细胞明显增多.结论:侧脑室注射STZ可以引起脑内Aβ表达增多,提示胰岛素/胰岛素受体系统障碍与阿尔茨海默病(AD)发病有密切关系.  相似文献   
4.
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.   相似文献   
5.
目的 观察磁性远红外寝具对高脂血症患者血脂、血糖及抗氧化作用的影响。方法 60例高脂血症患者,按随机数字表法分为实验组(30例)和对照组(30例)。实验组每晚(6~8h)均使用磁性远红外寝具,连续2个月。对照组用普通寝具。两组均于实验前后取全血,测定血脂、血糖及抗氧化指标等。结果 实验组实验后血清总胆固醇,甘油三酯含量明显低于实验前;实验前后血清高密度脂蛋白胆固醇(HDL-ch)含量及血糖无明显变化(P〉0.05)。实验组实验后MDA含量较实验前显著下降(P〈0.05),而血清超氧化物歧化酶(SOD)活性较实验前显著提高(P〈0.01);实验前后血清中NO含量无明显变化(P〉0.05)。对照组实验前后以上各项指标较实验前均无明显变化,差异均无显著性(P〉0.05)。结论 磁性远红外寝具对高脂血症患者具有降血脂作用及抗氧化作用。  相似文献   
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7.
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches.  相似文献   
8.
In patients with PG-dependent renal function, NSAID administration constantly reduces GFR and RBF in a dose-dependent fashion. In this situation, the risk of overt acute renal failure is high and should be taken into proper account. In contrast, the incidence of NSAID-related renal structural alterations appears to be very low, yet the absolute number of patients may be significant considering the wide use of such drugs. Concerning the antiproteinuric effect of NSAIDs, the unfavourable ratio risk/benefit does not seem to support their indication in proteinuric nephropathies. The development of PGHS-2 selective inhibitors is promising, and may open new therapeutical strategies in the treatment of the progression of renal disease.   相似文献   
9.
10.
Bile duct calculi in patients with primary sclerosing cholangitis   总被引:1,自引:0,他引:1  
  相似文献   
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