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61.
目的:探讨用长链核酸扩增技术评价病毒灭活效果的可行性.方法:针对伪狂犬病毒(pseudorabies virus,PRV)糖蛋白gD基因前后的保守区设计预计产物长短不一的5对引物,用半巢式PCR技术扩增经低pH法(4.0±0.1)、巴氏消毒法[(60±1.0)℃]和s/D法(有机溶剂/洗涤荆)处理后的PRV核酸,同时以细胞感染法做平行对照.结果:低pH对PRV核酸有破坏作用,处理时间越长,核酸损伤程度越明显,处理60 min时,6.62 lgTCID50的PRV完全被灭活.5条不同长度PCR扩增产物中,只有3.9 kb的长片段检出与细胞培养结果一致.7.25 lgTCID50的PRV经(60±1.0)℃处理20 min后即被完全灭活,7.13 lgTCID50的PRV经s/D法处理1 h后被完全灭活,但各长度核酸片段扩增均为阳性,与细胞感染试验结果不符.结论:低pH对PRV核酸的损伤程度随处理时间的延长而增加;用长链PCR(3.9 kb)技术来评价经低pH法灭活病毒的效果是可行的,而该法不适合评价巴氏消毒法和S/D法灭活病毒的效果. 相似文献
62.
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
63.
P. A. da Silva M. M. S. Boffo I. G. de Mattos A. B. S. Silva J. C. Palomino A. Martin H. E. Takiff 《Clinical microbiology and infection》2006,12(3):293-296
Rapid, accurate and inexpensive methods are essential to detect drug-resistant Mycobacterium tuberculosis and allow timely application of effective treatment and precautions to prevent transmission. The proportion method, the MTT and Alamar Blue redox methods, and the D29 mycobacteriophage assay, were compared for their ability to detect resistance to isoniazid and rifampicin. When tested against a panel of known M. tuberculosis strains, the redox methods and the D29 assay showed good sensitivity and specificity compared to the proportion method, suggesting that they could be useful alternatives for identifying multidrug resistance in M. tuberculosis. 相似文献
64.
目的 观察在腕关节尺桡偏运动时,舟月骨间韧带(scapholunate interosseous ligament,SLIL)及其各亚区分级切断后对舟骨与月骨三维运动的影响,从亚区水平对SLIL在舟月骨三维运动中的作用进行研究.方法 取12例新鲜冰冻成人上肢标本(左、右侧各6例),共分为正常对照组、断SLIL近侧组、断SLIL近+背侧组、断SLIL近+掌侧组、SLIL全断组(每组6例).采用三维激光扫描及图像重建技术,测定在腕关节尺桡偏时舟骨与月骨的三维运动数据,并进行统计学处理.结果 在正常腕关节做尺桡偏运动时,舟、月骨同时也做尺桡偏运动,但还伴有明显的屈伸方向上的运动;与此同时,舟、月骨还做一定的旋前、旋后活动.在切断近+掌和近+背侧亚区组,舟月骨的活动受到影响.全切断SLIL会导致舟骨掌屈度增加,月骨掌屈活动减弱.结论 采用三维激光扫描及图像重建技术可准确测定腕舟月骨的三维活动度,从SLIL亚区水平上进行的研究表明,部分或全部切断SLIL后会对舟月骨的掌屈程度产生明显影响,但SLIL近侧亚区在控制舟、月骨的活动上不起主要作用. 相似文献
65.
Tobias Forschner Stefan Buchholtz Eggert Stockfleth 《Journal der Deutschen Dermatologischen Gesellschaft》2007,5(6):467-475
Vitiligo is a skin disease with a worldwide prevalence ranging from 0.5% to 4%. Conservative therapies include photochemotherapy, phototherapy with UVB radiation (broadband UVB 290–320 nm, narrow band UVB 311 nm), systemic steroids and pseudocatalase. Modern therapeutic options include treatment with topical immunomodulators (tacrolimus, pimecrolimus), analogues of vitamin D3, excimer laser and surgery/transplantation. Our analysis compares these therapies for vitiligo and the evidence levels supporting their effectiveness. Conclusions: The face and neck respond best to all therapeutic approaches, while the acral areas are least responsive. For generalized vitiligo, phototherapy with UVB radiation is most effective with the fewest side effects; PUVA is the second best choice.Topical corticosteroids are the preferred drugs for localized vitiligo. They may be replaced by topical immunomodulators which display comparable effectiveness and fewer side effects.The effectiveness of vitamin D analogues is controversial with limited data. Surgical therapy can be very successful, but requires an experienced surgeon and is very demanding of time and facilities, thus limiting its widespread use. L-phenylalanine therapy appears effective on the face but enjoys neither widespread use nor extensive data support. No single therapy for vitiligo can be regarded as the most effective as the success of each treatment modality depends on the type and location of vitiligo. 相似文献
66.
目的为临床应用锁骨上神经营养血管皮瓣提供解剖学依据。方法在36侧经股动脉插管灌注红色乳胶溶液的成人尸体标本上,对锁骨上神经营养血管的横径、长度及穿深筋膜点的位置,进行了观测,并在标本上模拟手术设计。结果锁骨上神经营养血管包括颈升动脉肌皮支、颈横动脉颈段皮支、胸廓内动脉穿支、胸肩峰动脉胸肌支与肩峰支皮动脉,其穿深筋膜点外径分别为0.75、1.12、1.36、0.70、0.79mm;且穿深筋膜点位置相对恒定,节段性地分布于锁骨上神经,为整段皮神经提供营养。结论以上述节段动脉为蒂,设计锁骨上神经营养血管皮瓣。 相似文献
67.
Brett W. Cox M.D. Kathleen C. Horst M.D. Sherri Thornton C.M.D. Frederick M. Dirbas M.D. 《Medical Dosimetry》2007,32(4):254-262
The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings. 相似文献
68.
Background: The Farnsworth D15 test is designed to categorise colour vision deficiency as severe or moderate. The level of difficulty of the test was set so that those who passed it should be able to recognise surface colour codes, such as those used for electrical wiring. The test is widely used to provide advice to patients with abnormal colour vision and is often used for occupational selection when reliable recognition of surface colour codes is required. However, there has been only one previous study of the correlation between performance at the D15 test and the naming of surface colour codes and there has been no study of whether a person who passes the D15 can reliably name surface colours. Methods: One hundred and two people aged 11 to 65 years with abnormal colour vision were recruited from consecutively presenting optometric patients and were asked to name the colours of fabric, paint and cotton thread samples. There were 10 colours in each class of material and the samples were presented in a large (five to 10 degree angular subtense) and small size (2.5 deg and a single thread). The errors made were compared to those made by an age‐matched control group of equal size with normal colour vision. Results: The correlations between the Farnsworth D15 colour confusion index and colour naming errors were 0.62 for the large stimuli and 0.73 for the small stimuli. Its sensitivity and specificity identifymg those who made more errors than the worst performing colour normal person were 0.80 and 0.69 (large stimuli) and 0.75 and 0.71 (small stimuli). A Nagel anomaloscope range of less than 35 scale units provides essentially the same sensitivity and specificity. Conclusions: About 40 per cent of those with abnormal colour vision can name the main colours correctly under good visibility conditions. The D15 test is an imperfect predictor of those who can name surface colour codes correctly but it does provide useful information for general counselling. It is not suitable as a single test for occupational selection because it will pass 20 per cent who cannot name surface colours correctly and fail 30 per cent who can. In occupations in which recognition of surface colour codes is of critical importance, it may be best not to select people with abnormal colour vision because of the lack of a colour vision test that is a perfect predictor of the ability to recognise surface colours. 相似文献
69.
70.