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31.
目的:探讨HPV16、18-DNA亚型检测对宫颈癌的早期诊断价值。方法:84例标本分别采用FQ-PCR法和巴氏染色法。结果:HPV16、18-DNA阳性19例,阳性率为22.6%,19例HPV16、18-DNA阳性分泌物中4例为CIN2或以上。HPV16、18亚型是导致80%宫颈上皮瘤样病变的主要因素。讨论:HPV16、18-DNA检测可作为宫颈癌早期诊断的有效手段,能准确地预测宫颈癌发生可能性。 相似文献
32.
目的探讨通用引物聚合酶链反应-单链构象多态性(PCR-SSCP)技术在细菌检测中的应用.方法选取9种常见的细菌,采用通用引物对细菌的16SrRNA基因进行PCR扩增,产物进行单链构象多态性分析,并以标准菌株为对照.结果一对引物扩增产物SSCP图谱各细菌之间难以区别;两对引物扩增产物SSCP图谱条带数目、相对迁移率及条带之间的间距存在明显,可相互区别;3种细菌的标准菌株和临床菌株的SSCP图谱完全一致.结论采用针对16SrRNA的通用引物PCR-SSCP技术以标准菌株为对照可方便快捷地检测细菌. 相似文献
33.
A. Bogaards PhD H.J.C.M. Sterenborg B.C. Wilson 《Photodiagnosis and Photodynamic Therapy》2007,4(3):170-178
With the advent of molecular-targeted fluorescent markers, there is a renewed interest in fluorescence quantification methods that are based on continuous wave excitation and multi-spectral image acquisition. However, little is known about their in vivo quantification performance. We reviewed the performance of five selected methods by analytically describing these and varying input parameters of irradiance, excitation geometry, collection efficiency, autofluorescence, melanin content, blood volume, blood oxygenation and tissue scattering using optical properties representing those for human skin. We identified one method that corrects for variations in all parameters. This requires image acquisition before and after marker administration, under identical geometry. Hence, it is suited for applications where the site of interest can be relocated (e.g. anaesthetized animals and dermatology). For applications where relocation is not possible, we identified a second method where the uncertainty in the fluorescence signal was ±20%. Hence, use of these methods can substantially aid in vivo fluorescence quantification compared to use of the raw fluorescence signal, as this changed by more than 3 orders of magnitude. Since these methods can be computed in real-time, they are of particular interest for applications where direct feedback is critical, as diagnostic screening or image-guided surgery. 相似文献
34.
35.
目的:探讨胰腺癌与癌旁组织中p16基因启动子区异常甲基化的改变及其蛋白表达的特点,以及其与胰腺癌发生发展的关系。方法:分别采用免疫组化SP法及甲基化特异PCR(MSP)检测46例人胰腺癌和癌旁组织中p16基因表达及其甲基化的水平,并结合临床资料进行分析。结果:胰腺癌中p16蛋白表达率为41.3%(19/46),而癌旁组织表达率为95.7%(44/46),两者有差异显著性(P<0.01)。p16蛋白阳性的19例胰腺癌标本中均未检出基因甲基化;p16蛋白缺失的27例标本中有18例检出基因甲基化,甲基化率为39.1%。p16基因甲基化与蛋白缺失有明显关系(P<0.05)。p16基因表达及其启动子区甲基化的发生率与胰腺癌的大小,患者性别﹑年龄的差异无显著意义(P>0.05),但与组织分化程度﹑淋巴结转移﹑PTNM分期有显著意义(P<0.05)。结论:p16基因启动子的异常甲基化可影响p16蛋白的表达,它们与胰腺癌的发生发展有关;p16甲基化和蛋白表达可能成为胰腺癌诊断及预后的候选标志物之一。 相似文献
36.
Manuel Sosa P. Saavedra J. del Pino-Montes J. Alegre R. Pérez-Cano G. Martínez Díaz Guerra M. Díaz-Curiel C. Valero M. Muñoz-Torres A. Torrijos J. Mosquera C. Gómez-Alonso GIUMO Study Group 《Journal of clinical densitometry》2005,8(4):430-435
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height. 相似文献
37.
Activity of succinic dehydrogenase(SDH)and acid phosphatase(AcPase)of effector-target cells during the process of LAK cells killing HR8348 cells was estimated by enzyme cyto-chemistry technique.SHD positive granules and AePase gray level were assayed with MIAS-300image analyser.The results showed:(1)After cocultivation of effector and target cells for vari-ous times,the activity of AcPase of HR8348 cells was apparently higher than that of the controlgroup,and it increased following prolonged coincubation.SDH activity of target cells increasedmarkedly within 30 and 60 rain cocultivation,but became low after 90 min treatment.(2)Ac-Pase content within LAK cells at 60,90,120,180 and 240 rain cocultivation was significantlyhigher than that of control group(P<0.01).The phenomenon of high AcPase and SDH activitywithin effector-target cells indicates that the function of the two types of cells was in an activestate.At the early stage of effector-target combining,the increase of SDH with HR8348 cellsmay be related to defensive function of the target cells.Higher AcPase activity of target cells in-dicates the activation of lysosomal enzyme which serves as the material basis for autolysis of thecells. 相似文献
38.
39.
Kohei Hara MD PhD Shigeru Kohno MD PhD Hironobu Koga MD PhD 《Journal of infection and chemotherapy》1996,1(3):166-176
Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such
as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have
many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can
easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures
can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those
with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated
patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic
efficacy.
Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various
problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However,
the importance of accurately determining the causative organism in respiratory infections should be recognized as the most
important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment
of respiratory infections in a wide variety of patients. 相似文献
40.
P53、P16、Bcl-2基因及产物在原发性肺癌中的表达及其临床病理意义 总被引:3,自引:0,他引:3
目的 :探讨原发性肺癌 Mtp5 3、p16、Bcl- 2的异常表达与肺癌发生、发展的关系 ,以及它们之间的调控关系。 方法 :用免疫组化技术检测 (L SAB) 114例原发性肺癌组织中 p5 3、p16、Bcl- 2的表达。并用 PCR技术对 6 2例 p16蛋白丢失的肺癌组织中 p16外显子 2 (p16 E2 )的缺失进行分析。 结果:p5 3蛋白异常表达与肺癌组织学类型、分化程度无关 (P >0 .0 5 ) ,但与淋巴结转移情况有关 (P >0 .0 5 )。 p16蛋白阳性表达率与肺癌的组织学类型无关 ,但是其表达水平与非小细胞肺癌 (NSCL C)的细胞分化程度和淋巴结转移密切相关 (P <0 .0 5 )。 NSCL C中 p16E2的缺失率为 45 .2 %,其缺失水平随淋巴结转移和组织学分级的升高而升高 (P <0 .0 5 )。 SCL C(小细胞肺癌 )和正常肺组织中无 p16 E2的缺失。 Bcl- 2在小细胞肺癌中阳性率 6 2 .2 %显著高于 Sq Ca(鳞癌 )的 2 5 %和 Ad Ca(腺癌 )的 9.1%(P <0 .0 5 ) ,与细胞分化程度和淋巴结转移情况无关。另外 ,p5 3与 p16蛋白之间存在调控关系。 结论 :(1) p16、p5 3、Bcl- 2的异常参与肺癌的发生、发展过程。 (2 ) p16基因及产物的异常表达与 NSCL C的组织学分级和淋巴结转移相关 ,可能参与 NSCL C的发生、发展和转移过程。 (3) Bcl- 2反映 SCL C的分之生物学行为和临床 相似文献