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81.
目的:建立一套测定单个细胞内蛋白含量的新方法。方法:纯化培养乳鼠雪旺氏细胞,施加实验因素,通过间接免疫荧光法标记细胞内NGF蛋白,而后用流式细胞仪(适用于细胞悬液样品)或粘附细胞仪(适用于粘附细胞样品)进行测定。结果:流式细胞仪及粘附细胞仪均可得到每一实验组的精确测定结果,并能进行统计分析,提供统计图表和各种数据。结论:应用流式细胞仪或粘附细胞仪可对单个雪旺氏细胞内的NGF含量进行定量研究 相似文献
82.
Constrained optimization recently has been implemented in the LISREL software package, allowing formulation of parent-offspring transmission models in a simple and efficient manner. A reverse path model of parental transmission is described within the LISREL framework for application to twin and/or adoptive family data. The model incorporates genetic and environmental parameter constraints arising from assortative mating and cultural transmission. An illustration of the LISREL model is given using measures obtained from twins and parents involving fear of social criticism. 相似文献
83.
Makino S Miyamoto T Nakajima S Kabe J Baba M Mikawa H Furusho M Fukuda K Nakagawa T Naitou H 《Allergy》2000,55(2):135-140
BACKGROUND: In Japan in 1993, the Japanese Society of Allergology (JSA) developed guidelines for diagnosis and management of asthma (JGL), which were based on the concept that asthma is a chronic inflammatory disorder of the airway. METHODS: This survey study was intended to investigate the recognition and utilization of JGL among physicians who had treated asthma. The survey comprised two methods: a quantitative mail survey and a qualitative door-to-door survey conducted by trained interviewers. RESULTS: In the mail survey, a total of 1028 physicians responded; 552 members of the JSA and 476 nonmembers. Ninety-four percent of JSA members were aware of adult asthma management guidelines, while 53% of nonmembers were aware of them. Although approximately half of the physicians, both members and nonmembers, found differences between the asthma management policies in JGL and their previous policies, most of them utilized JGL once they read it. In the qualitative door-to-door survey, 80-90% of physicians evaluated JGL as good after they read it. CONCLUSIONS: JGL was recognized and utilized by most JSA members, but only half of nonmember physicians were aware of JGL, although they utilized JGL after they read it. Further action to implement JGL among nonspecialist physicians is needed to improve management of asthma. 相似文献
84.
85.
Liefeldt L Plentz A Klempa B Kershaw O Endres AS Raab U Neumayer HH Meisel H Modrow S 《Journal of medical virology》2005,75(1):161-169
Organ transplant recipients infected with parvovirus B19 frequently develop persistent viremia associated with chronic anemia and pure red cell aplasia. In this study, a male renal transplant recipient who had been infected with parvovirus B19/genotype 2 after renal transplantation at the age of 34 years is described. The patient was repeatedly treated with high dose intravenous immunoglobulin (IVIG) that resulted in the resolvement of symptoms but not in virus eradication. During an observation period of 33 months after transplantation three phases associated with high parvovirus B19 viremia were observed. Both the first and the second viremic phases were combined with severe anemia. Parvovirus B19 specific IgM-antibodies were initially detected at the beginning of the second phase in continually rising concentrations. Initially eradication of the virus by immunoglobulin therapy was reported after the first viremic phase [Liefeldt et al. (2002): Nephrol Dial Transplant 17:1840-1842]. Retrospectively this statement has to be corrected. It was based on the use of a qualitative PCR assay specific for parvovirus B19 genotype 1 associated with reduced sensitivity for detection of genotype 2. After sequence analysis of the viral DNA and adjustment of a real-time PCR assay (TaqMan) for quantitative detection of all three B19 virus genotypes analysis of consecutive serum samples allowed the demonstration of long lasting phases with reduced viral loads following IVIG-treatment. These results demonstrate that IVIG treatment of parvovirus B19-triggered anemia in transplant recipients offers an opportunity to resolve symptoms, but does not guarantee eradication of the virus. Since reactivation of parvovirus B19 infection can result in high virus load associated with the recurrence of symptoms repeated screening for viral DNA is recommended using the TaqMan system established for quantitative detection of all three genotypes of parvovirus B19. 相似文献
86.
Kontiokari T Renko M Kaijalainen T Kuisma L Leinonen M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(11):734-738
It is not known how well nasopharyngeal swab culture represents pneumococcal carriage status. We tested this by comparing swab culture to quantitative culture and quantitative PCR of mucosal tissue in a rat model of pneumococcal carriage. Quantitative culture and quantitative PCR identified significantly more carriers compared to swab culture (differences 15% and 33%, 95% CI 1-28% and 16-47%, p=0.04 and 0.001, respectively). The sensitivity and specificity of swab culture was 75/92% and 63/100% compared to quantitative tissue culture and quantitative PCR, respectively. The quantitative estimates of culture and PCR were very similar (Pearson correlation coefficient 0.79, p<0.001). In conclusion, even a well-controlled swab sampling markedly underestimates pneumococcal carriage rate, and simultaneous use of quantitative culture and PCR increases the number of positive samples by about one third. 相似文献
87.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献
88.
Le Roy-Duflos I 《Behavior genetics》2001,31(1):29-37
The cerebellum is involved in a large set of integrative functions including memory, affect, and motricity. The cerebellar patterns of foliation and their causal relationships with motricity were investigated via a wide genome scan approach and quantitative trait locus (QTL) strategy. QTLs were mapped in an F2 population derived from NZB/B1NJ and C57BL/6By inbred strains of mice for cerebellar fissures in the four vermal lobules (intraculminate, uvula, declival, and intracentral) and for hindpaw slips in a bar crossing test. No linkage was detected for uvula and intracentral fissures. We found five QTLs linked to declival fissure: Cpfd-1q and Cpfd-2q (chromosome 1), Cpfd-3q (chromosome 5), Cpfd-4q (chromosome 9), and Cpfd-5q (chromosome 13). Two QTLs were also mapped for intraculminate fissure Cpfi-1q (chromosome 4) and Cpfi-2q (chromosome 1). Most of the confidence intervals of these QTLs included genes that were previously identified for their implication in the physiological mechanisms underlying cerebellar patterns of foliation. Only one significant QTL was found for the measure of hindpaw coordination (Tne-1q). It was linked with Cpfd-1q and Cpfd-2q on the telomeric part of chromosome 1. 相似文献
89.
目的观察正常孕妇妊娠晚期和妊高征患者血小板参数的变化及临床意义。方法采用日本Sysmex KX-21型血液细胞分析仪分别对正常孕妇(118例)、妊高征患者(59例)及对照组(正常婚检妇女59例)的血液标本进行血小板(PLT)计数、平均血小板体积(MPV)、血小板分布宽度(PDW)的测定。结果妊高征组和正常孕妇组的MPV、PDW显著高于对照组(P〈0.01);妊高征组MPV、PDW明显高于正常孕妇组(P〈0.05);妊高征组的PLT显著低于对照组(P〈0.01)。结论妊高征患者由于血小板消耗和破坏增加,导致血小板减少,MPV、PDW明显增高,因此,检测血小板参数对预测妊高征的发生有一定的参考意义。 相似文献
90.
细胞核形态和DNA指数分析在星形细胞瘤分级诊断中的应用 总被引:1,自引:0,他引:1
目的 探索自动图像分析系统在胶质瘤分级诊断中的应用。方法 采用自行设计组装的MIPS-I型自动图像分析系统对3个级别星形细胞瘤的细胞核形态和DNA指数(倍体)同时进行原位定量测定。结果 在星形细胞瘤分级诊断中,5项反映核形态的参数诊断正确率为56.3%;代表核DNA改变的7项参数诊断正确率为70.8%;综合应用12项参数诊断正确率为75%。结论 细胞核形态和DNA指数分析可作为星形细胞瘤分级诊断的参考指标之一。 相似文献