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71.
Diagnosis of perinatal infection in the newborn is difficult; there may be few clinical signs and current tests are slow or non-specific. Detection of organisms, antigen or specific antibody to common pathogens often requires repeat samples and does not give immediate results. Haematological parameters, although relied upon frequently to diagnose infection in the neonate prior to a positive bacterial isolation, are unreliable and insensitive. Indicators such as an increase in neutrophil band cell counts are highly variable between morphologists. Infection induces the expression of a number of T lymphocyte surface markers, including CD45RA/CD45RO and CD45RO. The use of changed expression of surface markers as a laboratory test for detection of infection in neonates was evaluated. We used multiparameter flow cytometry to detect expression of early (CD45RA/CD45RO) and late (CD45RO) activation markers. In the respective groups of 50 full term (including 25 normal vaginal deliveries and 25 caesarean deliveries) and 30 premature, i.e. < 36 weeks gestation (born by either normal vaginal delivery or caesarean delivery) the CD45RA isoform was brightly expressed on newborn ‘naive’ CD4+ T cells, whereas the CD45RO isoform (including both ‘bright’ and ‘dim’ populations) was present on < 19% of CD4+ T cells from these newborn infants. In a group of 37 infants, tested to evaluate possible effects of non-infective parameters such as respiratory distress and iso-immunization, no significant changes in surface marker expression were found and specificity of the test was confirmed. In 14 neonates with documented sepsis, up-regulation of dual staining CD45RA/CD45RO isoforms on CD4+ T cells was detected early in the infection. In addition, we found that CD45RO expression persisted for several weeks after bacterial infection, and up to several months in viral infection. In conclusion, detection of T cell activation by flow cytometry for the early diagnosis of neonatal infection is an easy test to carry out on small volumes of blood, is inexpensive, and may be a specific indicator of infection. 相似文献
72.
应用门控SPECT测量左心室功能的方法学研究 总被引:2,自引:0,他引:2
目的:试用门控心肌显像测定左室功能并与心血池显像结果比较。材料和方法:61例受检者进行了Tc-99m—MIBI门控心肌显像及心血池显像.结果:门控断层心肌显像的短轴中间部左室功能结果与平衡法心血池显像有良好的相关性(r=0.82)。结论:门控心肌断层显像测定的左室功能结果方法简便可靠.能同时反映心肌直流及左室功能。 相似文献
73.
用辣根过氧化物酶(HRP)微电泳技术研究大鼠前脑和脑干向中央上核(CS)的纤维投射。将HRP输入CS后,观察到缰核、脚间核和被盖背核区有较多的标记细胞,斜角带核、下丘脑核和乳头体核有少量标记细胞。在外侧缰核、脚间核和被盖背核区可见丰富的顺行标记终末。结果表明,前脑的缰核和脑干的脚间核和被盖背核区是CS的主要传入来源,它们之间存在往返的纤维联系。 相似文献
74.
本文报告谷参肠安胶囊大鼠长期毒性试验,结果表明,谷参肠安胶囊对动物的一般状况,体重增长、外周血象、肝肾功能及病理组织学检查等未见明显毒性。 相似文献
75.
The consciousness-restoring method and the conventional method of acupuncture were used for treatment of 92 cases of apoplexy at the convalescent stage. They were randomly divided into 2 groups: the consciousness-restoring group (50 cases), and the conventional group (42 cases). The therapeutic results show that the cure rates in the former and latter groups are 43% and 16.67% respectively. The markedly effective and effective rates in the former group are significantly higher than that in the latter group. The experimental results demonstrate that there is remarkable improvement in the majority of criteria of blood rheology, blood lipid, micro-circulation and thrombus formation in vitro, in the former group, and the degree and extent of improvement are markedly better than the latter group. 相似文献
76.
本文研究了剌玫果对烹饪油烟引起的小鼠骨髓嗜多染红细胞微核率的影响。结果表明,烹饪油烟各实验组的小鼠骨髓嗜多染红细胞微核率明显高于阴性对照组(P〈0.01),且呈现剂量-反应关系,剌玫果明显降低烹饪油烟诱发的微核率。 相似文献
77.
d-宁烯、丹参及姜黄素衍生物对ras基因产物膜结合和细胞间隙信息传导的影响 总被引:3,自引:0,他引:3
目的旨在寻找新型抗肿瘤药物,进一步研究d-宁烯、丹参及姜黄素衍生物的抗肿瘤机理。采用分子生物学方法及划痕标记染料示踪技术,研究了4种人实体瘤起源的细胞系的细胞间隙信息传导(GJIC)、H-ras癌基因表达以及ras癌基因产物(P21ras蛋白)表达状态,并观察了4种天然产物对它们的影响。结果表明,细胞内染料传输功能的丧失与ras基因突变率呈正相关;单萜化合物d-宁烯和酚类化合物丹参衍生物的抗肿瘤作用可能与抑制P21ras蛋白膜结合和增强细胞间隙信息传导功能有关。提示Ras癌基因产物P21ras蛋白膜结合的抑制与细胞间隙信息传导功能的增强有直接关系。 相似文献
78.
本文报道了1984年10月~1985年10月西安市城市居民138例食管癌的病例对照研究。结果表明,吸烟为食管癌发病的危险因素,ORM-H为4.12(95% CI为1.57~6.54)。OR与吸烟量、吸烟年限有显著剂量效应关系。吸烟作为食管癌的可能致病因子其潜隐期为37.19年。饮酒与食管癌的联系不显著(χ2=1.03,P﹥0.05)。作者认为吸烟单独或与其它因素共同作用下可能参与食管的癌变过程。 相似文献
79.
目的:分析损伤性肝外胆管狭窄发生的原因和损伤后狭窄的修复术式选择。方法:损伤性肝外胆管狭窄45例,诊断方法以B超,PTC、ERCP为主,全组分别行胆管空肠吻合术,胆管十二指肠吻合术,肝门胆管整形术等手术治疗。结果:随访36例,末次手术行胆管空肠吻合术33例,优良87.9%。结论:可见性损伤和隐性损伤所致的瘢痕收缩是胆道狭窄的主要原因,损伤性肝外胆管狭窄的治疗方法以胆管空肠Y形吻合术较为理想。 相似文献
80.
Post-transplantation diabetes is better controlled after conversion from prednisone to deflazacort: a prospective trial in renal transplants 总被引:2,自引:0,他引:2
Yu Seun Kim Myoung Soo Kim Soon Il Kim Seung Kil Lim Ho Yung Lee Dae Suk Han Kiil Park 《Transplant international》1997,10(3):197-201
It is well known that long-term use of steroids plays a decisive role in the development of glucose intolerance and diabetes
mellitus (DM). Deflazacort, an oxazoline derivative of prednisolone, has been introduced as a potential substitute for conventional
steroids in order to ameliorate glucose intolerance. We initiated a randomized study of conversion from prednisone to deflazacort
in kidney transplantation (Tx) recipients presenting with pre-Tx or post-Tx DM to ascertain whether or not the switch to deflazacort
would ameliorate the diabetic state. Forty-two recipients in the conversion group were compared with 40 patients on prednisone
(the control group) in a prospective manner. The dose reduction of insulin or oral blood glucose-lowering agents, the adequacy
of glucose control, and the development of side effects were the criteria for evaluating outcome. In the conversion group,
patients were switched to deflazacort at a dose ratio of 6 mg deflazacort to 5 mg prednisone. During the mean follow-up period
of 13.2 months, neither graft dysfunction nor acute rejection developed in the conversion group. Improvement in blood glucose
control in the conversion group was noted. When the conversion group was stratified into pre- or post-Tx DM, promising effects
were clearly evident in the post-Tx DM patients. More than 50 % dose reduction of blood glucose-lowering agents was possible
in 42.3 % of post-Tx DM patients. In conclusion, it was readily possible to control blood glucose better in post-Tx DM recipients
without seriously affecting the immunosuppressive activity after conversion to deflazacort.
Received: 20 August 1996 Received after revision: 25 November 1996 Accepted: 6 December 1996 相似文献