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951.
黄珊珊 《国外医学:妇产科学分册》2009,36(1):56-59
丝裂原活化蛋白激酶(MAPK)通路目前已鉴定出4条[细胞外信号调节激酶(ERK)1,2、P38丝裂原活化蛋白激酶(P38)、c-Jun氨基末端激酶(JNK)和ERK5],其中ERK1/2通路可被多种刺激活化,通过调控细胞周期,抑制细胞凋亡。促进细胞增殖、迁移和侵袭等而与肿瘤的发生发展密切相关。许多子宫内膜癌相关因素通过MAPK/ERK通路起作用。雌激素可以通过非基因组转录效应迅速激活MAPK通路促进子宫内膜的的发生发展。综述MAPK/ERK信号通路的研究进展,重点论述MAPK/ERK信号通路与子宫内膜癌的关系及分子机制,以及MAPK/ERK通路抑制剂在肿瘤防治方面的临床应用前景。 相似文献
952.
目的:通过检测双链RNA依赖的蛋白激酶(PKR)、人乳头瘤病毒(HPV)在宫颈病变组织中的表达,探讨PICR在宫颈病变发生发展中的意义及可能机制。方法:选择临床病历资料和病理资料完整的宫颈癌患者共37例、同期宫颈上皮内瘤样病变(CIN)Ⅰ-Ⅲ患者56例为研究对象,因子宫肌瘤等良性病变切除子宫的正常宫颈组织30例为对照。采用免疫组织化学SABC法检测PICR及HPV16/18E6的表达。分析二者与宫颈病变发生发展的关系。结果:宫颈癌组织中PKR表达阳性率为54.1%,高于CINⅢ。CINⅠ-Ⅱ组和正常宫颈组,差异有统计学意义(P〈O.05);在宫颈癌组中PICR表达与HPV16/18E6表达存在负相关(r=-0.554,P〈0.05);在CINⅢ组中PKR表达与HPV16/18E6表达存在正相关(r=0.480,P=0.032)。结论:PKR的异常表达在CINⅢ向宫颈癌发展过程中可能发挥主要作用.此外SABC法测定PKR和E6的表达有可能成为筛选子宫颈癌的早期指标。 相似文献
953.
目的:探讨宫颈病变组织HPV16/18感染对蛋白激酶R(PKR)激活的影响及两者在宫颈癌形成、演进过程中的作用和对宫颈癌患者预后的影响。方法:用免疫组化SP法检测HPV16/18型E6蛋白(E6)、PKR、磷酸化型PKR(p-PKR)在63例宫颈癌、114例宫颈上皮内瘤样病变(CINⅠ~Ⅲ)、15例正常宫颈组织的表达。结果:E6蛋白与PKR在各组的阳性表达率与宫颈病变级别呈正相关(P<0.05,P<0.05),E6蛋白与PKR在各组的阳性表达率呈正相关(P<0.05);宫颈癌组PKR阳性表达率明显高于p-PKR(P<0.01);E6、PKR阳性表达率与肿瘤大小有关(P<0.05,P<0.05);宫颈癌患者病情进展与临床分期显著相关(P<0.01),病情进展与E6、p-PKR阳性表达率相关(P<0.05,P<0.05)。结论:HPV16/18感染可阻碍PKR激活,突破机体防御HPV16/18感染的机制,在宫颈癌的发生及演进过程中可能起了重要作用,对宫颈癌患者预后不利;p-PKR能抑制宫颈癌患者病情进展,可能改善其预后。 相似文献
954.
目的:研究睾丸局部感染后支持细胞免疫调节功能与锌指蛋白265(zinc finger protein265,ZNF265)的变化情况。方法:以溶脲脲原体(Ureaplasma urealyticum,UU)体内感染支持细胞后,分别在感染1、2、3周时间段运用RT-PCR、免疫组化和流式细胞术(FCM)方法比较感染组与对照组间ZNF265、IL-1α、IL-6、TGF-β和FasL的mRNA及蛋白水平的表达变化情况。结果:与对照组相比,体内感染处理后2周后支持细胞的ZNF-265表达下降,3周后又升高;TGF-β和FasL从感染2周开始表达上升,一直至3周仍处于上升趋势;感染2周IL-1α和IL-6表达分别上升;3周后则分别下降。结论:ZNF265在支持细胞被UU感染后会产生表达变化。 相似文献
955.
Objective To explore the relationship between total bile acid(TBA)concentration and fetal pulmonary surfactant in intrahepatic cholestasis of pregnancy(ICP).Methods Fifry five patients with ICP(ICP group)who received cesarean section from April 2008 to February 2010 in Second Xiangya Hospital,Central South University,were recruited.The general conditions of the neonates within 7 days after birth in ICP group were recorded.Those with fetal distress,neonatal asphyxia,or neonatal respiratory distress syndrome were referred as pathological neonates, others were referred as normal neonates. Over the same period, 23 healthy gravidas were recruited as control group. Enzymatic method was used to detect the TBA concentrations in maternal blood, cord blood and amniotic fluid. ELISA was employed to measure the urfactant protein A (SP-A) concentration in cord blood. High performance liquid chromatography system was used to detect the concentrations of phesphatidylcholine (PC),phosphatidylinositol (PI),lysophosphatidylcholine ( LPC), and sphingomyelin(SM) in amniotic fluid. Results ( 1 ) The concentrations of TBA in maternal blood, cord blood and amniotic fluid were ( 30. 1 ± 7.9 ), (9. 3± 3. 3 ) and (4. 4 ± 1.5 ) mmol/L in ICP group, (4. 8 ± 2. 2), (4. 9 ± 0. 9) and ( 1.4 v 1.1 ) mmol/L in control group, respectively. The differences between the two groups were significant ( P < 0. 05 ). ( 2 ) The SP-A concentration in cord blood in ICP group was ( 29. 5 ± 6. 4 ) μg/L, significantly higher than that in control group, which was ( 22. 6 ± 7. 4 )μg/L ( P< 0. 05 ). ( 3 ) There were 20 pathological neonates and 35 normal neonates in ICP group. In pathological neonates, the concentrations of TBA and SP-A in cord blood were (10.9 ± 2.2) mmol/L,(37.0 ± 5.9 ) μg/L, respectively; and were ( 8.0 ± 2. 8 ) mmol/L, ( 26. 7 ± 4. 8 ) μg/L in normal neonates. The differences were significant (P< 0. 05 ). (4) There was a positive correlation between TBA concentration in cord blood and in maternal blood ( r1 = 0. 706, P<0. 05 ). The TBA concentration in cord blood was positively correlated with SP-A concentration as well ( r3 = 0. 494,P < 0. 05 ). (5) The PC and PI concentrations in amniotic fluid were (65.4 ± 7.2) mg/L and ( 3. 8 ± 0. 6 ) mg/L in ICP group, ( 69. 7 ±3.7) mg/L and (4. 3 ± 0. 7 ) mg/L in control group, respectively. The differences were significant (P <0. 05 ). The concentration of LPC in amniotic fluid in ICP group was (4. 8 ±0. 9) mg/L, significantly higher than that in control group (P<0. 05), which was (4. 2 ±0. 6) mg/L. The concentration of SM in amniotic fluid was (3.5±0. 8) mg/L in ICP group, (4. 0 ± 0. 5 ) mg/L in control group, with no significant difference ( P>0. 05 ). (6) The ratio of PC/LPC in ICP group ( 14. 2± 3. 2 ) was significantly lower than that in control group ( 16. 9 ± 2. 5 ) ( P< 0. 05 ). ( 7 ) The TBA concentration in cord blood was negatively correlated with PC and PI concentrations (r1 = -0. 561, r2 = -0. 407, P < 0. 05 ), and had no correlation with LPC concentration (r3 = 0. 260, P> 0. 05). Conclusions ( 1 ) The fetal TBA concentrations in both cord blood and amniotic fluid of patients with ICP was higher than those of healthy gravidas, they were also positively correlated with maternal TBA concentration. (2) ICP resulted in the change of fetal pulmonary surfactant and this change was associated with TBA concentrations in both cord blood and amniotic fluid. 相似文献
956.
957.
V. V. Yasnetsov A. N. Gromov N. M. Kiseleva D. Yu. Rusakov S. G. Batrakov A. V. Evstratov V. S. Shashkov 《Bulletin of experimental biology and medicine》1994,117(4):443-444
Cat and rat experiments show that the protein fraction isolated from blood serum of the Greenland seal has a protective activity
against motion sickness. This activity is comparable to that of the classical vestibuloprotector scopolamine and is greater
than that of diprazine. Radioligand assay of the receptor binding showed that the serum protein fraction has the highest affinity
for α2-adrenoceptors, μ-opioid, and benzodiazepine receptors.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol 117, N
o
4, pp. 444–445, April, 1994 相似文献
958.
OBJECTIVE: This study was undertaken to assess the left ventricular mass (LV Mass) and systolic and diastolic functions of the left ventricle in children with protein energy malnutrition (PEM). METHODOLOGY: Thirty children, aged between 2 months and 2 years with PEM (four kwashiorkor, seven marasmic- kwashiorkor, 19 marasmus), and 17 healthy, age-matched children, using Doppler echocardiography were studied. RESULTS: The mean LV Mass in the patients was lower than that in the controls (14.5 +/- 5.2 vs 19.8 +/- 4.7 g, P < 0.05). However, the LV Mass/body surface area was not different in the patients with PEM and in the control group (52 +/- 9.2 vs 53.9 +/- 8.2g/m(2), P > 0.05), indicating that LV Mass was reduced in proportion to decrease in body size in malnutrition. Left ventricular septal and posterior wall thickness in PEM were also lower than that in the controls, and the most significant reduction in the LV Mass, septal and posterior wall thickness were found in the kwashiorkor group. Cardiac output was reduced in proportion to decrease in body size in the patient group (1.6 +/- 0.5 vs 2.1 +/- 0.8 L/min, P < 0.05), therefore cardiac index was not significantly different between the patients and the control subjects (5.9 +/- 1.4 vs 5.7 +/- 1.6 L/min/m(2), P > 0.05). Systolic function indices including ejection fraction, fractional shortening, and diastolic function indices were not significantly different in the groups. CONCLUSIONS: We demonstrated that LV Mass and cardiac output were reduced in proportion to decrease in body size in patients with PEM, and LV systolic and diastolic functions were preserved in atrophic hearts. 相似文献
959.
Tau protein concentrations in cerebrospinal fluid of patients with multiple sclerosis 总被引:2,自引:0,他引:2
Jiménez-Jiménez FJ Zurdo JM Hernanz A Medina-Acebrón S de Bustos F Barcenilla B Sayed Y Ayuso-Peralta L 《Acta neurologica Scandinavica》2002,106(6):351-354
FUNDAMENTALS AND OBJECTIVE: Multiple sclerosis (MS) is the prototype of demyelinating disease, but recently, it has been shown that the existence of axonal lesions contribute to irreversible central nervous system damage in this disease. Tau proteins are considered to be important for maintaining the stability of axonal microtubules involved in the mediation of fast axonal transport of synaptic constituents. There have been reports of increased cerebrospinal fluid (CSF) tau concentrations in patients with MS, and it has been suggested that this could be a marker of axonal damage. The objective of the present study was to elucidate whether CSF tau levels could be a marker of MS activity. PATIENT AND METHODS: We measured tau concentrations in the CSF of 20 patients with MS (nine in the first, seven in the second, one in the fourth exacerbation, and three patients with chronic progressive course) and 32 age- and sex-matched controls, using a specific enzyme-linked immunosorbent assay method. RESULTS: The CSF tau concentrations of patients with MS did not differ from those of controls, and they were not correlated with age at onset and duration of the disease. CONCLUSION: CSF tau concentrations are not a marker of MS activity. 相似文献
960.
Use of diffusion weighted MRI to predict the occurrence and severity of hemorrhagic transformation in a rabbit model of embolic stroke 总被引:8,自引:0,他引:8
Alpha-synuclein is a brain presynaptic protein that is linked to familiar early onset Parkinson's disease and it is also a major component of Lewy bodies in sporadic Parkinson's disease and other neurodegenerative disorders. Alpha-synuclein expression increases in substantia nigra of both MPTP-treated rodents and non-human primates, used as animal models of parkinsonism. Here we describe an increase in alpha-synuclein expression in a human neuroblastoma cell line, SH-SY5Y, caused by 5-100 microM MPP+, the active metabolite of MPTP, which induces apoptosis in SH-SY5Y cells after a 4-day treatment. We also analysed the activation of the MAPK family, which is involved in several cellular responses to toxins and stressing conditions. Parallel to the increase in alpha-synuclein expression we observed activation of MEK1,2 and ERK/MAPK but not of SAPK/JNK or p38 kinase. The inhibition of the ERK/MAPK pathway with U0126, however, did not affect the increase in alpha-synuclein. The highest increase in alpha-synuclein (more than threefold) in 4-day cultures was found in adherent cells treated with low concentrations of MPP+ (5 microM). Inhibition of ERK/MAPK reduced the damage caused by MPP+. We suggest that alpha-synuclein increase and ERK/MAPK activation have a prominent role in the cell mechanisms of rescue and damage, respectively, after MPP+ -treatment. 相似文献