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101.
乳腺癌患者癌胚抗原检测的临床意义   总被引:1,自引:0,他引:1  
目的探讨癌胚抗原(CEA)检测在乳腺癌诊断和判断预后中的作用。方法应用免疫组化方法检测64例乳腺癌、37例正常及良性病变中癌胚抗原的表达。结果乳腺癌中癌胚抗原的阳性率(68.8%)明显高于正常对照组(16.2%),有显著性差异(P<0.05)。乳腺癌有淋巴结转移的癌胚抗原的阳性率(81.3%),略高于乳腺癌没有淋巴结转移的癌胚抗原的阳性率(56.3%),无显著性差异。结论癌胚抗原的检测有助于乳腺癌的诊断,癌胚抗原可能是判断乳腺癌预后的重要指标。  相似文献   
102.
目的构建大鼠维生素D受体(VDR)蛋白表达载体,测定并分析遗传性高钙尿性结石(GHS)大鼠VDRcDNA序列。方法采用半定量逆转录-聚合酶链反应(RT—PCR)方法扩增含VDR蛋白编码基因序列,将扩增产物克隆至真核表达载体pcDNA3.1/Zero(+),对5只GHS大鼠和4只正常尿钙对照(NC)大鼠十二指肠VDRcDNA序列进行测序分析。结果琼脂糖凝胶电泳示PCR扩增产物碱基数目与目的片段大小一致。对重组质粒的分析表明,插入片段的序列与发表的VDR基因编码序列相同。5只GHS鼠和4只NC鼠肠VDR cDNA序列均有3个相同的位点不同于已公布的大鼠肠VDR cDNA序列:在256bp位点:C取代G;569bp位点:G代替A;1658位点:A替代G。另外,GHS鼠在1795bp位点发生改变,G取代A,而NC鼠则无改变。结论大鼠维生素D受体蛋白编码序列被成功地克隆至表达载pcDNA3.1/Zero(+)上。GHS大鼠基因编码区的序列组成同NC大鼠相一致,但GHS鼠1795bp位点的碱基改变未见于NC鼠。  相似文献   
103.
Audiogenic seizures can be induced in DBA/2J mice following intense auditory stimulation. A number of neurotransmitters, including 5-hydroxytryptamine (5-HT), are believed to be involved in mediating this effect since it has been shown previously that depletion of 5-HT or blockade of 5-HT receptors protects DBA/2J mice from these audiogenic seizures. The present study was undertaken to determine whether antagonism of the newly identified 5-HT7 receptor may protect DBA/2J mice from audiogenic seizures by attempting to correlate in vivo potency of compounds with their affinity at the 5-HT7 receptor. All compounds used in the correlation were shown to be antagonists at the 5-HT7 receptor and a statistically significant correlation was observed between 5-HT7 affinity and doses for half-maximal response (ED50) for protection of DBA/2J mice from sound-induced seizures (r = 0.80; P < 0.05). No significant correlation was observed between in vivo activity and affinity at either 5-HT1A, 5-HT2A or 5-HT2C receptors. It is also unlikely that interactions between the 5-ht5 receptor will protect DBA/2J mice from audiogenic seizures since metergoline and mesulergine which are both active in this in vivo model have no affinity for the 5-ht5 receptor. There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant. Furthermore, the 5-HT1A receptor antagonist WAY 100135 did not protect DBA/2J mice from audiogenic seizures at doses that antagonise 5-HT1A receptor-mediated effects in mice. These data suggest that antagonism of 5-HT7 receptors may protect against audiogenic seizures in DBA/2J mice although a definitive conclusion must await studies with selective 5-HT7 antagonists. Received: 20 March 1997 / Accepted: 10 August 1997  相似文献   
104.
The state of pregnancy is an immunological enigma during which the body must prevent rejection of the antigenically foreign fetus while at the same time maintain sufficient maternal host defense mechanisms to combat infection. Although most studies on the immunology of pregnancy focus on immune suppression, several studies have shown an increase in nonspecific host defense, which is postulated to be a compensatory mechanism for decreased specific immunity during pregnancy. Studies in this laboratory have shown that monocyte surface FcγRI (CD64) and FcγRII (CD32) expression progressively increase throughout pregnancy, while surface MHC class II expression remains unchanged. Functional studies revealed that the number of phagocytic monocytes which could be isolated from pregnant women was increased. These cells exhibited an increased capacity to ingest IgG-opsonized human erythrocytes. This study shows for the first time that monocyte surface FcγR expression and FcγR-mediated functions are increased during pregnancy. These results support the hypothesis that nonspecific immunity as represented by FcγR expression and function is increased during pregnancy.  相似文献   
105.
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060)  相似文献   
106.
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas.  相似文献   
107.
静脉预注H1,H2受体阻滞药对减轻鱼精蛋白副作用的研究   总被引:3,自引:0,他引:3  
将30例ASD、VSD患者随机分为对照与预防用药两组,对比观察H1、H2受体阻滞药苯海拉明、西米替丁对减轻鱼精蛋白副作用的效果和应用鱼精蛋白后补体C3、C4、CH50浓度变化。结果发现预防用药组血液动力学变化明显小于对照组,两组之间差异显著(P<0.01)。应用鱼精蛋白后C3、C4、CH50均下降,与用药前相比差异显著(P<0.01)。提示鱼精蛋白中和肝素可引起补体激活、组胺释放,H1、H2受体阻滞药能够减轻鱼精蛋白引起的血压下降。  相似文献   
108.
The synthesis of nerve growth factor (NGF) by the hippocampus raises the possibility that NGF may play a role in the regulation of the hypothalamic-pituitary-adrenal axis (HPAA). Subchronic cold stress has been shown to activate the HPAA in a mild noninvasive manner, to stimulate serum glucocorticoid levels, and to perturb NGF binding in hippocampus and basal forebrain. One or repeated episodes of cold stress increased NGF mRNA levels in the hippocampus and p75NGFR mRNA levels in the basal forebrain. These changes were not due to elevated serum glucocorticoid levels since treatment with exogenous corticosterone had no effect on NGF and p75NGFR mRNA levels. Adrenalectomy did not prevent the stress induced increases in NGF and p75NGFR mRNA. © 1993 Wiley-Liss, Inc.  相似文献   
109.
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr).  相似文献   
110.
Nociceptin (Orphanin FQ) is a newly discovered endogenous heptadecapeptide substrate for the opioid-receptor-like 1 receptor, a G protein coupled receptor that bears striking amino acid sequence homology to opiate receptors. In rats, intrathecal (i.t.) administration of nociceptin is without effect on basal thresholds for responsiveness to electric foot shock. However, during either late gestation or its hormonal simulation, when nociceptive thresholds are elevated by approximately 70%, i.t. nociceptin substantially attenuates jump thresholds in a dose-dependent fashion. This hypoalgesic effect of nociceptin is not limited to attenuating the gestational or sex steroid-induced increment in pain thresholds. Following the highest i.t. dose of nociceptin employed (20 nmol), the gestational or sex steroid-induced increment in jump thresholds is not only abolished but a significant hyperalgesia is observed. These results underscore the importance of the hormonal milieu to nociceptin hypoalgesic sensitivity. The potential contribution of spinal nociceptive pathways that utilize nociceptin to the etiology of extraordinary painful pregnancy and labor should not be ignored.  相似文献   
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