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111.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
112.
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors.  相似文献   
113.
114.
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous.  相似文献   
115.
采用扫描电镜、透射电镜及光镜免疫金银法观察了31例慢性扁桃体炎患者和8例胎儿的扁桃体隐窝上皮结构及其中细胞的分布。电镜观察发现隐窝上皮表面存在三种类型微隐窝开口,其腔内有浸润细胞、异物及细菌。有三种特化上皮细胞(M细胞)覆盖于Ⅲ型微隐窝开口处,其结构与肠道M细胞相似,其数量随扁桃体炎的反复发作而减少。形态表明微隐窝是浸润细胞和外来抗原的出入口。M细胞与抗原的摄取及传递有关。光镜免疫金银法观察证明上皮浸润细胞中多数为OKT_s~+细胞,其中OKT_4~+者又占多数而OKT_s~+细胞较少,这些细胞是隐窝上皮参于免疫应答的结构基础。  相似文献   
116.
核酸原位杂交程序中探针和靶基因的加热变性和杂交为整个程序中最重要的环节,目前国内外最常用的方法是在切片上滴加DNA探针溶液后用盖玻片复盖组织,并加胶泥或其他封固剂封闭玻片四周,变性杂交后需拆除盖玻片,这一操作过程易损坏组织切片或出现干片、脱片。作者针对上述情况,对传统的核酸原位杂交方法中的部分程序加以改良,采用不加盖玻片直接在蒸汽中变性方法,经多次实验证明此方法稳定、可靠、简便,结果满意。  相似文献   
117.
Abstract: Lipid peroxidation, measured by malonyldial-dehyde (MDA) and vitamin E in red blood cells (RBC) and plasma, was investigated in 25 hemodialysis (HD) patients before and after 6 months rhEPO therapy. RBC-MDA was significantly elevated, but plasma MDA was in the reference range. After recombinant human erythro-poietin (rhEPO) treatment, the MDA level was significantly decreased in both compartments. Marked vitamin E deficiency was established in RBC as well as in plasma. rhEPO therapy restored vitamin E levels in both compartments. Our data suggest a possible positive rhEPO-antioxidant effect in HD patients.  相似文献   
118.
Within vivo 1H-MRS resonances of several metabolites were simultaneously measured in cerebral gliomas and adjacent normal brain. 15 patients with inoperable brain gliomas all histologically verified were monitored with 1H-MRS and MRI before and after radiotherapy. 11 patients were evaluable. 1H-MRS technique evolved from single volume measurements to one dimensional and two dimensional 1H spectroscopic imaging. In all patients N-acetyl-aspartate signals were decreased in tumour areas compared to the normal brain hemisphere. No recovery was seen after radiotherapy. Choline signals were increased in tumour margins of high grade gliomas and more diffusely in low grade gliomas. In 5 patients the choline resonance decreased after radiotherapy, accompanied by a shrinkage of tumour diameter on MRI. Lactate signals were present in high grade and unspecified astrocytomas and absent in most low grade gliomas. In 3 patients the lactate signal disappeared after radiotherapy. These observations indicate the feasibility of 1H-MRS in monitoring metabolic responses on radiotherapy of brain gliomas.  相似文献   
119.
Institute of Immunology, Ministry of Health of Russian. (Presented by Academician of the Russian Academy of Medical Sciences R. V. Petrov.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 506–508, November, 1992.  相似文献   
120.
Purpose: Our purpose was to examine implantation of singleton pregnancies achieved following various assisted reproductive technologies (ARTs) through the appearance and rising titers of serum human chorionic gonadotropin (hCG) levels. Methods: A total of 114 singleton pregnancies resulting from in vitro fertilization and intrauterine insemination was analyzed. Patients were divided into five groups according to the type of ovarian stimulation protocol [gonadotropin stimulation with/without the use of gonadotropin-releasing hormone agonist (GnRHa), long protocol, or flare-up technique] and to the day of embryo transfer (day 2 or day 3 after oocyte retrieval). Serial serum hCG levels were measured between 10 and 25 days after fertilization and log-transformed. Linear regression analyses were performed and extrapolated to hCG = 10 mIU/ml (hCG 10 ), which was used as an estimate of detectable implantation. The slopes of the regression lines were used to estimate the rising speed of hCG. Results: There were no significant differences in the days of hCG in maternal serum to reach 10 mIU/ml (implantation) or in the slopes of the regression lines for all five studied groups. Conclusions: The appearance of hCG in maternal serum was used to assess the time of clinically detectable implantation. Furthermore, because hCG production is a marker of trophoblastic activity, its serum doubling time was used as an indicator of embryo quality. Results showed that in various ART protocols with and without GnRHa, there were no significant differences in implantation time or embryo quality. Embryo development in early pregnancy follows a preprogrammed-timing schedule and depends mainly on the embryonic age of the health, successfully implanted conceptus.  相似文献   
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