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31.
Gestational trophoblastic diseases (GTD) is an abnormal condition of the placenta, the incidence of which is very high in the State of Kerala, India. Placentae of normal (50) and molar pregnancy (122) including 52 showing persistent disease were used for the study. EGFR and EGF expression was analyzed by immunohistochemistry using monoclonal antibodies. EGF receptors were quantitated using the I-125 EGF-binding assay and that of EGF was quantitated using isotope labelled antibody to EGF. Tumours with histological diagnosis of invasive moles and choriocarcinoma showed very strong binding of both EGF and EGFR. The present observations also suggest the possibility of presence of mutated EGF receptors in persistent trophoblastic disease.  相似文献   
32.
The aim of this study was to determine the number and size of apical non-myelinated (C) axons of healthy human premolars. The material was derived from a large collection of specimens prepared for a previous quantitative investigation on the myelinated (A) axons of human premolars. A total of 16 teeth (six maxillary first and five each of mandibular first and second premolars), removed from adolescents for orthodontic reasons, were used. Root discs of about 0.6 mm thickness were prepared at about 2 mm cervical to the root apex and processed for light and electron microscopy. The number of non-myelinated axons was determined by taking a total census of such fibres that could be identified and reconstructed by standardized composite electron micrographs from each root disc. The measurement of axons was done on a statistically representative sample of axons (n=1810) using an electronic image processing unit. The 16 teeth had an average of 2000 ± 1023 non-myelinated axons at the juxta-apical level (range 534–3912). The average diameter of the non-myelinated axons was found to be 0.5 ± 0.4 m (range 0.05–2.4 m).  相似文献   
33.
Involvement of the central nervous system in epithelial ovarian carcinoma is rare. A 46-year-old woman with ovarian carcinoma relapsing with brain metastasis is described. She received radiotherapy for the metastasis and survived for 18 months.  相似文献   
34.
The purpose of this study is to determine the individual contribution, or importance number, of the symptoms to an analysis of depression, utilizing a neural network model. In addition, the presence of hopelessness and somatic complaints was examined, to determine their relevance to depression. Using Wave 1 data from Duke University's contribution in the Epidemiological Catchment Area (ECA) study, we created a mathematical model, a neural network, to map the relationship of nine symptoms of major depression, hopelessness and somatic complaints to the presence or absence of the formal diagnosis of depression, and performed a contribution analysis. The contribution analysis using the neural network revealed that the symptoms with the greatest impact on the occurrence of depression, or with the largest importance number for depression, were sadness, loss of interest, tiredness and sleeping trouble, in that order. The most frequently reported symptoms, though, were sadness, sleeping trouble, suicidal ideation, tiredness and poor concentration, in that order. Hopelessness and somatic symptoms were the lowest in their contribution to the diagnosis of depression. The study thus provides the hierarchy of the symptoms of depression and supports the DSM classification of major depression.  相似文献   
35.
The present study elucidates the effect of undernutrition on pulmonary functions in children. The study was carried out in healthy normals, wasted, wasted and stunted children. Spirometry was performed with Vitalograph Compact-II spirometer. Wasted, wasted and stunted children showed lower lung volumes, forced mid expiratory flow time and inspiratory flow rates than healthy normals. Wasted and stunted children had lower VC, FVC and FIF50% than wasted children. The reduction in lung volumes and flow rates in wasted children may be due to ventilatory muscle wasting. But in wasted and stunted children along with muscular wasting diminished skeletal growth is also a reason for lower lung functions. No airflow limitation was observed in undernourished children.  相似文献   
36.
Cell proliferation is an important biological aspect of a tumor cell population which can affect clinical outcome. In addition to other well established clinical and histopathological prognostic criteria? cell kinetic data have significant predictive value. This study evaluates the proliferative activity of benign, premalignant and malignant cervical tissue by analyzing the expression of the proliferating cell nuclear antigen (PCNA). PCNA is a 36 kD nuclear protein associated with the cell cycle and is directly involved in DNA synthesis during cell proliferation. A total of 122 subjects were included in the study. This included 30 benign tissue samples, 30 low grade lesions (CIN 1), 30 high grade lesions (CIN 2/3) and 32 invasive squamous carcinomas. There was significant difference in PCNA index between benign and high grade lesions as well as benign and invasive cancer. The percentage of PCNA positive cells were significantly higher in invasive carcinoma when compared with non malignant lesions. Moreover, there was also good correlation between increasing histological abnormality and PCNA expression. These results suggest that cell proliferation index as detected by PCNA expression may be useful in the evaluation of alterations in cell kinetics of various grades of cervical lesions. Such data could also possibly help explain the biological behaviour of these lesions and be useful in planning of radiotherapy for invasive cervical cancer.  相似文献   
37.
Dose distribution patterns of 4 MV x-rays from a Varian Clinac 4 linear accelerator are compared with those from a 60Co teletherapy machine. Field flatteners of lead and depleted uranium were used. Dose distribution maps display the off-axis high dose or "horns" with lead filters and circular dose distribution patterns. The uranium field flattener clearly "clipped the horns" and eliminated circular dose distribution patterns with larger fields.  相似文献   
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