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1.
Fine-needle aspirates (FNAs) of 84 primary breast carcinomas were analyzed immunocytochemically for estrogen receptor (ER) using (ER-ICA) monoclonal antireceptor antibodies. ER-ICA in FNAs was concordant to ER-ICA in histologic biopsies in 87% (P less than 0.0001). In most of the carcinomas, biochemically determined ER status also correlated to ER-ICA. There was no false positive ER-ICA in FNAs compared with ER-ICA in histologic biopsies. In 11 FNAs, ER-ICA was negative, whereas it showed positivity in histologic specimens. The most frequent contributing factors to false negative ER-ICAs of FNAs were ER-ICA-low results in histologic biopsies, a prominent stroma component in these tumors, and low cellularity of FNAs. The biochemical ER values in these cases never exceeded 90 fmol/mg protein. In a minority of cases, false negative results were inexplicable.  相似文献   
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X-ray fluorescence tomography promises to map elemental distributions in unstained and unfixed biological specimens in three dimensions at high resolution and sensitivity, offering unparalleled insight in medical, biological, and environmental sciences. X-ray fluorescence tomography of biological specimens has been viewed as impractical—and perhaps even impossible for routine application—due to the large time required for scanning tomography and significant radiation dose delivered to the specimen during the imaging process. Here, we demonstrate submicron resolution X-ray fluorescence tomography of a whole unstained biological specimen, quantifying three-dimensional distributions of the elements Si, P, S, Cl, K, Ca, Mn, Fe, Cu, and Zn in the freshwater diatom Cyclotella meneghiniana with 400-nm resolution, improving the spatial resolution by over an order of magnitude. The resulting maps faithfully reproduce cellular structure revealing unexpected patterns that may elucidate the role of metals in diatom biology and of diatoms in global element cycles. With anticipated improvements in data acquisition and detector sensitivity, such measurements could become routine in the near future.  相似文献   
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OBJECTIVE: The objectives of this study were to investigate the influence of psychological factors on the recovery of surgical patients and to explore whether there are any psychological variables other than anxiety that have a significant influence on recovery from surgery. METHODS: The participants were 112 adult patients undergoing a variety of surgical procedures. On the day prior to surgery, the Freiburg Personality Questionnaire, the State-Trait Anxiety Inventory, a coping schedule and the Questionnaire of Social Support were used to measure psychological parameters including personality, anxiety, coping and social support. The quality of the surgical outcome was rated by two independent and blinded surgeons by the length of hospital stay and analgesia and sedation requirements. The ratings controlled for the diagnosis, type of operation, intraoperative complications, postoperative medical problems and health limitations independent of the surgical procedure. RESULTS: Patients who had a complicated recovery were found to have reduced life satisfaction and lower situation-specific self-control expectations. Structural equation modeling revealed direct relationships between recovery from surgery and personality dimensions with the strongest correlations to life satisfaction, extraversion and attainment orientation. CONCLUSION: The data from this study suggests that valid predictions of the course of postoperative recovery need to take into account personality and coping behaviour orientated data as well as clinical variables. No direct influence on recovery could be predicted from preoperative state anxiety, but it seems likely that state anxiety may influence coping behaviour and that it is this that appears to have a significant impact to surgical recovery.  相似文献   
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Arterial hypertension is the most important risk factor in all types of stroke. The significance of alcohol in the pathogenesis of stroke is less well defined. Chronic alcoholism leads to an elevation of blood pressure. Thus, the association between alcohol and stroke might be the blood pressure effect of alcohol. However, some studies have shown a significant influence of alcohol on the incidence of stroke--especially of intracerebral haemorrhage and subarachnoid haemorrhage--even after adjustment for blood pressure. Many possible pathomechanisms are discussed. Alcohol inhibits aggregation of thrombocytes, and chronic alcohol abuse may induce thrombocytopenia, which could lead to a haemorrhagic stroke. Alcohol withdrawal leads to rebound thrombocytosis. Acute alcohol ingestion induces a decrease in fibrinolytic activity and an increase in factor VIII activity, which enhances the thrombotic potential. Additionally, alcohol increases plasma osmolarity, erythrocyte aggregability, haematocrit and blood viscosity, and decreases deformability of erythrocytes. The effects of alcohol on cerebral blood flow are still under debate; there is a deterioration in autoregulation of cerebral blood flow anyway. In animal studies alcohol induced dose-dependent vasospasm of the cerebral blood vessels, which could be a possible pathomechanism in ischaemic, as well as in haemorrhagic stroke. Chronic alcoholism is the most common cause of secondary non-ischaemic cardiomyopathy, which can lead to cerebral embolism via rhythm disorders or intracardiac thrombus formation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Stimulation response of the pituitary to LHRH and testicular biopsy were investigated in 17 infertile men in comparison to 10 healthy controls. A significant elevation of basal FSH and LHRH-stimulated FSH serum levels was observed in Sertoli cell only syndrome and spermatogenetic arrest, while LH and testosterone remained normal. The LHRH test seems to be of value for differentiation of pretesticular, testicular and posttesticular infertility.  相似文献   
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Polypoid lesions of the colon are commonly accepted risk factors for the development of carcinomas of the colon. Fifty-two of 266 patients with one or more polypoid lesions of the colon showed a carcinoma in one of the polyps, 6 patients had a second carcinoma. Our study demonstrates the importance of preoperative investigation of the total colon in patients with carcinoma of the colon. Furthermore, the necessity of total exstirpation of each polypoid lesion is discussed.  相似文献   
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Introduction  

Patients suffering from brain tumours often experience a wide range of cognitive impairments that impair their ability to report on their quality of life and symptom burden. The use of proxy ratings by significant others may be a promising alternative to gain information for medical decision making or research purposes, if self-ratings are not obtainable. Our study investigated the agreement of quality of life and symptom ratings by the patient him/herself or by a significant other.  相似文献   
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