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71.
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A morphological examination of 27 rats flown onboard the biosatellite and sacrificed on the 1st-2nd and 26-27th postflight days demonstrated no significant changes in the structural organization of the vital organs and systems of the animal body. It was, however, found that the space exposure induced morphologically detectable changes in the musculo-skeletal system, hemo- and lymphopoiesis, hypothalamic-pituitary-adrenal system and the juxtaglomerular apparatus of the kidneys. The changes were reversible and nonspecific, and could be seen in animals exposed to ground-based hypokinetic and other stress experiments. Postflight the animals developed some reactions that were similar to those in humans. This helps to identify the morphological substrate of certain changes in the human body and to investigate their pathogenesis.  相似文献   
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The literature on the stirred tank reactor with consecutive reactions is reviewed and a census of multiplicity diagrams, bifurcation diagrams and phase portraits is given. The location of the organizing centre, introduced by Balakotaiah and Luss, and some features of the butterfly singularity are discu particularly with reference to variations in the ratio of activation energies. The forms that the regions of attraction of the various steady states ma take in the three-dimensional state space are also discussed.  相似文献   
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We report a case of aortitis syndrome, in which carotid ultrasonography was a useful approach for the diagnosis. A 21-year-old woman was admitted to our hospital for persistent fever. No specific physical findings or laboratory abnormalities were observed except high fever and marked increase of erythrocyte sedimentation rate and c reactive protein. Since clinical trial of antibiotics and antituberculosis agents resulted in no effectiveness, prednisolone was started, but the effect was limited. After that, she complained of the neck pain, and vascular murmur became apparently audible at the pain site. Ultrasonography of the carotid artery revealed the smooth lumen and homogeneous, non-hyperechoic intimal thickening. Then aortography confirmed the diagnosis of aortitis syndrome. Cyclophosphamide combined with steroid therapy diminished the disease activity. In this case, carotid ultrasonography gave us the important information to enforce the aortography. If ultrasonography of the carotid artery has been popularized for aortitis syndrome, and its findings have been standardized, non-invasive diagnosis of this disease will be taken a step forward.  相似文献   
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A paired-comparison study of manual and automated (PAPNET) screenings of cervico-vaginal smears (Pap tests) was conducted to determine whether primary PAPNET screening was a reliable alternative to manual screening. A series of 5,037 consecutive Pap tests was first screened by the manual method. Next they were scanned by the PAPNET system, the DAT tapes were reviewed, and using a nonspecific triage protocol, abnormal tests were identified for limited, manual rescreening. False-negative rates (FNR) for each method were calculated and analyzed for due cause. By manual and PAPNET screening, respectively, there were 436 (8.6%) and 250 (4.9%) abnormal results. Manual screening missed 18 abnormals (5 SIL) and PAPNET 202 (7 SIL). The primary, manual screenings relating to the PAPNET false-negative tests were reviewed and revised to normal in 30. Based on the changes in the other 172 tests, cellular features ostensibly missed by the PAPNET system were listed to form part of a specific triage protocol, and were used to scrutinize the companion 172 DAT tapes: 150 tapes were abnormal. The manual FNR for an abnormal (SIL) result was 4% and (8.8%), respectively. Equivalent FNR pre- and postreviews for the PAPNET system were 44.6% (10.6%) and 5.2% (1.3%), respectively. This study discovered that the evaluation of some cell features in monitor-based, video images was the most important factor limiting the application of the PAPNET system as a primary screener. When governed by a specific triage protocol incorporating these features, primary PAPNET screening has the potential to equal the laboratory threshold of manual screening and be a better detector of SIL.  相似文献   
78.
Investigation of glycogen function in hepatocytes of different liver lobule zones is particularly important in understanding glycogen metabolism in humans and animals in norm and pathology. The present study was done to investigate glycogen contents in hepatocytes of different lobule zones of human liver in norm, and in patients with chronic hepatitis of viral or alcohol etiology. Quantitative analysis of glycogen content in hepatocytes of portal and central lobule zones was conducted on slices of human liver (the material of series live punctional biopsies) stained using a quantitative variant of PAS-reaction (Kudryavtseva et al., 1970, 1974). The measurements were done by image analyzer , which allows to make jointly cytophotometric analysis of substance in cells and definition of cell localization in tissue. The results showed clear differences of glycogen contents in different lobule zones in normal liver and in liver during chronic viral and alcohol hepatitis. Glycogen contents in hepatocytes of portal lobule zone were significantly higher than in the central lobule zone in patients with chronic viral hepatitis. Opposite data were obtained in patients with chronic alcohol hepatitis. Significantly higher glycogen contents were found in hepatocytes of the central liver lobule zone. Possible mechanisms of such a phenomenon are discussed . Thus, if glycogen contents in hepatocytes may be taken as an indicator of liver chronic damage degree (as has been shown elsewhere: Kudryavtseva, 1987; Kudryavtseva et al., 1988) the pattern of distribution of hepatocytes with different glycogen content in the liver lobule can be used as an indicator of etiology of chronic hepatitis. The obtained data seem to be important and actual, particularly for diagnostic of subclinical and symptomless forms of these diseases. Further investigation is required to find out reasons and mechanisms of this phenomenon.  相似文献   
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The development of a highly sensitive method for detection of telomerase activity, telomeric repeat amplification protocol (TRAP), has provided knowledge on telomerase activity in normal and cancer tissues. Subsequent several modifications have been achieved, including an introduction of the internal standard and hybridization protection technique that leads to simplicity and improvement of reproducibility and linearity of this method, and application of TRAP to in situ analysis to identify the cells responsible for telomerase activity. As for measurement of telomere length, fluorescence in situ hybridization technique appeared to give an information of telomere length on an individual chromosome in contrast to analysis of terminal restriction fragment, a conventional method which can express mean telomere length of all chromosomes. Further methodological improvement in this field is ongoing and showing a new sight on cell mortality and immortality.  相似文献   
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