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991.
992.
The emergence of a near-haploid clone of cells in blast phase chronic myelogenous leukemia is an unusual event. We report such a case and review eight other cases described in the English literature. The significance of the substantial loss of genetic material is discussed as is the phenotypic and genotypic heterogeneity observed in this group of patients.  相似文献   
993.
The findings of a study of the frequency and type of psychotropic drugs that nonpsychiatric residents prescribed for nonpsychiatric patients in a teaching hospital in 1982 were compared with the findings of a similar study in the same hospital nine years earlier. The overall percentage of patients receiving psychotropic drugs remained almost the same, at less than 10 percent. However, in 1982 residents prescribed antidepressants almost four times as often as in 1973, and the use of antianxiety agents decreased. Deficiencies in chart documentation of psychotropic prescribing and the tendency to use conservative dosages remained unchanged from the earlier study.  相似文献   
994.
995.
We evaluated the isoform composition of heavy and light chains of myosin in single muscle fibers from patients with Duchenne dystrophy, myotonic dystrophy, or polymyositis. In all myopathic muscles, there was an increase in the proportion of intermediate fibers which, by analysis of myosin isoforms, fell into two subpopulations, one that contained both fast and slow myosin and another that contained myosin molecular hybrids. The increased proportion of intermediate (or transitional) fibers suggests changes in the equilibrium between fast and slow motor units. These changes could result from regeneration and subsequent maturation of fibers or from direct transformation of mature fibers of one type into the opposite.  相似文献   
996.
997.
Carcinoma of the gallbladder   总被引:1,自引:0,他引:1  
Gallbladder carcinoma is the fourth commonest gastrointestinal malignancy. Its growth is insidious and the majority of cases are advanced at the time of diagnosis. The recognized radiological features occur only in those with advanced disease. Cholecystectomy may be curative when carcinoma is confined to the gallbladder but the place of extensive surgery, chemotherapy or radiotherapy is unproven.  相似文献   
998.
Information is an important and even essential step in the prevention process. An exhibition, which traditionally favours a visual approach, is a way of providing information for the public at large. The exhibition, the first to be produced under the auspices of the Claude Verdan foundation, tackles the issue in a general way. The aim is to: make people aware and encourage prevention in the work environment; situate the hand in a preventive context; show the importance of the hand as a work-tool; present the quantitative and qualitative extent of diseases and accidents of the hand; make the interest and difficulties in collecting information known (especially about professional diseases and workers not affiliated to the CNA); stimulate continuing search of information about prevention in the work environment. The exhibition presents certain aspects of the history of prevention in the working world, Swiss institutions involved, notions of epidemiology of professional diseases and accidents of the hand (obtained from the CNA files), as well as different types of available prevention. The material used is light (posters, slides, video) and thus transportable, and so can be widely used for the people concerned at their place of work....  相似文献   
999.
1000.
Compared with results obtained in locally anesthetized, paralyzed rats, the dissociative anesthetic ketamine did not alter either the number of spontaneously active striatal neurons or the basal firing rate of striatal neurons; 90% of these cells exhibited the type I striatal neuron waveform. Chloral hydrate anesthesia suppressed both the occurrence and the firing rate of spontaneously active type I cells, but did not alter the activity of type II striatal neurons. Cortical stimulation preferentially activated type II cells in paralyzed rats and in chloral hydrate-anesthetized rats. Thus, under dissociative anesthesia it is possible to study spontaneously active type I striatal neurons. However, a method of activation such as cortical stimulation is necessary to study type II striatal neurons.  相似文献   
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