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Ritschl  P.  Karnel  F.  Hajek  P. 《Skeletal radiology》1988,17(1):8-15
The radiomorphological appearance of fibrous metaphyseal defects (FMDs) is demonstrated by long-term follow-up studies. A characteristic radiomorphological course rather than a typical single appearance can be established. These findings correlate well with the duration of these tumor-like lesions; therefore, the radiological findings allow conclusions to be made about the age of a fibrous metaphyseal defect. In addition, the characteristic locations of FMDs will be explained in respect of their origins at insertions of tendons and ligaments.  相似文献   
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The relationship between the use of cigarettes and other tobacco products and the risk of multiple myeloma was examined in a cohort of nearly 250,000 American veterans followed prospectively for 26 years. Compared with men who had never used tobacco, the risk of death from myeloma was not increased among current (relative risk [RR]=0.9, 95 percent confidence interval [CI]=0.8–1.2) or former (RR=1.0, CI=0.8–1.3) cigarette smokers, nor among users of chewing tobacco or snuff (RR=1.0, CI=0.4–2.3). Risk was only slightly and nonsignificantly increased among pipe or cigar smokers (RR=1.2, CI=0.9–1.5). There was no indication of increasing risk with amount of tobacco used or earlier age at first use. With over 90 percent power to detect a 30 percent increased risk of this tumor occuring among current cigarette smokers, this study provides the strongest evidence to date against an association of cigarette smoking with multiple myeloma.Epidemiology and Biometry Program, Division of Cancer Etiology, National Cancer Institute. Westat, Inc. Rockville, MD. National Cancer Institute, 6130 Executive Blvd, Room 418, Rockville, MD 20892, USA.  相似文献   
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A double-blind, placebo controlled trial was undertaken to examine the effect of the 5-HT3 antagonist, ondansetron .25 mg bd on cigarette withdrawal symptoms and on proportion of individuals maintaining continuous abstinence for 4 weeks in a smoking treatment programme. A total of 111 smokers were allocated to active or placebo conditions and began taking their study medication 2 weeks before the quit date. They attended the smokers clinic for weekly group treatment sessions. The results showed no evidence for less severe withdrawal symptoms or improved abstinence rates in the active medication group. They suggest that inhibiting 5-HT3 activity is not an effective method of controlling nicotine withdrawal or helping smokers to stop.  相似文献   
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In a radiologic search for embolized leaflets of Edwards-Duromedics bileaflet valves in 2 patients, the embolized fragments were localized in the iliac vessels using computed tomography. Sonography was successful in one case and standard X-ray films of the abdomen were negative in both cases.In vitro investigations with Björk-Shiley and Edwards-Duromedics leaflets suggested that standard X-ray films of the abdomen and pelvis should be considered as the first investigational technique. If negative, computed tomography of the lower abdomen should be done.  相似文献   
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A single-purpose analogue-computing device is described for the online assessment of the contractile state of the human myocardium from the left ventricular pressure (Plv) data available during routine cardiac catheterisation. Due attention has been paid to the design of the computer circuits so that they will not process pressure phenomena outside the isovolumic contractile period. Either a \(\left( {\frac{1}{{P_{lv} }}\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) or a plain \(\left( {\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) index is presented on a digitalvoltmeter display, thus obviating the need for any graphical extrapolation or additional computation.  相似文献   
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Postnatal mice lacking neurotrophin-3 (NT3) are deficient in Merkel cells of touch domes and whisker follicles. We examined the mechanism of Merkel cell loss by immunocytochemistry and electron microscopy. Merkel cell of whisker follicles of NT3 null newborns exhibited decreased immunoreactivity for cytokeratin 8 and contained apoptotic bodies that were positive for cleaved caspase-3, a marker of active apoptosis. By electron microscopy, the Merkel cells displayed aggregation of chromatin along the nuclear membrane, with the marginated chromatin forming caps at the periphery of the nucleus. Ribosomes aggregated in the cytoplasm, while dense core granules characteristic of Merkel cells were still discernible. Finally, the Merkel cells and their nuclei fragmented into apoptotic bodies. None of the apoptotic Merkel cells were contacted by nerve fibers, and their desmosomal contacts with surrounding keratinocytes disappeared. After postnatal day 6 apoptotic Merkel cells were no longer observed, and the number of surviving Merkel cells was severely reduced. They were flat and contained few osmiophilic granules. We conclude that perinatal apoptosis is responsible for the loss of Merkel cells lacking innervation in NT3 null mice.  相似文献   
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Seventy-seven smoker clinic clients who managed at least 2 weeks of smoking abstinence while chewing 2 mg nicotine gum reported the degree to which the gum reduced their craving for cigarettes, their daily gum consumption and the extent of urges to smoke despite the gum. Greatest relief from craving by the gum was reported by smokers with higher pre-abstinence expired-air carbon monoxide (CO) concentrations and higher stimulant and dependent scores on a smoking motivation questionaire but not greater usual daily cigarette consumption. Gum consumption correlated positively with expired-air CO, usual daily cigarette consumption, and stimulant and dependent smoking scores. Despite the gum, urges to smoke and difficulty not smoking were reported and the severity of these was associated with indulgent, stimulant and dependent smoking scores but not CO or usual daily cigarette consumption. The results are discussed in terms of the possible role of pharmacological and non-pharmacological factors in craving.  相似文献   
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