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121.
Actinic cheilitis. A prospective study comparing four treatment methods   总被引:1,自引:0,他引:1  
Forty patients with actinic cheilitis were treated with one of four modalities: topical fluorouracil, chemical peel with trichloroacetic acid, lip shave, or carbon dioxide laser ablation of the vermilion. Patients treated with lip shave or carbon dioxide laser ablation had no recurrence of the problem during a 4-year period. While the lip shave procedure offers the advantage of histologic examination of the specimen, the patients treated with the laser ablation had fewer postoperative complications.  相似文献   
122.
Thirteen patients with sickle cell disease (SCD) undergoing transfusion therapy and 8 control patients were examined by magnetic resonance imaging to discriminate bone marrow change due to iron deposition from hematologic marrow hyperplasia. Using T1-weighted spin echo images, only two subjects showed extremely low signal intensity marrow compatible with iron deposition. However, using T2-weighted fast spin echo images with fat suppression, cranial bone marrow in SCD patients with transfusion therapy showed considerably lower signal than that of controls. The main cause of marrow signal decrease in SCD patients with transfusion therapy was considered to be iron deposition due to repeated transfusion therapy rather than red marrow hyperplasia.  相似文献   
123.
Ingested matter can have a significant effect on whole body metal concentration measurements in Mytilus edulis. Depuration of mussels in clean seawater for 36 h prior to dissection eliminates most of these contaminating gut contents. Depuration followed by metal analyses is the most direct method of determining mussel tissue metal bioburdens. After being transplanted into a plume of primary treated sewage effluent in Salem Harbor, Massachusetts for 32 days, Al, Cr, and Fe concentrations in depurated mussels were significantly lower than those determined for either non-depurated mussels or for depurated mussels to which fecal concentrations of Al, Cr, and Fe were added back in. Although mathematical methods developed by both Ouellette (1978) and Boehm et al. (1988) could be applied to non-depurated mussels in order to correct for errors associated with gut metal contamination, these indirect methods were not as reliable as depuration prior to analysis.  相似文献   
124.
The suprachiasmatic nucleus (SCN) of rat and hamster have been studied extensively and shown to play critical roles in circadian rhythmicity. [125I]Vasoactive intestinal peptide (VIP) binding levels are high in the rat SCN, suggesting that VIP receptors may be an important component of SCN function. In contrast to previously demonstrated diurnal variations in VIP immunoreactivity and VIP mRNA, the present study found [125I]VIP binding to be stable across the light-dark cycle in both rat and hamster SCN. High [125I]VIP labeling appeared to be coextensive with the rat SCN but extended somewhat beyond the cytoarchitectonic boundaries of the hamster SCN. Binding density in hamster SCN was slightly higher than in rat. In the developing rat SCN, [125I]VIP binding levels distinguished the SCN on embryonic day 18, and appeared to increase to postnatal day 10 before declining to adult levels. The early presence of [125I]VIP binding suggests possible involvement of VIP receptors in fetal entrainment of circadian rhythms.  相似文献   
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126.
Federal and state codes exist regarding administering and dispensing medications and there is variation between the two. Recognition of the differences is imperative for the athletic trainer, who has traditionally dispensed these agents in compliance with established legal and professional guidelines. Statutes that apply to classifying, documenting, prescribing, dispensing, labeling, and housing medications by athletic trainers are presented as a baseline for this article. State and local regulations should be consulted to clarify differences existing at various governmental levels. These guidelines are provided to assist athletic trainers in properly dispensing medications.  相似文献   
127.
Adult workers in honeybee (Apis mellifera) colonies exhibit plasticity in hormonally regulated, age-based division of labor by altering their pattern of behavioral development in response to changes in colony conditions. One form of this plasticity is precocious development: levels of juvenile hormone increase prematurely and bees begin foraging as much as 2 weeks earlier than average. We used two experimental paradigms inspired by developmental biology to study how bees obtain information on changing colony needs that results in precocious foraging. An analog of "cell culture," with bees reared outside of colonies in different sized groups, revealed that worker-worker interactions exert quantitative effects on endocrine and behavioral development. "Transplants" of older bees to colonies otherwise lacking foragers demonstrated that worker-worker interactions also affect behavioral development in whole colonies. These results provide insights to a long-standing problem in the biology of social insects and further highlight similarities in the integration of activity that exist between individuals in insect colonies and cells in metazoans.  相似文献   
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129.
An absolute lymphocyte count is included in the routine results provided by most automated blood cell counters, providing a prompt indication of peripheral blood lymphocytosis. Transient lymphocytosis is seen in many acutely ill patients, including those with multiple injuries. We have observed a significantly higher death rate among trauma patients with lymphocytosis at presentation; patients with lymphocytosis, on subsequent assessment of injury, proved to have higher Injury Severity Scores than those without lymphocytosis. Investigation of lymphocyte subsets in nine patients with lymphocytosis showed an increase in T cells, reversal of the CD4:CD8 ratio, and, in seven patients, an increase in "natural killer" cells. The presence of lymphocytosis and its early detection as part of a routine blood count may supply a readily available means of identifying a high-risk trauma patient.  相似文献   
130.
A set of 1638 informative SNP markers easily assayed by the Amplifluor genotyping system were tested in 102 mouse strains, including the majority of the common and wild-derived inbred strains available from The Jackson Laboratory. Selected from publicly available databases, the markers are on average ~1.5 Mb apart and, whenever possible, represent the rare allele in at least two strains. Amplifluor assays were developed for each marker and performed on two independent DNA samples from each strain. The mean number of polymorphisms between strains was 608±136 SD. Several tests indicate that the markers provide an effective system for performing genome scans and quantitative trait loci analyses in all but the most closely related strains. Additionally, the markers revealed several subtle differences between closely related mouse strains, including the groups of several 129, BALB, C3H, C57, and DBA strains, and a group of wild-derived inbred strains representing several Mus musculus subspecies. Applying a neighbor-joining method to the data, we constructed a mouse strain family tree, which in most cases confirmed existing genealogies.  相似文献   
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