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31.
Lufkin  RB; Hanafee  WN; Wortham  D; Hoover  L 《Radiology》1986,158(3):747-754
Forty patients with disorders of the larynx or hypopharynx were studied with magnetic resonance (MR) imaging. Axial, coronal, and sagittal sections, 4 mm thick, were obtained. Twenty-eight of the patients underwent computed tomography (CT) scanning; 17 underwent surgery, and specimens were obtained for organ sectioning. Correlation was made between these three studies as well as with clinical history, physical examination, and endoscopic photography. In 13 patients who underwent all three studies, the depiction of cartilage invasion, adenopathy, and intraorgan and extraorgan spread of disease was compared. MR consistently showed superior soft-tissue definition and extent of disease compared with CT. Neither CT nor MR was able to depict histologic detail or microscopic spread of disease. Both studies were also less effective in the postoperative or postirradiated neck. The use of direct coronal and sagittal imaging planes on MR allowed the visualization of intrinsic laryngeal musculature, which was important in the recognition of subtle tumor extension. For these reasons, surface coil MR imaging is currently the imaging study of choice at our institution for disorders of the larynx and hypopharynx.  相似文献   
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Granulocytic sarcoma (chloroma): CT manifestations   总被引:2,自引:0,他引:2  
Nests of granulocytic tumor cells in patients who have myelogenous leukemia are termed chloromas. Eight cases of chloroma seen on CT were reviewed. Lymph nodes, subcutaneous tissues, peritoneum, pleural space, pelvis, and portal hepatis were involved. Two patients exhibited chloroma as the sole manifestation of their disease during bone marrow remission. The extracranial appearance of chloroma on CT is that of small, nonenhancing, nodular densities that resemble lymphoma. Cranial involvement is characteristically in the orbit. The central nervous system appearance is variable, however, and high attenuation masses may occur that mimic lymphoma, hematoma, and metastatic neuroblastoma. The recognition of these lesions is important, since radiation, not chemotherapy, is often the preferred treatment for localized chloroma.  相似文献   
34.
Thermotolerance involves more than life or death. Investigating the complexity of this trait will aid identification of its genetic contributors. We examined variation in thermally stressed walking behavior and performance in natural Drosophila melanogaster strains and strains mutant for the heat shock protein Hsp70, to determine which aspects of locomotion are affected by heat shock and genotype. We developed software for the large-scale capture, analysis, and visualization of locomotion, and determined: (1) Heat shock and thermal pretreatment significantly and differentially impact fly locomotor behavior and performance. (2) Stressed locomotion traits vary extensively among natural strains. (3) Interactions among treatments, strains, and traits are substantial and often counterintuitive. (4) Hsp70 overexpressing flies are faster and more basally thermoprotected in performance than Hsp70 null flies, but null flies are more unidirectional. (5) Natural variation in most stressed locomotion traits exceeds that caused by Hsp70 mutation, reveals uncoupling between thermoprotection of behavior and performance, and suggests significant genetic variation for trait-specific modifiers of thermotolerance. Edited by Yong-Kyu Kim.  相似文献   
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Sequences related to the mouse mammary tumor virus (MMTV) genome have been detected in fragments of restricted human cellular DNA. These results were obtained by using recombinant DNA containing the MMTV proviral genome and lowering the stringency of blot-hybridization conditions. The MMTV genome also reacts with unique families of fragments in restricted cellular DNA from other mammalian species but not with salmon sperm DNA. A clone that reacted with labeled MMTV proviral DNA was selected from a human DNA library in Charon 4A. Under stringent conditions, a 3.7-kilobase MMTV-related EcoRI fragment of this clone hybridized with many of the same EcoRI restriction fragments of human cellular DNA detectable with MMTV proviral DNA under low-stringency conditions. Specific fragments of the human clone were shown to contain sequences related to the molecularly cloned gag, pol, and env regions of the MMTV genome.  相似文献   
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38.
报道了39个新的1-{2-[(取代苯基)甲氧基]-2-(取代苯基)乙基}-1H-三唑和苯并三唑类化合物的合成与体外抑菌试验,结果表明,化合物6,13的抗真菌活性为益康唑的4~10倍,化合物10,12,14,15,20,22,23,28.30和31等对大部分真菌活性也优于或相当于益康唑及克霉唑,化合物23和31抗裴氏着色菌活性为益康唑、克霉唑的30倍以上,化合物22抗白念珠菌活性为益康唑的8倍,克霉唑的4倍。  相似文献   
39.
The purpose of this article is to encourage primary care pediatric nurses to begin behavioral-based obesity treatment efforts as early as the preschool years. By examining the critical periods for obesity development and how the formation of food and activity behaviors interacts with those critical periods during the preschool years, the value of initiating early obesity treatment will be highlighted. Furthermore, the theory of behavior modification is presented and core principles are applied to early childhood weight management efforts.  相似文献   
40.
OBJECTIVES: To examine the safety and pharmacokinetics of multiple intratracheal (IT) doses of recombinant human CuZn superoxide dismutase (rhSOD) in premature infants with respiratory distress syndrome who are at risk for developing bronchopulmonary dysplasia (BPD). Methods. Thirty-three infants (700 to 1300 g) were randomized and blindly received saline, 2.5 mg/kg or 5 mg/kg rhSOD IT within 2 hours of surfactant administration. Infants were treated every 48 hours (as long as endotracheal intubation was required) up to 7 doses. Serial blood and urine studies, chest radiographs, neurosonograms, SOD concentration and activity measurements, and tracheal aspirate (TA) inflammatory markers were assessed throughout the 28-day study. RESULTS: SOD concentrations in serum (0.1 [0.05/0.15] microg/mL-geometric mean with lower/upper confidence intervals), tracheal aspirates (TA) (0.2 [0.1/0.3] microg/mL) and urine (0.3 [0.2/0.4] microg/mL) were similar at baseline in all 3 groups and did not change significantly in the placebo group. In the rhSOD treatment groups, SOD concentrations were increased on day 3 and did not change significantly thereafter over the 14-day dosing period (also measured on days 5, 7, and 13). SOD concentrations averaged 0.4 [0.3/0.5] microg/mL in serum, 0.8 [0.6/1.2] microg/mL in TA and 1.1 [1.0/1.3] microg/mL in urine for the low-dose group and 0.6 [0.5/0.7] microg/mL in serum, 1.1 [0.9/1.5] microg/mL in TA, and 2.2 [1.6/2.9] microg/mL in urine for the high-dose group over the 14-day dosing period. Enzyme activity directly correlated with SOD concentration and rhSOD was active even when excreted in urine. TA markers of acute lung injury (neutrophil chemotactic activity, albumin concentration) were lower in the rhSOD agroups compared with placebo. No significant differences in any clinical outcome variable were noted between groups. CONCLUSIONS: These data indicate that multiple IT doses of rhSOD increase the concentration and activity of the enzyme in serum, TA and urine, reduce TA lung injury markers and are well-tolerated. Further clinical trials examining the efficacy of rhSOD in the prevention of BPD are warranted.  相似文献   
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