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31.
The asymptomatic patient with suspected myocardial contusion 总被引:4,自引:0,他引:4
M B Foil R C Mackersie S R Furst J W Davis M S Swanson D B Hoyt S R Shackford 《American journal of surgery》1990,160(6):638-42; discussion 642-3
Diagnostic criteria and guidelines for hospital admission for suspected myocardial contusion (MCC) remain unclear. This study defines and examines the clinical sequelae of patients admitted with a suspicion of MCC. Criteria for observation following isolated, minor blunt chest trauma are suggested. Hospital and trauma registry records of patients admitted over a 33-month period with suspected MCC were reviewed. Conventional evaluation criteria, cardiac-related complications, and associated injuries were analyzed for 524 patients. Twenty-eight cardiac-related complications occurred in 27 of 524 patients (5%). These complications included 23 dysrhythmias, 3 infarctions, and 2 pericardial effusions. There were 23 patients with abnormal admission electrocardiograms and 4 with normal ones. Of the latter, one patient developed dysrhythmia 4 hours after admission, and three had other major multi-system injuries requiring admission to the intensive care unit. The overall incidence of cardiac-related complications in minimally injured patients was 0.1%. There were no complications in patients with isolated chest wall contusions, a normal admission electrocardiogram, and a normal rhythm at 4 hours. There was no significant association between creatine phosphokinase isoenzymes or echocardiogram and cardiac-related complications. The complete absence of significant cardiac sequelae in patients with isolated chest wall contusion, normal admission and 4-hour electrocardiograms, and no other associated major injuries suggests that these patients need not be admitted. 相似文献
32.
A 60-year-old man with a history of diabetes insipidus presented with a left groin mass, leg edema, and retroperitoneal adenopathy. Biopsy results of the involved lymph nodes were typical of eosinophilic granuloma. The patient was treated with etoposide and prednisone and had a complete regression of his lymphadenopathy and edema. This response suggests that etoposide may be a useful agent in the management of histiocytosis X. 相似文献
33.
Paul A. Demers Thomas L. Vaughan Thomas D. Koepsell Joseph L. Lyon G. Marie Swanson Raymond S. Greenberg Noel S. Weiss 《American journal of industrial medicine》1993,23(4):629-639
Lifetime job histories from a population-based, case-control study were analyzed to investigate the relationship between multiple myeloma and employment in various occupations and industries. Interviews were obtained from 89% (692) of eligible incident cases and 83% (1683) of eligible controls. An elevated risk was observed among persons ever employed as painters [odds ratio (OR) + 2.1, 95% confidence interval (CI) + 1.2–3.6], particularly for those employed for 10 or more years (OR + 4.1, 95% CI + 1.8–10.4). A small excess risk was observed among agricultural workers employed for 10 or more years (OR + 1.3, 95% CI + 1.0–2.2), with a higher relative risk observed among farm laborers (OR + 1.8, 95% CI + 1.0–4.0). Among agricultural workers who reported having been highly exposed to pesticides, the OR was 5.2 (95% CI + 1.6–21.1). Some evidence, based on smaller numbers, was also found to support an association with firefighting and employment in the petroleum- and coal-products manufacturing industries. Little evidence was found to support the previously noted association with wood exposure, and no evidence for an association with employment in the rubber or petroleum refining industries was found. This study lends further support to previously reported associations between multiple myeloma and employment among painters and agricultural workers. © 1993 Wiley-Liss, Inc. 相似文献
34.
Tyrosine hydroxylase and serotonin containing cells in embryonic rat rhombencephalon: a whole-mount immunocytochemical study 总被引:5,自引:0,他引:5
Rhombencephala from rat embryos were processed as whole-mounts for immunocytochemical detection of monoaminergic cell populations, using antibodies to tyrosine hydroxylase (TH) and serotonin (5-HT). Specific advantages of the whole-mount technique over the classical serial-section method were that even isolated immunoreactive (IR) cells could be detected easily, and three-dimensional relationships could be ascertained without the need for serial reconstruction. Embryos between embryonic days (E) 12 and 16 (the day following nocturnal mating being considered as E1) were used in this study. Both TH and 5-HT immunoreactivities were already detectable at E12, even in the smallest embryos (crown-rump length: 6 mm), but there was a striking difference in the number and regional distribution of these two types of IR cells. TH was expressed in several cell groups located in the rostral rhombencephalon (the presumed anlage of the A4-7 complex) as well as in the caudal rhombencephalon (the presumed anlagen of groups A1-2 and C1-3), whereas 5-HT was expressed in very few cells located near the rostral border of the rhombencephalon (presumed anlage of the B4-9 complex). Although the three-dimensional distribution of the TH-IR cell groups underwent some modifications during the period studied, its general pattern remained relatively stable after E12. This contrasted with the sequential appearance of the 5-HT-IR cell groups and their spatial transformations during this period. Using the rhombencephalic isthmus as a landmark, we found that conspicuous 5-HT-IR fibre bundles penetrated into the mesencephalon from E13 onwards, but that the 5-HT IR cell bodies were exclusively located caudal to the borderline between the mesencephalon and the rhombencephalon (the rhombencephalic isthmus). We therefore suggest the term "rostral rhombencephalic raphe nuclei" for the rostral 5-HT cell groups instead of "mesencephalic raphe nuclei," which is a misnomer. Close spatial association between TH and 5-HT-IR elements was observed mainly in the caudal rhombencephalon, where 5-HT-IR fibres coursed through an area containing numerous TH-IR cell bodies (the presumed anlagen of groups A1-2 and C1-3). 相似文献
35.
Chronic lymphocytic leukemia in relation to chemical exposures 总被引:8,自引:0,他引:8
K E Malone T D Koepsell J R Daling N S Weiss P D Morris J W Taylor G M Swanson J L Lyon 《American journal of epidemiology》1989,130(6):1152-1158
As part of a population-based case-control study carried out in four areas of the United States, 427 cases of chronic lymphocytic leukemia diagnosed between July 1, 1977, and December 31, 1981, and 1,683 controls were interviewed regarding their history of chemical exposure. Respondents were asked if they had ever been "highly exposed" at home, at work, or elsewhere to one or more of a list of chemicals or to any other such substances not on the list. These chemicals were categorized into 20 exposure groups based on chemical composition. Odds ratios were calculated adjusting for age, sex, race, education level, and geographic location by means of unconditional logistic regression. Increased risks were associated with reported past exposure to acid-containing chemicals, "other caustic substances," aliphatic hydrocarbons, and chlorinated hydrocarbons. Because of the large number of exposures investigated in this study, and because of the relatively imprecise means the authors had to assess exposure, further research is needed to verify these findings. 相似文献
36.
Owens EB Hinshaw SP Kraemer HC Arnold LE Abikoff HB Cantwell DP Conners CK Elliott G Greenhill LL Hechtman L Hoza B Jensen PS March JS Newcorn JH Pelham WE Severe JB Swanson JM Vitiello B Wells KC Wigal T 《Journal of consulting and clinical psychology》2003,71(3):540-552
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. 相似文献
37.
Eight litters of hamsters living in a large enclosure were observed from birth to 120 days. For the first 65 days each litter was confined to a separate compartment. Basic motor coordination was reached by the 3rd week. Marking was seen during the 6th week when males began to mount their mothers sexually, but lordosis was not seen in female pups before the 7th week. Fighting appeared at this time with the females being the more aggressive. At 65 days the litters were combined into 2 groups of 4.A gradual shift followed in the relative aggressiveness of the sexes. Females, which had previously initiated over 90% of attacks, became less aggressive, whereas attacks by males increased to the former female level. This unusual behavior for hamsters, where females are normally dominant, may have been due to crowding. Also, severe disruption of maternal behavior occurred with marked infanticidal tendencies. 相似文献
38.
J. L. Hedrick K. Carter M. Sanchez R. Di Pietro S. Swanson S. Jayaraman J. G. McGrath 《Macromolecular chemistry and physics.》1997,198(2):549-559
A new route for the synthesis of high glass transition temperature, thermally stable polymer foams has been developed, using compositionally asymmetric microphase-separated block copolymers where the minor component (poly(propylene oxide)) is thermally labile and the major component (polyimide) is thermally stable. The minor component decomposes to low molecular weight species upon heating, and the decomposition products diffuse out of the film, leaving behind pores embedded in a matrix of the thermally stable component. In this study, the polyimide block was crosslinked with ethynyl functionalities to obtain a stable porous structure. The decomposition of the propylene oxide in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild conditions were required to avoid rapid depolymerization of the propylene oxide and plasticization of the polyimide matrix. The foams showed pore sizes with diameters up to a micrometer in size as well as the expected reduction in the mass density. 相似文献
39.
Antigen-binding peripheral blood lymphocytes in guinea-pigs immunized with human thyroglobulin in BCG 下载免费PDF全文
Guinea-pigs were immunized with an emulsion of human thyroglobulin (Tg) and BCG vaccine in Freund's incomplete adjuvant. Peripheral blood lymphocytes binding Tg and purified protein derivative of mammalian tuberculin (PPD) labelled with 125I were demonstrated with an autoradiographic technique. The percentage of these cells was compared with the size of the delayed hypersensitivity (DH) skin reactions to Tg and PPD, and Tg antibody titres at intervals up to 35 days after immunization. The individual responses to Tg showed the time course of primary immune reactions although they did not parallel each other closely. By contrast, a depression of cutaneous DH to PPD was observed in spite of the presence of substantial numbers of 125I-PPD-binding peripheral blood lymphocytes. In non-immune guinea-pigs, approximately 2·8% of peripheral blood lymphocytes bound 125I-PPD whereas <0·1% bound 125I-Tg.
The significance of antigen-binding lymphocytes in the immune response is discussed, and it is suggested that the presence of a substantial pool of antigen-binding lymphocytes in unprimed may be of importance in the induction of DH.
相似文献40.
Studies on gonococcus infection. XVI. Purification of Neisseria gonorrhoeae immunoglobulin A1 protease. 下载免费PDF全文
A protease which cleaves human immunoglobulin A1 (IgA1) has been purified from broth cultures of Neisseria gonorrhoeae. This IgA1 protease is produced by pilated and nonpilated gonococci throughout their growth cycles. A combination of ammonium sulfate precipitation, column chromatography, and either isoelectric focusing or affinity chromatography was utilized to obtain an enzyme preparation that showed approximately 3,800-fold purification and exhibited two bands (65,000 and 70,000 daltons) by analytical polyacrylamide electrophoresis in the presence of sodium dodecyl sulfate and reducing conditions. IgA1 protease activity is dependent on divalent cations and is heat labile. Detection and quantitation of IgA protease activity utilized an assay in which [125I]IgA1 is incubated with protease preparations and the cleavage products are analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 相似文献