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31.
W G Hocking  M Swanson 《Cancer》1986,58(4):840-842
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   
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33.
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.
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  
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.
We studied 68 sporadic colorectal carcinomas (CRCs) with medullary features (MCRCs) and compared them with 35 poorly differentiated purely "enteric" CRCs (ECRCs) and 15 purely neuroendocrine carcinomas (NECs) of grades II and III, all in patients lacking a family history of CRC. Potential clinicopathologic differences between the study groups were assessed. MCRCs were significantly more common in the ascending colon than were ECRCs, but there was no significant dissimilarity to NECs. ECRCs occurred more often in the rectosigmoid than MCRCs or NECs. MCRCs arose in older patients, and a marked sex difference also was noted. Despite an infiltrative growth pattern, MCRC was less likely than ECRC to manifest with stage III or IV disease, but there was no stage-related difference from NECs. Although the histologic images of MCRCs were evocative of neuroendocrine differentiation, chromogranin positivity and synaptophysin reactivity in that group did not differ meaningfully from that of ECRCs but was dissimilar to the 100% labeling of NECs. p53 immunolabeling was similar in the 3 tumor groups. Follow-up data in the study cases showed that 5-year mortality was 40% (27/68) for MCRC, 59% (19/32) for ECRC, and 93% (14/15) for NEC. Medullary CRC seems to be a distinct clinicopathologic variant of CRC, which does not have a neuroendocrine lineage. The biologic behavior of MCRC was better than that of ECRC or NEC.  相似文献   
37.
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   
38.
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   
39.
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   
40.
The performance of the LCx HIV RNA Quantitative (LCx HIV), AMPLICOR HIV-1 MONITOR version 1.5 (MONITOR v1.5), and Quantiplex HIV-1 RNA version 3.0 (bDNA v3.0) viral load assays was evaluated with 39 viral isolates (3 A, 7 B, 6 C, 4 D, 8 E, 4 F, 1 G, 4 mosaic, and 2 group O). Quantitation across the assay dynamic ranges was assessed using serial fivefold dilutions of the viruses. In addition, sequences of gag-encoded p24 (gag p24), pol-encoded integrase, and env-encoded gp41 were analyzed to assign group and subtype and to assess nucleotide mismatches at primer and probe binding sites. For group M isolates, quantification was highly correlated among all three assays. In contrast, only the LCx HIV assay reliably quantified group O isolates. The bDNA v3.0 assay detected but consistently underquantified group O viruses, whereas the MONITOR v1.5 test failed to detect group O viruses. Analysis of target regions revealed fewer primer or probe mismatches in the LCx HIV assay than in the MONITOR v1.5 test. Consistent with the high level of nucleotide conservation is the ability of the LCx HIV assay to quantify efficiently human immunodeficiency virus type 1 group M and the genetically diverse group O.  相似文献   
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