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41.
Patterns of cytokine gene expression in peripheral T-cell lymphoma of angioimmunoblastic lymphadenopathy type 总被引:3,自引:0,他引:3
Foss HD; Anagnostopoulos I; Herbst H; Grebe M; Ziemann K; Hummel M; Stein H 《Blood》1995,85(10):2862-2869
42.
The effects on the fertility of adult male rats of six new synthetic steroids: I, 3-cyano-5alpha-androst-1-en-17-one; II, the 17beta-acetate form of I; III, 17beta-hydroxy-5beta-cyano-androstan-3-one; IV, 6-methylpregnenolone; V, 17beta-hydroxy-17alpha-ethynyl-5beta-cyano-19-norandrostan-3-one; and VI, 19-norspiroxenone (oestr-4-en-3-one-spiro-17alpha-2'-[tetrahydrofuran]) have been tested. After 6 weeks of treatment with daily doses of 5 mg (I, II, III), 15 mg (IV) or 10 mg (V, VI) only steroid VI blocked the completion of spermatogenesis and reduced the number of foetuses sired in at least five females/male. Steroid VI also diminished seminal vesicular, prostatic, testicular and epididymal weights. It inhibited the testicular enzymes, 3beta-hydroxysteroid dehydrogenase-delta4-5-3-oxosteroid isomerase system, 17alpha-hydroxylase, and C17-20 lyase markedly, but did not affect the adrenal dehydrogenase-isomerase system. It depressed, strikingly, testicular and serum levels of testosterone and 5alpha-dihydrotestosterone and reduced pituitary and serum levels of FSH and LH. Although marked depression of target organ weights also occurred with steroids II, IV and V, and reduction of androgen levels and LH in the circulation with III, IV and V, only VI was a potent blocker of male fertility with the exception of a slight block of the siring of viable foetuses by steroids IV and V. The major difference in site of action of steroid VI from the others was the depression of pituitary and serum levels of FSH along with a marked diminution of testicular content of both testosterone and 5alpha-dihydrotestosterone. 19-Norspiroxenone in the rat is a potent anti-oestrogen without inherent oestrogenicity and is anti-uterotrophic. Thus, VI may affect male fertility by virtue of its potent anti-oestrogenic action in the hypothalamus or testis. 相似文献
43.
D R Park V L Sherbin M S Goodman A D Pacifico G D Rubenfeld N L Polissar R K Root 《The Journal of infectious diseases》2001,184(3):268-277
In a prospective study, the etiology of community-acquired pneumonia (CAP) was investigated among consecutive patients admitted to an academic, urban public hospital in Seattle. The study population was uniquely young, was predominantly male, and had high rates of homelessness, cigarette smoking, alcoholism, injection drug use, and human immunodeficiency virus (HIV) infection. Leading causes of CAP among HIV-negative patients were aspiration, followed by Streptococcus pneumoniae, Legionella species, and Mycoplasma pneumoniae. Among HIV-positive patients, Pneumocystis carinii, Mycobacterium tuberculosis, S. pneumoniae, and M. pneumoniae were the most common etiologic agents. Severe CAP was associated with typical bacterial infections and aspiration pneumonia but not Legionella infection among HIV-negative patients and with Pseudomonas aeruginosa infections among HIV-positive patients. These findings emphasize the need to tailor empirical antibiotic therapy according to local patient populations and individual risk factors and highlight the importance of recognizing underlying HIV infection in patients who are hospitalized with CAP. 相似文献
44.
von den Driesch P; Bhardwaj R; Flad HD; Neugebauer DC; Pielken HJ; Urbanitz D; Kolsch E 《Blood》1989,74(1):430-436
An immunoglobulin M (IgM)-positive cell line, Ms 28, apparently spontaneously transformed by Epstein-Barr virus (EBV) was established from peripheral blood cells of a patient with immature myeloblastic leukemia. It has been characterized according to phenotype, cytochemistry, and membrane antigen pattern. The cell line expresses lymphoid markers like CD 19, CD 22, and CD 30 and synthesizes and secretes IgM. Monocyte markers CD 11c, CD 14, and CD 15 are absent. Neither interleukin-1 (IL-1), nor tumor necrosis factor (TNF-alpha) are produced. But Ms 28 cells show strong phagocytic activity and engulf Latex particles and sheep RBCs (SRBCs) that need not to be opsonized. The phagocytic activity can be inhibited by chloroquine. Both phagocytosis and EBV nuclear-antigen (EBNA) expression can be observed in one and the same cell. Ms 28 cells might be useful to study immunologic activities like antigen processing and presentation. 相似文献
45.
Regionally selective atrophy of subcortical structures in prodromal HD as revealed by statistical shape analysis
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Laurent Younes J. Tilak Ratnanather Timothy Brown Elizabeth Aylward Peg Nopoulos Hans Johnson Vincent A. Magnotta Jane S. Paulsen Russell L. Margolis Roger L. Albin Michael I. Miller Christopher A. Ross PREDICT‐HD Investigators Coordinators of the Huntington Study Group 《Human brain mapping》2014,35(3):792-809
Huntington disease (HD) is a neurodegenerative disorder that involves preferential atrophy in the striatal complex and related subcortical nuclei. In this article, which is based on a dataset extracted from the PREDICT‐HD study, we use statistical shape analysis with deformation markers obtained through “Large Deformation Diffeomorphic Metric Mapping” of cortical surfaces to highlight specific atrophy patterns in the caudate, putamen, and globus pallidus, at different prodromal stages of the disease. On the basis of the relation to cortico‐basal ganglia circuitry, we propose that statistical shape analysis, along with other structural and functional imaging studies, may help expand our understanding of the brain circuitry affected and other aspects of the neurobiology of HD, and also guide the most effective strategies for intervention. Hum Brain Mapp 35:792–809, 2014. © 2012 Wiley Periodicals, Inc. 相似文献
46.
Paul Root Wolpe 《The Hastings Center report》2020,50(4):3-3
Over time, ethical judgments evolve, but so do the phenomena they are applied to. For example, plagiarism is a modern concept. Before the early eighteenth century, works did not generally have references or acknowledgments, and ideas were freely exchanged. As writing became an occupation, copying others' words became “unethical.” As cut and paste, music mash-up, and other technological forms of exchange make copying the works of others simple, the idea of plagiarism is eroding, and perhaps will eventually even be discarded. The same may be true with privacy. As with plagiarism, it was not really until the eighteenth century that our modern idea of privacy was established. To younger generations, raised on social media, online life is predicated on trading personal information for access. The undermining of former standards of privacy may suggest that privacy may also eventually become an outmoded concept. 相似文献
47.
构建Loa22基因去信号肽片段原核重组表达载体 总被引:1,自引:0,他引:1
目的:构建赖型钩端螺旋体OmpA膜蛋白Loa22基因去信号肽片段的原核表达载体,并对其进行克隆表达。方法:实验于2004—12/2005—12在四川大学华西医学中心感染免疫研究室完成。以赖型钩端螺旋体017株基因组DNA为模板,PCR扩增Loa22基因去信号肽片段,亚克隆至原核表达载体pGEX-4T-1,经双酶切、PCR鉴定,筛选出阳性重组质粒克隆。经DNA测序正确后,转化大肠杆菌,利用IPTG进行诱导表达,通过SDS—PAGE鉴定表达产物。结果:PCR获得长516bp的片段。Loa22基因去信号肽片段与pGEX-4T-1的重组质粒构建成功。重组质粒经IPTG诱导后能在大肠杆菌中表达Mr45000的融合蛋白。结论:制备了Loa22基因去信号肽片段原核重组表达载体,为钩体新型疫苗的研究奠定基础。 相似文献
48.
Large‐scale brain network abnormalities in Huntington's disease revealed by structural covariance
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Lora Minkova Simon B. Eickhoff Ahmed Abdulkadir Christoph P. Kaller Jessica Peter Elisa Scheller Jacob Lahr Raymund A. Roos Alexandra Durr Blair R. Leavitt Sarah J. Tabrizi Stefan Klöppel TRACK‐HD Investigators 《Human brain mapping》2016,37(1):67-80
Huntington's disease (HD) is a progressive neurodegenerative disorder that can be diagnosed with certainty decades before symptom onset. Studies using structural MRI have identified grey matter (GM) loss predominantly in the striatum, but also involving various cortical areas. So far, voxel‐based morphometric studies have examined each brain region in isolation and are thus unable to assess the changes in the interrelation of brain regions. Here, we examined the structural covariance in GM volumes in pre‐specified motor, working memory, cognitive flexibility, and social‐affective networks in 99 patients with manifest HD (mHD), 106 presymptomatic gene mutation carriers (pre‐HD), and 108 healthy controls (HC). After correction for global differences in brain volume, we found that increased GM volume in one region was associated with increased GM volume in another. When statistically comparing the groups, no differences between HC and pre‐HD were observed, but increased positive correlations were evident for mHD, relative to pre‐HD and HC. These findings could be explained by a HD‐related neuronal loss heterogeneously affecting the examined network at the pre‐HD stage, which starts to dominate structural covariance globally at the manifest stage. Follow‐up analyses identified structural connections between frontoparietal motor regions to be linearly modified by disease burden score (DBS). Moderator effects of disease load burden became significant at a DBS level typically associated with the onset of unequivocal HD motor signs. Together with existing findings from functional connectivity analyses, our data indicates a critical role of these frontoparietal regions for the onset of HD motor signs. Hum Brain Mapp 37:67–80, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
49.
50.
Hypercalciuria, hyperphosphaturia, and growth retardation in children with diabetes mellitus 总被引:1,自引:0,他引:1
The role of hypercalciuria and hyperphosphaturia in the growth retardation of children with diabetes mellitus was investigated in 157 children with diabetes whose mean height was less than that of 37 nondiabetic siblings of similar age (P less than .025). Hyperglycemia, hypercalciuria, and hyperphosphaturia were assessed coincident with the height measurement of each child in a cross-sectional survey. The distribution of height percentiles of the children with diabetes was skewed to the left with 61% at or below the 50th percentile. Eleven percent of the insulin-dependent children with diabetes mellitus were shorter than would be anticipated by a normal distribution of the 157 children. The duration of diabetes (hyperglycemia) had the greatest influence upon the children's height. Children with diabetes were shorter than the nondiabetic subjects by the fourth year of hyperglycemia, and this difference in height became statistically significant after 7 years or more of diabetes. The degree of hypercalciuria and hyperphosphaturia was more closely associated with reduced height in children with diabetes than was the degree of hyperglycemia, although the renal wastage of calcium and phosphorus seemed to be the result of glucosuria. Because hypercalciuria and hyperphosphaturia impair growth in nondiabetic children, they may also play an important role in the poor growth of children with diabetes mellitus. 相似文献