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51.
M. Deckert-Schlüter Josef Marek Michael Šetlík Jana Marková E. Pakos Robert Fischer Otmar D. Wiestler 《Virchows Archiv : an international journal of pathology》1998,432(5):477-481
A 62-year-old woman presented with loss of memory and a mild hemiparesis. Neuroradiology demonstrated a left frontoparietal
tumour. Biopsy specimens of this lesion revealed intracerebral Hodgkin’s lymphoma, a diagnosis supported by immunohistochemical
reactions of the tumour cells for the CD30 antigen. Additional cell cycle studies revealed a high proliferative activity of
the tumour cells in association with absence of apoptosis. There was no evidence that overexpression of bcl-2 or Epstein-Barr
virus infection was involved in the pathogenesis of this neoplasm. Lymphomas in the lung were detected 3 months later. Following
neurosurgical excision, radiotherapy, and chemotherapy, the patient had no evidence of Hodgkin’s disease after 13 months of
follow-up.
Received: 8 October 1997 / Accepted: 8 December 1997 相似文献
52.
Miroslav Marek Michael Roman Danica Dosko
ilov Svatopluk Pokorný 《Macromolecular chemistry and physics.》1986,187(10):2337-2344
The polymerization of 3-chloro-2-methyl-1-propene was investigated at temperatures between 0 and ?80°C, using AlCl3 and AlBr3 as initiators. The molecular weights of the resulting oily products depend on the polymerization temperature and varied in the range of the number-average molecular weight M?n = 400–620. The course of polymerization was studied and the characteristic groupings in the oligomeris were identified by means of 1H NMR and 13C NMR spectroscopy. Based on the results the mechanism of partial reactions was discussed to explain the new type of propagation in the cationic polymerization. 相似文献
53.
Hauff K Zamzow C Law WJ De Melo J Kennedy K Los M 《Archivum immunologiae et therapiae experimentalis》2005,53(4):308-320
In this review we focus on peptide- and peptidomimetic-based approaches that target autoimmune diseases and some pathologies of the central nervous system. Special attention is given to asthma, allergic rhinitis, osteoarthritis, and Alzheimer's disease, but other related pathologies are also reviewed, although to a lesser degree. Among others, drugs like Diacerhein and its active form Rhein, Pralnacasan, Anakinra (Kineret), Omalizumab, an antibody "BION-1", directed against the common beta-chain of cytokine receptors, are described below as well as attempts to target beta-amyloid peptide aggregation. Parts of the review are also dedicated to targeting of pathologic conditions in the brain and in other tissues with peptides as well as methods to deliver larger molecules through the "blood--brain barrier" by exploring receptor-mediated transport, or elsewhere in the body by using peptides as carriers through cellular membranes. In addition to highlighting current developments in the field, we also propose, for future drug targets, the components of the inflammasome protein complex, which is believed to initiate the activation of caspase- 1 dependent signaling events, as well as other pathways that signal inflammation. Thus we discuss the possibility of targeting inflammasome components for negative or positive modulation of an inflammatory response. 相似文献
54.
Sowiska-Klencka D Klencki M Dedecjus M Lewiski A Pawlikowski M 《Endocrine pathology》2000,11(2):173-178
Nucleolar organizer regions (NORs) are segments of DNA, encoding for ribosomal RNA. They are associated with argyrophilic
proteins and, thus, they can be localized through silver staining. A correlation has been shown between the number, the size,
or the intranuclear localization of AgNORs, and the proliferative activity of cells. The aim of this study was to examine
numerous features of AgNORs in pituitary adenomas and to relate them to immunohistochemical typing of tumor. Histologic slides
from 32 pituitary tumors and one normal pituitary were silver-stained and analyzed with a computerized system for microscopic
image analysis, supported by an AgNORmeter95 program. All the tumors were also immunocyto chemically characterized. We have
found that gonadotropinomas, when compared with plurihormonal adenomas, revealed a lower proportion of nuclei with a single
AgNOR and a higher percentage of marginal dots. Recurrent adenomas, when compared with primary adenomas, showed a higher proportion
of nuclei with three AgNOR dots, a larger total area of dots in the nuclei, and a higher standard deviation of the AgNOR dot
area in the nucleus. Adenomas immunopositive for prolactin, when compared with immunonegative ones, showed a larger mean area
of the AgNOR dot, a larger area of the biggest dot in the nucleus, and a higher proportion of nuclei within a single dot.
These results suggest that the estimated parameters of AgNOR dots differ according to tumor aggressiveness and to the hormone
immunopositivity of pituitary adenomas. 相似文献
55.
Dina Marek‐Yagel Yoav Bolkier Ortal Barel Amir Vardi David Mishali Uriel Katz Yishay Salem Shachar Abudi Omri Nayshool Nitzan Kol Annick Raas‐Rothschild Gideon Rechavi Yair Anikster Ben Pode‐Shakked 《American journal of medical genetics. Part A》2020,182(5):987-993
The genetic basis of congenital heart malformations associated with disruption of left–right (L–R) asymmetry is broad and heterogenous, with variants in over 25 genes implicated thus far. Of these, deleterious variants in the Growth/Differentiation Factor 1 (GDF1) gene have been shown to cause heterotaxy with varied complex heart malformations of left–right patterning, in 23 individuals reported to date, either in monoallelic or biallelic state. We report three unrelated individuals exhibiting right isomerism with congenital heart defects, each originating from a consanguineous kindred of Arab‐Muslim descent. Using whole exome sequencing, a shared novel homozygous truncating c.608G > A (p.W203*) variant in the GDF1 gene was revealed as the molecular basis of their disease. Subsequently, targeted sequencing of this variant showed full segregation with the disease in these families, with a total of over 15 reportedly affected individuals, enabling genetic counseling, prenatal diagnosis, and planning of future pregnancies. Our findings further confirm the association of biallelic GDF1 variants, heterotaxy and congenital heart defects of left–right patterning, and expand the previously described phenotypic spectrum and mutational profile. Moreover, we suggest targeted screening for the p.W203* variant in relevant clinical circumstances. 相似文献
56.
An investigation was made on the effect of some n-alkyl halides (n-butyl fluoride, n-butyl chloride, and n-butyl bromide) and some benzyl halides (benzyl fluoride, benzyl chloride, and benzyl bromide) on the polymerization of isobutene in heptane, catalyzed by aluminium iodide. It was found that n-butyl fluoride and benzyl halides raise the rate of polymerization considerably. It was also established, from the dependence of the rate of polymerization and of the molecular weights on the concentration of alkyl halides and aluminium iodide, that alkyl halides do not act as cocatalysts, but that the increase in the rate of polymerization is due to the formation of catalytically active products of halogen exchange between aluminium iodide and alkyl halides. The results are discussed in terms of our present knowledge concerning the polymerization of isobutene with catalytic systems consisting of two FRIEDEL-CRAFTS halides. 相似文献
57.
Sadowy E Zhou J Meats E Gniadkowski M Spratt BG Hryniewicz W 《Microbial drug resistance (Larchmont, N.Y.)》2003,9(1):81-86
Multilocus sequence typing (MLST) of 35 isolates of multidrug-resistant Streptococcus pneumoniae recovered in Poland during 1995-1996 distinguished 10 different sequence types (ST). The majority of the isolates were assigned to two Polish clones of serotypes 6B and 23F, although the international clones, Spain23F-1 and Spain9V-3, were also identified. Similar results were obtained using pulsed-field gel electrophoresis (PFGE), providing a direct comparison of these two typing methods. 相似文献
58.
Jean -Marc Bollag Marek Duszota 《Archives of environmental contamination and toxicology》1984,13(3):265-270
Live and dead cells of several strains of bacteria as well as different microbial populations isolated from natural environments were tested for their ability to sorb cadmium (Cd) from a liquid medium (0.05M phosphate buffer, pH 7.2) containing 10 g Cd/ml. The bacterial cultures were grown in a nutrient solution without Cd, harvested, and then suspended in the buffer solution for the uptake assays. The amount of Cd sorbed by dead cells was usually higher than by live cells. Killing of bacteria by chemicals (ethanol, formaldehyde, or propylene oxide) or physical (-radiation) means had a varying effect on Cd uptake by dead cells. Various bacterial strains showed different degrees of resistance to Cd and different uptake levels of this heavy metal with no established correlation. Neither storage of the cells at 4°C for 48 hr after harvesting nor varying incubation times of the bacteria before the Cd uptake experiments had any influence on the amount of Cd sorbed.Paper No. 6609 of the Journal Series of the Agricultural Experiment Station, Pennsylvania State University, University Park, PA 16802 相似文献
59.
PurposeLate-diagnosed dislocated hips underwent open reduction, Dega osteotomy, and proximal femoral osteotomy between 1968 and 1988. The objectives of this study are to assess the survival of hips into adulthood, clinical and radiological outcome, patients’ life perspectives and the risk factors of failure.MethodsAn assessment of 67 hips treated when younger than five years (<age 5yr. group) and 71 hips in the group aged older than five years (+age 5yr.) was performed. All cases were evaluated clinically and radiographically, and survival was assessed, considering hip replacement as endpoints for failure (abbreviation HR+ refers to hips that underwent hip replacement surgery; HR- refers to hips that have not been replaced at the follow-up). The fertility rate and the social security disability benefits (SSDB) recipiency percentage were calculated.ResultsThe 40-year survival rates were 73% (95% confidence (CI) 71% to 76%) in the <age 5yr. group, 54% (95% CI 51% to 57%) in the +age 5yr. group, 70% (95% CI 67% to 73%) in one-sided dislocations and 57% (95% CI 54% to 60%) in bilateral dislocations. At follow-up, the median Harris hip and Western Ontario and McMaster Universities Osteoarthritis scores were 90.0 and 13.0 (<age 5yr. group, HR-), 74.0 and 28.0 (+age 5yr. group, HR-), 90.0 and 16.0 (<age 5yr. group, HR+) and 84.5 and 11.5 (+age 5yr. group, HR+), respectively. The operation normalized the radiological parameters. The correlation between the grade of femoral head avascular necrosis (AVN) at a median 2.6 years after the operation and the grade of osteoarthritis at follow-up was 0.38 (p < 0.001). The fertility rate was 1.54. In total, 16.0% (aged under five years) and 38.5% (aged over five years) of patients were receiving SSDB (p = 0.003).ConclusionEarly failure risk factors are older age at the surgical procedure, high AVN grade and bilateral hip involvement. Still, the results facilitate hip reposition whenever technically manageable, even in teenagers.Level of evidenceIII 相似文献
60.