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11.
A high proportion of the antibodies in the preimmune repertoire bind to several unrelated antigens and are considered to be multireactive. This property is reportedly associated with the antibodies produced by CD5+ B lymphocytes. Because many antibodies specific for bromelain-treated mouse red blood cells (BrMRBC) derive from CD5+ B cells, we tested monoclonal antibodies of this specificity for multireactivity. Two variable region combinations, VH11/V kappa 9 and VH12/V kappa 4, account for greater than 80% of this repertoire, but none of these antibodies exhibited a multireactive phenotype. In contrast, three anti-BrMRBC binding antibodies belonging to the J558 family (BrM1, BrM8, and CH12) showed varying degrees of multireactivity, and bound both highly negatively and positively charged antigens. The amino acid sequences of the VH regions of these antibodies are highly homologous (greater than 85% identical) and they possess large VH-D-J junctions with extensive N-region insertions. The kappa chains of two of these antibodies utilize an identical V kappa gene segment, while the third uses a very different V kappa with only 50% homology. The entire H chain V regions of these antibodies are unusually basic, with isoelectric points of 9.5-10, a feature which might be important in promoting interactions with acidic epitopes. The multireactive antibodies also contain regions with a high concentration of hydroxylside chain amino acids, especially in their VH-D-J junctions. This region also contains acidic amino acid residues, which may be important in binding of positively charged epitopes. We propose that an open, accessible binding site and a charge polarity may be features which facilitate the binding of charged epitopes, providing a structural basis for multireactivity of at least some antibodies. 相似文献
12.
13.
Man-in-the-barrel syndrome 总被引:2,自引:0,他引:2
In a prospective study of 34 comatose patients who had an episode of systemic hypotension, 11 had the "man-in-the-barrel" syndrome (MIB). They moved both legs spontaneously or in response to pain, but did not move either arm. One of 11 patients (9%) with MIB survived to leave the hospital; 8 of the 23 patients (35%) without MIB recovered. Of patients who moved at least one limb to pain and had intact pupillary, corneal, and oculocephalic reflexes 24 hours after insult, one of nine (11%) patients with MIB survived, compared with six of nine patients (67%) without MIB. MIB is common after cerebral hypoperfusion and carries a poor prognosis. 相似文献
14.
We report the clinical course of 35 patients with Parkinson's disease who experienced an initially favorable response to pergolide and who were taking the drug for at least 6 months. The duration of pergolide treatment was 6-50 (25 +/- 16 SD) months. Of the 14 patients who remained on pergolide for over 2 years, 12 remained less disabled for 26 +/- 17 SD months, seven enjoyed increased "on" time for 39 +/- 8 SD months, and nine had a lower Hoehn-Yahr stage for 25 +/- 17 SD months. Pergolide was discontinued after 5-39 months in eight patients; six patients then deteriorated. Pergolide can remain efficacious in the treatment of Parkinson's disease for up to 50 months. 相似文献
15.
目的 探讨盐酸喹那普利 (QuinaprilHydrochloride)治疗轻、中度原发性高血压的有效性和安全性。方法 全国 6家医院参加的一项多中心、随机、双盲、平行组间对照研究。结果 113例原发性高血压病人治疗 8周后 ,总有效率达 85 84% ,统计学有显著性差异。盐酸喹那普利副反应较轻 ,对肾脏、肝脏、造血系统和心脏未见有害作用。结论 盐酸喹那普利是一种安全、疗效好、副反应小的治疗轻、中度原发性高血压的有效药物。 相似文献
16.
Gilbert RE Cox AJ Kelly DJ Wilkinson-Berka JL Sage EH Jerums G Cooper ME 《Connective tissue research》1999,40(4):295-303
Secreted protein acidic and rich in cysteine (SPARC) is a secreted glycoprotein protein which modulates cell shape and cell-matrix interactions and has been implicated in the regulation of angiogenesis, vascular permeability and cataract formation. In situ hybridization and immunohistochemical studies for SPARC were performed to determine the cell and tissue distribution of SPARC in rat eye. Studies demonstrated SPARC mRNA and protein co-localization at all sites. In the retina SPARC mRNA and protein were localized predominantly to the Müller and ganglion cells. Within the choroid, SPARC was found in vascular endothelial cells and fibroblasts; in the sclera SPARC was present in blood vessels and fibroblasts. SPARC was also present in the non-pigmented epithelial cells of the ciliary body, and in the epithelium of the lens capsule and cornea. The demonstrated anatomical distribution of SPARC in the rat eye is consistent with several of the biological functions ascribed to this matricellular protein and provides a rational basis for its examination in pathological conditions. 相似文献
17.
Mutagenic specificity of solar UV light in nucleotide excision repair-deficient rodent cells.
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E Sage B Lamolet E Brulay E Moustacchi A Chteauneuf E A Drobetsky 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(1):176-180
To investigate the role of nucleotide excision repair (NER) in the cellular processing of carcinogenic DNA photoproducts induced by defined, environmentally relevant portions of the solar wavelength spectrum, we have determined the mutagenic specificity of simulated sunlight (310-1100 nm), UVA (350-400 nm), and UVB (290-320 nm), as well as of the "nonsolar" model mutagen 254-nm UVC, at the adenine phosphoribosyltransferase (aprt) locus in NER-deficient (ERCC1) Chinese hamster ovary (CHO) cells. The frequency distributions of mutational classes induced by UVB and by simulated sunlight in repair-deficient CHO cells were virtually identical, each showing a marked increase in tandem CC-->TT transitions relative to NER-proficient cells. A striking increase in CC-->TT events was also previously documented for mutated p53 tumor-suppressor genes from nonmelanoma tumors of NER-deficient, skin cancer-prone xeroderma pigmentosum patients, compared to normal individuals. The data therefore indicate that the aprt gene in NER-deficient cultured rodent cells irradiated with artificial solar light generates the same distinctive "fingerprint" for sunlight mutagenesis as the p53 locus in NER-deficient humans exposed to natural sunlight in vivo. Moreover, in strong contrast to the situation for repair-component CHO cells, where a significant role for UVA was previously noted, the mutagenic specificity of simulated sunlight in NER-deficient CHO cells and of natural sunlight in humans afflicted with xeroderma pigmentosum can be entirely accounted for by the UVB portion of the solar wavelength spectrum. 相似文献
18.
Efficient allocation of resources is essential in any activity, but experimenting to determine appropriate levels risks a reduction in services that could be dangerous in a healthcare operation. Computer simulations offer a risk-free environment for testing alternate resource levels and balancing costs and services. This article describes the use of a simulation to determine appropriate staffing levels for an emergency medical service. 相似文献
19.
We present data collected from two anomic aphasics. Thorough assessment of comprehension, oral reading and repetition revealed no underlying impairments suggesting that both patients were examples of classical anomia--word-finding difficulties without impaired semantics or phonology. We describe a series of experiments in which the degree of anomia was both increased and decreased, by cueing or priming with either a semantically related word or the target item. One of the patients also presented with an 'acquired' tip-of-the-tongue phenomenon. He was able to indicate with a high-degree of accuracy the syllable length of the target, and whether or not it was a compound word. Neither patient could provide the first sound/letter. The data are discussed in terms of discrete two-stage models of speech production, an interactive-activation theory and a distributed model in which the positive and negative computational consequences of the arbitrary relationship between sound and meaning are emphasised. 相似文献
20.
Ramon Pathi Michael Sage John Slavotinek Ahmad Hanieh 《Journal of Medical Imaging and Radiation Oncology》2004,48(1):61-63
A case of an abdominal cerebrospinal fluid (CSF) pseudocyst in a patient with a ventriculoperitoneal shunt is reported to illustrate this known but rare complication. In the setting of a VP shunt, the frequency of abdominal CSF pseudocyst formation is approximately 3.2%, often being precipitated by a recent inflammatory or infective process or recent surgery. Larger pseudocysts tend to be sterile, whereas smaller pseudocysts are more often infected. Ultrasound and CT each have characteristic findings. 相似文献