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991.
The nature of the heat precipitation of 3 mononoclonal heat labile immunoglobulins was studied. These included 2 γG pyroglobulins and one γM pyroglobulin. Thermoprecipitable activity of both γG pyroglobulins could be localized to their heavy chains and to the Fab fragments of one of them. Heat precipitability of the γM paraprotein required the presence of the intact γM molecule since 7S subunits did not precipitate. The thermal precipitates appeared to result from intramolecular or intermolecular reactions with the formation of strong covalent bonds rather than weak non-covalent bonds. The importance of disulphide bonding was excluded in the precipitation of both γG but not in the γM pyroglobulins. Heat precipitation of the monoclonal γM resulted in coprecipitation of other proteins, particularly γG globulin, which suggested a specific type of reaction with this immunoglobulin. The interaction of the γM pyroglobulin, normal γG and heat produced an irreversible precipitate. 相似文献
992.
Beasley MB Franks TJ Galvin JR Gochuico B Travis WD 《Archives of pathology & laboratory medicine》2002,126(9):1064-1070
CONTEXT: The histologic patterns of diffuse alveolar damage (DAD), bronchiolitis obliterans with organizing pneumonia (BOOP), and eosinophilic pneumonia (EP) are well-recognized histologic patterns of lung injury associated with an acute or subacute clinical presentation. We have recognized acute fibrinous and organizing pneumonia (AFOP) as a histologic pattern, which also occurs in this clinical setting but does not meet the classic histologic criteria for DAD, BOOP, or EP and may represent an underreported variant. OBJECTIVE: To investigate the clinical significance of the AFOP histologic pattern and to explore its possible relationship to other disorders, including DAD and BOOP. DESIGN: Open lung biopsy specimens and autopsy specimens were selected from the consultation files of the Armed Forces Institute of Pathology, which showed a dominant histologic pattern of intra-alveolar fibrin and organizing pneumonia. Varying amounts of organizing pneumonia, type 2 pneumocyte hyperplasia, edema, acute and chronic inflammation, and interstitial widening were seen. Cases with histologic patterns of classic DAD, BOOP, abscess formation, or eosinophilic pneumonia were excluded. To determine the clinical behavior of patients with this histologic finding, clinical and radiographic information and follow-up information were obtained. Statistical analysis was performed using Kaplan-Meier and chi(2) analysis. RESULTS: Seventeen patients (10 men, 7 women) with a mean age of 62 years (range, 33-78 years) had acute-onset symptoms of dyspnea (11), fever (6), cough (3), and hemoptysis (2). Associations believed to be clinically related to the lung disease included definitive or probable collagen vascular disease (3), amiodarone (1), sputum culture positive for Haemophilus influenza (1), lung culture positive for Acinetobacter sp. (1), lymphoma (1), hairspray (1), construction work (1), coal mining (1), and zoological work (1). Six patients had no identifiable origin or association. Follow-up revealed 2 clinical patterns of disease progression: a fulminate illness with rapid progression to death (n = 9; mean survival, 0.1 year) and a more subacute illness, with recovery (n = 8). Histologic analysis and initial symptoms did not correlate with eventual outcome, but 5 of the 5 patients who required mechanical ventilation died (P =.007). CONCLUSIONS: Acute fibrinous and organizing pneumonia is a histologic pattern associated with a clinical picture of acute lung injury that differs from the classic histologic patterns of DAD, BOOP, or EP. Similar to these patterns of acute lung injury, the AFOP pattern can occur in an idiopathic setting or with a spectrum of clinical associations. The overall mortality rate is similar to DAD and therefore may represent a histologic variant; however, AFOP appears to have 2 distinct patterns of disease progression and outcome. The need for mechanical ventilation was the only parameter that correlated with prognosis. None of the patients with a subacute clinical course required mechanical ventilation. 相似文献
993.
Effect of risedronate on the risk of hip fracture in elderly women. Hip Intervention Program Study Group 总被引:34,自引:0,他引:34
McClung MR Geusens P Miller PD Zippel H Bensen WG Roux C Adami S Fogelman I Diamond T Eastell R Meunier PJ Reginster JY;Hip Intervention Program Study Group 《The New England journal of medicine》2001,344(5):333-340
BACKGROUND: Risedronate increases bone mineral density in elderly women, but whether it prevents hip fracture is not known. METHODS: We studied 5445 women 70 to 79 years old who had osteoporosis (indicated by a T score for bone mineral density at the femoral neck that was more than 4 SD below the mean peak value in young adults [-4] or lower than -3 plus a nonskeletal risk factor for hip fracture, such as poor gait or a propensity to fall) and 3886 women at least 80 years old who had at least one nonskeletal risk factor for hip fracture or low bone mineral density at the femoral neck (T score, lower than -4 or lower than -3 plus a hip-axis length of 11.1 cm or greater). The women were randomly assigned to receive treatment with oral risedronate (2.5 or 5.0 mg daily) or placebo for three years. The primary end point was the occurrence of hip fracture. RESULTS: Overall, the incidence of hip fracture among all the women assigned to risedronate was 2.8 percent, as compared with 3.9 percent among those assigned to placebo (relative risk, 0.7; 95 percent confidence interval, 0.6 to 0.9; P=0.02). In the group of women with osteoporosis (those 70 to 79 years old), the incidence of hip fracture among those assigned to risedronate was 1.9 percent, as compared with 3.2 percent among those assigned to placebo (relative risk, 0.6; 95 percent confidence interval, 0.4 to 0.9; P=0.009). In the group of women selected primarily on the basis of nonskeletal risk factors (those at least 80 years of age), the incidence of hip fracture was 4.2 percent among those assigned to risedronate and 5.1 percent among those assigned to placebo (P=0.35). CONCLUSIONS: Risedronate significantly reduces the risk of hip fracture among elderly women with confirmed osteoporosis but not among elderly women selected primarily on the basis of risk factors other than low bone mineral density. 相似文献
994.
xlgv7: a maternal gene product localized in nuclei of the central nervous system in Xenopus laevis 总被引:8,自引:0,他引:8
The Xenopus oocyte nucleus (GV) is a storehouse for a large number of proteins that are used during early development. We have cloned and characterized a cDNA coding for a maternal gene product that is localized in the GV and then becomes highly enriched in the nuclei of the central nervous system (CNS) of tadpoles and adult frogs. This cDNA (xlgv7) is 2.1 kb and hybridizes to a 2.4-kb RNA species on Northern blots. Southern blots of genomic DNA suggest that this gene is a member of a multigene family. The cDNA sequence reveals a long open reading frame (ORF) of 1773 nucleotides, with a putative nuclear targeting signal (Glu Arg Arg Lys Lys Lys Thr) at the extreme carboxyl terminus and an internal histidine (His)-rich region with a repeated conserved amino acid sequence between His pairs. The significance of this region is unclear, but the protein is a DNA-binding protein, and it is possible that this region is involved in this function. The xlgv7 protein also possesses a putative nucleotide-binding consensus sequence that is similar to the bacterial RecA and RecB and yeast RAD proteins. Protein xlgv7 exists as several isotypes that exhibit developmental and cell-specific changes during development. Northern blot analysis of the abundance of the xlgv7 mRNA shows an accumulation following neural induction at stages 15-16. There is a transient expression of the mRNA in the gut of tadpoles. In the adult, the mRNA is highly enriched in the brain and is absent or in very low abundance in other tissues. Immunohistochemical analysis of the protein shows that the protein is localized in the nuclei of the brain cells. We conclude that the xlgv7 gene product is a maternal protein that may serve several important functions, one of which may be in the development and maintanance of the CNS. 相似文献
995.
The development and evaluation of a measure of accurate empathy is described. The Helpful Responses Questionnaire (HRQ) is a brief free response questionnaire that can be administered to groups. Interrater reliability coefficients for items range from .71 to .91, and reliability for total HRQ scores was found to be .93. HRQ scores rose significantly following a 2-day workshop on active listening and crisis intervention skills offered in 14 communities. Normative data are reported based on a sample of 190 paraprofessional trainees. Level of empathy was found to be modestly related to respondents' self-esteem. 相似文献
996.
997.
A direct relationship between bronchodilator efficacy and toxicity by the measurement of serum theophylline concentrations is well established. This study evaluated, in children receiving either 12-hour (Theo-Dur) or an experimental 24-hour (Theo-Beads) preparation, the most common time to reach peak and trough levels in the serum. Twenty-three children with chronic asthma between the ages of 7 and 12 years participated in the study. Twelve received theophylline every 12 hours at a dose ranging from 400 to 800 mg per 24 hours. Eleven children received a 24-hour preparation at a dose ranging between 400 and 1000 mg per 24 hours. The results demonstrated no relationship between dosing interval and the appearance of peak or trough levels with Theo-Dur. Theo-Beads reached its peak in 9 to 11 children between six and eight hours and for 10 to 11 children the trough value was at the end of the dosing interval. 相似文献
998.
Echocardiographically documented mitral-valve prolapse. Long-term follow-up of 237 patients 总被引:5,自引:0,他引:5
R A Nishimura M D McGoon C Shub F A Miller D M Ilstrup A J Tajik 《The New England journal of medicine》1985,313(21):1305-1309
We determined the long-term prognosis for patients with mitral-valve prolapse documented by echocardiography by following 237 minimally symptomatic or asymptomatic patients for a mean of 6.2 years (range, 1 to 10.4). The actuarial eight-year probability of survival was 88 per cent, which is not significantly different from that for a matched control population. An initial left ventricular diastolic dimension exceeding 60 mm was the best echocardiographic predictor of the subsequent need for mitral-valve replacement (17 patients). Of the 97 patients with redundant mitral-valve leaflets identified echocardiographically, 10 (10.3 per cent) had sudden death, infective endocarditis, or a cerebral embolic event; in contrast, of the 140 patients with nonredundant valves, only 1 (0.7 per cent) had such complications (P less than 0.001). Most patients with echocardiographic evidence of mitral-valve prolapse have a benign course, but subsets at high risk for the development of progressive mitral regurgitation, sudden death, cerebral embolic events, or infective endocarditis can be identified by echocardiography. 相似文献
999.
Barbara L. Andersen Steven J. Beck Robert A. Bornstein Charles F. Emery Mary A. Fristad Janice K. Kiecolt-Glaser Daniel R. Strunk Julian F. Thayer Michael W. Vasey Keith O. Yeates 《Clinical psychology》2008,15(1):102-104
We review the methods in the ranking of clinical psychology doctoral programs provided by Stewart, Roberts, and Roy (2007). Using our own program as an example, we identify several areas of concern (e.g., authorship credits, criteria applied, faculty attrition). The inaccuracies identified for our program ranking, in combination with methodological concerns highlighted by previous commentaries, suggest that the validity of the rankings can be called into question. 相似文献
1000.
Kenneth Micklethwaite Anna Hansen Aaron Foster Elizabeth Snape Vicki Antonenas Mary Sartor Peter Shaw Ken Bradstock David Gottlieb 《Biology of blood and marrow transplantation》2007,13(6):707-714
Cytomegalovirus reactivation and infection post-allogeneic hematopoietic stem cell transplant continue to cause morbidity and mortality. Current pharmacologic therapies are limited by side effects. Adoptive transfer of ex vivo generated cytomegalovirus-specific T cells has the potential to restore immunity, prevent cytomegalovirus, and circumvent the need for pharmacologic therapies. We have generated donor-derived cytomegalovirus-specific cytotoxic T cells using dendritic cells pulsed with the HLA-A2 restricted nonapeptide NLVPMVATV (NLV) derived from the cytomegalovirus-pp65 protein. These cytotoxic T cells have been given prophylactically to 9 recipients aged 4 to 65 years on or after day 28 post-allogeneic hematopoietic stem cell transplant. Only 2 of 9 recipients received T cell depletion in vivo or in vitro. There were no immediate adverse reactions to the infusions. During 97-798 days of follow-up, 2 recipients developed cytomegalovirus reactivation; neither developed cytomegalovirus disease or required pharmacotherapy. Three recipients developed acute graft versus host disease after infusion. Two recipients died, 1 from thrombotic thrombocytopenia purpura secondary to cyclosporine, 1 from complications of graft versus host disease. A transient increase in numbers of cytomegalovirus-specific T cells demonstrated by NLV-tetramer binding was seen in 6 recipients. Prophylactic adoptive transfer of NLV-specific T cells is safe and may be effective in preventing cytomegalovirus reactivation. 相似文献