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排序方式: 共有670条查询结果,搜索用时 15 毫秒
91.
In recent years there has been a decline in the uptake of the MMR vaccine and a significant increase the number of reported case of mumps. This condition has number of important extrasalivary manifestations including mumps epididymo-orchitits. The article reviews the pathophysiology, clinical symptoms, diagnosis, and long-term sequelae of this increasingly prevalent condition and provides a reference for all practising urologists treating this disease. 相似文献
92.
Ian R. Humphreys Mathew Clement Morgan Marsden Kristin Ladell James E. McLaren Kathryn Smart James P. Hindley Hayley M. Bridgeman Hugo A. van den Berg David A. Price Ann Ager Linda Wooldridge Andrew Godkin Awen M. Gallimore 《European journal of immunology》2012,42(12):3235-3242
Decline of cell‐mediated immunity is often attributed to decaying T‐cell numbers and their distribution in peripheral organs. This study examined the hypothesis that qualitative as well as quantitative changes contribute to the declining efficacy of CD8+ T‐cell memory. Using a model of influenza virus infection, where loss of protective CD8+ T‐cell immunity was observed 6 months postinfection, we found no decline in antigen‐specific T‐cell numbers or migration to the site of secondary infection. There was, however, a large reduction in antigen‐specific CD8+ T‐cell degranulation, cytokine secretion, and polyfunctionality. A profound loss of high‐avidity T cells over time indicated that failure to confer protective immunity resulted from the inferior functional capacity of remaining low avidity cells. These data imply that high‐avidity central memory T cells wane with declining antigen levels, leaving lower avidity T cells with reduced functional capabilities. 相似文献
93.
The efficacy and outcome of bone marrow transplantation therapy following lethal irradiation were examined in syngeneic mice that had a hereditary macrocytic anemia (an/an) or were genotypically normal (+/+). Successful RBC and WBC replacement, based on blood cell parameters and donor genetic markers, were observed in all combinations of transplant therapy. Nevertheless, the an/an mice died prematurely several months after treatment, whether they received +/+ or an/an marrow cells. In contrast, the +/+ recipients of either +/+ or an/an marrow cells survived for at least 1 year after transplantation. Premature death of the an/an mice was associated with lymphopenia, anemia, kidney lesions, and severe pathogen-free pneumonitis. On the basis of our results, we hypothesize that the premature deaths of an/an mice are caused by a kind of chronic irradiation damage to which an/an mice are especially susceptible. 相似文献
94.
95.
Neutrophils are known to contain a major 67-kD protein that undergoes enhanced phosphorylation and translocation to the membrane during cell stimulation. Recent studies have assumed that this 67-kD phosphoprotein is the 67-kD subunit of the phagocyte oxidase (p67-phox). We compare here the protein phosphorylation patterns in lysates of normal neutrophils and neutrophils from patients with chronic granulomatous disease (CGD) that are completely deficient in p67-phox. The phosphoproteins were labeled by incubation of the cells with radioactive inorganic phosphate (32Pi) or by the addition of [gamma- 32P]ATP to electropermeabilized neutrophils. With either method, stimulation of the normal or CGD cells always resulted in an enhanced incorporation of 32p into two proteins in the 67-kD area. The extent of phosphorylation of these two proteins was very similar in the normal and CGD cells when permeabilized neutrophils loaded with [gamma - 32P]ATP were compared. Moreover, no overall differences in the protein phosphorylation patterns were observed between the normal and CGD cells. Our data indicate that the major 67-kD phosphoproteins observed in stimulated neutrophils are clearly different from p67-phox. 相似文献
96.
C Pothoulakis U Galili I Castagliuolo CP Kelly S Nikulasson PK Dudeja TA Brasitus JT LaMont 《Gastroenterology》1996,110(6):1704-1712
BACKGROUND & AIMS: Nearly all human sera contain an immunoglobulin G antibody (antigalactose) that binds the trisaccharide Gal alpha 1-3Gal beta 1-4GlcNAc expressed on cells from most mammals but not humans. Because the Clostridium difficile toxin A receptor in rodents contains this trisaccharide, the aim of this study was to examine whether antigalactose could mimic the enterotoxic effects of toxin A and bind to receptors containing this trisaccharide. METHODS: Fluid secretion, [3H]-mannitol permeability, and release of rat mast cell protease II and prostaglandin E2 were measured after luminal exposure of rat colon to either purified human anti-galactose, control immunoglobulin G, toxin A, or buffer. RESULTS: Toxin A (5 micrograms) and antigalactose (250 micrograms) but not control immunoglobulin (250 micrograms) stimulated colonic fluid secretion and caused increased mannitol permeability and rat mast cell protease II release. Antigalactose and toxin A and, to a lesser degree, control immunoglobulin G also stimulated release of prostaglandin E2, but only toxin A produced acute inflammation of rat colonic mucosa. Antigalactose and toxin A bound specifically to a single class of colonic brush border receptors with dissociation constants of 10(-6) mol/L and 5.4 x 10(-8) mol/L, respectively. CONCLUSIONS: Fluid secretion, increased permeability, and mast cell activation occur in rat colon when toxin A or human antigalactose immunoglobulin G bind to receptors bearing the trisaccharide Gal alpha 1-3Gal beta 1-4GlcNAc. (Gastroenterology 1996 Jun;110(6):1704-12) 相似文献
97.
Spectrin-alpha I/61: a new structural variant of alpha-spectrin in a double-heterozygous form of hereditary pyropoikilocytosis 总被引:3,自引:0,他引:3
Recent biochemical studies have led to the identification of abnormal spectrins in the erythrocytes of patients with hereditary pyropoikilocytosis (HPP) and hereditary elliptocytosis (HE). In this report we describe the biochemical characterization of the erythrocytes from a proband with severe HPP who is doubly heterozygous for two mutant spectrins (Sp): Sp alpha I/74 and a new, previously undetected, mutant of alpha-spectrin designated Sp alpha I/61. The proband's erythrocytes are unstable when exposed to 45 degrees C, and her membrane skeletons exhibit instability to shear stress. The content of spectrin in the proband's erythrocyte membranes is decreased to 75% of control values. The amount of spectrin dimers in crude 4 degrees C spectrin extracts is increased (58%) as compared with control values (6% +/- 4%). Limited tryptic digestion reveals a marked decrease in the normal 80,000-dalton alpha I domain, an increase in the 74,000-dalton fragment that is characteristic of Sp alpha I/74, and an increase in a series of new fragments of 61,000, 55,000, 21,000, and 16,000 daltons. Both parents are asymptomatic, but they have increased amounts of spectrin dimers (17% to 25%). Limited tryptic digestion of the father's spectrin demonstrates the presence of a previously identified abnormal spectrin (Sp alpha I/74) that is characterized by a decrease in content of the 80,000-dalton peptide and an increase in concentration of the 74,000-dalton peptide. The mother's spectrin digests show a decrease in the amount of 80,000-dalton peptide and the formation of new peptides of 61,000, 55,000, 21,000, and 16,000 daltons. The data indicate that this severe form of HPP is due to the inheritance of two distinct abnormal spectrins, Sp alpha I/74 and a new spectrin mutant, Sp alpha I/61. 相似文献
98.
CT模拟结肠镜在结肠病灶诊断中的应用 总被引:2,自引:0,他引:2
结肠癌是常见的消化道肿瘤,上海等地区的发病率有明显增高的趋势。在发达国家,结肠癌占肿瘤死亡率第二位,且与大肠腺瘤关系密切。如能早期发现有恶变先兆的息肉并切除之,可以预防结肠癌发生。目前,对结肠癌发病高危人群并未作大规模普查,部分由于患者缺乏早期主诉,或是由于现有普查手段不够有效。大便隐血试验只能发现30%~40%结肠肿瘤,乙状结肠镜不能进入近端结肠,并有10%~15%乙状结肠肿瘤漏诊。钡剂灌肠和结肠镜能检查全结肠,但有10%~15%患者行结肠镜检查失败,并且结肠镜可能使10%~20%病灶遗漏,尚… 相似文献
99.
100.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献