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691.
The effect of anti-IL-10 on proliferation and cytokine production in human schistosomiasis: fresh versus cryopreserved cells 总被引:1,自引:0,他引:1
JANE L. GROGAN PETER G. KREMSNER RE M. DEELDER & MARIA YAZDANBAKHSH 《Parasite immunology》1998,20(7):345-349
In this study we neutralized endogenous IL-10 in PBMC from individuals chronically infected with Schistosoma haematobium by using anti-IL-10 MoAbs, and examined the effect and adult worm antigen (AWA)-specific responses in both fresh or cryopreserved cells. Anti-IL-10 alone increased background proliferation of PBMC, but did not augment the AWA-specific responses in either fresh or frozen cells. In freshly isolated PBMC, IFN-γ production in response to AWA was enhanced significantly in the presence of anti-IL-10. In cryopreserved cells, the augmentation of IFN-γ in the presence of anti-IL-10 was four-fold less than in the freshly-isolated cells. Neutralization of IL-10 had no effect on IL-4 production. These data show that IL-10 plays a role in specifically down-regulating Th1- but not Th2-type responses and, in contrast to previous reports, anti-IL-10 does not augment proliferation to parasite antigen in chronic schistosomiasis . 相似文献
692.
Neck neoplasms: MR imaging. Part II. Posttreatment evaluation 总被引:1,自引:0,他引:1
Glazer HS; Niemeyer JH; Balfe DM; Hayden RE; Emami B; Devineni VR; Levitt RG; Aronberg DJ; Ward MP; Lee JK 《Radiology》1986,160(2):349-354
Thirty-three patients who had undergone prior surgery and/or radiation therapy for malignant neoplasms of the neck were studied with magnetic resonance (MR) imaging. Twenty-seven of these patients were also evaluated with computed tomography (CT). Ten patients were healthy posttreatment volunteers, and 23 had documented tumor recurrence. MR images better demonstrated normal muscular landmarks, especially in patients with obliterated fat planes. Areas of posttreatment fibrosis or scarring were low in signal intensity with all MR pulse sequences. However, in three patients, high signal intensity from postradiation edema of the supraglottic area mimicked neoplasm. In patients with recurrent tumor, MR imaging was superior to CT in defining the relationship of tumor and muscle and in demonstrating vascular anatomy when no intravenous contrast material was given during the CT examination. In two patients tumor and fibrosis were separated on MR images because of signal intensity differences. CT scans, however, showed adjacent bone and cartilage anatomy better. Our data indicate that an MR examination may be helpful in patients in whom CT is indeterminate either because of anatomical distortion or suboptimal demonstration of vascular anatomy. 相似文献
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695.
Improvement in mammography quality control: 1987-1995 总被引:1,自引:0,他引:1
Hendrick RE; Chrvala CA; Plott CM; Cutter GR; Jessop NW; Wilcox-Buchalla P 《Radiology》1998,207(3):663
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Amino acid esters are racemized by dissolution in a mixture of aliphatic ketones and carboxylic acids. The racemization rate mainly depends on the structure of the amino acid and on the kind of ketone and carboxylic acid used, the best racemizing medium being acetone containing 15% acetic acid. The mechanism of the racemization and the practical consequences of this study in the optical resolution field are discussed. 相似文献
699.
Glazer HS; Niemeyer JH; Balfe DM; Devineni VR; Emami B; Hayden RE; Aronberg DJ; Levitt RG; Ward MP; Sagel SS 《Radiology》1986,160(2):343-348
Untreated neoplasms of the neck (tumors of the oropharynx, supraglottic area, carotid body, and thyroid, in addition to malignant lymphadenopathy) were evaluated in 23 patients with magnetic resonance (MR) imaging. The results were compared with computed tomographic (CT) scans in 20 patients. Contrast between tumor and fat was best on relatively T1-weighted images (500/30-35 [TR msec/TE msec]), whereas separation of tumor and muscle was best with relatively T2-weighted pulse sequences (1,500/90). Balanced images (1,500/30-35) provided best overall image quality and best demonstrated vascular anatomy. MR imaging was usually superior to CT in showing the relationship of tumor mass to muscle. MR imaging and contrast material-enhanced CT were equivalent in most patients in defining vascular anatomy, but MR imaging was superior when intravenous contrast material was not administered. However, CT was more helpful in showing bone and cartilage anatomy, and in some patients CT also was better in showing airway abnormalities. Despite these limitations, MR imaging is a promising imaging technique for studying neoplasms of the neck. 相似文献
700.
Cox DJ Ritterband LM Quillian W Kovatchev B Morris J Sutphen J Borowitz S 《Journal of pediatric psychology》2003,28(6):375-382
OBJECTIVE: To develop and test a scale for parent and child, evaluating theoretical and clinical parameters relevant to children with encopresis. Encopretic children were hypothesized to have more bowel-specific, but not more generic, psychological problems, as compared with nonsymptomatic control children. In addition, mothers were also believed to be more discerning than children. METHODS: The Virginia Encopresis-Constipation Apperception Test (VECAT) consists of 9 pairs of bowel-specific and 9 parallel generic drawings. Respondents selected the picture in each pair that best described them/their child. It was administered to encopretic children (N = 87), nonsymptomatic siblings (N = 27), and nonsymptomatic nonsiblings (N = 35). The mothers of all the participants also completed the VECAT. Encopretic children were retested 6 and 12 months posttreatment with Enhanced Toilet Training. RESULTS: The VECAT demonstrated good test-retest reliability and internal consistency. Encopretic children and their mothers reported more bowel-specific, but not more generic, problems. Bowel-specific scores improved significantly posttreatment only for those patients who demonstrated significant symptom improvement. Mothers were significantly more discerning than children. CONCLUSION: The VECAT is a reliable, valid, discriminating, and sensitive test. Bowel-specific problems appear to best differentiate children with and without encopresis. 相似文献