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121.
老年人的群体在不断扩大,而他们烧伤的发病率和死亡率都要比年轻人高。最近的一项病例回顾研究分析了一家烧伤中心7年来住院患者的资料,结果显示,1557位住院患者中有221位(11%)年龄在59岁以上(含59岁)。其中有97位(44%)是女性,反映出老年患者中女性比例较高。  相似文献   
122.
The factors governing in vitro basophil histamine release induced by radiocontrast material (RCM) were evaluated by the use of two RCMs (diatrizoate and metrizamide) and three structural analogs of RCM (benzoic acid, diaminobenzoic acid, and 3-acetamidobenzoic acid) in basophil histamine-release studies. Diatrizoate was chosen because it is a commonly used RCM and is routinely administered as a hypertonic drug (958 mOsm/kg or greater). Metrizamide is a newly synthesized RCM and is routinely administered in isotonic form (approximately 280 mOsm/kg). The analogs were used in hope of identifying any structure-function relationship that might exist between RCMs and the activation of a proposed basophil membrane receptor responsible for the induction of de granulation. In addition, results in a control group of normal subjects were compared with those in a group of patients who had experienced anaphylactoid reactions to intravenous RCM. Basophils from both groups were incubated with diatrizoate and metrizamide to assess their relative sensitivity to these drugs. Both metrizamide and diatrizoate induced in vitro histamine release. Therefore hypertonicity is not an absolute requirement for RCM-induced in vitro basophil de granulation. Although there was a trend far reagents without a prosthetic group at position 5 on the benzene ring (especially 3-acetamidobenzoic acid) to induce more release of histamine than reagents with such a prosthetic group, differences between these reagents did not reach statistical significance. Therefore no clearcut structure-function relationship could be demonstrated. “Reactor” subjects released significantly-larger percents of their intracellular histamine than did “nonreactors” (p < 0.05). Degranulated cells retained their ability to exclude trypan blue, an observation suggesting that RCM-induced histamine release does not involve cell death.  相似文献   
123.
Monoclonal antibody L26 is a highly selective marker of B cells and B-cell neoplasms in paraffin-embedded tissues, but it suffers from the drawback that the target molecule has not been identified. In this paper we provide evidence by two independent techniques that antibody L26 recognizes an intracellular epitope on the CD20 antigen (a pan B-cell marker). When this antigen was redistributed on the surface of unfixed viable B cells by incubation with monoclonal anti-CD20 followed by anti-mouse Ig, the diffuse cytoplasmic staining of L26 was abolished and replaced by coincident dotlike labeling for antibody L26 and the CD20 antigen. None of the other antibodies tested (covering 10 different B-cell-associated antigens) had this effect on the L26 staining pattern. Furthermore, COS-1 cells transfected with cDNA encoding the CD20 molecule gave positive staining with antibody L26 and with two other CD20 reagents, but not with antibodies to other pan B-cell markers (eg, CD19 and CD22).  相似文献   
124.
Assessment of the growth fraction of non-Hodgkin's lymphomas may provide useful additional prognostic information to that obtained with conventional histological criteria. The monoclonal antibody Ki-67 has been reported to provide such information immunocytochemically in tissue biopsy specimens from lymphoma as well as other tumours. This study was undertaken to assess whether this approach could be extended to fine needle aspiration (FNA) biopsy specimens which are becoming increasingly important in the diagnosis of lymphoma. In 21 cases of non-Hodgkin's lymphoma the rate of tumour proliferation estimated by Ki-67 immunostaining of FNA material, obtained from surgically removed specimens, was compared with that obtained on tissue biopsy. The correlation between both preparations was excellent, indicating that FNA biopsy material is suitable for the immunocytochemical assessment of the growth fraction of non-Hodgkin's lymphoma.  相似文献   
125.
We found that 41 of 75 (55%) children with Haemophilus influenzae type b disease (70 cases of meningitis, 2 of cellulitis, 2 of septic arthritis, and 1 of epiglottitis) and 2 of 120 (1.7%) children with upper respiratory infection were colonized with H. influenzae type b in the nasopharynx (NP). Of these 43 NP strains from children with systemic H. influenzae type b disease, 7 (16%) adhered to human buccal epithelial cells. The strains isolated from the systemic site of all children, including children from whose NP adherent bacteria were isolated, did not adhere to buccal epithelial cells in vitro. Each adherent NP strain had biotype (I), serotype (b), and antibiotic susceptibility (sensitive) similar to that of the corresponding nonadherent systemic isolate. With one exception, all NP-systemic pairs had similar major outer membrane proteins. Six of the seven NP strains had a protein band in the whole cell lysate preparation with a molecular weight between 22,000 and 23,000, which could not be seen in the nonadherent cerebrospinal fluid strains. Electron micrographs of all adherent strains showed that more than 95% of the organisms examined were highly piliated, whereas the nonadherent strains were not piliated. All piliated strains agglutinated human erythrocytes. Adherence to buccal epithelial cells and agglutination of erythrocytes could not be blocked by mannose or alpha-methyl-D-mannoside. We speculate that piliation is not important for NP colonization by H. influenzae type b and that the loss of pili may be required for host invasion.  相似文献   
126.
The 7th International Workshop on Human Leucocyte Differentiation Antigens (HLDA7) studied a number of newly characterised molecules relevant to human leucocyte differentiation and function. The HLDA organisation, which devised and continues to maintain the CD nomenclature, is responsible, under the auspices of IUIS and WHO, for the nomenclature of all leucocyte differentiation markers. The 7th Workshop redefined a number of (principally carbohydrate) molecules, and assigned CD names to approximately 80 new molecules. This update lists, in tabular form, the redefined and newly assigned names, together with antibodies, which have been confirmed under Workshop conditions as specific for the new and redefined molecules. The major features of the cellular expression patterns are summarised, and a LocusLink accession number provided to enable the reader to access more detailed information through http://www.ncbi.nlm.nih.gov/LocusLink.  相似文献   
127.
Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.  相似文献   
128.
129.
Experimental transmission of duck hepatitis B virus   总被引:22,自引:0,他引:22  
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130.
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