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81.
Protocol for ultrarapid immunostaining of frozen sections   总被引:3,自引:0,他引:3       下载免费PDF全文
Rapid immunostaining of frozen sections within a tolerable time span would be very helpful for intraoperative diagnosis. A protocol was therefore established using the enhanced polymer one-step staining (EPOS) system (Dako) with antibodies against leucocyte common antigen (LCA), cytokeratin (CK), and anti-melanoma (MEL). Best results with reliable and specific immunostaining and a labelling intensity comparable to standard immunostaining protocols were achieved with fixation of samples in 100% acetone for 20 seconds (CK, LCA) or two minutes (MEL), followed by incubation of the primary antibody and development of the chromogen reaction with 3,3'diaminobenzidine (DAB) for three and five minutes at 37 degrees C, respectively. The total procedure takes only 12 minutes, thus enabling rapid immunostaining on intraoperative frozen sections. Apart from its use in tumour classification, this method is especially useful in detecting tumour cells in sentinel lymph nodes.  相似文献   
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A radioimmunoassay (RIA) which depends on the property of protein A ofStaphylococcus aureus to combine with the Fc-fragment of immunoglobulins was developed.This technique was employed to measure antibodies in human and various animal sera. It could be demonstrated that the staphylococcal RIA was at least as sensitive as the previously described radioimmunoprecipitation technique in detecting antibodies toM.pneumoniae in human sera. In addition, antibodies toM.pneumoniae could be demonstrated in sera of hamsters intranasally inoculated with the organisms. Antibodies could also be demonstrated in rabbit sera after immunization withM.pneumoniae. The test proved to be considerably more sensitive than conventional tests for detection of antibodies to the organisms. The test requires only small amounts of reagents and is relatively inexpensive.The results were presented in a preliminary form at the annual meeting of the Local Branch of the American Society for Microbiology, Frankfurt, March 1976 and the 77th ordinary meeting of the Society for General Microbiology, Glasgow, September 1976  相似文献   
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BACKGROUND: Hymenoptera venom immunotherapy in allergic patients is a well-established treatment modality for the prevention of systemic anaphylactic reactions caused by insect stings. A variety of therapy regimens exists, from conventional to rush and ultrarush modalities that operate on continuous or intermittent schedules. OBJECTIVE: The aim of this study was to report the 8-year experience with our rush venom immunotherapy regimen in predominantly high-risk patients and to compare data on safety and convenience with the results of 26 studies published from 1978 to 2001. METHODS: One hundred one patients allergic to bee, yellow jacket, or hornet venom were treated with rush Hymenoptera venom immunotherapy. Diagnosis and selection of patients for venom immunotherapy were carried out according to the recommendations of the European Academy of Allergology and Clinical Immunology. We used a 4-day regimen, and the incidence and nature of systemic reactions (SRs) were documented. Fifty-two patients were treated with honeybee venom, and 49 were treated with yellow jacket venom. RESULTS: One hundred (99%) patients reached the maintenance dose. We observed 8 injection-related SRs (0.47% of all injections given) in 7 (6.9%) patients. The number of SRs was higher in patients treated with bee venom extract (12%) compared with in patients receiving yellow jacket venom extract (2%). There was no significant difference in the risk of SRs between female and male patients. The incidence of SRs was considerably lower than the average of 17.8% reported in the literature. CONCLUSION: With a rush immunotherapy regimen over a time period of 8 years in predominantly high-risk patients, the incidence of SRs was low, despite the high number of patients with bee venom allergy, who are more likely to have side effects. Epinephrine as rescue medication was never necessary, and the regimen proved to be safe and convenient for both the patients and the medical staff.  相似文献   
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The goal of this study was to evaluate the performance of a computer-aided detection (CAD) system in full-field digital mammography (Senographe 2000D, General Electric, Buc, France) in finding out carcinomas depending on the parenchymal density. A total of 226 mediolateral oblique (MLO) and 186 craniocaudal (CC) mammographic views of histologically proven cancers were retrospectively evaluated with a digital CAD system (ImageChecker V2.3 R2 Technology, Los Altos, CA, USA). Malignant tumors were detected correctly by CAD in MLO view in 84.85% in breasts with parenchymal tissue density of the American College of Radiology (ACR) type 1, in 70.33% of the ACR type 2, in 68.12% of the ACR type 3, and in 69.70% of the ACR type 4. For the CC view, similar results were found according to the ACR types. Using the chi-square and McNemar tests, there was no statistical significance. However, a trend of better detection could be seen with decreasing ACR type. In conclusion, there seems to be a tendency for breast tissue density to affect the detection rate of breast cancer when using the CAD system.  相似文献   
86.
Recently we demonstrated an important function of keratinocyte growth factor (KGF) in wound re-epithelialization. As KGF is mitogenic for various epithelial cells, we speculated about a role of KGF in epithelial repair processes of other organs as seen in a variety of inflammatory diseases. Here we demonstrate a strikingly increased expression of KGF in surgical specimens from patients suffering from Crohn's disease and ulcerative colitis. The levels of KGF expression strongly correlated with the degree of inflammation as assessed by histological analysis of adjacent tissue and expression analysis of the pro-inflammatory cytokine interleukin-1 beta. The highest levels of KGF mRNA and protein were found in mesenchymal cells of the lamina propria, particularly in highly inflamed areas. As the KGF receptor is expressed in intestinal epithelial cells, KGF seems to act in a paracrine manner to stimulate proliferation of these cells. These data suggest a crucial role of KGF in epithelial repair after injury caused by inflammatory processes.  相似文献   
87.
Previous studies have demonstrated the existence of nuclear carbohydrate binding proteins in a variety of mammalian cells with molecular masses of 35 000, 67 000, and 70 000 (CBP35, CBP67, and CBP70), which are associated with nuclear ribonucleoprotein (RNP) complexes. CBP35 consists of two domains, an aminoterminal portion that is homologous to certain regions of proteins of the heterogeneous nuclear RNP complex, and a carboxyl-terminal portion homologous to β-galactoside-specific lectins. CBP35 it has been proposed, like the glucose-specific lectin, CBP67, to guide RNP complexes through the nuclear pore. Here we show that the exposure of mature rats to stress induces an increase in nuclear CBP35 bound to CBP67 and retained on immobilized glucose. Nuclear extracts from the livers of old rats displayed no detectable stress response. This CBP35·CBP67 association detected in rat liver is considered with respect to the CBP35·CBP70 association recently observed in HL60 cell nuclear extracts.  相似文献   
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The feasibility of the major peripheral blood leukocyte (PBL) subsets for use in qualitative and quantitative PCR to monitor secondary cytomegalovirus (CMV) infection and ganciclovir therapy was assessed with 188 blood samples derived from 40 CMV immunoglobulin G-positive renal-allograft recipients. In pp65 antigen-positive patients all leukocyte fractions, but only 79.5% of plasma preparations, were PCR positive. In pp65 antigen-negative samples from patients after antiviral treatment only 7.3% of polymorphonuclear cell (PMNL) samples, but 81.8% of peripheral blood mononuclear cells (PBMC), and 10.9% of plasma samples remained PCR positive. Similarly, in patients with latent infections only 5.0% of PMNL, but 51.7% of PBMC preparations, and 8.0% of plasma samples were PCR positive. Regarding patients with active CMV infection, CMV DNA copy numbers in PMNL correlated significantly with pp65 antigen-positive cell counts before and after onset of ganciclovir therapy. Significant differences in CMV DNA copy numbers in PMNL and plasma were observed (i) between patients with symptomatic infection and those with asymptomatic infection and (ii) between patients with active infection and those with latent infection. In contrast, PBMC harbored equally low CMV DNA levels both in patients with active infection and those with latent infections, and no decline of CMV DNA load in PBMC was observed during antiviral treatment. We conclude that detection of CMV DNA in PMNL, not in PBMC, is associated with active infections and is more sensitive than detection of CMV DNA in plasma. Negative PCR results for PMNL after antiviral therapy indicate recovery, and fewer unwanted positive results occur compared to PBMC and plasma. Therefore, purified PMNL should be preferred for analysis by qualitative CMV PCR to avoid unwanted positive results. The CMV DNA load in PBMC compared with that in PMNL is negligible during active infection, so mixed PBL are sufficient for use in quantitative PCR.  相似文献   
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