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141.
Histopathology of gastric carcinoids: a survey of 42 cases 总被引:6,自引:0,他引:6
An unselected series of 42 gastric carcinoids has been reviewed. Clinically the tumours simulated common gastric lesions including ulcer, polyp and carcinoma. No endocrine symptoms were identified. The tumours were most frequent in the body of the stomach and in 25% in that site were multiple. Morphologically most tumours when classified according to Soga (1974) demonstrated a mixed growth pattern. Six tumours displayed an atypical morphology (type D): they were larger and metastasized more frequently than the rest of the tumours. Six tumours contained a few scattered argentaffinic cells but the others were negative indicating negligible serotonin secretion in only a few cases. The Grimelius argyrophilic reaction was positive in most cells in all tested tumours except in three, two of which showed atypical morphology (type D). It is suggested that gastric carcinoids with a type D morphology or a minority cell population of argyrophil cells are dedifferentiated carcinoids which are biologically nearer to gastric carcinomas. The most frequent clinicopathological correlation was achlorhydria linking pernicious anaemia and gastric carcinoids. This indicates pathogenetic similarities between gastric carcinoids and gastric carcinomas. 相似文献
142.
用PCR技术产前诊断人巨细胞病毒感染 总被引:3,自引:0,他引:3
用ELISA法筛选早孕妇女血人巨细胞病毒IgM(HCMV-IgM),在孕12 ̄20周用聚合酶链式反应(PCR)技术检测其羊水中HCMV-DNA,对胎儿巨细胞病毒感染作出产前诊断。在384例孕妇中,筛选出血HCMV-IgM阳性26例为实验组,其羊水HCMV-DNA检出率为34.62%;从258例HCMV-IgM阴性中选出20例为对照组,其羊水HCMV-DNA检出率为10.0%,两组比较有显著性差异( 相似文献
143.
Klaus Hamprecht Matthias Vochem Andrea Baumeister Michael Boniek Christian P Speer Gerhard Jahn 《Journal of virological methods》1998,70(2):167-176
Human cytomegalovirus (HCMV) DNA can be detected in different compartments of human milk. A protocol for the preparation of milk whey free of fat and cells for the detection of human cytomegalovirus (HCMV) by nested PCR is presented. This is based upon the experience of the separation of more than 200 milk specimens of healthy seropositive breast feeding mothers. HCMV DNA could be detected in freshly centrifuged and filtrated milk whey specimens without contamination by cellular DNA. In limiting dilution experiments using HCMV plasmid DNA, the effect of different DNA extraction procedures from native milk and milk whey on the detection limit of cytomegaloviral DNA was demonstrated. About 200 viral genome equivalents/ml in milk whey or native milk were detectable by classical organic phenol/chloroform extraction or a spin column method, respectively. The detection of viral DNA in milk cells depended on a minimum number of milk cells (105–2×105) available for DNA extraction. In contrast to the findings of cytomegaloviral DNA in native sera or plasma of immunosuppressed patients we failed to amplify low level viral DNA from native breast milk by nested PCR due to an inhibition of Taq polymerase by lipid components. Finally, the course of cell associated and cell free DNAlactia was monitored. Analyzing sequential milk specimens, in some cases the presence of HCMV DNA in colostrum could be demonstrated. DNAlactia of milk cells and whey was partially discordant. Onset (week 1–4 after delivery) and duration (2 weeks up to more than 3 months) of DNAlactia showed distinct individual patterns. The methods described, allow further analysis of the mechanisms involved in the postnatal HCMV transmission by breast feeding seropositive mothers. 相似文献
144.
Marie-Paule Roth Laurence Dolbois Nicolas Borot Claire Amadou Michel Clanet Pierre Pontarotti Hlne Coppin 《Human immunology》1995,43(4):276-282
The MOG locus, located on chromosomal bands 6p21.3-p22 and mapped about 100 kb telomeric to HLA-F, was isolated from cosmid ICRFcl09A2434 and shown to contain three microsatellites. These CA-repeat polymorphic markers were characterized in a sample of 173 healthy unrelated individuals and 84 DNAs from the HLA Workshop reference panel, by a method combining fluorescence labeling of PCR products and use of an automated DNA sequencer. For the three markers, frequencies of heterozygotes are well predicted from allele frequencies by the Hardy—Weinberg rule, which suggests that problems of allele nonamplification are unlikely. Typing of cell lines homozygous in the HLA region allowed unambiguous definition of 81 HLA-MOG haplotypes and showed that several HLA ancestral haplotypes extended to the MOG region. The high degree of polymorphism (59%, 51%, and 81% at the three loci, respectively, and 87% at the haplotype level) makes these new markers informative for association or linkage studies with diseases such as hemochromatosis or multiple sclerosis, and for studies aimed at precisely delineating the site of crossover in chromosomes in which recombination occurred in the distal part of the HLA class I region. 相似文献
145.
E. Obál Jr. G. Benedek A. Jancsó-Gábor F. Obál 《Pflügers Archiv : European journal of physiology》1979,382(3):249-254
Salivary thermolytic mechanism (weight of salivary glands, effect of desalivation on water intake and body temperature, grooming activity) as well as escape behaviour and reaction to heat pain were studied in capsaicin-desensitized and control rats exposed to various warm ambient temperatures. Body temperature of the desensitized rats increased more than the controls at all the ambient temperatures studied (32, 34 and 36°C); however, significant differences in the mechanism of salivary cooling were obtained only at 34 and 36°C. Central impairment of saliva spreading in desensitized rats seems evident. Complete surgical desalivation did not increase hyperthermia of control and desensitized animals in warm environments. Therefore other mechanisms, primarily vasodilatatory, must also be involved in the rat's thermolytic normal response. Although desensitized rats did not show a tendency to escape from the warm environment their response to heat pain was normal. In conclusion, it is suggested that heat perception in desensitized animals is impaired; however, the existence of some capsaicin-insensitive thermolytic mechanisms (prone extension of the body) cannot be excluded.Supported by the Scientific Research Council, Ministry of Health, Hungary /4-05-0303-04-2/0/ and MTA-OM-MÉM-EÜM 70.211/79 相似文献
146.
The one-way mixed lymphocyte reaction (MLR) is a useful model of the graft-vs.-host (GvH) response that occurs following bone-marrow transplantation (BMT). Previous studies of the MLR have shown high levels of type-1 cytokine production, such as IL-1, IL-6, IFN-γ and TNF-, but low or undetectable levels of type-2 cytokines, such as IL-4 and IL-10. Here, through establishing optimal conditions for the examination of levels and kinetics of a more definitive panel of type-1/type-2 cytokines (IL-4, IL-5, IL-10 and IL-13, IFN-γ, TNF- and the soluble IL-4 receptor) we show that, contrary to previously published data, the human alloresponse is truly heterogeneous, resulting in abundant type-2 as well as type-1 cytokine secretion. The kinetics of cytokine levels in the MLR show surprising complexity, suggesting a well-defined regulation as the alloresponse develops over time. Furthermore, each MLR responder:stimulator combination tested produces a composite cytokine profile that is intrinsic to that particular pairing. These combination-specific cytokine responses are reproducible when tested on multiple occasions over time. These data reveal a potential clinical application for the cytokine MLR in selecting donors for BMT with the least inflammatory cytokine profile. Additional analysis of this system reveals that the bulk of cytokine measured is both allospecific and T-cell-derived, with comparatively low levels produced through an autologous mechanism. Interestingly, although most of the cytokine detected is produced by CD45RO+ ‘mature/activated’ T cells, CD45RA+ ‘naive’ T cells are responsible for transient early production of IL-4. This novel finding suggests that naive T cells themselves could regulate type-1/type-2 developmental fate through an autocrine IL-4 mechanism. 相似文献
147.
Anti-T-cell strategies in the treatment of allergic disease 总被引:1,自引:1,他引:1
Specific allergen immunotherapy (SIT) has been shown to be effective in modulating allergic responses in diseases such as rhinitis and asthma. However, the ability of whole allergen to cross link mast cell bound IgE, resulting in release of mediators such as histamine, has limited the application of this therapy to carefully selected patients who have failed conventional pharmacotherapy. The use of peptide sequences corresponding to T cell epitopes of the allergen has been postulated as an alternative to SIT in which high molar doses of T cell epitope can be delivered over a shorter time period and with improved safety. Using peptides from the sequence of the major cat allergen, Fel d 1, we have demonstrated the ability to induce transient T cell activation, resulting in isolated late asthmatic reactions, which are followed by prolonged periods of allergen-specific hyporesponsiveness, both to peptide re-challenge and to cutaneous challenge with whole allergen. Thus, peptide therapy may prove safe and efficacious in the treatment of allergic diseases. 相似文献
148.
Narayan P. Verma Cynthia D. Nichols Manfred F. Greiffenstein Rajinder P. Singh Deborah Hurst-Gordon 《Brain topography》1989,1(3):183-191
Summary Thirty subjects (normal controls, patients with putative subcortical dementia and non-demented patient controls) were studied using advanced neurophysiological (16 scalp-electrode positions, computer-assisted brain electrical activity mapping, auditory oddball paradigm) and neuropsychological techniques. Our study suggests that waves earlier than P3 (N1, P2 and N2) are all correlated with global measures of cognitive functions. They are, however, differentially correlated with specific measures of cognitive functions, N1 and P2 with mental speed and N2 with short-term memory. The abnormalities of these waves (earlier than P3) may be an electrophysiologic marker of dementia in patients with putative subcortical states. 相似文献
149.
The importance of thromboxane A2 (TXA2 ), one of the arachidonate metabolites, in the pathogenesis of bronchial asthma has been emphasized recently. Because aerosolized administration of antiasthmatic drugs is effective and safe, this study examined the effect of aerosolized TXA-2 receptor antagonist (S-1542) on allergic bronchoconstriction in passively sensitized and mechanically ventilated guinea pigs. Under the cover of antihistamine, antigen-induced bronchoconstriction was markedly inhibited by pretreatment with aerosolized S-1452 inhalation in a dose-dependent manner. Although aerosolized S-1452 itself provoked weak bronchoconstriction for its partial agonist effect, bronchial responsiveness to inhaled histamine did not change 10 min after S-1452 inhalation. These results indicate that aerosolized S-1452 may be useful in treating bronchial asthma. 相似文献
150.
原位PCR技术检测石蜡包埋脑组织中人巨细胞病毒DNA 总被引:6,自引:0,他引:6
应用原位聚合酶链反应(ISPCR)技术检测了25例尸检畸形胎儿石蜡包埋脑组织中人巨细胞病毒(HCMV)DNA,并与普通PCR及原位杂交(ISH)进行了比较。ISPCR、PCR及ISH检测阳性率分别为44%,36%及20%。与ISH相比较,ISPCR不仅检出阳性率高,而且信号强度增强。研究结果提示,IS-PCR是诊断HCMV感染的快速、敏感、特异的实用方法。 相似文献