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1.
Fasting hypochlorhydria with gram positive gastric flora is highly prevalent in healthy old people. 下载免费PDF全文
Fifteen healthy old people mean age 84 years (range 80-91 years), were examined to assess the effect of advanced age on the microecology of the upper gastrointestinal tract. Twelve of 15 (80%) were hypochlorhydric with pH 6.6 (0.3) (mean (SEM) and a mean bacterial count of 10(8) colony forming units (CFU) per ml (range 10(5)-10(10)) in fasting gastric aspirate. Normochlorhydric subjects had low counts (< or = 10(1) CFU/ml). The microbial flora was dominated by viridans streptococci, coagulase negative staphylococci, and Haemophilus sp. Only one subject harboured significant concentrations of Gram negative bacilli with Escherichia coli (10(4-5) CFU/ml) and Klebsiella (10(4-5)). Strict anaerobes were not found. The total concentration of short chain fatty acids in gastric aspirate was 10.6 (2.9) mmol/l (mean (SEM). Absence of significant, intraluminal fermentation of xylose to CO2 was shown by the 14C-d Xylose breath test, and ambulatory manometry showed preserved fasting motility pattern of the small intestine. Serum immunoglobulins were normal. Advanced age is accompanied by fasting hypochlorhydria and colonisation with mainly Gram positive flora in the upper gut. Other factors than old age and fasting hypochlorhydria are required for colonisation with Gram negative bacilli. 相似文献
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We studied the entry of elderly uremic patients to chronic dialysis in the U.S. in 1979. We also reviewed long-term survival, causes of death, and risk factors for death in old patients on dialysis at one center for the period 1966 to 1983. A comparison of the number of patients at risk with the number entering dialysis in the United States in 1979 indicates that 80% of the patients aged 25-45 years, 30% of patients over the age of 65 years, and 6% of those over the age of 75 years entered dialysis during that period. Of 239 patients over the age of 70 years followed at the Regional Kidney Disease Program at Hennepin County Medical Center in Minneapolis, the seven-year cumulative survival was 17%. In this program withdrawal from dialysis was the commonest cause of death, accounting for 40% of all deaths. Age groups over 75 years, sex, time period, duration of dialysis, eight pre-existing degenerative diseases, living situation, family support, and site and type of dialysis were not risk factors for termination of dialysis, but living in a nursing home was. When compared to the young, total deaths and deaths from discontinuation were much higher, and this decision was made earlier. Half of the patients who died because dialysis was discontinued were competent and decided for themselves; the other half were incompetent and families and physicians made the decision.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Autoantibodies against 21-hydroxylase and side-chain cleavage enzyme in autoimmune Addison's disease are mainly immunoglobulin G1 总被引:1,自引:0,他引:1
Bøe AS Bredholt G Knappskog PM Hjelmervik TO Mellgren G Winqvist O Kämpe O Husebye ES 《European journal of endocrinology / European Federation of Endocrine Societies》2004,150(1):49-56
OBJECTIVE: Immunoglobulin G (IgG) antibodies to the steroidogenic enzymes 21-hydroxylase (21OH) and side-chain cleavage enzyme (SCC) are important diagnostic markers for autoimmune Addison's disease and autoimmune polyendocrine syndromes (APS) types I and II. The characterization of autoantibody (IgG) subclasses may reveal information on how tIssue destruction takes place; therefore, IgG subtypes of anti-21OH and anti-SCC antibodies from sera of patients with Addison's disease, APS I and APS II were determined using recombinant 21OH and SCC. METHODS: SCC(51-521) and his-SCC(51-521) were expressed by pET-scc in the Escherichia coli strain BL21 Star (DE3) and inclusion bodies were purified. Full-length, human 21OH fused to an N-terminal 6x histidine affinity tag was expressed in insect cells by using the baculovirus expression system bac-to-bac. Western blots were used to investigate the IgG subtype(s) of the autoantibodies against 21OH and SCC in patients and healthy blood donors. RESULTS: All anti-SCC positive sera (n=10) contained autoantibodies of the IgG1 subclass, while four out of ten also contained IgG3. All anti-21OH positive sera (n=16) had autoantibodies exclusively against IgG1. Sera from 20 healthy subjects did not show any reactivity against 21OH or SCC. CONCLUSIONS: The finding of a predominating IgG1 response against 21OH and SCC may suggest that T helper (Th) cells of the Th1 subclass are involved in destruction of the adrenal cortex in patients with autoimmune Addison's disease. 相似文献
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Abruzzo LV; Schmidt K; Weiss LM; Jaffe ES; Medeiros LJ; Sander CA; Raffeld M 《Blood》1993,82(1):241-246
We describe a patient with angioimmunoblastic lymphadenopathy with dysproteinemia (AILD), who subsequently developed large-cell immunoblastic lymphoma of B-cell immunophenotype. At the time of the initial diagnosis, histologic examination of an inguinal lymph node showed typical features of AILD, and there was no evidence of a monoclonal B-cell population by immunohistochemical analysis. In situ hybridization and Southern blot analysis for Epstein-Barr virus (EBV) were negative. At autopsy 2 years later, the patient had widespread lymph node and organ involvement by large-cell immunoblastic lymphoma of B-cell immunophenotype. Southern blot analysis performed on DNA extracted from lymph nodes, liver, and spleen showed two patterns of Ig heavy chain and kappa light chain gene rearrangements. The T-cell receptor beta chain gene was in the germline configuration. Analysis with an EBV terminal repeat region probe showed two clonal populations that paralleled the Ig gene rearrangement studies. Double-labeling immunohistochemistry and in situ hybridization confirmed the presence of EBV within the neoplastic B cells. The data support the hypothesis that EBV was not etiologically related to AILD in this case, and that EBV proliferation may occur after the onset of the disease. Further, the data suggest that some B-cell lymphomas that arise in the setting of AILD resemble EBV-associated B-cell lymphomas that arise in other immunodeficiency states. 相似文献
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Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model 下载免费PDF全文
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Valéria Martins Araújo CARNEIRO Ana Cristina Barreto BEZERRA Maria do Carmo Machado GUIMAR?ES Maria Imaculada MUNIZ-JUNQUEIRA 《Journal of applied oral science : revista FOB》2012,20(5):503-509
Phagocytosis by neutrophils and monocytes constitutes the main defense mechanism
against bacterial challenges in periodontitis. Phagocytosis by neutrophils has
already been evaluated, whereas phagocytic function of monocytes has hardly been
addressed so far.
Objectives
The aim of this study was to assess phagocytosis by neutrophils and monocytes in periodontitis.Material and Methods
The sample included 30 subjects with severe periodontitis and 27 control subjects without periodontal disease. The phagocytic index (PhI) was calculated as the mean number of adhered/ingested Saccharomyces cerevisiae per phagocytozing monocyte or neutrophil multiplied by the percentage of phagocytes involved in phagocytosis.Results
A significant reduction in phagocyte functions was observed in individuals with periodontitis. The median of PhI of neutrophils using non-sensitized S. cerevisiae was 3 for the control group, and 1.5 for the periodontitis group (p=0.01, Mann-Whitney test). The median of PhI of monocytes with non-sensitized S. cerevisiae was 26.13 for the control group, and 13.23 for the periodontitis group (p=0.03, Mann Whitney test). The median of PhI of monocytes assessed with sensitized S. cerevisiae was 97.92 for the control group and 60.1 for the periodontitis group (p=0.005, t-test).Conclusion
The data demonstrated a reduction in the function of phagocytes, suggesting a decrease in immune defenses in periodontitis. 相似文献10.
Camila Santos PEREIRA Marcos Vinícius Macedo de OLIVEIRA Lucas Oliveira BARROS Gabriela Alencar BANDEIRA Sérgio Henrique Sousa SANTOS John R. BASILE André Luiz Sena GUIMAR?ES Alfredo Maurício Batista DE PAULA 《Journal of applied oral science : revista FOB》2013,21(5):416-421