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61.
In the oral cavity, the immune system is constantly exposed to unique tissue‐specific signals, including a rich community of commensal microbes and their metabolites, continuous tissue damage from mastication, and antigens from food and airborne particles. How this unique combination of signals participates in the training of specialized immunity at this site is not well understood, yet imbalance of local responses is linked to tissue‐specific disease susceptibilities with the prototypic disease being periodontitis. However, the oral mucosa is also well recognized as a site where systemic inflammatory and autoimmune diseases often manifest, indicating that systemic immune deregulation is reflected in the function of the oral immune system. This commentary will discuss both aspects of compartmentalized and systemic immunity at the oral mucosa. 相似文献
62.
Simsek S; Faber NM; Bleeker PM; Vlekke AB; Huiskes E; Goldschmeding R; von dem Borne AE 《Blood》1993,81(3):835-840
Platelets from 200 random Dutch blood donors were typed for the human platelet alloantigens HPA-1 to -5 recognized at present and for Naka. Naka is an epitope on glycoprotein IV, not expressed on the platelet of individuals with hereditary GP IV deficiency. Platelet immunofluorescence and monoclonal antibody-specific immobilization of platelet antigens (MAIPA) were applied for this purpose. The observed phenotype frequencies were 97.86% and 28.64% for HPA-1a and -1b, 100% and 13.15% for HPA-2a and -2b, 80.95% and 69.84% for HPA-3a and -3b, 100% and 0% for HPA-4a and -4b, 100% and 19.7% for HPA-5a and HPA-5b, respectively. Platelets from all donors reacted with the anti-Naka antibodies. To determine the gene frequencies for the HPA-1, HPA-2 and HPA-3 systems directly, DNA from 98 of these donors was isolated from peripheral blood mononuclear leucocytes and specific fragments were amplified by polymerase chain reaction (PCR). The fragments were analyzed using allele-specific restriction enzymes (ASRA). In all amplified PCR products an "internal control" for each assay, ie, a restriction site for the applied enzyme independent from the phenotype of the donor was present. In all donors tested, phenotypes, as determined by serological methods and genotypes, directly determined by the ASRA, were identical. Thus, the PCR-ASRA described in this report is a practical and reliable technique for the determination of alleles that code for platelet antigen allotypes, at least in the Dutch population. 相似文献
63.
Targeted disruption of the murine tissue factor gene results in embryonic lethality 总被引:21,自引:9,他引:21
Tissue factor (TF) is an integral membrane glycoprotein that is believed to be the physiologic initiator of the blood coagulation cascade. Disruption of the mouse tissue factor gene leads to embryonic lethality between days E9.5-E11.5 of gestation. On E9.5, TF(-/-) embryos appear indistinguishable from their TF(+/+) and TF(+/-) littermates. By E10.5, TF(-/-) embryos are severely growth retarded, appear nearly bloodless, and are in most cases dead. Initial observations suggest that TF(-/-) embryos are dying of circulatory failure. Approximately 15% of the TF(-/-) embryos survive beyond E10.5, but none complete gestation. Heterozygotes appear normal and free of bleeding complications. 相似文献
64.
RS McLeod BG Wolff AH Steinhart PW Carryer K O'Rourke DF Andrews JE Blair JR Cangemi Z Cohen JB Cullen RG Chaytor GR Greenberg NM Jaffer KN Jeejeebhoy RL MacCarty RL Ready LH Weiland 《Gastroenterology》1997,113(6):1823-1827
BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7) 相似文献
65.
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67.
Albert NM, Gillinov AM, Lytle BW, Feng J, Cwynar R, Blackstone EH. A randomized trial of massage therapy after heart surgery. Heart Lung 2009; 38: 480–90. 相似文献
68.
69.
Computer simulation in conjunction with medical thermography as an adjunct tool for early detection of breast cancer 总被引:1,自引:0,他引:1
Background
Mathematical modelling and analysis is now accepted in the engineering design on par with experimental approaches. Computer simulations enable one to perform several 'what-if' analyses cost effectively. High speed computers and low cost of memory has helped in simulating large-scale models in a relatively shorter time frame. The possibility of extending numerical modelling in the area of breast cancer detection in conjunction with medical thermography is considered in this work.Methods
Thermography enables one to see the temperature pattern and look for abnormality. In a thermogram there is no radiation risk as it only captures the infrared radiation from the skin and is totally painless. But, a thermogram is only a test of physiology, whereas a mammogram is a test of anatomy. It is hoped that a thermogram along with numerical modelling will serve as an adjunct tool. Presently mammogram is the 'gold-standard' in breast cancer detection. But the interpretation of a mammogram is largely dependent on the radiologist. Therefore, a thermogram that looks into the physiological changes in combination with numerical simulation performing 'what-if' analysis could act as an adjunct tool to mammography.Results
The proposed framework suggested that it could reduce the occurrence of false-negative/positive cases.Conclusion
A numerical bioheat model of a female breast is developed and simulated. The results are compared with experimental results. The possibility of this method as an early detection tool is discussed.70.
K. M. Kilbride F. L. Paveglio A. L. AltstattRID=""ID="" <E>Present address:</E> Chiswell Lane Silver Spring MD USA W. G. Henry C. A. JanikRID=""ID="" <E>Present address:</E> Palo Verde Albuquerque NM USA 《Archives of environmental contamination and toxicology》1998,35(2):236-248
Throughout the western United States, studies have identified various detrimental effects of contaminants to aquatic biota
from the use of agricultural drainage water for management of arid wetlands. However, little is known about the relative contributions
of contaminant loading from pollutants dissolved in water compared with those carried by drifting material (e.g., detritus) associated with drainage water. Consequently, we determined loading rates for contaminants dissolved in water and
those incorporated by drifting material for drainage (Diagonal Drain) as well as fresh (S-Line Canal) water used for wetland
management at Stillwater National Wildlife Refuge (SNWR), Nevada during the early, middle, and late periods of the irrigation
season (June through mid-November) in 1993. We found loading rates for trace elements throughout the irrigation season were
almost entirely (> 98%) associated with contaminants dissolved in the water rather than incorporated by drift. Although drift
contributed little to the total loading for trace elements to SNWR wetlands, contaminant concentrations were much greater
in drift compared with those dissolved in water. Loading rates for dissolved As, B, Hg, and total dissolved solids (TDS) differed
among periods for the Diagonal Drain. Along the Diagonal Drain, loading rates for dissolved As, B, Hg, Mo, unionized ammonia
(NH3-N), TDS, and Zn differed among its three sampling sites. B was the only trace element with differences in loading rates for
drift among periods from the Diagonal Drain. In contrast, loading rates for As, B, Cr, Cu, Hg, Se, and Zn in drift differed
among periods for the S-Line Canal. Along Diagonal Drain, loading rates in drift for B (middle and late periods), Cr, Cu,
and Zn differed among sites. Hg (xˉ ≥ 12.0 ng/L) and NH3-N (xˉ ≥ 0.985 mg/L) dissolved in water as well as B (xˉ ≥ 97.4 μg/g DW) and Hg (xˉ ≥ 0.461 μg/g DW) in drift from the Diagonal
Drain and S-Line Canal exceeded screening levels (SLs) for protection of aquatic biota throughout the irrigation season. Dissolved
As (xˉ ≥ 0.0426 mg/L) in water from the Diagonal Drain during all periods exceeded the SL for protection of aquatic biota.
Dissolved B (xˉ = 1.03 mg/L) in water from the Diagonal Drain during the early period exceeded the SL for protection of aquatic
biota.
Received: 18 September 1997/Accepted: 5 February 1998 相似文献