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951.
David A. Clark Petra C. Arck Reza Jalali Fatima S. Merali Justin Manuel Gerard Chaouat Jennifer L. Underwood James F. Mowbray 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(4):330-337
PROBLEM: Some mammalian pregnancy failure is thought to occur by immunological or immunologically modifiable mechanisms. The original model wherein spontaneous abortion was proposed to represent rejection of the conceptus as an allograft has been supplanted by a model of maternal paraimmunological natural effector cell toxicity to fetal trophoblast more closely related to tumor rejection. The problem is to integrate current information concerning the role of immunological, paraimmunological, endocrinological, and stress-triggered neural factors that determine whether or not abortion will occur. METHODS: Review of existing data. RESULTS: An integrated model is proposed. CONCLUSION: Immunological factors play an important role in abortion processes and prevention of abortions. The existence of abortogenic mechanisms and their regulation appears to be based upon optimizing survival of the species. Two new conceptual models provide a useful framework for further investigation of human pregnancy failure and its treatment. 相似文献
952.
953.
A patient with partial anomalous venous return from the left upper lobe in the presence of a large atrial septal defect is presented. The diagnosis was confirmed by selective angiographic studies. Two technical points are emphasized: first, that the exposure through a midsternal incision is excellent, and second, that the anomalous vein must be detached from its connection to the innominate or subclavian artery as high into the left chest as it is technically possible to reach. Postoperative cardiac catheterization and angiograms confirm the completeness of the repair. 相似文献
954.
Reza Rahbar DMD MD Sara O. Vargas MD Christopher R. Miyamoto MD Antonio R. Perez-Atayde MD Christopher A. French MD Caroline D. Robson MD Greg R. Licameli MD Jonathan A. Fletcher MD Karen C. Marcus MD Holcombe E. Grier MD Trevor J. McGill MD Gerald B. Healy MD 《Otolaryngology--head and neck surgery》2003,129(6):698-704
OBJECTIVE: To further evaluate the role of chromosomal translocation (15;19) in the presentation of the carcinoma (CA) of the upper aerodigestive tract. STUDY DESIGN AND SETTING: A retrospective study at a tertiary care pediatric medical center. RESULTS: Seven patients with a mean age of 12 years presented with CA of nasopharynx (N = 2), sinonasal region (N = I), parotid gland (N = 2), or larynx (N = 2). Treatments included combinations of surgery (N = 5), chemotherapy (N = 5), and radiation therapy (N = 4). One patient with sinonasal CA and one patient with laryngeal CA had chromosomal translocation (15;19); these patients both died of their disease with a mean survival of 6 months. The 5 patients without translocation (15;19) responded well to treatment and are disease-free with a mean follow-up of 47 months. CONCLUSION: The preliminary results appear to indicate poor prognosis associated with the presentation of chromosomal translocation (15;19) despite aggressive multi-modality treatment. Further investigation is needed to better understand the cause and relationship of the translocation (15;19) and aggressive behavior of these tumors. 相似文献
955.
Dr. Michael J. Belman MD Reza Shadmehr MS 《Journal of clinical monitoring and computing》1991,7(1):42-48
In a previous study, we successfully used a target feedback device, together with an external resistor, to train the ventilatory muscles of patients with chronic obstructive pulmonary disease. In this article, we describe the details of the design and function of the target feedback device. When used in conjunction with an external resistance, the target feedback device provides timing and pressure targets, together with feedback information, on whether these targets are achieved. The target feedback device consists of readily available electronic components and is relatively simple to construct. Adjustment of an external pressure knob permits setting of pressure targets. Adjustment of internal components is possible and allows control of breathing frequency, inspiratory time, and breathing waveform. 相似文献
956.
Reza Arshady 《Macromolecular chemistry and physics.》1988,189(6):1295-1303
A number of reactive styrene derivatives 3a – h was synthesized and copolymerized in suspension with styrene and divinylbenzene to produce beaded styrene-based resins 5a – h, carrying bromo, methoxy, chloromethyl, hydroxymethyl, hydroxyethyl, or α-hydroxy-4-methoxybenzyl groups. The swelling behaviour of selected samples of these resins was studied in tetrahydrofuran, toluene, dichloromethane, dioxane, ethyl acetate, dimethylformamide, and methanol. Swellability data are given for resin samples having different percentages of crosslinking and for those produced in the presence of chlorobenzene as a monomer diluent (or polymerization solvent). The significance of the swellability data are briefly discussed in terms of the nature of solvent, the degree of crosslinking and the effect of the monomer diluent on the matrix structure. Details of a series of model reactions of the resin-bound functional groups are also given, and the results are discussed on the basis of resin swellability and polymer-substrate compatibility. 相似文献
957.
Abnormalities in synovial fluid of patients with septic arthritis detected by gas-liquid chromatography. 总被引:1,自引:1,他引:0
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I Brook M J Reza K S Bricknell R Bluestone S M Finegold 《Annals of the rheumatic diseases》1980,39(2):168-172
Gas liquid chromatography was performed on synovial fluid of 94 patients with exudative arthritis. A relatively constant pattern of peaks was obtained in all synovial fluid samples. Lactic acid was increased in synovial fluid of patients with septic arthritis excluding gonococcal arthritis. In addition 2 constant peaks with retention time of 546 and 848 seconds in the chromatogram usually showed a significant increase in the synovial fluids of patients with septic arthritis (including gonococcal arthritis) but not in those from patients with sterile inflammatory or degenerative arthritis. In 1 patient with pseudomonas arthritis an increase in the peaks was noted with clinical and bacteriological relapse and subsequently there was a gradual return to normal levels during clinical improvement. Increase in synovial fluid lactic acid is useful in the diagnosis of septic arthritis. Identification of the compounds represented by the 2 peaks, which presumptively correspond to n-valeric and n-hexanoic acid, may provide further information on diagnosis, prognosis and pathogenesis of arthritis and may help in the differentiation between gonococcal and nongonococcal arthritis. 相似文献
958.
Donald B. Louria Allyn P. Kidwell Marvin A. Lavenhar Inderjit S. Thind Reza G. Najem 《Preventive medicine》1976,5(4):549-572
A review of the literature relating to a variety of diseases afflicting adults shows that only a small number is preventable by risk factor modification, and in the majority, the risk factors are the societal intoxicants alcohol and tobacco. There is also only a small number of diseases in which there is clear evidence that detection in the early presymptomatic stages results in an outcome different from that observed if the disease is detected when symptoms occur. If primary (risk factor modification) or secondary (early intervention) approaches to medicine are to be effective, health education efforts will have to be augmented markedly. An analysis of health knowledge and patterns of licit and illicit intoxicant use in four schools or school systems suggests that current health education programs are not achieving their stated objectives. A review of current screening practices for asymptomatic persons suggests that the battery of tests used might be significantly altered in order to focus efforts on those diseases that present data show reasonably convincingly can be modified by secondary prevention. A 10-point program of selective screening and risk factor modification is proposed which is believed to be achievable, practical, and acceptable to consumers. 相似文献
959.
Semnani S Sadjadi A Fahimi S Nouraie M Naeimi M Kabir J Fakheri H Saadatnia H Ghavamnasiri MR Malekzadeh R 《Cancer Detection and Prevention》2006,30(1):14-19
BACKGROUND: Previous studies have shown that upper gastrointestinal cancers are the most common cancers in Caspian Littoral, and rate of esophageal cancer (EC) in Iranian Turkmens residing in the Eastern part of littoral are among the highest in the world. Our aim was to reassess the rate 30 years later and following socioeconomic changes in the region. METHODS: A comprehensive retrospective search was undertaken to find all new cancer cases during the 1996-2000 period. Diagnosis of cancer was based on histopathological reports in 68.2%, clinical and/or radiological evidence in 29.7% and death certificate only (DCO) in 2.1% of the cases. RESULTS: A total of 5143 new cancer cases were registered of whom 3063 (59.6%) were males. The median (IQR) age was 60 (44-69) years. Age-standardized rates (ASR) for all cancers in males and females were 134.7 and 104.5 per 100,000, respectively. Based on ASR, the top five common cancers in males (excluding skin cancer) were cancers of esophagus (43.4), stomach (27.8), colorectal (10.7), bladder (7.8) and oral cavity (6.3), while in females cancer of esophagus (36.3) was followed by cancers of breast (15.7), stomach (8.3) colorectal (6.6) and cervix (3.6). CONCLUSION: We conclude that EC incidence rate has decreased to less than half the rate reported 30 years ago, while the incidence rates of colorectal and breast cancers have increased significantly. 相似文献
960.