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1.
The facile thiolytic cleavage of the O-2,4-dinitrophenyl (Dnp) tyrosine bond was applied to the solid-phase synthesis of the 22-amino acid residue peptide H-Asp-Ala-Val-Tyr -Thr-Gly-Leu-Asn-Thr-Arg-Asn-Gln-Glu-Thr-Tyr -Glu-Thr-Leu-Lys-His-Glu-Lys-OH, corresponding to positions 62-83 in the chain of the type 1 receptor for Fcε, domains expressed on the rat mucosal-type mast cells (line RBL-2H3). A method for the spectrophotometric determination of insoluble O-Dnp as well as of unprotected phenolic moieties of tyrosine was developed. It is based on monitoring S-Dnp-2-mercaptoethanol, produced upon O-Dnp thiolysis by 2-mercaptoethanol. © Munksgaard 1995. Dedicated to the memory of Dr. Susumu Funakoshi, a dear friend and a leader in peptide chemistry.  相似文献   
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A monthly child psychiatric clinic was established in a primary health care centre in order to offer a more accessible service to patients, and to improve liaison with primary health care professionals. Compared with the base child guidance unit, at the health centre there was a better first attendance rate, a much higher proportion of referrals from health professionals especially general practitioners, and an increased proportion of younger children referred. If further follow-up was necessary at the child guidance unit the attendance rate was very good. The service provided, although not reducing the need for a main multidisciplinary base, offered an acceptable and accessible opportunity for children with psychological problems to be assessed and treated, and for the referring professionals to have easy communication with the child psychiatrist.  相似文献   
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ABSTRACT: The conceptus is tolerated in spite of the antigenic dissimilarities between mother and fetus. A new hypothesis to account for this phenomenon is put forward. It is suggested that the vessels within the trophoblastic villi—analogous to the vessels of malignant tumors—are permeable to humoral substances but impervious to cellular elements. This property allows for the exchange of nutrients and metabolites but, at the same time, precludes the passage of leukocytes. The block to diapedesis is believed to be due to the deposition of an occlusive layer of alpha2-macroglobulin on vascular endothelium. The source of this protide is the fetal liver. In the absence of diapedesis there is no homograft reaction within the placenta. The “graft” is tolerated.  相似文献   
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Adult T-cell leukaemia/lymphoma (ATLL) was first identified in Japan in 1977 [1,2]. The causative agent, the human T-lymphotropic virus type I (HTLV-I), was isolated 3 years later by Gallo's group from a patient initially diagnosed as having mycosis fungoides but subsequently reclassified as a case of ATLL [3]. Since this time, much has been discovered about the molecular pathogenesis of the disease. Despite this, treatment of ATLL remains disappointing and the prognosis of acute and lymphoma types poor. In the United Kingdom, cases of ATLL are mainly restricted to people of Afro-Caribbean descent but the disease is of general importance because ATLL has also been reported in non-endemic areas and may possibly spread into other populations via blood transfusion as blood donors in the UK are currently not screened for HTLV-I.  相似文献   
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Genetic association of some immune-mediated human uveitic diseases with histocompatibility antigens, ethnic origin, familial background, or gender have suggested the presence of a hereditary component in susceptibility to uveitis. Uveitis is a genetically complex disease, in which genes and environment contribute to the phenotype appearance. In complex traits, genotypes of particular sets of genes, together with environmental factors, alter the probability that an individual will express the characteristic, although each individual factor is typically insufficient to cause the disease. The main susceptibility genes for clinical and experimental uveitis seem to be located within the major histocompatibility complex (MHC) region, but genes possibly regulating responses to lymphokines, hypothalamic-adrenal-pituitary axis hormones, vascular effects, and possibly T cell repertoire and other pathways play a role to determine "permissiveness" or "nonpermissiveness" to the disease.  相似文献   
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Summary. The birthweights of 664 Hindu and 132 Moslem babies were compared with those of 486 European babies born at the same hospital. The mean birthweight of the Europeans was 3362 g, compared with 3146 g for the Moslems and 2960 g for the Hindus. The Asian women were smaller than the European and tended to have a shorter length of gestation. Forty-four per cent of the Asians and 46% of the European mothers were of social classes I and II; 28% of the Europeans and 2% of the Asians smoked. There were no significant differences between Asians and Europeans in the effects of maternal size, parity, gestational age and fetal sex on birthweight. After adjustment for these variables and for cigarette smoking there was no significant difference in birthweight between the Moslems and the Europeans, but the mean birthweight of the Hindus was about 190 g lighter than that of the Europeans. Hindus from East Africa had lighter babies than those from India.  相似文献   
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Context: Health care costs in the United States are much higher than those in industrial countries with similar or better health system performance. Wasteful spending has many undesirable consequences that could be alleviated through waste reduction. This article proposes a conceptual framework to guide researchers and policymakers in evaluating waste, implementing waste‐reduction strategies, and reducing the burden of unnecessary health care spending. Methods: This article divides health care waste into administrative, operational, and clinical waste and provides an overview of each. It explains how researchers have used both high‐level and sector‐ or procedure‐specific comparisons to quantify such waste, and it discusses examples and challenges in both waste measurement and waste reduction. Findings: Waste is caused by factors such as health insurance and medical uncertainties that encourage the production of inefficient and low‐value services. Various efforts to reduce such waste have encountered challenges, such as the high costs of initial investment, unintended administrative complexities, and trade‐offs among patients', payers', and providers' interests. While categorizing waste may help identify and measure general types and sources of waste, successful reduction strategies must integrate the administrative, operational, and clinical components of care, and proceed by identifying goals, changing systemic incentives, and making specific process improvements. Conclusions: Classifying, identifying, and measuring waste elucidate its causes, clarify systemic goals, and specify potential health care reforms that—by improving the market for health insurance and health care—will generate incentives for better efficiency and thus ultimately decrease waste in the U.S. health care system.  相似文献   
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Objectives: To discover whether any consensus exists among the Association of Paediatric Anaesthetists of Great Britain and Ireland (APA) members regarding the use and acceptability (or otherwise) of physical restraint. Background: Despite growing recognition of children’s right to be consulted regarding their healthcare, the issue of how to proceed when faced with a child unwilling to undergo induction of general anesthesia remains relatively unaddressed. Methods: APA members were surveyed regarding their use or avoidance of physical restraint and alternate techniques to facilitate induction; factors affecting choice of technique; and extent of preoperative discussion. The anonymous online survey used both structured and free text responses. Results: Of 596 surveys, 310 were returned, a 52% response rate. Use of physical restraint and extent of restraint employed declines with increasing child age. Distraction techniques are frequently employed for children under 6 years, with the use of sedative premedication increasing as child age increases. Urgency of procedure, developmental delay, and preoperative discussion all have an effect. Comments demonstrated a wide range of views and lack of consensus on what constitutes physical restraint, and what degree of restraint, if any, is acceptable. Conclusion: Our results are similar to the US Society of Pediatric Anesthesia members, suggesting this remains an issue internationally. Consideration of practices in other specialties gives some guidance. Our survey shows a range of views as to what physical restraint is or involves, and what constitutes acceptable practice regarding the use or avoidance of physical restraint. We were unable to demonstrate consensus.  相似文献   
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