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31.
BACKGROUND: Treatment with omalizumab has been shown to reduce serum free IgE concentrations and to have beneficial effects on allergic airway disease. However, its effect on IgE synthesis is unknown. OBJECTIVE: To determine whether omalizumab therapy affects nasal reactivity to allergen and local IgE production. METHODS: Nineteen patients with perennial allergic rhinitis were treated with intravenous omalizumab every 2 weeks for 26 weeks in an open-label study. Serum free and total IgE concentrations were measured at baseline and every 2 weeks throughout the study. Nasal challenge to dust mite allergen was performed at baseline and after 12 and 24 weeks of treatment. Nasal lavage fluid obtained before and after each nasal challenge was evaluated for mite-specific antibodies, plaque-forming cells, and productive epsilon messenger RNA (mRNA). RESULTS: During treatment, serum free IgE concentrations were decreased by 97% to 99%, and the nasal response to allergen challenge was significantly reduced on days 80 and 164. The postchallenge increase in nasal lavage mite specific IgE was significantly reduced by treatment with omalizumab on day 168. IgE plaque-forming cells and productive epsilon mRNA were not significantly affected by omalizumab treatment. CONCLUSIONS: Omalizumab treatment markedly reduced serum free IgE and the clinical response to nasal allergen challenge. However, the absence of an effect on IgE-secreting B cells and epsilon mRNA in nasal lavage fluid suggests that omalizumab treatment for 6 months does not significantly modulate synthesis of nasal IgE.  相似文献   
32.
Zinc toxicity in the ferret   总被引:1,自引:0,他引:1  
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33.
Acquired C1 esterase inhibitor deficiency is a rare condition, usually presenting after the 2nd decade of life, and is often related to underlying conditions such as autoimmune and lymphoproliferative disorders. This case report describes a man whose initial clinical presentation with acute angioedema and whose initial estimation of a low C1 esterase inhibitor concentration indicated that he had an acquired angioedema, possibly secondary to a B cell neoplasm. A paraprotein was detected, and although its detection was serendipitous because it hinged on a spurious C1 esterase inhibitor result, this case confirms the role of C4 concentrations in the investigation of C1 esterase inhibitor deficiency. It also confirms the need to obtain repeat confirmatory samples before arriving at a diagnosis, however convincing the clinical signs may be.  相似文献   
34.
In an effort to understand the mechanisms that underpin gonadal differentiation at the time of sex determination, we identified a cDNA encoding a putative novel testis expressed scavenger receptor, Tesr. Based on its domain structure, we hypothesize that the function of Tesr is similar to that of other scavenger receptors that play roles in phagocytosis of apoptotic cells, cell-cell adhesion, and defense. Tesr mRNA was detected in fetal mouse gonads of both sexes at 11.5 days post coitum (dpc). From 12.0 dpc, Tesr expression rapidly decreased in the female and was maintained in the male. Expression was seen in embryonic mouse sites other than the testis, such as in brain, eye, head, heart, neural arch, and cartilage primordium. Tesr expression in the newborn testis was faint to undetectable, but it increased from 2 days postpartum (dpp) until 15 dpp and was found in a subset of interstitial cells and in germ and Sertoli cells. Tesr mRNA in the adult mouse testis was observed in Sertoli cells, spermatogonia, spermatocytes, round spermatids, and in a subset of interstitial cells. We conclude that Tesr is differentially expressed in the male vs. female embryonic gonad and is expressed in both the ovary and the testes postnatally after 2 dpp.  相似文献   
35.
Hormone replacement therapy can successfully treat menopausal symptoms. A postal questionnaire was used to investigate the knowledge of and attitudes to hormone replacement therapy of an age-stratified, computer-generated, representative sample of 1500 women living in the Grampian region of Scotland. A response rate of 78% was achieved. Comparisons were made between women of differing age, educational background and their current or past experience of hormone replacement therapy. The questionnaire also assessed their knowledge of osteoporosis, including the possible beneficial role of hormone replacement therapy. The results showed that women had a poor knowledge of the potential risks and benefits of oestrogen, lack of knowledge being greatest in the less educated and older women. The majority of women agreed with the view that because the menopause is brought on by diminished hormone levels, it should be viewed as a medical condition and treated as such, and also that a woman who experiences distressing menopausal symptoms should take hormone replacement therapy. Despite this, relatively few postmenopausal women were currently taking hormone replacement therapy (9%) or had taken the treatment in the past (7%), although many had experienced menopausal symptoms for over six months. The most common reason for postmenopausal women never having taken hormone replacement therapy was that they had never considered the treatment (70%) and had not discussed it with a doctor (79%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
36.
A morphologic, histochemical, and immunocytochemical study of 20 cases of pure gastrointestinal carcinoids, adenocarcinomas, and mixed neoplasms composed of both elements, so-called composite carcinoma-carcinoid tumors (CCC), was undertaken in order to correlate the morphologic patterns with the immunocytochemical localization of carcinoembryonic antigen (CEA), serotonin, and a battery of polypeptide hormones (calcitonin, glucagon, insulin, gastrin, somatostatin, and adrenocorticotropin [ACTH]). Paraffin sections from five pure carcinoids, seven pure adenocarcinomas, and eight CCC from the stomach, small bowel, appendix, and colon were studied with mucicarmine, silver impregnation stains, and a peroxidase-anti-peroxidase technic. Of the eight CCC, all were mucin positive, four were argyrophilic, and three were argentaffin positive. CEA was present in all eight, serotonin in seven, and calcitonin in one. No other neurohormonal peptides were demonstrated. The distribution of serotonin and CEA generally corresponded to the morphologic pattern, but discordance was observed in two cases, i.e., serotonin was not always localized to areas of carcinoid and CEA not always confined to areas of carcinoma. All five pure carcinoids demonstrated intracytoplasmic localization of serotonin, whereas none contained intracytoplasmic CEA. In two cases, CEA was present within acinar lumens only. The seven colonic adenocarcinomas were argyrophil and argentaffin negative. All contained CEA within the cytoplasm and in gland lumens. None contained serotonin. None of the neurohormonal peptides was localized in either pure adenocarcinomas or carcinoids. This study reveals that among gastrointestinal neoplasms displaying morphologic patterns of adenocarcinoma and carcinoid, immunocytochemical localization of CEA and serotonin confirms their bidirectional differentiation and justifies the designation "composite carcinoma-carcinoid."  相似文献   
37.
ObjectivesThe objective of this study was to assess the performance of models of primary healthcare (PHC) delivered in First Nation and adjacent communities in Manitoba, using hospitalization rates for ambulatory care sensitive conditions (ACSC) as the primary outcome.MethodsWe used generalized estimating equation logistic regression on administrative claims data for 63 First Nations communities from Manitoba (1986–2016) comprising 140,111 people, housed at the Manitoba Centre for Health Policy. We controlled for age, sex, and socio-economic status to describe the relationship between hospitalization rates for ACSC and models of PHC in First Nation communities.ResultsHospitalization rates for acute, chronic, vaccine-preventable, and mental health-related ACSCs have decreased over time in First Nation communities, yet remain significantly higher in First Nations and remote non-First Nations communities as compared with other Manitobans. When comparing different models of care, hospitalization rates were historically higher in communities served by health centres/offices, whether or not supplemented by itinerant medical services. These rates have significantly declined over the past two decades.ConclusionLocal access to a broader complement of PHC services is associated with lower rates of avoidable hospitalization in First Nation communities. The lack of these services in many First Nation communities demonstrates the failure of the current Canadian healthcare system to meet the need of First Nation peoples. Improving access to PHC in all 63 First Nation communities can be expected to result in a reduction in ACSC hospitalization rates and reduce healthcare cost.  相似文献   
38.
Recognition and management of Kawasaki disease   总被引:19,自引:0,他引:19       下载免费PDF全文
Kawasaki disease is the leading cause of acquired heart disease in children in the developed world, with coronary artery aneurysms occurring in up to 25% of untreated cases. The mean annual incidence of Kawasaki disease across Canada is about 13 per 100,000 children less than 5 years of age, based on hospital discharge data from 1990 to 1995. The cause remains unknown, and the diagnosis is based on the same clinical criteria used to describe the disease over 30 years ago. However, nonspecific clinical features, evolving presentations and atypical or incomplete presentations make early diagnosis and timely treatment difficult. Delays in diagnosis and treatment, which occur more frequently in older children, are associated with an increased risk of coronary artery aneurysms. Hence, high diagnostic suspicion and prompt referral are required to reduce the rate of cardiac complications.  相似文献   
39.
40.
New PBPK model applied to old occupational exposure to benzene   总被引:1,自引:0,他引:1  
An intensive program of benzene monitoring using new techniques was undertaken in Western Europe in the late 1960s and early 1970s. Significant exposure was found in the transport of benzene and gasoline, particularly during the loading of barges, and during the loading and operation of sea-going vessels. The ceiling threshold limit value of 25 ppm recommended at that time generated problems in assessing exposure, so alternative criteria were proposed. During that period some shore-based exposures were reported, and their significance was discussed in several articles. The information gained at that time is reexamined by physiologically based pharmacokinetic (PBPK) modeling and is used to help validate an improved PBPK model, which is described and tested on results from experimental exposure in a companion article. The old field data, comprising five specific studies, confirm the relevance of modeling to assessment of occupational exposure, and demonstrate its value for interpretation of field data, which is seldom as complete, systematic, or accurate as that obtained in experimental work. The model suggests that metabolism of benzene in humans may not be restricted to the liver. Sites and processes of metabolism merit further investigation.  相似文献   
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