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101.
降钙素原的临床诊断价值   总被引:1,自引:0,他引:1  
降钙素原是有激素活性降钙素的前体物质。在正常人体中降钙素原的血清浓度极低未能检测出,而在严重全身细菌性感染其血清浓度可见明显增高,并且已证实降钙素原是脓毒血症时最早出现的炎症标记物之一。本文就降钙素原的结构,来源,生物学功能及临床应用作一综述。  相似文献   
102.
ROC analysis of alcoholism markers – 100% specificity   总被引:1,自引:0,他引:1  
A combination of 4 so-called markers of alcoholism, i. e. methanol, aceton + 2-propanol, γ-glutamyl-transferase and carbohydrate deficient transferrin, was investigated in 341 blood samples from alcoholics and non-alcoholics. From the history of alcohol consumption, four defined subgroups were formed: non-alcoholics divided into (A) 33 persons with no ethanol consumption during the past year and (B) 60 persons with daily consumption less then 40 g ethanol. Alcoholics were divided into (C) 177 persons with no ethanol at the time of admission/first blood sampling (withdrawal therapy) and (D) 71 persons with positive ethanol levels on admission/first blood sampling. All markers showed different extents of overlap between the collectives of alcoholics and non-alcoholics. By logistic regression, a formula was developed combining these markers with different mathematical weights. Thus an “Alc-Index” could be calculated for each individual. The ROC curve connecting all individual values gives an ideal form with 100% specificity and nearly 93% sensitivity. The threshold between the collectives of alcoholics and non-alcoholics was defined by the Alc-Index value 1.7. This was associated with no false positives among the non-alcoholics while nearly 93% of the alcoholics exceeded this index. The ROC-based calculation of the Alc-Index thus seems to be the most effective method for the diagnosis of alcoholism. Received: 24 June 1999 / Received in revised form: 1 November 1999  相似文献   
103.
电磁辐射对生物体的生物学效应   总被引:5,自引:0,他引:5  
近年来,在职业场所或在家中,电磁辐射的存在越来越广泛.电磁辐射可对生物体具有致伤效应,目前已成为医学领域的重大研究课题.该文就细胞毒性、基因毒性、外遗传毒性这三条基本途径,对电磁辐射引起生物学效应的可能机制作一概要综述.  相似文献   
104.
An integral part of routine health checkups involves laboratory measurements on various analytes in the blood. It is then common to compare the value of two consecutive measurements sampled at different times from the same patient. A “significant” change requires an action (additional sample and/or clinical action). The current rule is to check whether the relative range of measurement is larger than a certain critical threshold. This rule should guarantee a specified confidence level (e.g., 95%), but its derivation was based on an approximation. We derive the exact distribution and show that it is related to the doubly noncentral F distribution. The currently used threshold values are compared with the exact ones, and some limited power calculations are presented to detect changes in the patient condition.  相似文献   
105.
The decades-long contamination of Gruinard Island by anthrax is now a well-known part of the history of biological weapons (BW) development, as well as that of military encroachments in the Scottish Highlands and Islands (and the authorities' rather less persistent efforts at damage limitation). Some accounts have included the related episode, reportedly well-remembered by local people, of anthrax contamination on the mainland close to Gruinard. This occurred in 1942-43, when BW experiments were conducted on the island as part of the war effort by scientists from Porton Down under the auspices of the British government. After much top-level discussion, payments were made to the owners of animals that had died as a result of the contamination. The episode had a bearing on discussions about the future of the island and on subsequent policy with regard to the siting, conduct and secrecy of BW experiments.  相似文献   
106.
Chemical, biological, radiological and nuclear (CBRN) hazards may be encountered during any major incident. General considerations include modifications to triage, managing contaminated or contagious casualties, and the identification and appropriate management of intoxicated/infected/irradiated/injured casualties. In dealing with chemical incidents, characteristics such as toxicity, latency and persistency need to be understood in order to manage casualties appropriately in terms of triage category, life-saving interventions and assessment of contamination risk to responders. Biological agents can be differentiated into live agents (bacteria, viruses and fungi) and toxins. Live agent characteristics and management depend on pathogenicity, virulence, lethality, infectivity and transmissibility, whereas toxins are treated similarly to chemical agents. Radiological and nuclear hazards are managed similarly and may cause irradiation, contamination (external and internal) or a combination with or without trauma. A generic and structured approach is advised to deal with all major incidents including those with a suspected of confirmed CBRN hazard. All healthcare professionals that may be involved in the response to such an incident need to be familiar with the principles of CBRN incident management and of CBRN casualty management as described in this article.  相似文献   
107.
108.

Science and Conscience

In the Shadow of the Bomb: Oppenheimer, Bethe, and the Moral Responsibility of the Scientist By Silvan S. Schweber Princeton University Press, Princeton NJ, 2000, 260 pp., £15.95, ISBN 0–691–04989–0.

Sanctions

Iraq Under Siege: The Deadly Impact of Sanctions and War Edited by Anthony Amove Pluto, London, 2000, 224 pp., £10.99 pbk. ISBN 0–7453–16S9‐X, £35.00 hbk, ISBN 0–7453–1660–3.

Nurses at War

Nurses at War: Women on the Frontline 1939–45 By Penny Starns Sutton, Stroud, 2000, xvii + 174 pp., £19.99 hbk, ISBN 0–7509–23873.

Peace Education

Saying No to Violence — Children and Peace: Activities for a Peaceful World By Jan Melichar and Margaret Melicharova Peace Pledge Union, London, 2000, 58 pp., £9.99, ISBN 0–902680–46–3.  相似文献   
109.
《The surgeon》2021,19(5):e153-e167
BackgroundBiopharmaceuticals revolutionised inflammatory bowel disease (IBD) treatment. However, it is postulated they compromise immunity, collagen production and angiogenesis resulting in infective post-operative complications and altered wound/anastomotic healing. Research has failed to agree on risks associated with perioperative biologics therefore it was anticipated that a systematic review may provide a consensus and contribute recommendations for clinical practice.MethodsA systematic review conducted as per PRISMA guidelines included a methodical search of PubMed, Google Scholar, EMBASE/Ovid and Cochrane Library using MeSH and/or keywords for papers published between 01/01/1998 and 04/02/2019.The population analysed included adult ulcerative colitis, Crohn's disease, Indeterminate Colitis or IBD unclassified patients. The intervention was intra-abdominal surgery in patients treated with biological therapy in the preceding 12 weeks compared to patients who had intra-abdominal surgery without biological therapy within the defined timeframe. The primary outcome was surgical site infection (SSI) with secondary outcomes including wound dehiscence, intra-abdominal sepsis/abscess, systemic infection and anastomotic breakdown within 30 days post-procedure. Papers were evaluated by two independent reviewers and those included were assessed for quality/bias using the Newcastle–Ottowa scale.Results2064 UC, Crohn's and IC patients were analysed across 8 included studies. Several studies' multivariate analyses demonstrated corticosteroids to be independent predictors of morbidity. There are no increased complications associated with anti-TNFα exposure while vedolizumab increased SSI and small bowel obstruction.ConclusionProspective studies and randomised control trials are required to clarify study outcomes and recommendations published to date. Presently, biologics should continue to be used and considered beneficial in this population.  相似文献   
110.
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