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31.
Abstract Background : The aim of the present study was to determine the prevalence, associated symptoms, and clinical outcomes of children with acute abdominal pain who had been admitted to an emergency department. Methods : Children aged between 2 and 16 years who presented to the emergency department of Cerrahpa?a Medical School, Istanbul University between July 2001 and August 2002 with acute abdominal pain were enrolled in this study. A questionnaire was completed each patient admitted to our pediatric emergency unit for acute abdominal pain. Data collected included presenting signs and symptoms, the hospital follow up for all children who returned within 10 days, test results, and telephone follow up. Results : The number of children referred to the emergency department was 7442, with 399 (5.4%) of these having acute abdominal pain. The mean age of the study population was 6.9 ± 3.5 years, and 201 of the patients were male. The five most prevalent diagnoses were: (i) upper respiratory tract infection and/or complicated with otitis media or sinusitis (23.7%); (ii) abdominal pain with uncertain etiology (15.4%); (iii) gastroenteritis (15.4%); (iv) constipation (9.4%); and (v) urinary tract infection (8%). The most common associated symptoms were decreased appetite, fever and emesis. Because of follow‐up deficiency the progress of 28 patients was not obtained. Eighty‐two children were referred to the department of pediatric surgery, but only 17 of 82 (20.7%) required surgical intervention (15 of these 17 for appendicitis). Eleven patients returned within 10 days for re‐evaluation, but the initial diagnosis was not changed. The complaints of 57 patients with uncertain etiology were resolved within 2 days. Conclusions : An acute complaint of abdominal pain was usually attributed to a self‐limited disease. However, the percentage of surgical etiology is not negligible.  相似文献   
32.
Neonatal deaths in infants born at term are relatively rare in the USA, occurring in 0.9/1000 live births. Congenital malformations, perinatal asphyxia, infections and inborn errors of metabolism are the leading causes. Chromosomal malformation syndromes, congenital heart disease, pulmonary hypoplasia and severe neural tube defects comprise the majority of lethal malformations. Several skeletal dysplasias are lethal in the newborn infant. Group B Streptococcus still plays a major role in neonatal mortality while deaths due to other infectious agents have decreased. Hypoxic ischaemic encephalopathy is a significant cause of neonatal death. Inborn errors of metabolism have variable presentations but some, such as the fatty acid oxidation disorders, may present in neonates and cause sudden death.  相似文献   
33.
Transgenic techniques provide a tool to generate animals that differ from the wild-type by one or more genes, either by introducing foreign genes (transgenic animals) or by specific mutations of genes (knock-out animals). Most transgenic and knock-out animals are mice and not rats. The frequent use of rat models in the behavioral laboratory, however, will require the increasing application of transgenic techniques in this species. This paper reviews behavioral data from our laboratory as an example of characterizing the behavioral phenotype of a particular transgenic rat, the TGR(mRen2)27 rat. By describing the anxiogenic profile of this rat we also consider some problems associated with such an analysis, with the intention to raise issues that may also apply to studies of behavior in transgenic animals in general.  相似文献   
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Introduction: Irritation reactions are a frequently reported occupational illness. The potential adverse effects of pharmaceutical compounds (PCs) on eye and skin can now be assessed using validated in vitro methods.

Objectives: Our overall aim is to reduce animal testing by replacing the historically utilized in vivo test methods with validated in vitro test methods which accurately determine the ocular and dermal irritation/corrosion potential of PCs to inform worker safety within the pharmaceutical space. Bristol–Myers Squibb (BMS) and the Institute for In Vitro Sciences (IIVS) have therefore conceptualized and internally qualified a tiered in vitro testing strategy to inform occupational hazards regarding eye and skin irritation and corrosivity of PCs. For the small scale pre-qualification phase, we paired historical in vivo and newly generated in vitro data for 15 PCs to determine the predictive capacity of in vitro assays already validated for the eye and skin irritation/corrosion endpoints and accepted for certain regulatory submissions. During the post-qualification phase, a group of 24 PCs were subjected exclusively to the developed tiered testing strategy, which is based on three Organisation for Economic Co-operation and Development (OECD) in vitro methods.

Materials and methods: The qualified in vitro testing strategy utilizes the Corrositex® assay for the corrosivity (OECD TG 435), the Bovine Corneal Opacity and Permeability (BCOP) assay for ocular irritation (OECD TG 437), and the EpiDerm? tissue model-based Skin Irritation Test (SIT) for dermal irritation (OECD TG 439). In the first step, the pH of each PC was determined. For compounds with pH extremes ≥11 or ≤2, the Corrositex® assay was generally conducted first. For compound(s) that were incompatible with or were negative in the Corrositex® assay or had pH values between 2 and 11, the BCOP assay and SIT were performed first.

Results: The results of the tiered testing strategy’s qualification phase demonstrated that the BCOP assay is sensitive enough to identify a wide range of eye irritation/corrosion potentials and its over-prediction rate was considered acceptable to inform occupational hazards and ensure the proper handling practices of PCs. The SIT correctly predicted the skin irritation potential of 14 out of the 15 PCs included in the qualification phase, only over-predicting one PC. In the post-qualification phase, four PCs out of four tested were predicted corrosive by the Corrositex® assay and thus no further testing was needed or conducted. The rest of the PCs were evaluated in the BCOP assay (both neat and as a 20% dilution), with the higher response being used for hazard classification. Four PCs were determined to be severe eye irritants, 1 a moderate irritant, 8 were mild irritants, and 8 were non-irritants. The same set of PCs was evaluated using the SIT and were classified as non-irritants to skin. These results are consistent with the BMS historical in vivo results showing a very low number of PCs as skin irritants.

Conclusions: This tiered in vitro testing strategy, which replaces the use of animal studies, was found to be reasonably accurate in its predictive capacity when compared to historical in vivo results and represents a conservative and reliable platform that can be utilized for the prediction of ocular and dermal irritation/corrosion potential of PCs and for subsequent GHS classification and worker safety hazard communications.  相似文献   
36.
Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
37.
To determine the long-term pulmonary sequelae and effect on exercise tolerance of bronchopulmonary dysplasia (BPD), we studied 10 children at a mean age of 10.4 years, who had been born prematurely, survived respiratory distress syndrome, and subsequently developed BPD, and compared them with eight age-matched normal children born at term. Pulmonary function tests and graded exercise stress tests were performed. Residual volume, the ratio between residual volume and total lung capacity, vital capacity, forced expiratory volume in 1 second, forced expiratory flow between 25% and 75% of vital capacity, and maximal expiratory flows at 80%, 70%, and 60% of total lung capacity were all abnormal (P less than 0.02) in the children with BPD, compared with control values. Pre-exercise transcutaneous CO2 tension was higher (P less than 0.05) in the BPD group than in the control group. At maximal workload, tcPCO2 remained high in patients with BPD compared with control values (P less than 0.05). Arterial oxygen saturation at maximal workload fell below pre-exercise levels in the BPD group (P less than 0.05) but not in control children. There were no differences in maximal oxygen consumption between the BPD group and control children. Exercise-induced bronchospasm occurred in 50% of the BPD group, but not in the control group. We conclude that long-term survivors of BPD have evidence of airway obstruction, hyperinflation, and airway hyperreactivity, compared with a control group. Aerobic fitness was not significantly different in the BPD and control groups, but was achieved in the BPD group at the expense of a fall in SaO2 and a rise in tcPCO2.  相似文献   
38.
OBJECTIVES: The purpose of the study was to compare the postoperative pain of patients who had a hysterectomy through vaginal route according to the process of binding: wire or electrosurgical bipolar vessel sealing. PATIENTS AND METHODS: Retrospective study carried out in the 60 last patients who underwent a hysterectomy by vaginal route for a benign pathology in the gynaecological service of surgery of the CHI Poissy-Saint-Germain-en-Laye until March 2006. Among these patients, 32 had profited from a binding by wire and 28 of the electrosurgical bipolar vessel sealing. The studied criteria were the post-operative pain, total morphine consumption and the durations of the analgesic treatment, the hospitalisation and intervention time. RESULTS: The postoperative pain in the first 24 hours was twice lower using thermofusion; it was valid in immediate post-operative period and after 24 hours. In addition, total morphine consumption was also significantly lower using thermofusion. DISCUSSION AND CONCLUSION: This pilot study shows that the electrosurgical bipolar vessel sealing allows a reduction in the pain into the immediate postoperative period. Other prospective and randomised studies would allow it and conclude on the duration of hospitalisation, the quality of life from the patients and the cost in terms of public health.  相似文献   
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The SV40 T antigen has been used to generate immortalized cells from rheumatoid arthritis (RA) synovial fibroblasts (RASFs) that are commonly used in lieu of primary RASFs. In the current study, we investigated the effect of stimulation by tissue necrosis factor alpha (TNF-α) and interleukin 17 (IL-17) on primary and immortalized RASFs in order to gauge the appropriateness of the use of immortalized RASFs, the MH7A cell line, in the study of RA pathogenesis. Changes in the levels of secretion and expression of 8 proteins associated with RA upon stimulation were assessed by multiplex immunoassay. IL-17 stimulation had a minimal impact on protein secretion and expression for primary and immortalized cells. Basic fibroblast growth factor (FGF-2) was not detectable for the primary cells but was detectable for the immortalized cells. In contrast, monocyte chemoattractant protein 1 (MCP-1) was detectable for primary cells but was undetectable for immortalized cells. In general, protein expression and secretion by cells stimulated with TNF-α were significantly increased. For primary cells, several proteins were below the limit of detection for unstimulated cells and cells stimulated with IL-17, while levels for TNF-α-stimulated cells were within the detectable range. For the same proteins, expression was observed for immortalized cells, regardless of stimulation, suggestive of constitutive activation of the NF-κB signaling pathway. The current study therefore provides strong evidence that immortalized and primary RASFs differ in regard to protein expression and secretion and therefore may not be appropriate for use in the study of RA pathogenesis.  相似文献   
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