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Avian influenza (AI) and Newcastle disease (ND) viruses are heat labile viruses, but exact parameters for heat inactivation at egg pasteurization temperatures have not been established. In this study we artificially infected four egg products with two AI (one low [LP] and one high pathogenicity [HP]) and three ND (two low and one highly virulent) viruses, and determined inactivation curves at 55, 57, 59, 61 and 63 degrees C. Based on D(t) values, the time to inactivation of the viruses was dependent on virus strain and egg product, and was directly related to virus titre, but inversely related to temperature. For all temperatures, the five viruses had the most rapid and complete inactivation in 10% salt yolk, while the most resistant to inactivation was HPAI virus in dried egg white. This study demonstrated that the LPAI and all ND viruses were inactivated in all egg products when treated using industry standard pasteurization protocols. By contrast, the HPAI virus was inactivated in liquid egg products but not in dried egg whites when using the low-temperature industry pasteurization protocol.  相似文献   
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Children and adults with Rubinstein-Taybi Syndrome have specific medical conditions that occur with greater frequency than the general population. Based on the available information from the literature and clinical experience, recommendations for specific surveillance and interventions are made to guide those clinicians caring for individuals with Rubinstein-Taybi Syndrome. This is a first attempt at medical guidelines for individuals with RTS in the United States. On-going research is needed in many areas to guide decisions in medical care and allow for refinement of these medical guidelines.  相似文献   
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Vasculitis with intramural pseudocyst formation primarily in the cerebellar white matter, but also in nuclei of the medulla, resulted in leakage of IgG and albumin and vacuolation of the neuropil (vasogenic oedema) in brains from chickens with clinical signs of Marek's disease virus (MDV)-induced transient paralysis (TP). Demyelination was absent. Chickens that had recovered from TP had a restored blood-brain-barrier, indicated by the rarity of vasculitis and vascular intramural pseudocysts in the cerebellum. In addition, the vacuolation and protein leakage were greatly decreased. The minor vacuolation resulted primarily from intramyelinic (cytotoxic) oedema. The small quantity of extravascular protein was being removed by microglial cells and astrocytes. In one chicken which failed to fully recover from TP (TP-prolonged) there was neither vasogenic oedema, cytotoxic oedema, nor vasculitis in the cerebellum. The medulla of the TP-prolonged chicken had a severe lymphocytosis, swollen axons, neuronal degeneration, secondary demyelination and some associated serum protein leakage. All TP-affected and TP-recovered chickens, and the TP-prolonged chicken, had perivascular mononuclear cell cuffs within all brain sections. Chickens with classical Marek's disease (MD) generally lacked CNS vacuolation, perivascular mononuclear cell cuffs, vasculitis and serum protein leakage. However, in a few cases of MD with severe perivascular mononuclear cell cuffs, focal demyelinating plaques were seen. These plaques had associated vacuolation, serum protein leakage, axonal spheroids and neuronal degeneration.  相似文献   
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Pelvic inflammatory disease: sonographic-pathologic correlation   总被引:3,自引:0,他引:3  
L C Swayne  M B Love  S R Karasick 《Radiology》1984,151(3):751-755
A retrospective analysis of the sonographic findings in 65 women with pelvic inflammatory disease was correlated with pathologic findings at surgery and laparoscopy. Abnormal sonograms could be classified into one of the following three groups: Type I pattern (endometritis); Type II pattern (focal mass); Type III pattern (total pelvic distortion). A simulated uterine appearance, the "pseudouterus sign," was observed in three patients with previous hysterectomy. Various pathologic entities of the pelvic inflammatory disease spectrum could not be reliably distinguished sonographically.  相似文献   
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Vaccination of cats with fowlpox virus expressing the avian influenza (AI) virus H5 hemagglutinin gene (TROVAC AI) resulted in detectable hemagglutination inhibition (HI) antibody responses to the homologous A/Turkey/Ireland/1378/83 (H5N8) (A/tky/Ire/83) AI virus antigen. The HI antibody responses to heterologous A/Chicken/Indonesia/7/03 (H5N1) (A/ck/Indonesia/03) AI virus antigen were also detected in all vaccinated cats, but only after booster vaccinations. The vaccine described in this study and other poxvirus-vectored vaccines may be of value for the prophylaxis of AI virus-associated morbidity and mortality in mammals.  相似文献   
8.
Flies were collected by sweep net from the vicinity of two small groups of "backyard" poultry (10-20 chickens per group) that had been identified as infected with exotic Newcastle disease virus (family Paramyxoviridae, genus avulavirus, ENDV) in Los Angeles County, CA, during the 2002-2003 END outbreak. Collected flies were subdivided into pools and homogenized in brain-heart infusion broth with antibiotics. The separated supernatant was tested for the presence of ENDV by inoculation into embryonated chicken eggs. Exotic Newcastle disease virus was isolated from pools of Phaenicia cuprina (Wiedemann), Fannia canicularis (L.), and Musca domestica L., and it was identified by hemagglutination inhibition with Newcastle disease virus antiserum. Viral concentration in positive pools was low (<1 egg infectious dose50 per fly). Isolated virus demonstrated identical monoclonal antibody binding profiles as well as 99% sequence homology in the 635-bp fusion gene sequence compared with ENDV recovered from infected commercial egg layer poultry during the 2002 outbreak.  相似文献   
9.
艾滋病合并隐球菌脑膜炎18例临床分析   总被引:6,自引:1,他引:6  
目的 提高对艾滋病 (AIDS)合并隐球菌脑膜炎的认识。方法 对赤道几内亚巴塔地区医院 18例AIDS合并隐球菌脑膜炎患者进行临床综合分析。结果  18例AIDS合并隐球菌脑膜炎患者的临床主要表现为 :发热、剧烈头痛、极度乏力、肢体痛、脑膜刺激征及消瘦与脱水等。脑脊液 (CSF)培养均为新型隐球菌生长 ;涂片及隐球菌多糖荚膜抗原 (ELISA法 )检测的阳性率分别为 77 8% (14/ 18) ,94 4% (17/ 18)。结论 隐球菌脑膜炎为AIDS常见机会性感染及主要致死病因之一。  相似文献   
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Background  

High accrual to clinical trials enables new treatment strategies to be tested rapidly, accurately and with generalisability. Ethical standards also must be high so that participation is voluntary and informed. However, this can be difficult to achieve in trials with complex designs and in those which are closely embedded in clinical practice. Optimal recruitment requires a balance of both ethical and accrual considerations. In the context of a trial of stratified treatments for children with acute lymphoblastic leukaemia (UKALL2003) we examined how recruitment looked to an observer and how it felt to the parents, to identify how doctors' communication could promote or inhibit optimal recruitment.  相似文献   
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