Sensitivity and specificity of serological tests for infectious bronchitis virus antibodies in broilers.

Broilers with maternally-derived immunity (MDI) to infectious bronchitis (IB) were either spray-vaccinated with H120 at 1 day old, or not vaccinated, then challenged at 28 days with one of four different IBV serotypes. Birds were bled frequently and the sera tested by agar gel precipitation (AGP), haemagglutination inhibition (HI), 2 commercial ELISAs, and virus neutralization (VN) to compare the sensitivity and specificity of the assays. The AGP detected a transient response to challenge with a specificity of 100% and a sensitivity of approximately 40%. The ELISAs showed moderate sensitivity and high specificity with sera from non-vaccinated broilers, and high sensitivity and variable specificity with vaccinated birds. Depending on the cut-off value used, the specificity of HI tests was 55 to 100%, while the sensitivity varied widely, making identification of the serotype of an IB challenge unreliable. In vaccinated broilers the sensitivity of the VN tests (used at 21 days post-challenge only) varied from 20 to 100%, while the specificity was dependant on the cut-off value selected. Increases in HI, VN and ELISA titres in vaccinates were generally about half those in non-vaccinates. It is concluded that AGP and ELISA are adequate to detect antibody responses to IBV challenge in both vaccinated and non-vaccinated broilers. In the ELISA, a cut-off value higher than that suggested by the manufacturers is preferred in vaccinated broilers. Similarly, a cut-off value of at least log(2)7 is desirable when attempting to use HI for IB serotyping.     

Study on the local effect of eye-drop vaccination against infectious bronchitis in 1-day-old chicks with maternal antibodies

One-day-old chicks with maternal antibodies to infectious bronchitis virus (IBV) were vaccinated by eye-drop with H120 vaccine strain of IBV. Four weeks later the chicks were challenged by eye-drop or intratracheally with virulent IBV (Massachusetts-type field strain). The chicks were resistant to ocular challenge, but highly susceptible to an intratracheal challenge. After intratracheal challenge the birds showed clinical signs of infectious bronchitis (IB). The immunofluorescence test on IBV was positive. Macroscopical and microscopical lesions were present in the trachea. From these observations it was concluded that the protection against virulent IBV after eye-drop vaccination is localised mainly in the conjunctival and nasal tissues. Thus in vaccination studies with IBV the result of challenge depended highly on the route of application of the challenge virus. Ten days after challenge the neutralisation index of serum for IBV was significantly higher in the intratracheally-challenged chicks as compared with their eye-drop challenged or/and unchallenged mates.     

原发性十二指肠恶性肿瘤的X 线诊断

目的　探讨X线诊断原发性十二指肠恶性肿瘤的价值。方法　回顾性分析 2 1例原发性十二指肠恶性肿瘤的X线所见并与手术病理对照。结果　X线表现包括充盈缺损、黏膜改变、肠腔狭窄和龛影。结论　根据临床及X线表现 ,术前可以正确诊断原发性十二指肠恶性肿瘤。     

导致成人与儿童患者30天脑室腹腔分流失败的原因分析（英文）

OBJECTIVE The aim of this study was to provide a comprehensive benchmark of 30-day ventriculoperitoneal(VP)shunt failure rates for a single institution over a 5-year study period for both adult and pediatric patients,to compare this with the results in previously published literature,and to establish factors associated with shunt failure.METHODS A retrospective database search was undertaken to identify all VP shunt operations performed in a single,regional neurosurgical unit during a 5-year period.Data were collected regarding patient age,sex,origin of hydrocephalus,and whether the shunt was a primary or secondary shunt.Operative notes were used to ascertain the type of valve inserted,which components of the shunt were adjusted/replaced(in revision cases),level of seniority of the most senior surgeon who participated in the operation,and number of surgeons involved in the operation.Where appropriate and where available,postoperative imaging was assessed for grade of shunt placement,using a recognized grading system.Univariate and multivariate models were used to establish factors associated with early(30-day)shunt failure.RESULTS Six hundred eighty-three VP shunt operations were performed,of which 321 were pediatric and 362 were adult.The median duration of postoperative follow-up for nonfailed shunts(excluding deaths)was 1263 days(range 525-2226 days).The pediatric 30-day shunt failure rates in the authors'institution were 8.8%for primary shunts and 23.4%for revisions.In adults,the 30-day shunt failure rates are 17.7%for primary shunts and 25.6%for revisions.In pediatric procedures,the number of surgeons involved in the operating theater was significantly associated with shunt failure rate.In adults,the origin of hydrocephalus was a statistically significant variable.Primary shunts lasted longer than revision shunts,irrespective of patient age.CONCLUSIONS A benchmark of 30-day failures is presented and is consistent with current national databases and previously published data by other groups.The number of surgeons involved in shunt operations and the origin of the patient's hydrocephalus should be described in future studies and should be controlled for in any prospective work.The choice of shunt valve was not a significant predictor of shunt failure.Most previous studies on shunts have concentrated on primary shunts,but the high rate of early shunt failure in revision cases(in both adults and children)is perhaps where future research efforts should be concentrated.     

白芷近缘野生种兴安白芷的生药学研究

目的 对兴安白芷进行系统的生药学研究以区别于其他白芷类药材.方法 按照常规生药学方法进行来源、性状、显微鉴定,按<中国药典>2005年版白芷项下方法进行薄层鉴别与含量测定.结果 找出了兴安白芷在生药性状、组织构造及化学成分上的主要特征.结论 为白芷种质资源的评价提供了参考依据.