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排序方式: 共有620条查询结果,搜索用时 15 毫秒
521.
S Naik GJ Renukaradhya M Rajasekhar MS Shaila 《Canadian Metallurgical Quarterly》1997,15(6-7):603-607
The hemagglutinin (H) protein of Rinderpest virus expressed by a recombinant baculovirus used as a vaccine produced high titres of neutralizing antibody to Rinderpest virus in the vaccinated cattle, comparable to the levels produced by live attenuated vaccine. The immunized cattle were protected against a vaccine-virus challenge, as demonstrated by the failure of development of antibodies to N protein of the vaccine virus. The lack of replication of vaccine virus in the immunized cattle indicated that they are capable of showing a protective response if challenged with a virulent virus. 相似文献
522.
OA al-Rawas R Carter RD Stevenson SK Naik DJ Wheatley 《Canadian Metallurgical Quarterly》1997,12(3):471-8; discussion 478-9
OBJECTIVE: The pulmonary transfer factor for carbon monoxide (TLCO) has been reported to decline following heart transplantation, but the time course of this decline is not well documented. The aim of this study was to define the longitudinal changes in TLCO after heart transplantation. METHODS: Single breath TLCO, lung volumes and expiratory flow rates were prospectively measured in 57 patients (mean age 49 years, range 19-61) before and at least once after heart transplantation. Thirty seven of the 57 patients had four post-transplant assessment which were performed at 6 weeks, 3, 6 and 12 months in 26 patients and at 12, 18, 24 and 36 months in 11 patients. Results were compared with data from 28 normal subjects (mean age 40 years, range 19-61). RESULTS: Before transplantation there was a mild impairment of lung volumes and expiratory flow rates. At 6 weeks after transplantation, there was a further reduction in the forced expiratory volume in one second, forced vital capacity, residual volume and total lung capacity, but all of these increased in the subsequent measurements to exceed their pre-transplant values at about 1 year after transplantation. Haemoglobin-corrected TLCO was also reduced before transplantation compared to normal controls (74.3% and 98.6% of predicted respectively, P < 0.001). Although TLCO per unit alveolar volume (KCO) was relatively preserved in heart transplant candidates, it was still significantly lower than that of normal controls (92.6% and 105.3% of predicted respectively, P < 0.05). After transplantation, mean haemoglobin-corrected TLCO and KCO declined by 12% and 20% of predicted respectively) with the majority of patients having reductions greater than 10% of predicted. The decline in TLCO and KCO was evident at 6 weeks after transplantation with no further changes in the subsequent measurements. CONCLUSIONS: TLCO is reduced in heart transplant candidates and declines further after heart transplantation despite improvement in lung volumes and airway function. The early and non-progressive nature of TLCO decline suggests an aetiology exerting its effect on TLCO within the first 6 weeks after transplantation. 相似文献
523.
A 2-year-old child was admitted with bilateral bronchopneumonia. During convalescence he sustained sudden respiratory arrest for which he required ventilatory support. He had undergone cholecystectomy 1 month prior to the above episode. The pathological examination of the gall bladder mass had revealed the features of metachromatic leukodystrophy. Gastro-oesophageal reflux, which is associated with this neurological disorder, was suspected to be the cause of this sudden respiratory arrest and its presence was confirmed by barium swallow examination. 相似文献
524.
VL Pathi TM Pillay DJ Wheatley PR Belcher SK Naik 《Canadian Metallurgical Quarterly》1997,63(6):1770-1771
A case is reported of dissecting aneurysm of the donor ascending aorta and root 4 years after orthotopic cardiac transplantation. The pathology raises the possibility of Marfan's syndrome in the donor. 相似文献
525.
R Carter OA al-Rawas RD Stevenson SK Naik DJ Wheatley 《Canadian Metallurgical Quarterly》1998,92(4):628-632
In contrast to the standard single-breath transfer factor for carbon monoxide (TLCO), there are no specific guidelines or recommendations for the measurement of its components, the pulmonary capillary blood volume (VC) and membrane component (DM), by the Roughton and Forster method. Ten randomly selected heart transplant patients (three life-long non-smokers, seven ex-smokers > 1 yr, age range 24-55 years) were assessed on two occasions using either the standard or high-oxygen mixture as the first inspired gas in random order. Ten normal subjects (all non-smokers, age range 23-54 years) were assessed on two occasions using either a long protocol (30 min waiting time between repeat measurements in an individual set) or a short protocol (5 min waiting time). Two technically acceptable results of TLCO were used to derive a mean value for DM and VC for each set of measurements (Transflow, P. K. Morgan, Kent, U.K.). The different sequences of gas mixtures produced no significant differences between the values obtained in ten heart transplant patients for mean TLCO (mmol min-1 kPa-1) (standard first 5.13 +/- 1.15, high-oxygen first 5.14 +/- 1.12; limits of agreement -0.57 to 0.59 for DM or for VC. The long or short protocol produced no significant differences between the means of TLCO (mmol min-1 kPa-1) (long 8.0 +/- 1.9, short 8.0 +/- 1.9; limits of agreement -0.5 to 0.5), DM or VC. This allows the development of a standard test protocol of short duration (about 40 min) making it practical for clinical use without compromising the precision or reproducibility of the results obtained. 相似文献
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528.
Pongsakorn Tatongjai Tossapon Boongoen Natthakan Iam-On Nitin Naik Longzhi Yang 《计算机、材料和连续体(英文)》2023,74(2):2479-2490
As more business transactions and information services have been implemented via communication networks, both personal and organization assets encounter a higher risk of attacks. To safeguard these, a perimeter defence like NIDS (network-based intrusion detection system) can be effective for known intrusions. There has been a great deal of attention within the joint community of security and data science to improve machine-learning based NIDS such that it becomes more accurate for adversarial attacks, where obfuscation techniques are applied to disguise patterns of intrusive traffics. The current research focuses on non-payload connections at the TCP (transmission control protocol) stack level that is applicable to different network applications. In contrary to the wrapper method introduced with the benchmark dataset, three new filter models are proposed to transform the feature space without knowledge of class labels. These ECT (ensemble clustering based transformation) techniques, i.e., ECT-Subspace, ECT-Noise and ECT-Combined, are developed using the concept of ensemble clustering and three different ensemble generation strategies, i.e., random feature subspace, feature noise injection and their combinations. Based on the empirical study with published dataset and four classification algorithms, new models usually outperform that original wrapper and other filter alternatives found in the literature. This is similarly summarized from the first experiment with basic classification of legitimate and direct attacks, and the second that focuses on recognizing obfuscated intrusions. In addition, analysis of algorithmic parameters, i.e., ensemble size and level of noise, is provided as a guideline for a practical use. 相似文献
529.
Creation of environmental health information system for public health service: A pilot study 总被引:1,自引:0,他引:1
Ling Li Li Xu Hueiwang Anna Jeng Dayanand Naik Thomas Allen Maria Frontini 《Information Systems Frontiers》2008,10(5):531-542
Despite more than a decade of research on medical information systems, deficiencies exist in our capability of establishing
an effective environmental health information infrastructure. In this research, we present a pilot study on creating a feasible
environmental health information infrastructure. The newly-developed environmental health information system is a web-based
platform that integrates databases, decision-making tools, geographic information systems for supporting public health service
and policy making. The study, which is a part of a comprehensive effort known as Environmental Public Health Tracking proposed
by the Center for Disease Control and Prevention, opens the door for future research on a large scale nation-wide healthcare
information infrastructure.
相似文献
Ling LiEmail: |
530.
Pradeep K. Naik 《国际水资源开发杂志》2017,33(2):326-339
Water is an issue that relates to all aspects of human development in Africa, including health, agriculture, education, economics, and even peace and stability. But the perception that Africa has perpetual water scarcity and is heading towards water crisis is challenged by a significant number of water professionals. Although most agree that Africa suffers from economic water scarcity, physical water scarcity could possibly be controlled with better water management. The large amount of international aid granted annually to Africa is a subject of criticism. This article examines the water crisis in Africa, whether it is a myth or reality, and reasons thereof, and suggests remedial measures. 相似文献